1.11.1

Fix trace-event import for many cases where there are 'ts' collisions (#322 )
The trace event format has a very unfortunate combination of requirements in order to give a best-effort interpretation of a given trace file: 1. Events may be recorded out-of-order by timestamp 2. Events with the *same* timestamp should be processed in the order they were provided in the file. Mostly. The first requirement is written explicitly [in the spec](https://docs.google.com/document/d/1CvAClvFfyA5R-PhYUmn5OOQtYMH4h6I0nSsKchNAySU/preview). > The events do not have to be in timestamp-sorted order. The second one isn't explicitly written, but it's implicitly true because otherwise the interpretation of a file is ambiguous. For example, the following file has all events with the same `ts` field, but re-ordering the fields changes the interpretation. ``` [ { "pid": 0, "tid": 0, "ph": "X", "ts": 0, "dur": 20, "name": "alpha" }, { "pid": 0, "tid": 0, "ph": "X", "ts": 0, "dur": 20, "name": "beta" } } ``` If we allowed arbitrary reordering, it would be ambiguous whether the alpha frame should be nested inside of the beta frame or vice versa. Since traces are interpreted as call trees, it's not okay to just arbitrarily choose. So you might next guess that a reasonable approach would be to do a [stable sort](https://wiki.c2.com/?StableSort) by "ts", then process the events one-by-one. This almost works, except for two additional problems. The first problem is that in some situations this would still yield invalid results. ``` [ {"pid": 0, "tid": 0, "ph": "B", "name": "alpha", "ts": 0}, {"pid": 0, "tid": 0, "ph": "B", "name": "beta", "ts": 0}, {"pid": 0, "tid": 0, "ph": "E", "name": "alpha", "ts": 1}, {"pid": 0, "tid": 0, "ph": "E", "name": "beta", "ts": 1} ] ``` If we were to follow this rule, we would try to execute the `"E"` for alpha before the `"E"` for beta, even though beta is on the top of the stack. So in *that* case, we actually need to execute the `"E"` for beta first, otherwise the resulting profile is incorrect. The other problem with this approach of using the stable sort order is the question of how to deal with `"X"` events. speedscope translates `"X"` events into a `"B"` and `"E"` event pair. But where should it put the `"E"` event? Your first guess might be "at the index where the `"X"` events occur in the file". This runs into trouble in cases like this: ``` [ { "pid": 0, "tid": 0, "ph": "X", "ts": 9, "dur": 1, "name": "beta" }, { "pid": 0, "tid": 0, "ph": "X", "ts": 9, "dur": 2, "name": "gamma" }, ] ``` The most natural translation of this would be to convert it into the following `"B"` and `"E"` events: ``` [ { "pid": 0, "tid": 0, "ph": "B", "ts": 9, "name": "beta" }, { "pid": 0, "tid": 0, "ph": "E", "ts": 10, "name": "beta" }, { "pid": 0, "tid": 0, "ph": "B", "ts": 9, "name": "gamma" }, { "pid": 0, "tid": 0, "ph": "E", "ts": 11, "name": "gamma" }, ] ``` Which, after a stable sort turns into this: ``` [ { "pid": 0, "tid": 0, "ph": "B", "ts": 9, "name": "beta" }, { "pid": 0, "tid": 0, "ph": "B", "ts": 9, "name": "gamma" }, { "pid": 0, "tid": 0, "ph": "E", "ts": 10, "name": "beta" }, { "pid": 0, "tid": 0, "ph": "E", "ts": 11, "name": "gamma" }, ] ``` Notice that we again have a problem where we open "beta" before "gamma", but we need to close "beta" first because it ends first! Ultimately, I couldn't figure out any sort order that would allow me to predict ahead-of-time what order to process the events in. So instead, I create two event queues: one for `"B"` events, and one for `"E"` events, and then try to be clever about how I merge them together. AFAICT, chrome://tracing does not sort events before processing them, which is kind of baffling. But chrome://tracing also has really bizarre behaviour for things like this where the resulting flamegraph isn't even a valid tree (there are overlapping ranges): ``` [ { "pid": 0, "tid": 0, "ph": "X", "ts": 0, "dur": 10, "name": "alpha" }, { "pid": 0, "tid": 0, "ph": "X", "ts": 5, "dur": 10, "name": "beta" } } ``` So I'm going to call this "good enough" for now. Fixes #223 Fixes #320
2020-10-25 01:50:28 -07:00 · 2020-10-25 01:45:13 -07:00 · 2020-10-24 21:58:31 -07:00 · 2020-10-13 01:05:26 -07:00 · 2020-10-12 18:03:31 -07:00 · 2020-10-11 12:05:20 -07:00
153 changed files with 45479 additions and 10337 deletions
@@ -1,13 +1,20 @@
 module.exports = {
-  parser: 'typescript-eslint-parser',
+  parser: '@typescript-eslint/parser',
  parserOptions: {
    sourceType: 'module',
    ecmaFeatures: {
      jsx: true,
    },
  },
-  plugins: ['prettier'],
+  plugins: ['prettier', '@typescript-eslint', 'react-hooks'],
  rules: {
-    'prettier/prettier': 'error',
+    '@typescript-eslint/explicit-function-return-type': 'off',
+    'react-hooks/rules-of-hooks': 'error',
+    'react-hooks/exhaustive-deps': [
+      'error',
+      {
+        additionalHooks: '(useSelector|useAppSelector|useActionCreator)',
+      },
+    ],
  },
-};
+}
@@ -0,0 +1,43 @@
+name: Node.js CI
+
+on:
+  push:
+    branches:
+      - master
+  pull_request:
+
+jobs:
+  test:
+    runs-on: ubuntu-latest
+
+    strategy:
+      matrix:
+        node-version: [10.x, 12.x, 14.x]
+
+    steps:
+      - uses: actions/checkout@v2
+      - name: Use Node.js ${{ matrix.node-version }}
+        uses: actions/setup-node@v1
+        with:
+          node-version: ${{ matrix.node-version }}
+      - run: npm install
+      - run: npm test
+        env:
+          CI: true
+
+      - name: Coveralls Parallel
+        uses: coverallsapp/github-action@master
+        with:
+          github-token: ${{ secrets.github_token }}
+          flag-name: run-${{ matrix.node-version }}
+          parallel: true
+
+  finish:
+    needs: test
+    runs-on: ubuntu-latest
+    steps:
+      - name: Coveralls Finished
+        uses: coverallsapp/github-action@master
+        with:
+          github-token: ${{ secrets.github_token }}
+          parallel-finished: true
@@ -1,3 +0,0 @@
-language: node_js
-node_js:
-  - '9'
@@ -1,114 +1,230 @@
-## Unreleased
+## [1.11.1] - 2020-10-25
+
+### Fixed
+
+- Fix trace-event import for many cases where there are 'ts' collisions [[#322](https://github.com/jlfwong/speedscope/pull/322)]
+- Fix import of trace event files where B/E events' args don't match [[#321](https://github.com/jlfwong/speedscope/pull/321)]
+
+## [1.11.0] - 2020-10-13
+
+### Added
+
+- Support remapping profiles using source maps [[#317](https://github.com/jlfwong/speedscope/pull/317)]
+
+### Fixed
+
+- Fix line & column numbers in imports from Chrome & Firefox [[#318](https://github.com/jlfwong/speedscope/pull/318)]
+
+## [1.10.0] - 2020-09-29
+
+### Added
+
+- Support for importing profiles from Safari [[#300](https://github.com/jlfwong/speedscope/pull/300)] (by [@radex](https://github.com/radex))
+
+### Fixed
+
+- Fixed browser not opening on Windows when using the CLI [[#307](https://github.com/jlfwong/speedscope/pull/307)] (by [@spillerrec](https://github.com/spillerrec))
+- Fixed import of UTF-16 encoded files w/ BOM [[#314](https://github.com/jlfwong/speedscope/pull/314)]
+- Removed accidental dependency on React [[#315](https://github.com/jlfwong/speedscope/pull/315)]
+
+## [1.9.0] - 2020-08-05
+
+### Added
+
+- Provide prev/next buttons to cycle through search results, make search results more visually prominen [[#304](https://github.com/jlfwong/speedscope/pull/304)]
+
+### Fixed
+
+- Fix accumulated errors in Chrome profile imports caused by zeroed negative timeDeltas [[#305](https://github.com/jlfwong/speedscope/pull/305)] (by [@taneliang](https://github.com/taneliang))
+
+## [1.8.0] - 2020-07-19
+
+### Added
+
+- Added search highlighting in time order & left heavy views [[#297](https://github.com/jlfwong/speedscope/pull/297)]
+
+### Fixed
+
+- Fix performance issues for the caller/callee flamegraphs in the sandwich view [[#296](https://github.com/jlfwong/speedscope/pull/296)]
+
+## [1.7.0] - 2020-07-13
+
+### Added
+
+- Introduced filtering via Ctrl+F/Cmd+F into the sandwich view [[#293](https://github.com/jlfwong/speedscope/pull/293)]
+
+## [1.6.0] - 2020-05-30
+
+### Added
+
+- Improved profile/thread selection UI [[#282](https://github.com/jlfwong/speedscope/pull/282)]
+
+### Fixed
+
+- Crash instead of incorrectly interpreting profiles with incorrectly ordered events [[#273](https://github.com/jlfwong/speedscope/pull/273)]
+- A large refactor to upgrade to Preact X was performed [[#267](https://github.com/jlfwong/speedscope/pull/267)]
+
+## [1.5.3] - 2020-01-16
+
+### Fixed
+
+- Bump dependency versions to unbreak build [[#253](https://github.com/jlfwong/speedscope/pull/253)] (by [@jlfwong](https://github.com/jlfwong), with changes from [@Archerlly](https://github.com/Archerlly)'s [#215](https://github.com/jlfwong/speedscope/pull/215))
+- Trace event: Prevent event re-ordering from generating incorrect flamegraphs ([#252](https://github.com/jlfwong/speedscope/pull/252), with changes from [@hwajaywang](https://github.com/hwajaywang)'s [#249](https://github.com/jlfwong/speedscope/pull/249))
+- Make tooltip width wider [[#239](https://github.com/jlfwong/speedscope/pull/239)] (by [@miso11](https://github.com/miso11))
+
+## [1.5.2] - 2019-10-10
+
+### Fixed
+
+- Fix emscripten remapping when symbols are hex-escaped, like `a\20b` [[#233](https://github.com/jlfwong/speedscope/pull/233)] (by [@jyc](https://github.com/jyc))
+
+## [1.5.1] - 2019-06-06
+
+### Fixed
+
+- Fixed import of trace event files which contain unmatched "E" events ([#222](https://github.com/jlfwong/speedscope/pull/222)) (by [@jlfwong](https://github.com/jlfwong))
+
+## [1.5.0] - 2019-02-17
+
+### Added
+
+- Support importing unterminated JSON in simple cases ([#208](https://github.com/jlfwong/speedscope/pull/208)) (by [@jlfwong](https://github.com/jlfwong))
+
+### Fixed
+
+- Fix crash when importing from stackprof without raw_timestamp_deltas ([#207](https://github.com/jlfwong/speedscope/pull/207)) (by [@jlfwong](https://github.com/jlfwong))
+- Alert instead of crash when importing a file containing no profiles ([#205](https://github.com/jlfwong/speedscope/pull/205)) (by [@jlfwong](https://github.com/jlfwong))
+- Fixed import of multithreaded profiles from Chrome 66 ([#206](https://github.com/jlfwong/speedscope/pull/206)) (by [@jlfwong](https://github.com/jlfwong))
+- Fixed import of instruments trace files with missing run number ([#203](https://github.com/jlfwong/speedscope/pull/203)) (by [@Archerlly](https://github.com/Archerlly))
+
+## [1.4.1] - 2019-01-22
+
+### Fixed
+
+- Fix importing of Trace Event Format files with no ts field on M events [[#198](https://github.com/jlfwong/speedscope/pull/198)] (by [@jlfwong](https://github.com/jlfwong))
+
+## [1.4.0] - 2019-01-22
+
+### Added
+
+- Import v8 cpu profile (old format) [[#177](https://github.com/jlfwong/speedscope/pull/177)] (by [@vmarchaud](https://github.com/vmarchaud))
+- Import basic "Trace Event Format" profiles [[#197](https://github.com/jlfwong/speedscope/pull/197)] (by [@jlfwong](https://github.com/jlfwong))
+
+## [1.3.2] - 2018-12-03
+
+### Fixed
+
+- Fixed import of multithreaded Chrome profiles [[#19](https://github.com/jlfwong/speedscope/pull/19)] (by [@jlfwong](https://github.com/jlfwong))

 ## [1.3.1] - 2018-11-08

 ### Fixed

-* Fixed a file import performance regression by using TextDecoder [#188] (by @jlfwong)
+- Fixed a file import performance regression by using TextDecoder [[#188](https://github.com/jlfwong/speedscope/pull/188)] (by [@jlfwong](https://github.com/jlfwong))

 ## [1.3.0] - 2018-10-29

 ### Added

-* Support import from Haskell GHC JSON format support [#183] (by @trishume)
+- Support import from Haskell GHC JSON format support [[#183](https://github.com/jlfwong/speedscope/pull/183)] (by [@trishume](https://github.com/trishume))

 ### Fixed

-* Make the wasd keymappings work on azerty keyboards [#184] (by @vrischmann)
-* Fix import of binary formats via profileURL [#179] (by @f-hj)
+- Make the wasd keymappings work on azerty keyboards [[#184](https://github.com/jlfwong/speedscope/pull/184)] (by [@vrischmann](https://github.com/vrischmann))
+- Fix import of binary formats via profileURL [[#179](https://github.com/jlfwong/speedscope/pull/179)] (by [@f](https://github.com/f)-hj)

 ## [1.2.0] - 2018-10-08

 ### Added

-* Add import of v8 heap allocation profile [#170] (by @vmarchaud)
+- Add import of v8 heap allocation profile [[#170](https://github.com/jlfwong/speedscope/pull/170)] (by [@vmarchaud](https://github.com/vmarchaud))

 ## [1.1.0] - 2018-09-26

 ### Added

-* Add go tool pprof import support [#165]
+- Add go tool pprof import support [[#165](https://github.com/jlfwong/speedscope/pull/165)]

 ## [1.0.4] - 2018-09-12

 ### Fixed

-* Fix import from Chrome < 69 when there are multiple profiles [#161]
+- Fix import from Chrome < 69 when there are multiple profiles [[#161](https://github.com/jlfwong/speedscope/pull/161)]

 ## [1.0.3] - 2018-09-10

 ### Fixed

-* Fix import for Chrome 69, support leading idle time before first call [#160]
+- Fix import for Chrome 69, support leading idle time before first call [[#160](https://github.com/jlfwong/speedscope/pull/160)]

 ## [1.0.2] - 2018-09-04

 ### Fixed

-* Allow optional CR before LF when probing collapsed stacks files [#154]
-* Fix import for Firefox 63 [#156]
-* Change time formatting for minutes from 1.50min to 1:30 [#153] (by @Alex-Diez)
+- Allow optional CR before LF when probing collapsed stacks files [[#154](https://github.com/jlfwong/speedscope/pull/154)]
+- Fix import for Firefox 63 [[#156](https://github.com/jlfwong/speedscope/pull/156)]
+- Change time formatting for minutes from 1.50min to 1:30 [[#153](https://github.com/jlfwong/speedscope/pull/153)] (by [@Alex](https://github.com/Alex)-Diez)

 ## [1.0.1] - 2018-08-23

-* Fixed an issue where flamegraph bounds were not always being cleared correctly, leading to visual artifacts [#150]
+- Fixed an issue where flamegraph bounds were not always being cleared correctly, leading to visual artifacts [[#150](https://github.com/jlfwong/speedscope/pull/150)]

 ## [1.0.0] - 2018-08-23

 ### Fixed

-* Fixed rendering issues when switching between screens w/ different `devicePixelRatios` [#147]
+- Fixed rendering issues when switching between screens w/ different `devicePixelRatios` [[#147](https://github.com/jlfwong/speedscope/pull/147)]

 ## [0.7.1] - 2018-08-20

 ### Fixed

-* Removed dependency on regl in order to allow speedscope to run in strict content-security-policy environments [#140]
-* Fixed text culling bug [#143]
+- Removed dependency on regl in order to allow speedscope to run in strict content-security-policy environments [[#140](https://github.com/jlfwong/speedscope/pull/140)]
+- Fixed text culling bug [[#143](https://github.com/jlfwong/speedscope/pull/143)]

 ## [0.7.0] - 2018-08-16

 ### Added

-* Added support to import from linux `perf script` [#135]
+- Added support to import from linux `perf script` [[#135](https://github.com/jlfwong/speedscope/pull/135)]

 ## [0.6.0] - 2018-08-14

 ### Added

-* Added support for multiple threads/processes [#130]
-* Import all runs & threads from Instruments .trace files instead of just main thread from selected run [#130]
+- Added support for multiple threads/processes [[#130](https://github.com/jlfwong/speedscope/pull/130)]
+- Import all runs & threads from Instruments .trace files instead of just main thread from selected run [[#130](https://github.com/jlfwong/speedscope/pull/130)]

 ### Fixed

-* Ensure the JSON schema has actual contents [#133]
+- Ensure the JSON schema has actual contents [[#133](https://github.com/jlfwong/speedscope/pull/133)]

 ## [0.5.1] - 2018-08-09

 ### Fixed

-* Fixed broken CLI
+- Fixed broken CLI

 ## [0.5.0] - 2018-08-09

 ### Fixed

-* Fix emscripten remapping when symbols contain dashes, like `527:i32s-div` [#129]
-* Improved firefox import speed and fixed bugs in it [#128]
-* Prevent non-contiguous blocks in the time ordered flamechart from appearing as a single node for selection [#123]
-* Prevent dragging from changing selection [#122]
-* Clamp zoom to prevent floating point issues [#121]
-* Preserve view state when switching tabs [#100]
+- Fix emscripten remapping when symbols contain dashes, like `527:i32s-div` [[#129](https://github.com/jlfwong/speedscope/pull/129)]
+- Improved firefox import speed and fixed bugs in it [[#128](https://github.com/jlfwong/speedscope/pull/128)]
+- Prevent non-contiguous blocks in the time ordered flamechart from appearing as a single node for selection [[#123](https://github.com/jlfwong/speedscope/pull/123)]
+- Prevent dragging from changing selection [[#122](https://github.com/jlfwong/speedscope/pull/122)]
+- Clamp zoom to prevent floating point issues [[#121](https://github.com/jlfwong/speedscope/pull/121)]
+- Preserve view state when switching tabs [[#100](https://github.com/jlfwong/speedscope/pull/100)]

 ## [0.4.0] - 2018-07-21

 ### Added

-* Support for importing v8 logs from node [#98]
-* Optionally read from stdin via cli [#99]
+- Support for importing v8 logs from node [[#98](https://github.com/jlfwong/speedscope/pull/98)]
+- Optionally read from stdin via cli [[#99](https://github.com/jlfwong/speedscope/pull/99)]

 ## [0.3.0] - 2018-07-18

 ### Added

-* Support for remapping profiles using a wasm symbol file [#93]
+- Support for remapping profiles using a wasm symbol file [[#93](https://github.com/jlfwong/speedscope/pull/93)]
@@ -36,15 +36,24 @@ speedscope is designed to ingest profiles from a variety of different profilers
 - JavaScript
  - [Importing from Chrome](https://github.com/jlfwong/speedscope/wiki/Importing-from-Chrome)
  - [Importing from Firefox](https://github.com/jlfwong/speedscope/wiki/Importing-from-Firefox)
+  - [Importing from Safari](https://github.com/jlfwong/speedscope/wiki/Importing-from-Safari)
  - [Importing from Node.js](https://github.com/jlfwong/speedscope/wiki/Importing-from-Node.js)
 - Ruby
  - [Importing from stackprof](https://github.com/jlfwong/speedscope/wiki/Importing-from-stackprof-(ruby))
  - [Importing from rbspy](https://github.com/jlfwong/speedscope/wiki/Importing-from-rbspy-(ruby))
+  - [Importing from ruby-prof](https://github.com/jlfwong/speedscope/wiki/Importing-from-ruby-prof)
+- Python
+  - [Importing from py-spy](https://github.com/jlfwong/speedscope/wiki/Importing-from-py-spy-(python))
+  - [pyspeedscope](https://github.com/windelbouwman/pyspeedscope)
+  - [Importing from Austin](https://github.com/P403n1x87/austin-python#format-conversion)
 - Go
  - [Importing from pprof](https://github.com/jlfwong/speedscope/wiki/Importing-from-pprof-(go))  
+- Rust
+  - [flamescope](https://github.com/coolreader18/flamescope)
 - Native code
  - [Importing from Instruments.app](https://github.com/jlfwong/speedscope/wiki/Importing-from-Instruments.app) (macOS)
  - [Importing from `perf`](https://github.com/jlfwong/speedscope/wiki/Importing-from-perf-(linux)) (linux)
+- [Importing from .NET Core](https://github.com/jlfwong/speedscope/wiki/Importing-from-.NET-Core)
 - [Importing from GHC (Haskell)](https://github.com/jlfwong/speedscope/wiki/Importing-from-Haskell)
 - [Importing from custom sources](https://github.com/jlfwong/speedscope/wiki/Importing-from-custom-sources)

@@ -108,6 +117,8 @@ Once a profile has loaded, the main view is split into two: the top area is the
 * `Cmd+O`/`Ctrl+O` to open a new profile
 * `n`: Go to next profile/thread if one is available
 * `p`: Go to previous profile/thread if one is available
+* `t`: Open the profile/thread selector if available
+* `Cmd+F`/`Ctrl+F`: to open search. While open, `Enter` and `Shift+Enter` cycle through results

 ## Contributing

@@ -4,7 +4,7 @@ const fs = require('fs')
 const os = require('os')
 const stream = require('stream')

-const opn = require('opn')
+const open = require('open')

 const helpString = `Usage: speedscope [filepath]

@@ -89,7 +89,11 @@ async function main() {

  console.log('Opening', urlToOpen, 'in your default browser')

-  await opn(urlToOpen, {wait: false})
+  // We'd like to avoid blocking the terminal on the browsing closing,
+  // but for some reason this doesn't work at all on Windows if we
+  // don't use wait: true.
+  const wait = process.platform === "win32";
+  await open(urlToOpen, {wait})
 }

 main()
@@ -1,6 +1,6 @@
 {
  "name": "speedscope",
-  "version": "1.3.1",
+  "version": "1.11.1",
  "description": "",
  "repository": "jlfwong/speedscope",
  "main": "index.js",
@@ -13,48 +13,71 @@
    "prettier": "prettier --write 'src/**/*.ts' 'src/**/*.tsx'",
    "lint": "eslint 'src/**/*.ts' 'src/**/*.tsx'",
    "jest": "./scripts/test-setup.sh && jest --runInBand",
-    "coverage": "npm run jest -- --coverage && coveralls < coverage/lcov.info",
-    "test": "tsc --noEmit && npm run lint && npm run coverage",
+    "coverage": "npm run jest -- --coverage",
+    "typecheck": "tsc --noEmit",
+    "test": "./scripts/ci.sh",
    "serve": "parcel assets/index.html --open --no-autoinstall"
  },
-  "files": ["bin/cli.js", "dist/release/**", "!*.map"],
-  "browserslist": ["last 2 Chrome versions", "last 2 Firefox versions"],
+  "files": [
+    "bin/cli.js",
+    "dist/release/**",
+    "!*.map"
+  ],
+  "browserslist": [
+    "last 2 Chrome versions",
+    "last 2 Firefox versions"
+  ],
  "author": "",
  "license": "MIT",
  "devDependencies": {
    "@types/jest": "22.2.3",
    "@types/jszip": "3.1.4",
-    "@types/node": "10.1.4",
+    "@types/node": "14.0.1",
    "@types/pako": "1.0.0",
+    "@typescript-eslint/eslint-plugin": "2.33.0",
+    "@typescript-eslint/parser": "2.33.0",
+    "acorn": "7.2.0",
    "aphrodite": "2.1.0",
-    "coveralls": "3.0.1",
-    "eslint": "4.19.1",
+    "eslint": "6.0.0",
    "eslint-plugin-prettier": "2.6.0",
-    "jest": "23.0.1",
+    "eslint-plugin-react-hooks": "4.0.2",
+    "jest": "24.3.0",
    "jsverify": "0.8.3",
    "jszip": "3.1.5",
    "pako": "1.0.6",
-    "parcel-bundler": "1.9.2",
-    "preact": "8.2.7",
-    "preact-redux": "jlfwong/preact-redux#a56dcc4",
-    "prettier": "1.12.0",
+    "parcel-bundler": "1.12.4",
+    "preact": "10.4.1",
+    "prettier": "2.0.4",
    "protobufjs": "6.8.8",
-    "quicktype": "15.0.45",
-    "redux": "^4.0.0",
-    "ts-jest": "22.4.6",
-    "typescript": "2.8.1",
+    "redux": "^4.0.5",
+    "source-map": "0.6.1",
+    "ts-jest": "24.3.0",
+    "typescript": "3.9.2",
    "typescript-eslint-parser": "17.0.1",
+    "typescript-json-schema": "0.42.0",
    "uglify-es": "3.2.2"
  },
  "jest": {
    "transform": {
      "^.+\\.tsx?$": "ts-jest"
    },
+    "setupFilesAfterEnv": [
+      "./src/jest-setup.js"
+    ],
    "testRegex": "\\.test\\.tsx?$",
-    "collectCoverageFrom": ["**/*.{ts,tsx}", "!**/*.d.{ts,tsx}"],
-    "moduleFileExtensions": ["ts", "tsx", "js", "jsx", "json"]
+    "collectCoverageFrom": [
+      "**/*.{ts,tsx}",
+      "!**/*.d.{ts,tsx}"
+    ],
+    "moduleFileExtensions": [
+      "ts",
+      "tsx",
+      "js",
+      "jsx",
+      "json"
+    ]
  },
  "dependencies": {
-    "opn": "5.3.0"
+    "open": "7.2.0"
  }
 }
@@ -4,4 +4,5 @@ module.exports = {
  semi: false,
  singleQuote: true,
  trailingComma: 'all',
-};
+  arrowParens: 'avoid'
+}
@@ -0,0 +1 @@
+{"head":{"functionName":"(root)","url":"","lineNumber":-1,"bailoutReason":"","id":1,"scriptId":0,"hitCount":0,"children":[{"functionName":"","url":"","lineNumber":0,"callUID":1,"bailoutReason":"","id":2,"scriptId":0,"hitCount":0,"children":[{"functionName":"a","url":"","lineNumber":0,"callUID":2,"bailoutReason":"","id":3,"scriptId":0,"hitCount":0,"children":[{"functionName":"b","url":"","lineNumber":5,"callUID":3,"bailoutReason":"","id":4,"scriptId":0,"hitCount":0,"children":[{"functionName":"d","url":"","lineNumber":13,"callUID":4,"bailoutReason":"","id":5,"scriptId":0,"hitCount":14,"children":[]}]},{"functionName":"c","url":"","lineNumber":9,"callUID":3,"bailoutReason":"","id":6,"scriptId":0,"hitCount":0,"children":[{"functionName":"d","url":"","lineNumber":13,"callUID":6,"bailoutReason":"","id":7,"scriptId":0,"hitCount":14,"children":[]}]}]}]}]},"startTime":163140,"endTime":163140,"samples":[2,5,5,5,5,5,5,5,5,5,5,5,5,5,5,7,7,7,7,7,7,7,7,7,7,7,7,7,7],"timestamps":[163140599286,163140610861,163140611921,163140612966,163140614236,163140615507,163140616694,163140617968,163140619238,163140620258,163140621507,163140622765,163140624037,163140625303,163140626378,163140627649,163140628923,163140630191,163140631457,163140632746,163140634032,163140635304,163140636440,163140637716,163140638990,163140640255,163140641520,163140642791,163140644063,163140645206]}
@@ -0,0 +1,4 @@
+This directory contains profiles & source-maps to test if source-map
+remapping of profiles is working correctly. See the corresponding
+"sourcemaps" directory in programs/javascript to see how these were
+generated.
@@ -0,0 +1,7 @@
+{
+  "version": 3,
+  "sources": ["gamma.ts", "beta.ts", "delta.ts", "alpha.ts", "kludge.ts", "typescript-source-map-test.ts"],
+  "sourcesContent": ["export const gamma = () => {\n  let prod = 1\n  for (let i = 1; i < 1000; i++) {\n    prod *= i\n  }\n  return prod\n}\n", "import {gamma} from './gamma'\n\nexport function beta() {\n  for (let i = 0; i < 10; i++) {\n    gamma()\n  }\n}\n", "import {gamma} from './gamma'\n\nexport const delta = function () {\n  for (let i = 0; i < 10; i++) {\n    gamma()\n  }\n}\n", "import {beta} from './beta'\nimport {delta} from './delta'\n\nexport function alpha() {\n  ;(function () {\n    for (let i = 0; i < 1000; i++) {\n      beta()\n      delta()\n    }\n  })()\n}\n", "import {alpha} from './alpha'\n\nexport class Kludge {\n  constructor() {\n    alpha()\n    console.log(this.floop)\n  }\n\n  zap() {\n    alpha()\n  }\n\n  get floop(): number {\n    alpha()\n    return 1\n  }\n}\n", "import {Kludge} from './kludge'\n\nconst k = new Kludge()\nk.zap()\n"],
+  "mappings": "MAAO,KAAM,GAAQ,KACnB,GAAI,GAAO,EACX,OAAS,GAAI,EAAG,EAAI,IAAM,IACxB,GAAQ,EAEV,MAAO,ICHF,aACL,OAAS,GAAI,EAAG,EAAI,GAAI,IACtB,ICFG,KAAM,GAAQ,WACnB,OAAS,GAAI,EAAG,EAAI,GAAI,IACtB,KCDG,aACJ,AAAC,YACA,OAAS,GAAI,EAAG,EAAI,IAAM,IACxB,IACA,QCPN,QAGE,cACE,IACA,QAAQ,IAAI,KAAK,OAGnB,MACE,OAGE,SACF,WACO,GCZX,KAAM,GAAI,GAAI,GACd,EAAE",
+  "names": []
+}
@@ -0,0 +1 @@
+{"version":3,"sources":["gamma.ts","beta.ts","delta.ts","alpha.ts","kludge.ts","typescript-source-map-test.ts"],"names":[],"mappings":";AAAO,aAAA,OAAA,eAAA,QAAA,aAAA,CAAA,OAAA,IAAA,QAAA,WAAA,EAAA,IAAM,EAAQ,WAEd,IADD,IAAA,EAAO,EACF,EAAI,EAAG,EAAI,IAAM,IACxB,GAAQ,EAEH,OAAA,GALF,QAAA,MAAA;;ACMN,aAAA,OAAA,eAAA,QAAA,aAAA,CAAA,OAAA,IAAA,QAAA,KAAA,EAND,IAAA,EAAA,QAAA,WAEM,SAAU,IACT,IAAA,IAAI,EAAI,EAAG,EAAI,GAAI,KACtB,EAAA,EAAA;;ACFG,aAAA,OAAA,eAAA,QAAA,aAAA,CAAA,OAAA,IAAA,QAAA,WAAA,EAFP,IAAA,EAAA,QAAA,WAEa,EAAQ,WACd,IAAA,IAAI,EAAI,EAAG,EAAI,GAAI,KACtB,EAAA,EAAA,UAFG,QAAA,MAAA;;ACQN,aAAA,OAAA,eAAA,QAAA,aAAA,CAAA,OAAA,IAAA,QAAA,MAAA,EAVD,IAAA,EAAA,QAAA,UACA,EAAA,QAAA,WAEM,SAAU,KACZ,WACK,IAAA,IAAI,EAAI,EAAG,EAAI,IAAM,KACxB,EAAA,EAAA,SACA,EAAA,EAAA,SAHF;;ACFJ,aAAA,OAAA,eAAA,QAAA,aAAA,CAAA,OAAA,IAAA,QAAA,YAAA,EAFA,IAAA,EAAA,QAAA,WAEA,EAAA,WACE,SAAA,KACE,EAAA,EAAA,SACA,QAAQ,IAAI,KAAK,OAWrB,OARE,EAAA,UAAA,IAAA,YACE,EAAA,EAAA,UAGF,OAAA,eAAI,EAAA,UAAA,QAAK,CAAT,IAAA,WAES,OADP,EAAA,EAAA,SACO,GAFA,YAAA,EAVX,cAAA,IAcA,EAdA,GAAA,QAAA,OAAA;;ACCA,aAHA,IAAA,EAAA,QAAA,YAEM,EAAI,IAAI,EAAJ,OACV,EAAE","file":"typescript-source-map-test.js","sourceRoot":"..","sourcesContent":["export const gamma = () => {\n  let prod = 1\n  for (let i = 1; i < 1000; i++) {\n    prod *= i\n  }\n  return prod\n}\n","import {gamma} from './gamma'\n\nexport function beta() {\n  for (let i = 0; i < 10; i++) {\n    gamma()\n  }\n}\n","import {gamma} from './gamma'\n\nexport const delta = function () {\n  for (let i = 0; i < 10; i++) {\n    gamma()\n  }\n}\n","import {beta} from './beta'\nimport {delta} from './delta'\n\nexport function alpha() {\n  ;(function () {\n    for (let i = 0; i < 1000; i++) {\n      beta()\n      delta()\n    }\n  })()\n}\n","import {alpha} from './alpha'\n\nexport class Kludge {\n  constructor() {\n    alpha()\n    console.log(this.floop)\n  }\n\n  zap() {\n    alpha()\n  }\n\n  get floop(): number {\n    alpha()\n    return 1\n  }\n}\n","import {Kludge} from './kludge'\n\nconst k = new Kludge()\nk.zap()\n"]}
@@ -0,0 +1 @@
+{"version":3,"sources":["webpack://speedscope-sourcemap-test-project/./gamma.ts","webpack://speedscope-sourcemap-test-project/./beta.ts","webpack://speedscope-sourcemap-test-project/./delta.ts","webpack://speedscope-sourcemap-test-project/./alpha.ts","webpack://speedscope-sourcemap-test-project/./typescript-source-map-test.ts","webpack://speedscope-sourcemap-test-project/./kludge.ts"],"names":["gamma","prod","i","beta","delta","alpha","console","log","this","floop","zap"],"mappings":"mBAAO,IAAMA,EAAQ,WAEnB,IADA,IAAIC,EAAO,EACFC,EAAI,EAAGA,EAAI,IAAMA,IACxBD,GAAQC,EAEV,OAAOD,GCHF,SAASE,IACd,IAAK,IAAID,EAAI,EAAGA,EAAI,GAAIA,IACtBF,ICFG,IAAMI,EAAQ,WACnB,IAAK,IAAIF,EAAI,EAAGA,EAAI,GAAIA,IACtBF,KCDG,SAASK,KACb,WACC,IAAK,IAAIH,EAAI,EAAGA,EAAI,IAAMA,IACxBC,IACAC,IAHH,ICFO,ICAV,WACE,aACEC,IACAC,QAAQC,IAAIC,KAAKC,OAWrB,OARE,YAAAC,IAAA,WACEL,KAGF,sBAAI,oBAAK,C,IAAT,WAEE,OADAA,IACO,G,gCAEX,EAdA,KDCEK,O","file":"typescript-source-map-test.js","sourcesContent":["export const gamma = () => {\n  let prod = 1\n  for (let i = 1; i < 1000; i++) {\n    prod *= i\n  }\n  return prod\n}\n","import {gamma} from './gamma'\n\nexport function beta() {\n  for (let i = 0; i < 10; i++) {\n    gamma()\n  }\n}\n","import {gamma} from './gamma'\n\nexport const delta = function () {\n  for (let i = 0; i < 10; i++) {\n    gamma()\n  }\n}\n","import {beta} from './beta'\nimport {delta} from './delta'\n\nexport function alpha() {\n  ;(function () {\n    for (let i = 0; i < 1000; i++) {\n      beta()\n      delta()\n    }\n  })()\n}\n","import {Kludge} from './kludge'\n\nconst k = new Kludge()\nk.zap()\n","import {alpha} from './alpha'\n\nexport class Kludge {\n  constructor() {\n    alpha()\n    console.log(this.floop)\n  }\n\n  zap() {\n    alpha()\n  }\n\n  get floop(): number {\n    alpha()\n    return 1\n  }\n}\n"],"sourceRoot":""}
@@ -0,0 +1,16 @@
+{
+  "$schema": "https://www.speedscope.app/file-format-schema.json",
+  "shared": {
+    "frames": [{"name": "A"}]
+  },
+  "profiles": [
+    {
+      "type": "evented",
+      "name": "p1",
+      "unit": "none",
+      "startValue": 0,
+      "endValue": 100,
+      "events": [{"type": "O", "frame": 0, "at": 0}]
+    }
+  ]
+}
@@ -0,0 +1,25 @@
+{
+  "$schema": "https://www.speedscope.app/file-format-schema.json",
+  "shared": {
+    "frames": [{"name": "A"}, {"name": "B"}]
+  },
+  "profiles": [
+    {
+      "type": "evented",
+      "name": "p1",
+      "unit": "none",
+      "startValue": 0,
+      "endValue": 100,
+      "events": [
+        {"type": "O", "frame": 0, "at": 0},
+        {"type": "C", "frame": 0, "at": 1},
+        {"type": "O", "frame": 1, "at": 2},
+        {"type": "O", "frame": 0, "at": 2},
+        {"type": "O", "frame": 0, "at": 3},
+        {"type": "C", "frame": 0, "at": 4},
+        {"type": "C", "frame": 1, "at": 4},
+        {"type": "C", "frame": 0, "at": 5}
+      ]
+    }
+  ]
+}
@@ -0,0 +1,25 @@
+[
+  { "pid": 0, "tid": 0, "ph": "B", "ts": 0, "name": "A" },
+  { "pid": 0, "tid": 0, "ph": "E", "ts": 2, "name": "A" },
+  { "pid": 0, "tid": 0, "ph": "X", "ts": 0, "dur": 2, "name": "B" },
+
+  { "pid": 0, "tid": 0, "ph": "X", "ts": 10, "dur": 2, "name": "C" },
+  { "pid": 0, "tid": 0, "ph": "B", "ts": 10, "name": "D" },
+  { "pid": 0, "tid": 0, "ph": "E", "ts": 12, "name": "D" },
+
+  { "pid": 0, "tid": 0, "ph": "X", "ts": 20, "dur": 1, "name": "E" },
+  { "pid": 0, "tid": 0, "ph": "B", "ts": 20, "name": "F" },
+  { "pid": 0, "tid": 0, "ph": "E", "ts": 22, "name": "F" },
+
+  { "pid": 0, "tid": 0, "ph": "B", "ts": 30, "name": "G" },
+  { "pid": 0, "tid": 0, "ph": "E", "ts": 32, "name": "G" },
+  { "pid": 0, "tid": 0, "ph": "X", "ts": 30, "dur": 1, "name": "H" },
+
+  { "pid": 0, "tid": 0, "ph": "X", "ts": 41, "dur": 1, "name": "I" },
+  { "pid": 0, "tid": 0, "ph": "B", "ts": 40, "name": "J" },
+  { "pid": 0, "tid": 0, "ph": "E", "ts": 42, "name": "J" },
+
+  { "pid": 0, "tid": 0, "ph": "B", "ts": 50, "name": "K" },
+  { "pid": 0, "tid": 0, "ph": "E", "ts": 52, "name": "K" },
+  { "pid": 0, "tid": 0, "ph": "X", "ts": 51, "dur": 1, "name": "L" }
+]
@@ -0,0 +1,5 @@
+[
+  {"pid": 0, "tid": 0, "ph": "B", "name": "alpha", "ts": 0},
+  {"pid": 0, "tid": 0, "ph": "E", "name": "alpha", "ts": 1},
+  {"pid": 0, "tid": 0, "ph": "E", "name": "beta", "ts": 2}
+]
@@ -0,0 +1,6 @@
+[
+  {"pid": 0, "tid": 0, "ph": "B", "name": "A", "args": {"x": 1}, "ts": 0},
+  {"pid": 0, "tid": 0, "ph": "B", "name": "B", "args": {"x": 2}, "ts": 1},
+  {"pid": 0, "tid": 0, "ph": "E", "name": "A", "args": {"x": 2}, "ts": 10},
+  {"pid": 0, "tid": 0, "ph": "X", "name": "Z", "args": {"x": 1}, "ts": 10, "dur": 1}
+]
@@ -0,0 +1,7 @@
+[
+  {"tid": 1, "ph": "X", "pid": 0, "name": "alpha", "args": {"x": 0}, "ts": 0, "dur": 10},
+  {"tid": 1, "ph": "B", "pid": 0, "name": "beta", "args": {"x": 0}, "ts": 1},
+  {"tid": 1, "ph": "B", "pid": 0, "name": "gamma", "args": {"x": 0}, "ts": 1},
+  {"tid": 1, "ph": "E", "pid": 0, "name": "beta", "args": {"x": 1}, "ts": 2},
+  {"tid": 1, "ph": "E", "pid": 0, "name": "gamma", "args": {"x": 1}, "ts": 2}
+]
@@ -0,0 +1,4 @@
+[
+  { "pid": 0, "tid": 0, "ph": "X", "ts": 0, "dur": 10, "name": "alpha" },
+  { "pid": 0, "tid": 0, "ph": "X", "ts": 5, "dur": 10, "name": "beta" }
+]
@@ -0,0 +1,7 @@
+[
+  { "pid": 0, "tid": 0, "ph": "X", "ts": 0, "dur": 10, "name": "alpha" },
+  { "pid": 0, "tid": 0, "ph": "X", "ts": 1, "dur": 1, "name": "beta" },
+  { "pid": 0, "tid": 0, "ph": "X", "ts": 1, "dur": 1, "name": "gamma" },
+  { "pid": 0, "tid": 0, "ph": "X", "ts": 5, "dur": 1, "name": "gamma" },
+  { "pid": 0, "tid": 0, "ph": "X", "ts": 5, "dur": 1, "name": "beta" }
+]
@@ -0,0 +1,4 @@
+[
+  {"pid": 0, "tid": 0, "ph": "B", "name": "A", "args": {"x": 1}, "ts": 0},
+  {"pid": 0, "tid": 0, "ph": "E", "name": "A", "args": {"x": 2}, "ts": 10}
+]
@@ -0,0 +1,4 @@
+[
+  {"pid": 0, "tid": 0, "ph": "B", "name": "alpha", "ts": 0},
+  {"pid": 0, "tid": 0, "ph": "E", "name": "beta", "ts": 10}
+]
@@ -0,0 +1,22 @@
+[
+  {"pid": 0, "tid": 0, "ph": "M", "name": "process_name", "args": {"name": "p0"}},
+  {"pid": 0, "tid": 0, "ph": "M", "name": "thread_name", "args": {"name": "p0t0"}},
+  {"pid": 0, "tid": 0, "ph": "X", "name": "alpha", "ts": 0, "dur": 1},
+  {"pid": 0, "tid": 1, "ph": "M", "name": "thread_name", "args": {"name": "p0t1"}},
+  {"pid": 0, "tid": 1, "ph": "X", "name": "beta", "ts": 0, "dur": 1},
+
+  {"pid": 1, "tid": 0, "ph": "M", "name": "process_name", "args": {"name": "p1"}},
+  {"pid": 1, "tid": 0, "ph": "M", "name": "thread_name", "args": {"name": "p1t0"}},
+  {"pid": 1, "tid": 0, "ph": "X", "name": "gamma", "ts": 0, "dur": 1},
+  {"pid": 1, "tid": 1, "ph": "M", "name": "thread_name", "args": {"name": "p1t1"}},
+  {"pid": 1, "tid": 1, "ph": "X", "name": "delta", "ts": 0, "dur": 1},
+
+  {"pid": 2, "tid": 0, "ph": "M", "name": "thread_name", "args": {"name": "p2t0"}},
+  {"pid": 2, "tid": 0, "ph": "X", "name": "epsilon", "ts": 0, "dur": 1},
+  {"pid": 2, "tid": 1, "ph": "M", "name": "thread_name", "args": {"name": "p2t1"}},
+  {"pid": 2, "tid": 1, "ph": "X", "name": "phi", "ts": 0, "dur": 1},
+
+  {"pid": 3, "tid": 0, "ph": "M", "name": "process_name", "args": {"name": "p3"}},
+  {"pid": 3, "tid": 0, "ph": "X", "name": "zeta", "ts": 0, "dur": 1},
+  {"pid": 3, "tid": 1, "ph": "X", "name": "eta", "ts": 0, "dur": 1}
+]
@@ -0,0 +1,16 @@
+[
+  {"tid": 1, "ph": "B", "pid": 0, "name": "A", "ts": 0},
+  {"tid": 1, "ph": "B", "pid": 0, "name": "B", "ts": 0},
+  {"tid": 1, "ph": "B", "pid": 0, "name": "C", "ts": 0},
+  {"tid": 1, "ph": "E", "pid": 0, "name": "C", "ts": 1},
+  {"tid": 1, "ph": "E", "pid": 0, "name": "B", "ts": 2},
+  {"tid": 1, "ph": "E", "pid": 0, "name": "A", "ts": 3},
+  {"tid": 1, "ph": "B", "pid": 0, "name": "A", "ts": 4},
+  {"tid": 1, "ph": "B", "pid": 0, "name": "B", "ts": 5},
+  {"tid": 1, "ph": "B", "pid": 0, "name": "C", "ts": 6},
+  {"tid": 1, "ph": "E", "pid": 0, "name": "C", "ts": 7},
+  {"tid": 1, "ph": "E", "pid": 0, "name": "B", "ts": 7},
+  {"tid": 1, "ph": "E", "pid": 0, "name": "A", "ts": 7},
+  {"tid": 1, "ph": "B", "pid": 0, "name": "X", "ts": 7},
+  {"tid": 1, "ph": "E", "pid": 0, "name": "X", "ts": 10}
+]
@@ -0,0 +1,5 @@
+[
+  {"pid": 0, "tid": 0, "ph": "B", "name": "A", "args": {"x": 1}, "ts": 0},
+  {"pid": 0, "tid": 0, "ph": "B", "name": "A", "args": {"x": 2}, "ts": 1},
+  {"pid": 0, "tid": 0, "ph": "X", "name": "A", "args": {"x": 1}, "ts": 10, "dur": 1}
+]
@@ -0,0 +1,5 @@
+[
+  {"pid": 0, "tid": 0, "ph": "B", "name": "A", "args": {"x": 1}, "ts": 0},
+  {"pid": 0, "tid": 0, "ph": "B", "name": "B", "args": {"x": 2}, "ts": 1},
+  {"pid": 0, "tid": 0, "ph": "B", "name": "C", "args": {"x": 2}, "ts": 2}
+]
@@ -0,0 +1,6 @@
+[
+  {"pid": 0, "tid": 0, "ph": "E", "name": "alpha", "ts": 9},
+  {"pid": 0, "tid": 0, "ph": "E", "name": "beta", "ts": 10},
+  {"pid": 0, "tid": 0, "ph": "B", "name": "alpha", "ts": 0},
+  {"pid": 0, "tid": 0, "ph": "B", "name": "beta", "ts": 1}
+]
@@ -0,0 +1,10 @@
+[
+  {"pid": 0, "tid": 0, "ph": "B", "name": "B", "ts": 1},
+  {"pid": 0, "tid": 0, "ph": "E", "name": "B", "ts": 9},
+
+  {"pid": 0, "tid": 0, "ph": "B", "name": "A", "ts": 0},
+  {"pid": 0, "tid": 0, "ph": "E", "name": "A", "ts": 10},
+
+  {"pid": 0, "tid": 0, "ph": "B", "name": "C", "ts": 2},
+  {"pid": 0, "tid": 0, "ph": "E", "name": "C", "ts": 8}
+]
@@ -0,0 +1,9 @@
+{
+  "traceEvents": [
+    {"pid": 0, "tid": 0, "ph": "B", "name": "alpha", "ts": 0},
+    {"pid": 0, "tid": 0, "ph": "B", "name": "beta", "ts": 1},
+    {"pid": 0, "tid": 0, "ph": "X", "ts": 7, "tdur": 4},
+    {"pid": 0, "tid": 0, "ph": "E", "name": "beta", "ts": 13},
+    {"pid": 0, "tid": 0, "ph": "E", "name": "alpha", "ts": 14}
+  ]
+}
@@ -0,0 +1,7 @@
+[
+  {"pid": 0, "tid": 0, "ph": "B", "name": "alpha", "ts": 0},
+  {"pid": 0, "tid": 0, "ph": "B", "name": "beta", "ts": 1},
+  {"pid": 0, "tid": 0, "ph": "X", "name": "gamma", "ts": 2, "dur": 5, "args": {"detail": "foobar"}},
+  {"pid": 0, "tid": 0, "ph": "X", "name": "epsilon", "ts": 7, "tdur": 4},
+  {"pid": 0, "tid": 0, "ph": "E", "name": "beta", "ts": 13},
+  {"pid": 0, "tid": 0, "ph": "E", "name": "alpha", "ts": 14},
@@ -0,0 +1,13 @@
+
+
+[
+  {"pid": 0, "tid": 0, "ph": "B", "name": "alpha", "ts": 0},
+  {"pid": 0, "tid": 0, "ph": "B", "name": "beta", "ts": 1},
+  {"pid": 0, "tid": 0, "ph": "X", "name": "gamma", "ts": 2, "dur": 5, "args": {"detail": "foobar"}},
+  {"pid": 0, "tid": 0, "ph": "X", "name": "epsilon", "ts": 7, "tdur": 4},
+  {"pid": 0, "tid": 0, "ph": "E", "name": "beta", "ts": 13},
+  {"pid": 0, "tid": 0, "ph": "E", "name": "alpha", "ts": 14},
+
+
+
+
@@ -0,0 +1,7 @@
+[
+  {"pid": 0, "tid": 0, "ph": "B", "name": "alpha", "ts": 0},
+  {"pid": 0, "tid": 0, "ph": "B", "name": "beta", "ts": 1},
+  {"pid": 0, "tid": 0, "ph": "X", "name": "gamma", "ts": 2, "dur": 5, "args": {"detail": "foobar"}},
+  {"pid": 0, "tid": 0, "ph": "X", "name": "epsilon", "ts": 7, "tdur": 4},
+  {"pid": 0, "tid": 0, "ph": "E", "name": "beta", "ts": 13},
+  {"pid": 0, "tid": 0, "ph": "E", "name": "alpha", "ts": 14}
@@ -0,0 +1,8 @@
+[
+  {"pid": 0, "tid": 0, "ph": "B", "name": "alpha", "ts": 0},
+  {"pid": 0, "tid": 0, "ph": "B", "name": "beta", "ts": 1},
+  {"pid": 0, "tid": 0, "ph": "X", "name": "gamma", "ts": 2, "dur": 5, "args": {"detail": "foobar"}},
+  {"pid": 0, "tid": 0, "ph": "X", "name": "epsilon", "ts": 7, "tdur": 4},
+  {"pid": 0, "tid": 0, "ph": "E", "name": "beta", "ts": 13},
+  {"pid": 0, "tid": 0, "ph": "E", "name": "alpha", "ts": 14}
+]
@@ -0,0 +1,8 @@
+[
+  {"pid": 0, "tid": 0, "ph": "B", "name": "alpha", "ts": 0},
+  {"pid": 0, "tid": 0, "ph": "B", "name": "beta", "ts": 1},
+  {"pid": 0, "tid": 0, "ph": "E", "name": "beta", "ts": 13},
+  {"pid": 0, "tid": 0, "ph": "E", "name": "alpha", "ts": 14},
+  {"pid": 0, "tid": 0, "ph": "E", "name": "gamma", "ts": 5},
+  {"pid": 0, "tid": 0, "ph": "E", "name": "delta", "ts": 5}
+]
@@ -0,0 +1,6 @@
+[
+  {"pid": 0, "tid": 0, "ph": "B", "name": "A", "args": {"x": 1}, "ts": 0},
+  {"pid": 0, "tid": 0, "ph": "B", "name": "A", "args": {"x": 2}, "ts": 1},
+  {"pid": 0, "tid": 0, "ph": "E", "name": "A", "args": {"x": 1}, "ts": 9},
+  {"pid": 0, "tid": 0, "ph": "E", "name": "A", "args": {"x": 2}, "ts": 10}
+]
@@ -0,0 +1,6 @@
+[
+  {"pid": 0, "tid": 0, "ph": "B", "name": "alpha", "ts": 0},
+  {"pid": 0, "tid": 0, "ph": "B", "name": "beta", "ts": 1},
+  {"pid": 0, "tid": 0, "ph": "E", "name": "alpha", "ts": 9},
+  {"pid": 0, "tid": 0, "ph": "E", "name": "beta", "ts": 10}
+]
@@ -0,0 +1,15 @@
+[
+  { "pid": 0, "tid": 0, "ph": "X", "ts": 0, "dur": 20, "name": "alpha" },
+
+  { "pid": 0, "tid": 0, "ph": "X", "ts": 1, "dur": 2, "name": "beta" },
+  { "pid": 0, "tid": 0, "ph": "X", "ts": 2, "dur": 1, "name": "gamma" },
+
+  { "pid": 0, "tid": 0, "ph": "X", "ts": 5, "dur": 2, "name": "gamma" },
+  { "pid": 0, "tid": 0, "ph": "X", "ts": 6, "dur": 1, "name": "beta" },
+
+  { "pid": 0, "tid": 0, "ph": "X", "ts": 10, "dur": 1, "name": "gamma" },
+  { "pid": 0, "tid": 0, "ph": "X", "ts": 9, "dur": 2, "name": "beta" },
+
+  { "pid": 0, "tid": 0, "ph": "X", "ts": 15, "dur": 1, "name": "beta" },
+  { "pid": 0, "tid": 0, "ph": "X", "ts": 14, "dur": 2, "name": "gamma" }
+]
@@ -0,0 +1,15 @@
+[
+  { "pid": 0, "tid": 0, "ph": "X", "ts": 0, "dur": 20, "name": "alpha" },
+
+  { "pid": 0, "tid": 0, "ph": "X", "ts": 1, "dur": 2, "name": "beta" },
+  { "pid": 0, "tid": 0, "ph": "X", "ts": 1, "dur": 1, "name": "gamma" },
+
+  { "pid": 0, "tid": 0, "ph": "X", "ts": 5, "dur": 2, "name": "gamma" },
+  { "pid": 0, "tid": 0, "ph": "X", "ts": 5, "dur": 1, "name": "beta" },
+
+  { "pid": 0, "tid": 0, "ph": "X", "ts": 9, "dur": 1, "name": "beta" },
+  { "pid": 0, "tid": 0, "ph": "X", "ts": 9, "dur": 2, "name": "gamma" },
+
+  { "pid": 0, "tid": 0, "ph": "X", "ts": 13, "dur": 1, "name": "gamma" },
+  { "pid": 0, "tid": 0, "ph": "X", "ts": 13, "dur": 2, "name": "beta" }
+]
@@ -0,0 +1,9 @@
+[
+  {"pid": 0, "tid": 0, "ph": "B", "name": "A", "ts": 0},
+  {"pid": 0, "tid": 0, "ph": "B", "name": "B", "ts": 1},
+  {"pid": 0, "tid": 0, "ph": "E", "name": "B", "ts": 1},
+  {"pid": 0, "tid": 0, "ph": "E", "name": "C", "ts": 2},
+  {"pid": 0, "tid": 0, "ph": "B", "name": "C", "ts": 2},
+  {"pid": 0, "tid": 0, "ph": "X", "name": "D", "ts": 3, "dur": 0},
+  {"pid": 0, "tid": 0, "ph": "E", "name": "A", "ts": 10}
+]
@@ -0,0 +1,60 @@
+/*
+* This script is used to reconstruct an cpu profile from chrome with an old format
+* still used in nodejs with v8-profiler
+*/
+const fs = require('fs')
+
+const data = JSON.parse(fs.readFileSync('../../profiles/Chrome/65/simple.cpuprofile').toString())
+
+const _convertTimeDeltas = (profile) => {
+  if (!profile.timeDeltas) return null
+  let lastTimeUsec = profile.startTime
+  const timestamps = new Array(profile.timeDeltas.length + 1)
+  for (let i = 0; i < profile.timeDeltas.length; ++i) {
+    timestamps[i] = lastTimeUsec
+    lastTimeUsec += profile.timeDeltas[i]
+  }
+  timestamps[profile.timeDeltas.length] = lastTimeUsec
+  return timestamps
+}
+
+const reformatNode = node => {
+  if (!node.children) node.children = []
+
+  node.children = node.children.map(childID => {
+    if (typeof childID !== 'number') return childID
+    const childNode = data.nodes.find(node => node.id === childID)
+    if (typeof childNode !== 'object') return null
+    childNode.callUID = node.id
+    return childNode
+  })
+  return {
+    functionName: node.callFrame.functionName,
+    url: node.callFrame.url,
+    lineNumber: node.callFrame.lineNumber,
+    callUID: node.callUID,
+    bailoutReason: '',
+    id: node.id,
+    scriptId: 0,
+    hitCount: node.hitCount,
+    children: node.children.map(reformatNode)
+  }
+}
+
+// reformat then only keep the root as top level node
+const nodes = data.nodes
+  .map(reformatNode)
+  .filter(node => node.functionName === '(root)')[0]
+
+// since it can be undefined, create an array so execution still works
+if (!data.timeDeltas) {
+  data.timeDeltas = []
+}
+
+fs.writeFileSync('./new.cpuprofile', JSON.stringify({
+  head: nodes,
+  startTime: Math.floor(data.startTime / 1000000),
+  endTime: Math.floor(data.endTime / 1000000),
+  samples: data.samples,
+  timestamps: _convertTimeDeltas(data)
+}))
@@ -0,0 +1,22 @@
+## Source Map Test Project
+
+This directory contains test files used to test whether the remapping of
+performance profiles using sourcemaps work correctly.
+
+Run `npm run build` to build the artifacts, then open the appropriate files in
+the `html` directory in whatever browser you're testing.
+
+The idea is to sourcemaps generated by a variety of tools, and also to take
+profiles from a variety of browsers, and hopefully see that they all get 
+remapped as expected.
+
+This project is set up to go through three levels of source-map indirection,
+and also using multiple different build chains.
+
+1. TypeScript -> JavaScript source generation
+2. JavaScript source -> JavaScript bundling
+3. Minification
+
+Some bundlers will swap the order of steps 2 & 3, or potentially merge them,
+but it's complex yet realistic enough that this will hoepfully suss out 
+problems.
@@ -0,0 +1,11 @@
+import {beta} from './beta'
+import {delta} from './delta'
+
+export function alpha() {
+  ;(function () {
+    for (let i = 0; i < 1000; i++) {
+      beta()
+      delta()
+    }
+  })()
+}
@@ -0,0 +1,7 @@
+import {gamma} from './gamma'
+
+export function beta() {
+  for (let i = 0; i < 10; i++) {
+    gamma()
+  }
+}
@@ -0,0 +1,7 @@
+import {gamma} from './gamma'
+
+export const delta = function () {
+  for (let i = 0; i < 10; i++) {
+    gamma()
+  }
+}
@@ -0,0 +1,7 @@
+export const gamma = () => {
+  let prod = 1
+  for (let i = 1; i < 1000; i++) {
+    prod *= i
+  }
+  return prod
+}
@@ -0,0 +1,3 @@
+<title>ESbuild</title>
+<script src="../dist/esbuild/typescript-source-map-test.js"></script>
+<h1>ESbuild Source Map Test</h1>
@@ -0,0 +1,3 @@
+<title>Parcel</title>
+<script src="../dist/parcel/typescript-source-map-test.js"></script>
+<h1>Parcel Source Map Test</h1>
@@ -0,0 +1,3 @@
+<title>Webpack</title>
+<script src="../dist/webpack/typescript-source-map-test.js"></script>
+<h1>Webpack Source Map Test</h1>
@@ -0,0 +1,17 @@
+import {alpha} from './alpha'
+
+export class Kludge {
+  constructor() {
+    alpha()
+    console.log(this.floop)
+  }
+
+  zap() {
+    alpha()
+  }
+
+  get floop(): number {
+    alpha()
+    return 1
+  }
+}
@@ -0,0 +1,23 @@
+{
+  "name": "speedscope-sourcemap-test-project",
+  "version": "1.0.0",
+  "description": "",
+  "private": "true",
+  "main": "index.js",
+  "scripts": {
+    "build": "npm run parcel && npm run webpack && npm run esbuild",
+    "parcel": "parcel build -o parcel/typescript-source-map-test typescript-source-map-test.ts",
+    "webpack": "webpack",
+    "esbuild": "esbuild --sourcemap --minify --bundle --outdir=dist/esbuild typescript-source-map-test.ts"
+  },
+  "author": "",
+  "license": "ISC",
+  "devDependencies": {
+    "esbuild": "^0.7.14",
+    "parcel": "^1.12.4",
+    "ts-loader": "^8.0.4",
+    "typescript": "^4.0.3",
+    "webpack": "^5.0.0",
+    "webpack-cli": "^4.0.0"
+  }
+}
@@ -0,0 +1,10 @@
+{
+  "compilerOptions": {
+    "outDir": "./dist/",
+    "noImplicitAny": true,
+    "sourceMap": true,
+    "module": "es6",
+    "target": "es5",
+    "jsx": "react"
+  }
+}
@@ -0,0 +1,4 @@
+import {Kludge} from './kludge'
+
+const k = new Kludge()
+k.zap()
@@ -0,0 +1,22 @@
+const path = require('path')
+
+module.exports = {
+  entry: './typescript-source-map-test.ts',
+  devtool: 'source-map',
+  module: {
+    rules: [
+      {
+        test: /\.tsx?$/,
+        use: 'ts-loader',
+        exclude: /node_modules/,
+      },
+    ],
+  },
+  resolve: {
+    extensions: ['.tsx', '.ts', '.js'],
+  },
+  output: {
+    filename: 'typescript-source-map-test.js',
+    path: path.resolve(__dirname, 'dist', 'webpack'),
+  },
+}
@@ -0,0 +1,28 @@
+<script>
+  function banana() {
+    let prod = 1
+    for (let i = 1; i < 1000; i++) {
+      prod *= i
+    }
+    return prod
+  }
+
+  function apple() {
+    for (let i = 0; i < 1000; i++) {
+      banana()
+    }
+  }
+
+  let bounces = 0
+
+  const worker = new Worker('./worker.js')
+
+  worker.onmessage = function() {
+    apple()
+    if (bounces++ < 10) {
+      worker.postMessage('ping')
+    }
+  }
+
+  worker.postMessage('ping')
+</script>
@@ -0,0 +1,18 @@
+function gamma() {
+  let prod = 1
+  for (let i = 1; i < 1000; i++) {
+    prod *= i
+  }
+  return prod
+}
+
+function alpha() {
+  for (let i = 0; i < 1000; i++) {
+    gamma()
+  }
+}
+
+onmessage = function(e) {
+  alpha()
+  postMessage('pong')
+}
@@ -0,0 +1,8 @@
+#!/bin/bash
+
+set -euxo pipefail
+
+npm run typecheck
+npm run lint
+npm run coverage
+node scripts/generate-file-format-schema-json.js > /dev/null
@@ -3,7 +3,7 @@ const child_process = require('child_process')

 // Convert the file-format-spec.ts file into a json schema file
 let jsonSchema = child_process.execSync(
-  'node_modules/.bin/quicktype --lang schema ./src/lib/file-format-spec.ts',
+  'node_modules/.bin/typescript-json-schema ./src/lib/file-format-spec.ts --titles --required --topRef "*"',
  {
    encoding: 'utf8',
  },
@@ -24,9 +24,7 @@ export class CanvasContext {
    const webGLInfo = this.gl.getWebGLInfo()
    if (webGLInfo) {
      console.log(
-        `WebGL initialized. renderer: ${webGLInfo.renderer}, vendor: ${
-          webGLInfo.vendor
-        }, version: ${webGLInfo.version}`,
+        `WebGL initialized. renderer: ${webGLInfo.renderer}, vendor: ${webGLInfo.vendor}, version: ${webGLInfo.version}`,
      )
    }
    ;(window as any)['testContextLoss'] = () => {
@@ -175,8 +175,8 @@ export class FlamechartRenderer {
        // and the blue channel to indicate the color bucket to render.
        // We add one to each so we have zero reserved for the background color.
        const color = new Color(
-          (1 + i % 255) / 256,
-          (1 + stackDepth % 255) / 256,
+          (1 + (i % 255)) / 256,
+          (1 + (stackDepth % 255)) / 256,
          (1 + this.flamechart.getColorBucketForFrame(frame.node.frame)) / 256,
        )
        batch.addRect(configSpaceBounds, color)
@@ -288,10 +288,10 @@ export class FlamechartRenderer {
    const configSpaceContentWidth = this.flamechart.getTotalWeight()
    const numAtlasEntriesPerLayer = Math.pow(2, zoomLevel)
    const left = Math.floor(
-      numAtlasEntriesPerLayer * configSpaceSrcRect.left() / configSpaceContentWidth,
+      (numAtlasEntriesPerLayer * configSpaceSrcRect.left()) / configSpaceContentWidth,
    )
    const right = Math.ceil(
-      numAtlasEntriesPerLayer * configSpaceSrcRect.right() / configSpaceContentWidth,
+      (numAtlasEntriesPerLayer * configSpaceSrcRect.right()) / configSpaceContentWidth,
    )

    const nLayers = this.flamechart.getLayers().length
@@ -455,7 +455,8 @@ export namespace WebGL {
      widthInAppUnits: number,
      heightInAppUnits: number,
    ) {
-      const bounds = this._gl.canvas.getBoundingClientRect()
+      let canvas = this._gl.canvas as HTMLCanvasElement
+      const bounds = canvas.getBoundingClientRect()

      if (
        this._width === widthInAppUnits &&
@@ -467,7 +468,6 @@ export namespace WebGL {
        return
      }

-      let canvas = this._gl.canvas
      let style = canvas.style
      canvas.width = widthInPixels
      canvas.height = heightInPixels
@@ -1086,11 +1086,17 @@ export namespace WebGL {

    _compileShader(gl: WebGLRenderingContext, type: GLenum, source: string) {
      let shader = gl.createShader(type)
+      if (!shader) {
+        throw new Error('Failed to create shader')
+      }
      gl.shaderSource(shader, source)
      gl.compileShader(shader)
      if (!gl.getShaderParameter(shader, gl.COMPILE_STATUS)) {
        throw new Error(`${gl.getShaderInfoLog(shader)}`)
      }
+      if (!this._program) {
+        throw new Error('Tried to attach shader before program was created')
+      }
      gl.attachShader(this._program, shader)
    }

@@ -65,7 +65,12 @@ export class ViewportRectangleRenderer {
  private buffer: Graphics.VertexBuffer

  constructor(private gl: Graphics.Context) {
-    const vertices = [[-1, 1], [1, 1], [-1, -1], [1, -1]]
+    const vertices = [
+      [-1, 1],
+      [1, 1],
+      [-1, -1],
+      [1, -1],
+    ]
    const floats: number[] = []
    for (let v of vertices) {
      floats.push(v[0])
@@ -45,7 +45,14 @@ export class RectangleBatch {
      return this.buffer
    }

-    const corners = [[0, 0], [1, 0], [0, 1], [1, 0], [0, 1], [1, 1]]
+    const corners = [
+      [0, 0],
+      [1, 0],
+      [0, 1],
+      [1, 0],
+      [0, 1],
+      [1, 1],
+    ]

    const bytes = new Uint8Array(vertexFormat.stride * corners.length * this.rects.length)
    const floats = new Float32Array(bytes.buffer)
@@ -104,6 +104,114 @@ exports[`importFromBGFlameGraph with CRLF: indexToView 1`] = `0`;

 exports[`importFromBGFlameGraph with CRLF: profileGroup.name 1`] = `"simple-crlf.txt"`;

+exports[`importFromBGFlameGraph with UTF-16, Big Endian 1`] = `
+Object {
+  "frames": Array [
+    Frame {
+      "col": undefined,
+      "file": undefined,
+      "key": "a",
+      "line": undefined,
+      "name": "a",
+      "selfWeight": 0,
+      "totalWeight": 14,
+    },
+    Frame {
+      "col": undefined,
+      "file": undefined,
+      "key": "b",
+      "line": undefined,
+      "name": "b",
+      "selfWeight": 5,
+      "totalWeight": 14,
+    },
+    Frame {
+      "col": undefined,
+      "file": undefined,
+      "key": "c",
+      "line": undefined,
+      "name": "c",
+      "selfWeight": 5,
+      "totalWeight": 5,
+    },
+    Frame {
+      "col": undefined,
+      "file": undefined,
+      "key": "d",
+      "line": undefined,
+      "name": "d",
+      "selfWeight": 4,
+      "totalWeight": 4,
+    },
+  ],
+  "name": "simple-utf16-be.txt",
+  "stacks": Array [
+    "a;b;c 2",
+    "a;b;d 4",
+    "a;b;c 3",
+    "a;b 5",
+  ],
+}
+`;
+
+exports[`importFromBGFlameGraph with UTF-16, Big Endian: indexToView 1`] = `0`;
+
+exports[`importFromBGFlameGraph with UTF-16, Big Endian: profileGroup.name 1`] = `"simple-utf16-be.txt"`;
+
+exports[`importFromBGFlameGraph with UTF-16, Little Endian 1`] = `
+Object {
+  "frames": Array [
+    Frame {
+      "col": undefined,
+      "file": undefined,
+      "key": "a",
+      "line": undefined,
+      "name": "a",
+      "selfWeight": 0,
+      "totalWeight": 14,
+    },
+    Frame {
+      "col": undefined,
+      "file": undefined,
+      "key": "b",
+      "line": undefined,
+      "name": "b",
+      "selfWeight": 5,
+      "totalWeight": 14,
+    },
+    Frame {
+      "col": undefined,
+      "file": undefined,
+      "key": "c",
+      "line": undefined,
+      "name": "c",
+      "selfWeight": 5,
+      "totalWeight": 5,
+    },
+    Frame {
+      "col": undefined,
+      "file": undefined,
+      "key": "d",
+      "line": undefined,
+      "name": "d",
+      "selfWeight": 4,
+      "totalWeight": 4,
+    },
+  ],
+  "name": "simple-utf16-le.txt",
+  "stacks": Array [
+    "a;b;c 2",
+    "a;b;d 4",
+    "a;b;c 3",
+    "a;b 5",
+  ],
+}
+`;
+
+exports[`importFromBGFlameGraph with UTF-16, Little Endian: indexToView 1`] = `0`;
+
+exports[`importFromBGFlameGraph with UTF-16, Little Endian: profileGroup.name 1`] = `"simple-utf16-le.txt"`;
+
 exports[`importFromBGFlameGraph: indexToView 1`] = `0`;

 exports[`importFromBGFlameGraph: profileGroup.name 1`] = `"simple.txt"`;
@@ -64,17 +64,17 @@ exports[`importFromFirefox ignore self-hosted 1`] = `
 Object {
  "frames": Array [
    Frame {
-      "col": undefined,
-      "file": "http://localhost:8000/simple.js:1",
+      "col": 15,
+      "file": "http://localhost:8000/simple.js",
      "key": "alpha (http://localhost:8000/simple.js:1:14)",
-      "line": 14,
+      "line": 1,
      "name": "alpha",
      "selfWeight": 0,
      "totalWeight": 26.983816999942064,
    },
    Frame {
-      "col": undefined,
-      "file": "http://localhost:8000/simple.js:14",
+      "col": 15,
+      "file": "http://localhost:8000/simple.js",
      "key": "delta (http://localhost:8000/simple.js:14:14)",
      "line": 14,
      "name": "delta",
@@ -82,19 +82,19 @@ Object {
      "totalWeight": 11.946324001066387,
    },
    Frame {
-      "col": undefined,
-      "file": "http://localhost:8000/simple.js:20",
+      "col": 15,
+      "file": "http://localhost:8000/simple.js",
      "key": "gamma (http://localhost:8000/simple.js:20:14)",
-      "line": 14,
+      "line": 20,
      "name": "gamma",
      "selfWeight": 26.983816999942064,
      "totalWeight": 26.983816999942064,
    },
    Frame {
-      "col": undefined,
-      "file": "http://localhost:8000/simple.js:8",
+      "col": 14,
+      "file": "http://localhost:8000/simple.js",
      "key": "beta (http://localhost:8000/simple.js:8:13)",
-      "line": 13,
+      "line": 8,
      "name": "beta",
      "selfWeight": 0,
      "totalWeight": 15.037492998875678,
@@ -0,0 +1,101 @@
+// Jest Snapshot v1, https://goo.gl/fbAQLP
+
+exports[`importFromSafari 1`] = `
+Object {
+  "frames": Array [
+    Frame {
+      "col": 13,
+      "file": "__InjectedScript_InjectedScriptSource.js",
+      "key": "injectModule:__InjectedScript_InjectedScriptSource.js:109:13",
+      "line": 109,
+      "name": "injectModule",
+      "selfWeight": 0,
+      "totalWeight": 0.001,
+    },
+    Frame {
+      "col": 10,
+      "file": "__InjectedScript_CommandLineAPIModuleSource.js",
+      "key": ":__InjectedScript_CommandLineAPIModuleSource.js:2:10",
+      "line": 2,
+      "name": "(anonymous)",
+      "selfWeight": 0.001,
+      "totalWeight": 0.001,
+    },
+    Frame {
+      "col": 1,
+      "file": "file:///speedscope/sample/programs/javascript/simple.js",
+      "key": "(program):file:///speedscope/sample/programs/javascript/simple.js:1:1",
+      "line": 1,
+      "name": "(program)",
+      "selfWeight": 0,
+      "totalWeight": 0.03248933597933502,
+    },
+    Frame {
+      "col": 15,
+      "file": "file:///speedscope/sample/programs/javascript/simple.js",
+      "key": "alpha:file:///speedscope/sample/programs/javascript/simple.js:1:15",
+      "line": 1,
+      "name": "alpha",
+      "selfWeight": 0,
+      "totalWeight": 0.03248933597933502,
+    },
+    Frame {
+      "col": 15,
+      "file": "file:///speedscope/sample/programs/javascript/simple.js",
+      "key": "delta:file:///speedscope/sample/programs/javascript/simple.js:14:15",
+      "line": 14,
+      "name": "delta",
+      "selfWeight": 0.003094222474222382,
+      "totalWeight": 0.020112446082445484,
+    },
+    Frame {
+      "col": 15,
+      "file": "file:///speedscope/sample/programs/javascript/simple.js",
+      "key": "gamma:file:///speedscope/sample/programs/javascript/simple.js:20:15",
+      "line": 20,
+      "name": "gamma",
+      "selfWeight": 0.029395113505112636,
+      "totalWeight": 0.029395113505112636,
+    },
+    Frame {
+      "col": 14,
+      "file": "file:///speedscope/sample/programs/javascript/simple.js",
+      "key": "beta:file:///speedscope/sample/programs/javascript/simple.js:8:14",
+      "line": 8,
+      "name": "beta",
+      "selfWeight": 0,
+      "totalWeight": 0.012376889896889526,
+    },
+    Frame {
+      "col": 102,
+      "file": "",
+      "key": "firstOpenSearchURLString::4:102",
+      "line": 4,
+      "name": "firstOpenSearchURLString",
+      "selfWeight": 0.0005174240213818848,
+      "totalWeight": 0.0005174240213818848,
+    },
+  ],
+  "name": "Grabación de Control temporal 1",
+  "stacks": Array [
+    "injectModule;(anonymous) 1.00ms",
+    " 39.93ms",
+    "(program);alpha;delta;gamma 10.83ms",
+    " 2.46ms",
+    "(program);alpha;delta 3.09ms",
+    "(program);alpha;beta;gamma 4.64ms",
+    "(program);alpha;delta;gamma 1.55ms",
+    "(program);alpha;beta;gamma 1.55ms",
+    "(program);alpha;delta;gamma 3.09ms",
+    "(program);alpha;beta;gamma 4.64ms",
+    "(program);alpha;delta;gamma 1.55ms",
+    "(program);alpha;beta;gamma 1.55ms",
+    " 253.50ms",
+    "firstOpenSearchURLString 517.42µs",
+  ],
+}
+`;
+
+exports[`importFromSafari: indexToView 1`] = `0`;
+
+exports[`importFromSafari: profileGroup.name 1`] = `"Grabación de Control temporal 1"`;
@@ -7,3 +7,11 @@ test('importFromBGFlameGraph', async () => {
 test('importFromBGFlameGraph with CRLF', async () => {
  await checkProfileSnapshot('./sample/profiles/stackcollapse/simple-crlf.txt')
 })
+
+test('importFromBGFlameGraph with UTF-16, Little Endian', async () => {
+  await checkProfileSnapshot('./sample/profiles/stackcollapse/simple-utf16-le.txt')
+})
+
+test('importFromBGFlameGraph with UTF-16, Big Endian', async () => {
+  await checkProfileSnapshot('./sample/profiles/stackcollapse/simple-utf16-be.txt')
+})
@@ -11,3 +11,15 @@ test('importFromChromeTimeline', async () => {
 test('importFromChromeTimeline Chrome 69', async () => {
  await checkProfileSnapshot('./sample/profiles/Chrome/69/simple.json')
 })
+
+test('importFromV8Profiler Node 10', async () => {
+  await checkProfileSnapshot('./sample/profiles/node/10.11.0/example.cpuprofile')
+})
+
+test('importFromChromeTimeline Workers Chrome 66', async () => {
+  await checkProfileSnapshot('./sample/profiles/Chrome/66/worker.json')
+})
+
+test('importFromChromeTimeline Workers Chrome 70', async () => {
+  await checkProfileSnapshot('./sample/profiles/Chrome/70/worker.json')
+})
@@ -1,6 +1,7 @@
-import {Profile, FrameInfo, CallTreeProfileBuilder} from '../lib/profile'
-import {getOrInsert, lastOf, sortBy} from '../lib/utils'
+import {Profile, FrameInfo, CallTreeProfileBuilder, ProfileGroup} from '../lib/profile'
+import {getOrInsert, lastOf, sortBy, itForEach} from '../lib/utils'
 import {TimeFormatter} from '../lib/value-formatters'
+import {chromeTreeToNodes, OldCPUProfile} from './v8cpuFormatter'

 // See: https://github.com/v8/v8/blob/master/src/inspector/js_protocol.json

@@ -15,6 +16,7 @@ interface TimelineEvent {
  tdur: number
  tts: number
  args: {[key: string]: any}
+  id?: string
 }

 interface PositionTickInfo {
@@ -30,7 +32,7 @@ interface CPUProfileCallFrame {
  url: string
 }

-interface CPUProfileNode {
+export interface CPUProfileNode {
  callFrame: CPUProfileCallFrame
  hitCount: number
  id: number
@@ -39,7 +41,7 @@ interface CPUProfileNode {
  parent?: CPUProfileNode
 }

-interface CPUProfile {
+export interface CPUProfile {
  startTime: number
  endTime: number
  nodes: CPUProfileNode[]
@@ -61,33 +63,53 @@ export function isChromeTimeline(rawProfile: any): boolean {
  return true
 }

-export function importFromChromeTimeline(events: TimelineEvent[]): Profile {
+export function importFromChromeTimeline(events: TimelineEvent[], fileName: string): ProfileGroup {
  // It seems like sometimes Chrome timeline files contain multiple CpuProfiles?
  // For now, choose the first one in the list.

-  let cpuProfile: CPUProfile | null = null
+  const cpuProfileByID = new Map<string, CPUProfile>()
+
+  // Maps profile IDs (like "0x3") to pid/tid pairs formatted as `${pid}:${tid}`
+  const pidTidById = new Map<string, string>()
+
+  // Maps pid/tid pairs to thread names
+  const threadNameByPidTid = new Map<string, string>()

  // The events aren't necessarily recorded in chronological order. Sort them so
  // that they are.
  sortBy(events, e => e.ts)

  for (let event of events) {
-    if (event.name == 'CpuProfile') {
-      cpuProfile = event.args.data.cpuProfile as CPUProfile
+    if (event.name === 'CpuProfile') {
+      const pidTid = `${event.pid}:${event.tid}`
+      const id = event.id || pidTid
+      cpuProfileByID.set(id, event.args.data.cpuProfile as CPUProfile)
+      pidTidById.set(id, pidTid)
    }

-    if (event.name == 'Profile') {
-      cpuProfile = {
+    if (event.name === 'Profile') {
+      const pidTid = `${event.pid}:${event.tid}`
+      cpuProfileByID.set(event.id || pidTid, {
        startTime: 0,
        endTime: 0,
        nodes: [],
        samples: [],
        timeDeltas: [],
        ...event.args.data,
+      })
+
+      if (event.id) {
+        pidTidById.set(event.id, `${event.pid}:${event.tid}`)
      }
    }

-    if (event.name == 'ProfileChunk') {
+    if (event.name === 'thread_name') {
+      threadNameByPidTid.set(`${event.pid}:${event.tid}`, event.args.name)
+    }
+
+    if (event.name === 'ProfileChunk') {
+      const pidTid = `${event.pid}:${event.tid}`
+      const cpuProfile = cpuProfileByID.get(event.id || pidTid)
      if (cpuProfile) {
        const chunk = event.args.data
        if (chunk.cpuProfile) {
@@ -108,13 +130,36 @@ export function importFromChromeTimeline(events: TimelineEvent[]): Profile {
          cpuProfile.endTime = chunk.endTime
        }
      } else {
-        console.log('Ignoring ProfileChunk when no Profile is active')
+        console.warn(`Ignoring ProfileChunk for undeclared Profile with id ${event.id || pidTid}`)
      }
    }
  }

-  if (cpuProfile) {
-    return importFromChromeCPUProfile(cpuProfile as CPUProfile)
+  if (cpuProfileByID.size > 0) {
+    const profiles: Profile[] = []
+    let indexToView = 0
+
+    itForEach(cpuProfileByID.keys(), profileId => {
+      let threadName: string | null = null
+      let pidTid = pidTidById.get(profileId)
+      if (pidTid) {
+        threadName = threadNameByPidTid.get(pidTid) || null
+        if (threadName) {
+        }
+      }
+      const profile = importFromChromeCPUProfile(cpuProfileByID.get(profileId)!)
+      if (threadName && cpuProfileByID.size > 1) {
+        profile.setName(`${fileName} - ${threadName}`)
+        if (threadName === 'CrRendererMain') {
+          indexToView = profiles.length
+        }
+      } else {
+        profile.setName(`${fileName}`)
+      }
+      profiles.push(profile)
+    })
+
+    return {name: fileName, indexToView, profiles}
  } else {
    throw new Error('Could not find CPU profile in Timeline')
  }
@@ -125,8 +170,17 @@ function frameInfoForCallFrame(callFrame: CPUProfileCallFrame) {
  return getOrInsert(callFrameToFrameInfo, callFrame, callFrame => {
    const name = callFrame.functionName || '(anonymous)'
    const file = callFrame.url
-    const line = callFrame.lineNumber
-    const col = callFrame.columnNumber
+
+    // In Chrome profiles, line numbers & column numbers are both 0-indexed.
+    //
+    // We're going to normalize these to be 1-based to avoid needing to normalize
+    // these at the presentation layer.
+    let line = callFrame.lineNumber
+    if (line != null) line++
+
+    let col = callFrame.columnNumber
+    if (col != null) col++
+
    return {
      key: `${name}:${file}:${line}:${col}`,
      name,
@@ -179,6 +233,10 @@ export function importFromChromeCPUProfile(chromeProfile: CPUProfile): Profile {
  // Ref: https://github.com/v8/v8/blob/44bd8fd7/src/inspector/js_protocol.json#L1485
  let elapsed = chromeProfile.timeDeltas[0]

+  // Prevents negative time deltas from causing bad data. See
+  // https://github.com/jlfwong/speedscope/pull/305 for details.
+  let lastValidElapsed = elapsed
+
  let lastNodeId = NaN

  // The chrome CPU profile format doesn't collapse identical samples. We'll do that
@@ -187,21 +245,26 @@ export function importFromChromeCPUProfile(chromeProfile: CPUProfile): Profile {
    const nodeId = chromeProfile.samples[i]
    if (nodeId != lastNodeId) {
      samples.push(nodeId)
-      sampleTimes.push(elapsed)
+      if (elapsed < lastValidElapsed) {
+        sampleTimes.push(lastValidElapsed)
+      } else {
+        sampleTimes.push(elapsed)
+        lastValidElapsed = elapsed
+      }
    }

    if (i === chromeProfile.samples.length - 1) {
      if (!isNaN(lastNodeId)) {
        samples.push(lastNodeId)
-        sampleTimes.push(elapsed)
+        if (elapsed < lastValidElapsed) {
+          sampleTimes.push(lastValidElapsed)
+        } else {
+          sampleTimes.push(elapsed)
+          lastValidElapsed = elapsed
+        }
      }
    } else {
-      let timeDelta = chromeProfile.timeDeltas[i + 1]
-      if (timeDelta < 0) {
-        console.warn('Substituting zero for unexpected time delta:', timeDelta, 'at index', i)
-        timeDelta = 0
-      }
-
+      const timeDelta = chromeProfile.timeDeltas[i + 1]
      elapsed += timeDelta
      lastNodeId = nodeId
    }
@@ -264,3 +327,7 @@ export function importFromChromeCPUProfile(chromeProfile: CPUProfile): Profile {
  profile.setValueFormatter(new TimeFormatter('microseconds'))
  return profile.build()
 }
+
+export function importFromOldV8CPUProfile(content: OldCPUProfile): Profile {
+  return importFromChromeCPUProfile(chromeTreeToNodes(content))
+}
@@ -176,7 +176,7 @@ export function importFromFirefox(firefoxProfile: FirefoxProfile): Profile {
        const frameData = thread.frameTable.data[f]
        const location = thread.stringTable[frameData[0]]

-        const match = /(.*)\s+\((.*?):?(\d+)?\)$/.exec(location)
+        const match = /(.*)\s+\((.*?)(?::(\d+))?(?::(\d+))?\)$/.exec(location)

        if (!match) return null

@@ -193,7 +193,11 @@ export function importFromFirefox(firefoxProfile: FirefoxProfile): Profile {
          key: location,
          name: match[1]!,
          file: match[2]!,
+
+          // In Firefox profiles, line numbers are 1-based, but columns are
+          // 0-based. Let's normalize both to be 1-based.
          line: match[3] ? parseInt(match[3]) : undefined,
+          col: match[4] ? parseInt(match[4]) + 1 : undefined,
        }))
      })
      .filter(f => f != null) as FrameInfo[]
@@ -5,4 +5,8 @@ test('importProfileGroup', async () => {
  expect(await importProfileGroupFromText('unknown', '')).toBe(null)
  expect(await importProfileGroupFromText('unknown', 'Hello world')).toBe(null)
  expect(await importProfileGroupFromText('unknown', 'Hello\n\nWorld')).toBe(null)
+
+  // Importing from a version of stackprof which was missing raw_timestamp_deltas should return null
+  const oldStackprof = `{"version":1.2,"mode":"wall","interval":1000,"samples":0,"gc_samples":0,"missed_samples":0,"frames":{}}`
+  expect(await importProfileGroupFromText('unknown', oldStackprof)).toBe(null)
 })
@@ -1,7 +1,12 @@
 import {Profile, ProfileGroup} from '../lib/profile'
 import {FileSystemDirectoryEntry} from './file-system-entry'

-import {importFromChromeCPUProfile, importFromChromeTimeline, isChromeTimeline} from './chrome'
+import {
+  importFromChromeCPUProfile,
+  importFromChromeTimeline,
+  isChromeTimeline,
+  importFromOldV8CPUProfile,
+} from './chrome'
 import {importFromStackprof} from './stackprof'
 import {importFromInstrumentsDeepCopy, importFromInstrumentsTrace} from './instruments'
 import {importFromBGFlameGraph} from './bg-flamegraph'
@@ -10,10 +15,12 @@ import {importSpeedscopeProfiles} from '../lib/file-format'
 import {importFromV8ProfLog} from './v8proflog'
 import {importFromLinuxPerf} from './linux-tools-perf'
 import {importFromHaskell} from './haskell'
+import {importFromSafari} from './safari'
 import {ProfileDataSource, TextProfileDataSource, MaybeCompressedDataReader} from './utils'
 import {importAsPprofProfile} from './pprof'
 import {decodeBase64} from '../lib/utils'
 import {importFromChromeHeapProfile} from './v8heapalloc'
+import {isTraceEventFormatted, importTraceEvents} from './trace-event'

 export async function importProfileGroupFromText(
  fileName: string,
@@ -65,6 +72,26 @@ function toGroup(profile: Profile | null): ProfileGroup | null {
  return {name: profile.getName(), indexToView: 0, profiles: [profile]}
 }

+function fixUpJSON(content: string): string {
+  // This code is similar to the code from here:
+  // https://github.com/catapult-project/catapult/blob/27e047e0494df162022be6aa8a8862742a270232/tracing/tracing/extras/importer/trace_event_importer.html#L197-L208
+  //
+  //   If the event data begins with a [, then we know it should end with a ]. The
+  //   reason we check for this is because some tracing implementations cannot
+  //   guarantee that a ']' gets written to the trace file. So, we are forgiving
+  //   and if this is obviously the case, we fix it up before throwing the string
+  //   at JSON.parse.
+  //
+  content = content.trim()
+  if (content[0] === '[') {
+    content = content.replace(/,\s*$/, '')
+    if (content[content.length - 1] !== ']') {
+      content += ']'
+    }
+  }
+  return content
+}
+
 async function _importProfileGroup(dataSource: ProfileDataSource): Promise<ProfileGroup | null> {
  const fileName = await dataSource.name()

@@ -84,12 +111,9 @@ async function _importProfileGroup(dataSource: ProfileDataSource): Promise<Profi
  if (fileName.endsWith('.speedscope.json')) {
    console.log('Importing as speedscope json file')
    return importSpeedscopeProfiles(JSON.parse(contents))
-  } else if (fileName.endsWith('.cpuprofile')) {
-    console.log('Importing as Chrome CPU Profile')
-    return toGroup(importFromChromeCPUProfile(JSON.parse(contents)))
  } else if (fileName.endsWith('.chrome.json') || /Profile-\d{8}T\d{6}/.exec(fileName)) {
    console.log('Importing as Chrome Timeline')
-    return toGroup(importFromChromeTimeline(JSON.parse(contents)))
+    return importFromChromeTimeline(JSON.parse(contents), fileName)
  } else if (fileName.endsWith('.stackprof.json')) {
    console.log('Importing as stackprof profile')
    return toGroup(importFromStackprof(JSON.parse(contents)))
@@ -108,12 +132,15 @@ async function _importProfileGroup(dataSource: ProfileDataSource): Promise<Profi
  } else if (fileName.endsWith('.heapprofile')) {
    console.log('Importing as Chrome Heap Profile')
    return toGroup(importFromChromeHeapProfile(JSON.parse(contents)))
+  } else if (fileName.endsWith('-recording.json')) {
+    console.log('Importing as Safari profile')
+    return toGroup(importFromSafari(JSON.parse(contents)))
  }

  // Second pass: Try to guess what file format it is based on structure
  let parsed: any
  try {
-    parsed = JSON.parse(contents)
+    parsed = JSON.parse(fixUpJSON(contents))
  } catch (e) {}
  if (parsed) {
    if (parsed['$schema'] === 'https://www.speedscope.app/file-format-schema.json') {
@@ -123,12 +150,18 @@ async function _importProfileGroup(dataSource: ProfileDataSource): Promise<Profi
      console.log('Importing as Firefox profile')
      return toGroup(importFromFirefox(parsed))
    } else if (isChromeTimeline(parsed)) {
-      console.log('Importing as Chrome CPU Profile')
-      return toGroup(importFromChromeTimeline(parsed))
-    } else if ('nodes' in parsed && 'samples' in parsed && 'timeDeltas' in parsed) {
      console.log('Importing as Chrome Timeline')
+      return importFromChromeTimeline(parsed, fileName)
+    } else if ('nodes' in parsed && 'samples' in parsed && 'timeDeltas' in parsed) {
+      console.log('Importing as Chrome CPU Profile')
      return toGroup(importFromChromeCPUProfile(parsed))
-    } else if ('mode' in parsed && 'frames' in parsed) {
+    } else if (isTraceEventFormatted(parsed)) {
+      console.log('Importing as Trace Event Format profile')
+      return importTraceEvents(parsed)
+    } else if ('head' in parsed && 'samples' in parsed && 'timestamps' in parsed) {
+      console.log('Importing as Chrome CPU Profile (old format)')
+      return toGroup(importFromOldV8CPUProfile(parsed))
+    } else if ('mode' in parsed && 'frames' in parsed && 'raw_timestamp_deltas' in parsed) {
      console.log('Importing as stackprof profile')
      return toGroup(importFromStackprof(parsed))
    } else if ('code' in parsed && 'functions' in parsed && 'ticks' in parsed) {
@@ -140,6 +173,9 @@ async function _importProfileGroup(dataSource: ProfileDataSource): Promise<Profi
    } else if ('rts_arguments' in parsed && 'initial_capabilities' in parsed) {
      console.log('Importing as Haskell GHC JSON Profile')
      return importFromHaskell(parsed)
+    } else if ('recording' in parsed && 'sampleStackTraces' in parsed.recording) {
+      console.log('Importing as Safari profile')
+      return toGroup(importFromSafari(JSON.parse(contents)))
    }
  } else {
    // Format is not JSON
@@ -98,4 +98,7 @@ describe('importFromInstrumentsTrace', () => {
  test('Instruments 9.3.1', async () => {
    await importFromTrace('./sample/profiles/Instruments/9.3.1/simple-time-profile.trace.zip')
  })
+  test('Instruments 10.0', async () => {
+    await importFromTrace('./sample/profiles/Instruments/10.0/simple-time-profile.trace.zip')
+  })
 })
@@ -361,7 +361,10 @@ async function readFormTemplate(tree: TraceDirectoryTree): Promise<FormTemplateD
  const archive = readInstrumentsKeyedArchive(await readAsArrayBuffer(formTemplate))

  const version = archive['com.apple.xray.owner.template.version']
-  const selectedRunNumber = archive['com.apple.xray.owner.template'].get('_selectedRunNumber')
+  let selectedRunNumber = 1
+  if ('com.apple.xray.owner.template' in archive) {
+    selectedRunNumber = archive['com.apple.xray.owner.template'].get('_selectedRunNumber')
+  }
  let instrument = archive['$1']
  if ('stubInfoByUUID' in archive) {
    instrument = Array.from(archive['stubInfoByUUID'].keys())[0]
@@ -630,7 +633,7 @@ export function readInstrumentsKeyedArchive(buffer: ArrayBuffer): any {
 ////////////////////////////////////////////////////////////////////////////////

 export function decodeUTF8(bytes: Uint8Array): string {
-  let text = String.fromCharCode.apply(String, bytes)
+  let text = String.fromCharCode.apply(String, Array.from(bytes))
  if (text.slice(-1) === '\0') text = text.slice(0, -1) // Remove a single trailing null character if present
  return decodeURIComponent(escape(text))
 }
@@ -737,7 +740,10 @@ function paternMatchObjectiveC(
      // Replace NSString with a string
      case 'NSString':
      case 'NSMutableString':
-        return decodeUTF8(value['NS.bytes'])
+        if (value['NS.string']) return value['NS.string']
+        if (value['NS.bytes']) return decodeUTF8(value['NS.bytes'])
+        console.warn(`Unexpected ${name} format: `, value)
+        return null

      // Replace NSArray with an Array
      case 'NSArray':
@@ -1,6 +1,6 @@
 import {checkProfileSnapshot} from '../lib/test-utils'

-describe('importFromLinuxPerf', async () => {
+describe('importFromLinuxPerf', () => {
  test('simple.linux-perf.txt', async () => {
    await checkProfileSnapshot('./sample/profiles/linux-perf/simple.linux-perf.txt')
  })
@@ -0,0 +1,5 @@
+import {checkProfileSnapshot} from '../lib/test-utils'
+
+test('importFromSafari', async () => {
+  await checkProfileSnapshot('./sample/profiles/Safari/13.1/simple.html-recording.json')
+})
@@ -0,0 +1,120 @@
+import {Profile, FrameInfo, StackListProfileBuilder} from '../lib/profile'
+import {TimeFormatter} from '../lib/value-formatters'
+
+interface Record {
+  type: string
+  eventType?: string
+  startTime?: number
+  endTime?: number
+  // timeline-record-type-cpu
+  timestamp?: number
+  usage?: number
+  threads?: any[]
+  // timeline-record-type-script
+  details?: number | string | any
+  extraDetails?: null | any
+  // timeline-record-type-network
+  archiveStartTime?: number
+  entry?: any
+  // timeline-record-type-layout
+  quad?: number[]
+}
+
+interface ExprLocation {
+  line: number
+  column: number
+}
+
+interface StackFrame {
+  sourceID: string
+  name: string
+  line: number
+  column: number
+  url: string
+  expressionLocation?: ExprLocation
+}
+
+interface Sample {
+  timestamp: number
+  stackFrames: StackFrame[]
+}
+
+interface Recording {
+  displayName: string
+  startTime: number
+  endTime: number
+  discontinuities: any[]
+  instrumentTypes: string[]
+  records: Record[]
+  markers: any[]
+  memoryPressureEvents: any[]
+  sampleStackTraces: Sample[]
+  sampleDurations: number[]
+}
+
+interface Overview {
+  secondsPerPixel: number
+  scrollStartTime: number
+  selectionStartTime: number
+  selectionDuration: number
+}
+
+interface SafariProfile {
+  version: number
+  recording: Recording
+  overview: Overview
+}
+
+function makeStack(frames: StackFrame[]): FrameInfo[] {
+  return frames
+    .map(({name, url, line, column}) => ({
+      key: `${name}:${url}:${line}:${column}`,
+      file: url,
+      line,
+      col: column,
+      name: name || '(anonymous)',
+    }))
+    .reverse()
+}
+
+export function importFromSafari(contents: SafariProfile): Profile | null {
+  if (contents.version !== 1) {
+    console.warn(`Unknown Safari profile version ${contents.version}... Might be incompatible.`)
+  }
+
+  const {recording} = contents
+  const {sampleStackTraces, sampleDurations} = recording
+
+  const count = sampleStackTraces.length
+  if (count < 1) {
+    console.warn('Empty profile')
+    return null
+  }
+
+  const profileDuration =
+    sampleStackTraces[count - 1].timestamp - sampleStackTraces[0].timestamp + sampleDurations[0]
+  const profile = new StackListProfileBuilder(profileDuration)
+
+  let previousEndTime = Number.MAX_VALUE
+
+  sampleStackTraces.forEach((sample, i) => {
+    const endTime = sample.timestamp
+    const duration = sampleDurations[i]
+    const startTime = endTime - duration
+    const idleDurationBefore = startTime - previousEndTime
+
+    // FIXME: 2ms is a lot, but Safari's timestamps and durations don't line up very well and will create
+    // phantom idle time
+    if (idleDurationBefore > 0.002) {
+      profile.appendSampleWithWeight([], idleDurationBefore)
+    }
+
+    profile.appendSampleWithWeight(makeStack(sample.stackFrames), duration)
+
+    previousEndTime = endTime
+  })
+
+  profile.setValueFormatter(new TimeFormatter('seconds'))
+  profile.setName(recording.displayName)
+  return profile.build()
+}
@@ -0,0 +1,101 @@
+import {checkProfileSnapshot} from '../lib/test-utils'
+
+test('importTraceEvents simple', async () => {
+  await checkProfileSnapshot('./sample/profiles/trace-event/simple.json')
+})
+
+test('importTraceEvents simple object', async () => {
+  await checkProfileSnapshot('./sample/profiles/trace-event/simple-object.json')
+})
+
+test('importTraceEvents multiprocess', async () => {
+  await checkProfileSnapshot('./sample/profiles/trace-event/multiprocess.json')
+})
+
+test('importTraceEvents partial json import', async () => {
+  await checkProfileSnapshot('./sample/profiles/trace-event/simple-partial.json')
+})
+
+test('importTraceEvents partial json import trailing comma', async () => {
+  await checkProfileSnapshot('./sample/profiles/trace-event/simple-partial-trailing-comma.json')
+})
+
+test('importTraceEvents partial json import whitespace padding', async () => {
+  await checkProfileSnapshot('./sample/profiles/trace-event/simple-partial-whitespace.json')
+})
+
+test('importTraceEvents bad E events', async () => {
+  await checkProfileSnapshot('./sample/profiles/trace-event/too-many-end-events.json')
+})
+
+test('importTraceEvents event re-ordering', async () => {
+  await checkProfileSnapshot('./sample/profiles/trace-event/must-retain-original-order.json')
+})
+
+test('importTraceEvents end-non-top-of-stack', async () => {
+  await checkProfileSnapshot('./sample/profiles/trace-event/end-non-top-of-stack.json')
+})
+
+test('importTraceEvents mismatched args', async () => {
+  await checkProfileSnapshot('./sample/profiles/trace-event/mismatched-args.json')
+})
+
+test('importTraceEvents mismatched name', async () => {
+  await checkProfileSnapshot('./sample/profiles/trace-event/mismatched-name.json')
+})
+
+test('importTraceEvents not enough end events', async () => {
+  await checkProfileSnapshot('./sample/profiles/trace-event/not-enough-end-events.json')
+})
+
+test('importTraceEvents not out-of-order unbalanced name', async () => {
+  await checkProfileSnapshot('./sample/profiles/trace-event/out-of-order-unbalanced-name.json')
+})
+
+test('importTraceEvents not out-of-order', async () => {
+  await checkProfileSnapshot('./sample/profiles/trace-event/out-of-order.json')
+})
+
+test('importTraceEvents unbalanced name', async () => {
+  await checkProfileSnapshot('./sample/profiles/trace-event/unbalanced-name.json')
+})
+
+test('importTraceEvents unbalanced args', async () => {
+  await checkProfileSnapshot('./sample/profiles/trace-event/unbalanced-args.json')
+})
+
+test('importTraceEvents end event with empty stack', async () => {
+  await checkProfileSnapshot('./sample/profiles/trace-event/end-event-with-empty-stack.json')
+})
+
+test('importTraceEvents only begin events', async () => {
+  await checkProfileSnapshot('./sample/profiles/trace-event/only-begin-events.json')
+})
+
+test('importTraceEvents zero duration events', async () => {
+  await checkProfileSnapshot('./sample/profiles/trace-event/zero-duration-events.json')
+})
+
+test('importTraceEvents matching x', async () => {
+  await checkProfileSnapshot('./sample/profiles/trace-event/matching-x.json')
+})
+
+test('importTraceEvents x events matching start', async () => {
+  await checkProfileSnapshot('./sample/profiles/trace-event/x-events-matching-start.json')
+})
+
+test('importTraceEvents x events matching end', async () => {
+  await checkProfileSnapshot('./sample/profiles/trace-event/x-events-matching-end.json')
+})
+
+test('importTraceEvents BEX interaction', async () => {
+  await checkProfileSnapshot('./sample/profiles/trace-event/bex-interaction.json')
+})
+
+test('importTraceEvents invalid x nesting', async () => {
+  await checkProfileSnapshot('./sample/profiles/trace-event/invalid-x-nesting.json')
+})
+
+test('importTraceEvents event reordering name match', async () => {
+  await checkProfileSnapshot('./sample/profiles/trace-event/event-reordering-name-match.json')
+})
@@ -0,0 +1,486 @@
+import {sortBy, zeroPad, getOrInsert, lastOf} from '../lib/utils'
+import {ProfileGroup, CallTreeProfileBuilder, FrameInfo, Profile} from '../lib/profile'
+import {TimeFormatter} from '../lib/value-formatters'
+
+// This file concerns import from the "Trace Event Format", authored by Google
+// and used for Google's own chrome://trace.
+//
+// The file format is extremely general, and we only support the parts of it
+// that logically map onto speedscope's visualization capabilities.
+// Specifically, we only support the "B", "E", and "X" event types. Everything
+// else is ignored. We do, however, support import of profiles that are
+// multi-process/multi-threaded. Each process is split into a separate profile.
+//
+// Note that Chrome Developer Tools uses this format as well, but all the
+// relevant data used in those profiles is stored in events with the name
+// "CpuProfile", "Profile", or "ProfileChunk". If we detect those, we prioritize
+// importing the profile as a Chrome Developer Tools profile. Otherwise,
+// we try to import it as a "Trace Event Format" file.
+//
+// Spec: https://docs.google.com/document/d/1CvAClvFfyA5R-PhYUmn5OOQtYMH4h6I0nSsKchNAySU/preview
+
+interface TraceEvent {
+  // The process ID for the process that output this event.
+  pid: number
+
+  // The thread ID for the thread that output this event.
+  tid: number
+
+  // The event type. This is a single character which changes depending on the type of event being output. The valid values are listed in the table below. We will discuss each phase type below.
+  ph: string
+
+  // The tracing clock timestamp of the event. The timestamps are provided at microsecond granularity.
+  ts: number
+
+  // The thread clock timestamp of the event. The timestamps are provided at microsecond granularity.
+  tts?: number
+
+  // The name of the event, as displayed in Trace Viewer
+  name?: string
+
+  // The event categories. This is a comma separated list of categories for the event. The categories can be used to hide events in the Trace Viewer UI.
+  cat?: string
+
+  // Any arguments provided for the event. Some of the event types have required argument fields, otherwise, you can put any information you wish in here. The arguments are displayed in Trace Viewer when you view an event in the analysis section.
+  args: any
+
+  // A fixed color name to associate with the event. If provided, cname must be one of the names listed in trace-viewer's base color scheme's reserved color names list
+  cname?: string
+}
+
+interface BTraceEvent extends TraceEvent {
+  ph: 'B'
+}
+
+interface ETraceEvent extends TraceEvent {
+  ph: 'E'
+}
+
+interface XTraceEvent extends TraceEvent {
+  ph: 'X'
+  dur?: number
+  tdur?: number
+}
+
+// The trace format supports a number of event types that we ignore.
+type ImportableTraceEvent = BTraceEvent | ETraceEvent | XTraceEvent
+
+function pidTidKey(pid: number, tid: number): string {
+  // We zero-pad the PID and TID to make sorting them by pid/tid pair later easier.
+  return `${zeroPad('' + pid, 10)}:${zeroPad('' + tid, 10)}`
+}
+
+function partitionByPidTid(events: ImportableTraceEvent[]): Map<string, ImportableTraceEvent[]> {
+  const map = new Map<string, ImportableTraceEvent[]>()
+
+  for (let ev of events) {
+    const list = getOrInsert(map, pidTidKey(ev.pid, ev.tid), () => [])
+    list.push(ev)
+  }
+
+  return map
+}
+
+function selectQueueToTakeFromNext(
+  bEventQueue: BTraceEvent[],
+  eEventQueue: ETraceEvent[],
+): 'B' | 'E' {
+  if (bEventQueue.length === 0 && eEventQueue.length === 0) {
+    throw new Error('This method should not be given both queues empty')
+  }
+  if (eEventQueue.length === 0) return 'B'
+  if (bEventQueue.length === 0) return 'E'
+
+  const bFront = bEventQueue[0]
+  const eFront = eEventQueue[0]
+
+  const bts = bFront.ts
+  const ets = eFront.ts
+
+  if (bts < ets) return 'B'
+  if (ets < bts) return 'E'
+
+  // If we got here, the 'B' event queue and the 'E' event queue have events at
+  // the front with equal timestamps.
+
+  // If the front of the 'E' queue matches the front of the 'B' queue by name,
+  // then it means we have a zero duration event. Process the 'B' queue first
+  // to ensure it opens before we try to close it.
+  //
+  // Otherwise, process the 'E' queue first.
+  return bFront.name === eFront.name ? 'B' : 'E'
+}
+
+function convertToEventQueues(events: ImportableTraceEvent[]): [BTraceEvent[], ETraceEvent[]] {
+  const beginEvents: BTraceEvent[] = []
+  const endEvents: ETraceEvent[] = []
+
+  // Rebase all of the timestamps on the lowest timestamp
+  if (events.length > 0) {
+    let firstTs = Number.MAX_SAFE_INTEGER
+    for (let ev of events) {
+      firstTs = Math.min(firstTs, ev.ts)
+    }
+    for (let ev of events) {
+      ev.ts -= firstTs
+    }
+  }
+
+  // Next, combine B, E, and X events into two timestamp ordered queues.
+  const xEvents: XTraceEvent[] = []
+  for (let ev of events) {
+    switch (ev.ph) {
+      case 'B': {
+        beginEvents.push(ev)
+        break
+      }
+
+      case 'E': {
+        endEvents.push(ev)
+        break
+      }
+
+      case 'X': {
+        xEvents.push(ev)
+        break
+      }
+
+      default: {
+        const _exhaustiveCheck: never = ev
+        return _exhaustiveCheck
+      }
+    }
+  }
+
+  function dur(x: XTraceEvent): number {
+    return x.dur ?? x.tdur ?? 0
+  }
+
+  xEvents.sort((a, b) => {
+    if (a.ts < b.ts) return -1
+    if (a.ts > b.ts) return 1
+
+    // Super weird special case: if we have two 'X' events with the same 'ts'
+    // but different 'dur' the only valid interpretation is to put the one with
+    // the longer 'dur' first, because you can't nest longer things in shorter
+    // things.
+    const aDur = dur(a)
+    const bDur = dur(b)
+    if (aDur > bDur) return -1
+    if (aDur < bDur) return 1
+
+    // Otherwise, retain the original order by relying upon a stable sort here.
+    return 0
+  })
+
+  for (let x of xEvents) {
+    const xDur = dur(x)
+    beginEvents.push({...x, ph: 'B'} as BTraceEvent)
+    endEvents.push({...x, ph: 'E', ts: x.ts + xDur} as ETraceEvent)
+  }
+
+  function compareTimestamps(a: TraceEvent, b: TraceEvent) {
+    if (a.ts < b.ts) return -1
+    if (a.ts > b.ts) return 1
+
+    // Important: if the timestamps are the same, return zero. We're going to
+    // rely upon a stable sort here.
+    return 0
+  }
+
+  beginEvents.sort(compareTimestamps)
+  endEvents.sort(compareTimestamps)
+
+  return [beginEvents, endEvents]
+}
+
+function filterIgnoredEventTypes(events: TraceEvent[]): ImportableTraceEvent[] {
+  const ret: ImportableTraceEvent[] = []
+  for (let ev of events) {
+    switch (ev.ph) {
+      case 'B':
+      case 'E':
+      case 'X':
+        ret.push(ev as ImportableTraceEvent)
+    }
+  }
+  return ret
+}
+
+function getProcessNamesByPid(events: TraceEvent[]): Map<number, string> {
+  const processNamesByPid = new Map<number, string>()
+  for (let ev of events) {
+    if (ev.ph === 'M' && ev.name === 'process_name' && ev.args && ev.args.name) {
+      processNamesByPid.set(ev.pid, ev.args.name)
+    }
+  }
+  return processNamesByPid
+}
+
+function getThreadNamesByPidTid(events: TraceEvent[]): Map<string, string> {
+  const threadNameByPidTid = new Map<string, string>()
+
+  for (let ev of events) {
+    if (ev.ph === 'M' && ev.name === 'thread_name' && ev.args && ev.args.name) {
+      threadNameByPidTid.set(pidTidKey(ev.pid, ev.tid), ev.args.name)
+    }
+  }
+  return threadNameByPidTid
+}
+
+function keyForEvent(event: TraceEvent): string {
+  let name = `${event.name || '(unnamed)'}`
+  if (event.args) {
+    name += ` ${JSON.stringify(event.args)}`
+  }
+  return name
+}
+
+function frameInfoForEvent(event: TraceEvent): FrameInfo {
+  const key = keyForEvent(event)
+  return {
+    name: key,
+    key: key,
+  }
+}
+
+function eventListToProfileGroup(events: TraceEvent[]): ProfileGroup {
+  const importableEvents = filterIgnoredEventTypes(events)
+  const partitioned = partitionByPidTid(importableEvents)
+
+  const processNamesByPid = getProcessNamesByPid(events)
+  const threadNamesByPidTid = getThreadNamesByPidTid(events)
+
+  const profilePairs: [string, Profile][] = []
+
+  partitioned.forEach(eventsForThread => {
+    if (eventsForThread.length === 0) return
+
+    const {pid, tid} = eventsForThread[0]
+
+    const profile = new CallTreeProfileBuilder()
+    profile.setValueFormatter(new TimeFormatter('microseconds'))
+
+    const processName = processNamesByPid.get(pid)
+    const threadName = threadNamesByPidTid.get(pidTidKey(pid, tid))
+
+    if (processName != null && threadName != null) {
+      profile.setName(`${processName} (pid ${pid}), ${threadName} (tid ${tid})`)
+    } else if (processName != null) {
+      profile.setName(`${processName} (pid ${pid}, tid ${tid})`)
+    } else if (threadName != null) {
+      profile.setName(`${threadName} (pid ${pid}, tid ${tid})`)
+    } else {
+      profile.setName(`pid ${pid}, tid ${tid}`)
+    }
+
+    // The trace event format is hard to deal with because it specifically
+    // allows events to be recorded out of order, *but* event ordering is still
+    // important for events with the same timestamp. Because of this, rather
+    // than thinking about the entire event stream as a single queue of events,
+    // we're going to first construct two time-ordered lists of events:
+    //
+    // 1. ts ordered queue of 'B' events
+    // 2. ts ordered queue of 'E' events
+    //
+    // We deal with 'X' events by converting them to one entry in the 'B' event
+    // queue and one entry in the 'E' event queue.
+    //
+    // The high level goal is to deal with 'B' events in 'ts' order, breaking
+    // ties by the order the events occurred in the file, and deal with 'E'
+    // events in 'ts' order, breaking ties in whatever order causes the 'E'
+    // events to match whatever is on the top of the stack.
+    const [bEventQueue, eEventQueue] = convertToEventQueues(eventsForThread)
+
+    const frameStack: BTraceEvent[] = []
+    const enterFrame = (b: BTraceEvent) => {
+      frameStack.push(b)
+      profile.enterFrame(frameInfoForEvent(b), b.ts)
+    }
+
+    const tryToLeaveFrame = (e: ETraceEvent) => {
+      const b = lastOf(frameStack)
+
+      if (b == null) {
+        console.warn(
+          `Tried to end frame "${
+            frameInfoForEvent(e).key
+          }", but the stack was empty. Doing nothing instead.`,
+        )
+        return
+      }
+
+      const eFrameInfo = frameInfoForEvent(e)
+      const bFrameInfo = frameInfoForEvent(b)
+
+      if (e.name !== b.name) {
+        console.warn(
+          `ts=${e.ts}: Tried to end "${eFrameInfo.key}" when "${bFrameInfo.key}" was on the top of the stack. Doing nothing instead.`,
+        )
+        return
+      }
+
+      if (eFrameInfo.key !== bFrameInfo.key) {
+        console.warn(
+          `ts=${e.ts}: Tried to end "${eFrameInfo.key}" when "${bFrameInfo.key}" was on the top of the stack. Ending ${bFrameInfo.key} instead.`,
+        )
+      }
+
+      frameStack.pop()
+      profile.leaveFrame(bFrameInfo, e.ts)
+    }
+
+    while (bEventQueue.length > 0 || eEventQueue.length > 0) {
+      const queueName = selectQueueToTakeFromNext(bEventQueue, eEventQueue)
+      switch (queueName) {
+        case 'B': {
+          enterFrame(bEventQueue.shift()!)
+          break
+        }
+        case 'E': {
+          // Before we take the first event in the 'E' queue, let's first see if
+          // there are any e events that exactly match the top of the stack.
+          // We'll prioritize first by key, then by name if we can't find a key
+          // match.
+          const stackTop = lastOf(frameStack)
+          if (stackTop != null) {
+            const bFrameInfo = frameInfoForEvent(stackTop)
+
+            let swapped: boolean = false
+
+            for (let i = 1; i < eEventQueue.length; i++) {
+              const eEvent = eEventQueue[i]
+              if (eEvent.ts > eEventQueue[0].ts) {
+                // Only consider 'E' events with the same ts as the front of the queue.
+                break
+              }
+
+              const eFrameInfo = frameInfoForEvent(eEvent)
+              if (bFrameInfo.key === eFrameInfo.key) {
+                // We have a match! Process this one first.
+                const temp = eEventQueue[0]
+                eEventQueue[0] = eEventQueue[i]
+                eEventQueue[i] = temp
+                swapped = true
+                break
+              }
+            }
+
+            if (!swapped) {
+              // There was no key match, let's see if we can find a name match
+              for (let i = 1; i < eEventQueue.length; i++) {
+                const eEvent = eEventQueue[i]
+                if (eEvent.ts > eEventQueue[0].ts) {
+                  // Only consider 'E' events with the same ts as the front of the queue.
+                  break
+                }
+
+                if (eEvent.name === stackTop.name) {
+                  // We have a match! Process this one first.
+                  const temp = eEventQueue[0]
+                  eEventQueue[0] = eEventQueue[i]
+                  eEventQueue[i] = temp
+                  swapped = true
+                  break
+                }
+              }
+            }
+
+            // If swapped is still false at this point, it means we're about to
+            // pop a stack frame that doesn't even match by name. Bummer.
+          }
+
+          const e = eEventQueue.shift()!
+
+          tryToLeaveFrame(e)
+          break
+        }
+
+        default:
+          const _exhaustiveCheck: never = queueName
+          return _exhaustiveCheck
+      }
+    }
+
+    for (let i = frameStack.length - 1; i >= 0; i--) {
+      const frame = frameInfoForEvent(frameStack[i])
+      console.warn(`Frame "${frame.key}" was still open at end of profile. Closing automatically.`)
+      profile.leaveFrame(frame, profile.getTotalWeight())
+    }
+
+    profilePairs.push([pidTidKey(pid, tid), profile.build()])
+  })
+
+  // For now, we just sort processes by pid & tid.
+  // TODO: The standard specifies that metadata events with the name
+  // "process_sort_index" and "thread_sort_index" can be used to influence the
+  // order, but for simplicity we'll ignore that until someone complains :)
+  sortBy(profilePairs, p => p[0])
+
+  return {
+    name: '',
+    indexToView: 0,
+    profiles: profilePairs.map(p => p[1]),
+  }
+}
+
+function isTraceEventList(maybeEventList: any): maybeEventList is TraceEvent[] {
+  if (!Array.isArray(maybeEventList)) return false
+  if (maybeEventList.length === 0) return false
+
+  // Both ph and ts should be provided for every event. In theory, many other
+  // fields are mandatory, but without these fields, we won't usefully be able
+  // to import the data, so we'll rely upon these.
+  for (let el of maybeEventList) {
+    if (!('ph' in el)) {
+      return false
+    }
+
+    switch (el.ph) {
+      case 'B':
+      case 'E':
+      case 'X':
+        // All B, E, and X events must have a timestamp specified, otherwise we
+        // won't be able to import correctly.
+        if (!('ts' in el)) {
+          return false
+        }
+
+      case 'M':
+        // It's explicitly okay for "M" (metadata) events not to specify a "ts"
+        // field, since usually there is no logical timestamp for them to have
+        break
+    }
+  }
+
+  return true
+}
+
+function isTraceEventObject(
+  maybeTraceEventObject: any,
+): maybeTraceEventObject is {traceEvents: TraceEvent[]} {
+  if (!('traceEvents' in maybeTraceEventObject)) return false
+  return isTraceEventList(maybeTraceEventObject['traceEvents'])
+}
+
+export function isTraceEventFormatted(
+  rawProfile: any,
+): rawProfile is {traceEvents: TraceEvent[]} | TraceEvent[] {
+  // We're only going to support the JSON formatted profiles for now.
+  // The spec also discusses support for data embedded in ftrace supported data: https://lwn.net/Articles/365835/.
+
+  return isTraceEventObject(rawProfile) || isTraceEventList(rawProfile)
+}
+
+export function importTraceEvents(
+  rawProfile: {traceEvents: TraceEvent[]} | TraceEvent[],
+): ProfileGroup {
+  if (isTraceEventObject(rawProfile)) {
+    return eventListToProfileGroup(rawProfile.traceEvents)
+  } else if (isTraceEventList(rawProfile)) {
+    return eventListToProfileGroup(rawProfile)
+  } else {
+    const _exhaustiveCheck: never = rawProfile
+    return _exhaustiveCheck
+  }
+}
@@ -51,15 +51,30 @@ export class MaybeCompressedDataReader implements ProfileDataSource {

  async readAsText(): Promise<string> {
    const buffer = await this.readAsArrayBuffer()
-    let ret: string = ''
+
+    // By default, we assume the file is utf-8 encoded.
+    let encoding = 'utf-8'
+
+    const array = new Uint8Array(buffer)
+    if (array.length > 2) {
+      if (array[0] === 0xff && array[1] === 0xfe) {
+        // UTF-16, Little Endian encoding
+        encoding = 'utf-16le'
+      } else if (array[0] === 0xfe && array[1] === 0xff) {
+        // UTF-16, Big Endian encoding
+        encoding = 'utf-16be'
+      }
+    }

    if (typeof TextDecoder !== 'undefined') {
-      const decoder = new TextDecoder()
+      const decoder = new TextDecoder(encoding)
      return decoder.decode(buffer)
    } else {
-      // JavaScript strings are UTF-16 encoded, but we're reading data
-      // from disk that we're going to asusme is UTF-8 encoded.
-      const array = new Uint8Array(buffer)
+      // JavaScript strings are UTF-16 encoded, but we're reading data from disk
+      // that we're going to blindly assume it's ASCII encoded. This codepath
+      // only exists for older browser support.
+      console.warn('This browser does not support TextDecoder. Decoding text as ASCII.')
+      let ret: string = ''
      for (let i = 0; i < array.length; i++) {
        ret += String.fromCharCode(array[i])
      }
@@ -0,0 +1,71 @@
+import {CPUProfile, CPUProfileNode} from './chrome'
+
+/**
+ * This importer handles an old format used by the C++ API of V8. This format is still used by v8-profiler-node8.
+ * There are two differences between the two formats:
+ *  - Nodes are a tree in the old format and a flat array in the new format
+ *  - Weights are timestamps in the old format and deltas in the new format.
+ *
+ * For more information, see https://github.com/hyj1991/v8-profiler-node8
+ */
+
+interface OldCPUProfileNode {
+  functionName: string
+  lineNumber: number
+  scriptId: string
+  url: string
+  hitCount: number
+  bailoutReason: string
+  id: number
+  children: OldCPUProfileNode[]
+}
+
+export interface OldCPUProfile {
+  startTime: number
+  endTime: number
+  head: OldCPUProfileNode
+  samples: number[]
+  timestamps: number[]
+}
+
+function treeToArray(root: OldCPUProfileNode): CPUProfileNode[] {
+  const nodes: CPUProfileNode[] = []
+  function visit(node: OldCPUProfileNode) {
+    nodes.push({
+      id: node.id,
+      callFrame: {
+        columnNumber: 0,
+        functionName: node.functionName,
+        lineNumber: node.lineNumber,
+        scriptId: node.scriptId,
+        url: node.url,
+      },
+      hitCount: node.hitCount,
+      children: node.children.map(child => child.id),
+    })
+    node.children.forEach(visit)
+  }
+  visit(root)
+  return nodes
+}
+
+function timestampsToDeltas(timestamps: number[], startTime: number): number[] {
+  return timestamps.map((timestamp, index) => {
+    const lastTimestamp = index === 0 ? startTime * 1000000 : timestamps[index - 1]
+    return timestamp - lastTimestamp
+  })
+}
+
+/**
+ * Convert the old tree-based format to the new flat-array based format
+ */
+export function chromeTreeToNodes(content: OldCPUProfile): CPUProfile {
+  // Note that both startTime and endTime are now in microseconds
+  return {
+    samples: content.samples,
+    startTime: content.startTime * 1000000,
+    endTime: content.endTime * 1000000,
+    nodes: treeToArray(content.head),
+    timeDeltas: timestampsToDeltas(content.timestamps, content.startTime),
+  }
+}
@@ -0,0 +1,57 @@
+// Versions of node before 10 had an unstable sort. This isn't really an issue in browsers
+// that speedscope supports, but for the purposes of supporting node 10, we'll polyfill
+// a stable sort to make the tests pass.
+//
+// See:
+// - https://v8.dev/features/stable-sort
+// - https://v8.dev/blog/array-sort
+// - https://github.com/jlfwong/speedscope/pull/254#issuecomment-575116995
+//
+// Once we stop supporting node 10, this can be removed.
+//
+// An alternative would be to change our sort implementation to be stable by definition
+// rather than relying upon native sort being stable. I don't want to do that because
+// we'd take a perf hit.
+//
+// Because we're not going to use this in our actual build, it's okay for this
+// to be inefficient.
+
+;(function () {
+  const nodeVersion = process.versions.node
+  const versionParts = nodeVersion.split('.')
+  const majorVersion = parseInt(versionParts[0], 10)
+
+  if (majorVersion > 10) {
+    // Don't need to do the patch for newer node versions
+    return
+  }
+
+  const defaultCompareFunction = (a, b) => {
+    const sa = '' + a
+    const sb = '' + b
+    if (sa < sb) return -1
+    if (sa > sb) return 1
+    return 0
+  }
+
+  const originalSort = Array.prototype.sort
+  Array.prototype.sort = function (compareFunction) {
+    const arrayWithIndices = this.map((x, i) => [x, i])
+    originalSort.call(arrayWithIndices, (a, b) => {
+      if (!compareFunction) {
+        compareFunction = defaultCompareFunction
+      }
+      const res = compareFunction(a[0], b[0])
+      if (res !== 0) return res
+      return a[1] < b[1] ? -1 : 1
+    })
+    this.splice(0, this.length, ...arrayWithIndices.map(x => x[0]))
+    return this
+  }
+})()
+;(function () {
+  // TextDecoder is a global API in browsers, but an imported API in node.
+  //
+  // Let's emulate it being a global API during tests.
+  global.TextDecoder = require('util').TextDecoder
+})()
@@ -211,3 +211,7 @@ Object {
 exports[`importSpeedscopeProfiles 0.6.0 multiple profiles: indexToView 1`] = `1`;

 exports[`importSpeedscopeProfiles 0.6.0 multiple profiles: profileGroup.name 1`] = `"Two Samples"`;
+
+exports[`importSpeedscopeProfiles invalid due to incomplete trace 1`] = `"Tried to complete profile construction with a non-empty stack"`;
+
+exports[`importSpeedscopeProfiles invalid due to out of order events 1`] = `"Tried to leave frame \\"B\\" while frame \\"A\\" was at the top at 4"`;
@@ -0,0 +1,70 @@
+// Jest Snapshot v1, https://goo.gl/fbAQLP
+
+exports[`source-map remapping of chrome-85-esbuild 1`] = `
+Array [
+  "((anonymous) @ alpha.ts:5:5) <- ((anonymous) @ file:///Users/jlfwong/code/speedscope/sample/programs/javascript/sourcemaps/dist/esbuild/typescript-source-map-test.js:1:170)",
+  "(e @ beta.ts:3:8) <- (e @ file:///Users/jlfwong/code/speedscope/sample/programs/javascript/sourcemaps/dist/esbuild/typescript-source-map-test.js:1:75)",
+  "(get floop @ kludge.ts:13:7) <- (get floop @ file:///Users/jlfwong/code/speedscope/sample/programs/javascript/sourcemaps/dist/esbuild/typescript-source-map-test.js:1:276)",
+  "(l constructor @ kludge.ts:4:3) <- (l @ file:///Users/jlfwong/code/speedscope/sample/programs/javascript/sourcemaps/dist/esbuild/typescript-source-map-test.js:1:226)",
+  "(m @ delta.ts:3:22) <- (m @ file:///Users/jlfwong/code/speedscope/sample/programs/javascript/sourcemaps/dist/esbuild/typescript-source-map-test.js:1:119)",
+  "(r @ alpha.ts:4:8) <- (r @ file:///Users/jlfwong/code/speedscope/sample/programs/javascript/sourcemaps/dist/esbuild/typescript-source-map-test.js:1:158)",
+  "(gamma @ gamma.ts:1:14) <- (t @ file:///Users/jlfwong/code/speedscope/sample/programs/javascript/sourcemaps/dist/esbuild/typescript-source-map-test.js:1:15)",
+  "(zap @ kludge.ts:9:3) <- (zap @ file:///Users/jlfwong/code/speedscope/sample/programs/javascript/sourcemaps/dist/esbuild/typescript-source-map-test.js:1:260)",
+]
+`;
+
+exports[`source-map remapping of chrome-85-parcel 1`] = `
+Array [
+  "((anonymous) @ ../alpha.ts:5:5) <- ((anonymous) @ file:///Users/jlfwong/code/speedscope/sample/programs/javascript/sourcemaps/dist/parcel/typescript-source-map-test.js:8:152)",
+  "(e @ ../gamma.ts:1:22) <- (e @ file:///Users/jlfwong/code/speedscope/sample/programs/javascript/sourcemaps/dist/parcel/typescript-source-map-test.js:2:104)",
+  "(get @ ../kludge.ts:13:3) <- (get @ file:///Users/jlfwong/code/speedscope/sample/programs/javascript/sourcemaps/dist/parcel/typescript-source-map-test.js:10:284)",
+  "(o.zap @ ../kludge.ts:9:3) <- (o.zap @ file:///Users/jlfwong/code/speedscope/sample/programs/javascript/sourcemaps/dist/parcel/typescript-source-map-test.js:10:211)",
+  "(o constructor @ ../kludge.ts:4:3) <- (o @ file:///Users/jlfwong/code/speedscope/sample/programs/javascript/sourcemaps/dist/parcel/typescript-source-map-test.js:10:139)",
+  "(parcelRequire.CIJJ../alpha @ ../alpha.ts:5:5) <- (parcelRequire.CIJJ../alpha @ file:///Users/jlfwong/code/speedscope/sample/programs/javascript/sourcemaps/dist/parcel/typescript-source-map-test.js:9:55)",
+  "(parcelRequire.EJAe../gamma @ ../gamma.ts:1:8) <- (parcelRequire.EJAe../gamma @ file:///Users/jlfwong/code/speedscope/sample/programs/javascript/sourcemaps/dist/parcel/typescript-source-map-test.js:3:23)",
+  "(parcelRequire.NDR3../beta @ ../delta.ts:3:8) <- (parcelRequire.NDR3../beta @ file:///Users/jlfwong/code/speedscope/sample/programs/javascript/sourcemaps/dist/parcel/typescript-source-map-test.js:7:39)",
+  "(parcelRequire.xEzo../kludge @ ../kludge.ts:3:1) <- (parcelRequire.xEzo../kludge @ file:///Users/jlfwong/code/speedscope/sample/programs/javascript/sourcemaps/dist/parcel/typescript-source-map-test.js:11:39)",
+  "(beta @ ../beta.ts:3:17) <- (r @ file:///Users/jlfwong/code/speedscope/sample/programs/javascript/sourcemaps/dist/parcel/typescript-source-map-test.js:4:119)",
+  "(r @ ../delta.ts:3:22) <- (r @ file:///Users/jlfwong/code/speedscope/sample/programs/javascript/sourcemaps/dist/parcel/typescript-source-map-test.js:6:125)",
+  "(alpha @ ../alpha.ts:4:17) <- (t @ file:///Users/jlfwong/code/speedscope/sample/programs/javascript/sourcemaps/dist/parcel/typescript-source-map-test.js:8:140)",
+]
+`;
+
+exports[`source-map remapping of chrome-85-webpack 1`] = `
+Array [
+  "((anonymous) @ webpack://speedscope-sourcemap-test-project/alpha.ts:5:4) <- ((anonymous) @ file:///Users/jlfwong/code/speedscope/sample/programs/javascript/sourcemaps/dist/webpack/typescript-source-map-test.js:1:181)",
+  "(get @ webpack://speedscope-sourcemap-test-project/kludge.ts:13:3) <- (get @ file:///Users/jlfwong/code/speedscope/sample/programs/javascript/sourcemaps/dist/webpack/typescript-source-map-test.js:1:368)",
+  "(n.zap @ webpack://speedscope-sourcemap-test-project/kludge.ts:9:3) <- (n.zap @ file:///Users/jlfwong/code/speedscope/sample/programs/javascript/sourcemaps/dist/webpack/typescript-source-map-test.js:1:305)",
+  "(n constructor @ webpack://speedscope-sourcemap-test-project/kludge.ts:4:3) <- (n @ file:///Users/jlfwong/code/speedscope/sample/programs/javascript/sourcemaps/dist/webpack/typescript-source-map-test.js:1:243)",
+  "(n @ webpack://speedscope-sourcemap-test-project/gamma.ts:1:22) <- (n @ file:///Users/jlfwong/code/speedscope/sample/programs/javascript/sourcemaps/dist/webpack/typescript-source-map-test.js:1:34)",
+  "(beta @ webpack://speedscope-sourcemap-test-project/beta.ts:3:17) <- (o @ file:///Users/jlfwong/code/speedscope/sample/programs/javascript/sourcemaps/dist/webpack/typescript-source-map-test.js:1:88)",
+  "(r @ webpack://speedscope-sourcemap-test-project/delta.ts:3:22) <- (r @ file:///Users/jlfwong/code/speedscope/sample/programs/javascript/sourcemaps/dist/webpack/typescript-source-map-test.js:1:130)",
+  "(alpha @ webpack://speedscope-sourcemap-test-project/alpha.ts:4:17) <- (t @ file:///Users/jlfwong/code/speedscope/sample/programs/javascript/sourcemaps/dist/webpack/typescript-source-map-test.js:1:169)",
+]
+`;
+
+exports[`source-map remapping of firefox-79-webpack 1`] = `
+Array [
+  "(get @ webpack://speedscope-sourcemap-test-project/kludge.ts:13:3) <- (get @ file:///Users/jlfwong/code/speedscope/sample/programs/javascript/sourcemaps/dist/webpack/typescript-source-map-test.js:1:368)",
+  "(n constructor @ webpack://speedscope-sourcemap-test-project/kludge.ts:4:3) <- (n @ file:///Users/jlfwong/code/speedscope/sample/programs/javascript/sourcemaps/dist/webpack/typescript-source-map-test.js:1:243)",
+  "(n @ webpack://speedscope-sourcemap-test-project/gamma.ts:1:22) <- (n @ file:///Users/jlfwong/code/speedscope/sample/programs/javascript/sourcemaps/dist/webpack/typescript-source-map-test.js:1:34)",
+  "(n.prototype.zap @ webpack://speedscope-sourcemap-test-project/kludge.ts:9:3) <- (n.prototype.zap @ file:///Users/jlfwong/code/speedscope/sample/programs/javascript/sourcemaps/dist/webpack/typescript-source-map-test.js:1:305)",
+  "(beta @ webpack://speedscope-sourcemap-test-project/beta.ts:3:17) <- (o @ file:///Users/jlfwong/code/speedscope/sample/programs/javascript/sourcemaps/dist/webpack/typescript-source-map-test.js:1:88)",
+  "(r @ webpack://speedscope-sourcemap-test-project/delta.ts:3:22) <- (r @ file:///Users/jlfwong/code/speedscope/sample/programs/javascript/sourcemaps/dist/webpack/typescript-source-map-test.js:1:130)",
+  "(alpha @ webpack://speedscope-sourcemap-test-project/alpha.ts:4:17) <- (t @ file:///Users/jlfwong/code/speedscope/sample/programs/javascript/sourcemaps/dist/webpack/typescript-source-map-test.js:1:169)",
+  "(t/< @ webpack://speedscope-sourcemap-test-project/alpha.ts:5:4) <- (t/< @ file:///Users/jlfwong/code/speedscope/sample/programs/javascript/sourcemaps/dist/webpack/typescript-source-map-test.js:1:181)",
+]
+`;
+
+exports[`source-map remapping of safari-13-webpack 1`] = `
+Array [
+  "((anonymous) @ webpack://speedscope-sourcemap-test-project/alpha.ts:5:4) <- ((anonymous) @ file:///Users/jlfwong/code/speedscope/sample/programs/javascript/sourcemaps/dist/webpack/typescript-source-map-test.js:1:181)",
+  "(zap @ webpack://speedscope-sourcemap-test-project/kludge.ts:9:3) <- ((anonymous) @ file:///Users/jlfwong/code/speedscope/sample/programs/javascript/sourcemaps/dist/webpack/typescript-source-map-test.js:1:305)",
+  "(get @ webpack://speedscope-sourcemap-test-project/kludge.ts:13:3) <- (get @ file:///Users/jlfwong/code/speedscope/sample/programs/javascript/sourcemaps/dist/webpack/typescript-source-map-test.js:1:368)",
+  "(n constructor @ webpack://speedscope-sourcemap-test-project/kludge.ts:4:3) <- (n @ file:///Users/jlfwong/code/speedscope/sample/programs/javascript/sourcemaps/dist/webpack/typescript-source-map-test.js:1:243)",
+  "(n @ webpack://speedscope-sourcemap-test-project/gamma.ts:1:22) <- (n @ file:///Users/jlfwong/code/speedscope/sample/programs/javascript/sourcemaps/dist/webpack/typescript-source-map-test.js:1:34)",
+  "(beta @ webpack://speedscope-sourcemap-test-project/beta.ts:3:17) <- (o @ file:///Users/jlfwong/code/speedscope/sample/programs/javascript/sourcemaps/dist/webpack/typescript-source-map-test.js:1:88)",
+  "(r @ webpack://speedscope-sourcemap-test-project/delta.ts:3:22) <- (r @ file:///Users/jlfwong/code/speedscope/sample/programs/javascript/sourcemaps/dist/webpack/typescript-source-map-test.js:1:130)",
+  "(alpha @ webpack://speedscope-sourcemap-test-project/alpha.ts:4:17) <- (t @ file:///Users/jlfwong/code/speedscope/sample/programs/javascript/sourcemaps/dist/webpack/typescript-source-map-test.js:1:169)",
+]
+`;
--- a/Show More
+++ b/Show More
				`@@ -0,0 +1 @@`
				{"head":{"functionName":"(root)","url":"","lineNumber":-1,"bailoutReason":"","id":1,"scriptId":0,"hitCount":0,"children":[{"functionName":"","url":"","lineNumber":0,"callUID":1,"bailoutReason":"","id":2,"scriptId":0,"hitCount":0,"children":[{"functionName":"a","url":"","lineNumber":0,"callUID":2,"bailoutReason":"","id":3,"scriptId":0,"hitCount":0,"children":[{"functionName":"b","url":"","lineNumber":5,"callUID":3,"bailoutReason":"","id":4,"scriptId":0,"hitCount":0,"children":[{"functionName":"d","url":"","lineNumber":13,"callUID":4,"bailoutReason":"","id":5,"scriptId":0,"hitCount":14,"children":[]}]},{"functionName":"c","url":"","lineNumber":9,"callUID":3,"bailoutReason":"","id":6,"scriptId":0,"hitCount":0,"children":[{"functionName":"d","url":"","lineNumber":13,"callUID":6,"bailoutReason":"","id":7,"scriptId":0,"hitCount":14,"children":[]}]}]}]}]},"startTime":163140,"endTime":163140,"samples":[2,5,5,5,5,5,5,5,5,5,5,5,5,5,5,7,7,7,7,7,7,7,7,7,7,7,7,7,7],"timestamps":[163140599286,163140610861,163140611921,163140612966,163140614236,163140615507,163140616694,163140617968,163140619238,163140620258,163140621507,163140622765,163140624037,163140625303,163140626378,163140627649,163140628923,163140630191,163140631457,163140632746,163140634032,163140635304,163140636440,163140637716,163140638990,163140640255,163140641520,163140642791,163140644063,163140645206]}
				`@@ -0,0 +1 @@`
				{"version":3,"sources":["gamma.ts","beta.ts","delta.ts","alpha.ts","kludge.ts","typescript-source-map-test.ts"],"names":[],"mappings":";AAAO,aAAA,OAAA,eAAA,QAAA,aAAA,CAAA,OAAA,IAAA,QAAA,WAAA,EAAA,IAAM,EAAQ,WAEd,IADD,IAAA,EAAO,EACF,EAAI,EAAG,EAAI,IAAM,IACxB,GAAQ,EAEH,OAAA,GALF,QAAA,MAAA;;ACMN,aAAA,OAAA,eAAA,QAAA,aAAA,CAAA,OAAA,IAAA,QAAA,KAAA,EAND,IAAA,EAAA,QAAA,WAEM,SAAU,IACT,IAAA,IAAI,EAAI,EAAG,EAAI,GAAI,KACtB,EAAA,EAAA;;ACFG,aAAA,OAAA,eAAA,QAAA,aAAA,CAAA,OAAA,IAAA,QAAA,WAAA,EAFP,IAAA,EAAA,QAAA,WAEa,EAAQ,WACd,IAAA,IAAI,EAAI,EAAG,EAAI,GAAI,KACtB,EAAA,EAAA,UAFG,QAAA,MAAA;;ACQN,aAAA,OAAA,eAAA,QAAA,aAAA,CAAA,OAAA,IAAA,QAAA,MAAA,EAVD,IAAA,EAAA,QAAA,UACA,EAAA,QAAA,WAEM,SAAU,KACZ,WACK,IAAA,IAAI,EAAI,EAAG,EAAI,IAAM,KACxB,EAAA,EAAA,SACA,EAAA,EAAA,SAHF;;ACFJ,aAAA,OAAA,eAAA,QAAA,aAAA,CAAA,OAAA,IAAA,QAAA,YAAA,EAFA,IAAA,EAAA,QAAA,WAEA,EAAA,WACE,SAAA,KACE,EAAA,EAAA,SACA,QAAQ,IAAI,KAAK,OAWrB,OARE,EAAA,UAAA,IAAA,YACE,EAAA,EAAA,UAGF,OAAA,eAAI,EAAA,UAAA,QAAK,CAAT,IAAA,WAES,OADP,EAAA,EAAA,SACO,GAFA,YAAA,EAVX,cAAA,IAcA,EAdA,GAAA,QAAA,OAAA;;ACCA,aAHA,IAAA,EAAA,QAAA,YAEM,EAAI,IAAI,EAAJ,OACV,EAAE","file":"typescript-source-map-test.js","sourceRoot":"..","sourcesContent":["export const gamma = () => {\n let prod = 1\n for (let i = 1; i < 1000; i++) {\n prod *= i\n }\n return prod\n}\n","import {gamma} from './gamma'\n\nexport function beta() {\n for (let i = 0; i < 10; i++) {\n gamma()\n }\n}\n","import {gamma} from './gamma'\n\nexport const delta = function () {\n for (let i = 0; i < 10; i++) {\n gamma()\n }\n}\n","import {beta} from './beta'\nimport {delta} from './delta'\n\nexport function alpha() {\n ;(function () {\n for (let i = 0; i < 1000; i++) {\n beta()\n delta()\n }\n })()\n}\n","import {alpha} from './alpha'\n\nexport class Kludge {\n constructor() {\n alpha()\n console.log(this.floop)\n }\n\n zap() {\n alpha()\n }\n\n get floop(): number {\n alpha()\n return 1\n }\n}\n","import {Kludge} from './kludge'\n\nconst k = new Kludge()\nk.zap()\n"]}
				`@@ -0,0 +1 @@`
				{"version":3,"sources":["webpack://speedscope-sourcemap-test-project/./gamma.ts","webpack://speedscope-sourcemap-test-project/./beta.ts","webpack://speedscope-sourcemap-test-project/./delta.ts","webpack://speedscope-sourcemap-test-project/./alpha.ts","webpack://speedscope-sourcemap-test-project/./typescript-source-map-test.ts","webpack://speedscope-sourcemap-test-project/./kludge.ts"],"names":["gamma","prod","i","beta","delta","alpha","console","log","this","floop","zap"],"mappings":"mBAAO,IAAMA,EAAQ,WAEnB,IADA,IAAIC,EAAO,EACFC,EAAI,EAAGA,EAAI,IAAMA,IACxBD,GAAQC,EAEV,OAAOD,GCHF,SAASE,IACd,IAAK,IAAID,EAAI,EAAGA,EAAI,GAAIA,IACtBF,ICFG,IAAMI,EAAQ,WACnB,IAAK,IAAIF,EAAI,EAAGA,EAAI,GAAIA,IACtBF,KCDG,SAASK,KACb,WACC,IAAK,IAAIH,EAAI,EAAGA,EAAI,IAAMA,IACxBC,IACAC,IAHH,ICFO,ICAV,WACE,aACEC,IACAC,QAAQC,IAAIC,KAAKC,OAWrB,OARE,YAAAC,IAAA,WACEL,KAGF,sBAAI,oBAAK,C,IAAT,WAEE,OADAA,IACO,G,gCAEX,EAdA,KDCEK,O","file":"typescript-source-map-test.js","sourcesContent":["export const gamma = () => {\n let prod = 1\n for (let i = 1; i < 1000; i++) {\n prod *= i\n }\n return prod\n}\n","import {gamma} from './gamma'\n\nexport function beta() {\n for (let i = 0; i < 10; i++) {\n gamma()\n }\n}\n","import {gamma} from './gamma'\n\nexport const delta = function () {\n for (let i = 0; i < 10; i++) {\n gamma()\n }\n}\n","import {beta} from './beta'\nimport {delta} from './delta'\n\nexport function alpha() {\n ;(function () {\n for (let i = 0; i < 1000; i++) {\n beta()\n delta()\n }\n })()\n}\n","import {Kludge} from './kludge'\n\nconst k = new Kludge()\nk.zap()\n","import {alpha} from './alpha'\n\nexport class Kludge {\n constructor() {\n alpha()\n console.log(this.floop)\n }\n\n zap() {\n alpha()\n }\n\n get floop(): number {\n alpha()\n return 1\n }\n}\n"],"sourceRoot":""}