Fix crash when importing from stackprof without raw_timestamp_deltas (#207)

Fixes #200

src/import/index.test.ts

@@ -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)
 })

src/import/index.ts

@@ -137,7 +137,7 @@ async function _importProfileGroup(dataSource: ProfileDataSource): Promise<Profi
     } 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) {
+    } 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) {