fix: extend tracing startRecording API to take a full tracing config (#13914)

This allows memory-infra to be traced correctly.
Fixes #12506.

spec/api-content-tracing-spec.js

@@ -0,0 +1,145 @@
+const { remote } = require('electron')
+const chai = require('chai')
+const dirtyChai = require('dirty-chai')
+const fs = require('fs')
+const path = require('path')
+
+const { expect } = chai
+const { app, contentTracing } = remote
+
+chai.use(dirtyChai)
+
+const timeout = async (milliseconds) => {
+  return new Promise((resolve) => {
+    setTimeout(resolve, milliseconds)
+  })
+}
+
+const getPathInATempFolder = (filename) => {
+  return path.join(app.getPath('temp'), filename)
+}
+
+describe('contentTracing', () => {
+  beforeEach(function () {
+    // FIXME: The tests are skipped on arm/arm64.
+    if (process.platform === 'linux' &&
+        ['arm', 'arm64'].includes(process.arch)) {
+      this.skip()
+    }
+  })
+
+  const startRecording = async (options) => {
+    return new Promise((resolve) => {
+      contentTracing.startRecording(options, () => {
+        resolve()
+      })
+    })
+  }
+
+  const stopRecording = async (filePath) => {
+    return new Promise((resolve) => {
+      contentTracing.stopRecording(filePath, (resultFilePath) => {
+        resolve(resultFilePath)
+      })
+    })
+  }
+
+  const record = async (options, outputFilePath, recordTimeInMilliseconds = 1e3) => {
+    await app.whenReady()
+
+    await startRecording(options)
+    await timeout(recordTimeInMilliseconds)
+    const resultFilePath = await stopRecording(outputFilePath)
+
+    return resultFilePath
+  }
+
+  const outputFilePath = getPathInATempFolder('trace.json')
+  beforeEach(() => {
+    if (fs.existsSync(outputFilePath)) {
+      fs.unlinkSync(outputFilePath)
+    }
+  })
+
+  describe('startRecording', function () {
+    this.timeout(5e3)
+
+    const getFileSizeInKiloBytes = (filePath) => {
+      const stats = fs.statSync(filePath)
+      const fileSizeInBytes = stats.size
+      const fileSizeInKiloBytes = fileSizeInBytes / 1024
+      return fileSizeInKiloBytes
+    }
+
+    it('accepts an empty config', async () => {
+      const config = {}
+      await record(config, outputFilePath)
+
+      expect(fs.existsSync(outputFilePath)).to.be.true()
+
+      const fileSizeInKiloBytes = getFileSizeInKiloBytes(outputFilePath)
+      expect(fileSizeInKiloBytes).to.be.above(0,
+        `the trace output file is empty, check "${outputFilePath}"`)
+    })
+
+    it('accepts a trace config', async () => {
+      // (alexeykuzmin): All categories are excluded on purpose,
+      // so only metadata gets into the output file.
+      const config = {
+        excluded_categories: ['*']
+      }
+      await record(config, outputFilePath)
+
+      expect(fs.existsSync(outputFilePath)).to.be.true()
+
+      // If the `excluded_categories` param above is not respected
+      // the file size will be above 50KB.
+      const fileSizeInKiloBytes = getFileSizeInKiloBytes(outputFilePath)
+      const expectedMaximumFileSize = 10 // Depends on a platform.
+
+      expect(fileSizeInKiloBytes).to.be.above(0,
+        `the trace output file is empty, check "${outputFilePath}"`)
+      expect(fileSizeInKiloBytes).to.be.below(expectedMaximumFileSize,
+        `the trace output file is suspiciously large (${fileSizeInKiloBytes}KB),
+        check "${outputFilePath}"`)
+    })
+
+    it('accepts "categoryFilter" and "traceOptions" as a config', async () => {
+      // (alexeykuzmin): All categories are excluded on purpose,
+      // so only metadata gets into the output file.
+      const config = {
+        categoryFilter: '__ThisIsANonexistentCategory__',
+        traceOptions: ''
+      }
+      await record(config, outputFilePath)
+
+      expect(fs.existsSync(outputFilePath)).to.be.true()
+
+      // If the `categoryFilter` param above is not respected
+      // the file size will be above 50KB.
+      const fileSizeInKiloBytes = getFileSizeInKiloBytes(outputFilePath)
+      const expectedMaximumFileSize = 10 // Depends on a platform.
+
+      expect(fileSizeInKiloBytes).to.be.above(0,
+        `the trace output file is empty, check "${outputFilePath}"`)
+      expect(fileSizeInKiloBytes).to.be.below(expectedMaximumFileSize,
+        `the trace output file is suspiciously large (${fileSizeInKiloBytes}KB),
+        check "${outputFilePath}"`)
+    })
+  })
+
+  describe('stopRecording', function () {
+    this.timeout(5e3)
+
+    it('calls its callback with a result file path', async () => {
+      const resultFilePath = await record(/* options */ {}, outputFilePath)
+      expect(resultFilePath).to.be.a('string').and.be.equal(outputFilePath)
+    })
+
+    // FIXME(alexeykuzmin): https://github.com/electron/electron/issues/16019
+    xit('creates a temporary file when an empty string is passed', async function () {
+      const resultFilePath = await record(/* options */ {}, /* outputFilePath */ '')
+      expect(resultFilePath).to.be.a('string').that.is.not.empty()
+    })
+  })
+})