Bug 1593318 - De-duplicate head.js files in profiler tests; r=canaltinova

The tests for xpcshell and mochitests were pretty similar, and need to
do similar things. This commit creates a shread-head.js file where those
functions can be shared. This patch also renames a few shared functions
to give them more clarity in their current usage.

Differential Revision: https://phabricator.services.mozilla.com/D51933

--HG--
rename : tools/profiler/tests/xpcshell/head_profiler.js => tools/profiler/tests/xpcshell/head.js
extra : moz-landing-system : lando

tools/profiler/tests/browser/browser.ini

@@ -1,5 +1,6 @@
 [DEFAULT]
 support-files =
+  ../shared-head.js
   head.js
   do_work_500ms.html
   fixed_height.html

tools/profiler/tests/browser/head.js

@@ -1,27 +1,16 @@
+/* import-globals-from ../shared-head.js */
+
+Services.scriptloader.loadSubScript(
+  "chrome://mochitests/content/browser/tools/profiler/tests/browser/shared-head.js",
+  this
+);
+
 const { BrowserTestUtils } = ChromeUtils.import(
   "resource://testing-common/BrowserTestUtils.jsm"
 );
 
 const BASE_URL = "http://example.com/browser/tools/profiler/tests/browser/";
 
-const defaultSettings = {
-  entries: 1000000, // 9MB
-  interval: 1, // ms
-  features: ["threads"],
-  threads: ["GeckoMain"],
-};
-
-function startProfiler(callersSettings) {
-  const settings = Object.assign({}, defaultSettings, callersSettings);
-  Services.profiler.StartProfiler(
-    settings.entries,
-    settings.interval,
-    settings.features,
-    settings.threads,
-    settings.duration
-  );
-}
-
 /**
  * This is a helper function that will stop the profiler of the browser running
  * with PID contentPid.
@@ -70,37 +59,3 @@ async function stopProfilerAndGetThreads(contentPid) {
 
   return stopProfilerNowAndGetThreads(contentPid);
 }
-
-/**
- * This is a helper function be able to run `await wait(500)`. Unfortunately this
- * is needed as the act of collecting functions relies on the periodic sampling of
- * the threads. See: https://bugzilla.mozilla.org/show_bug.cgi?id=1529053
- *
- * @param {number} time
- * @returns {Promise}
- */
-function wait(time) {
-  return new Promise(resolve => {
-    // eslint-disable-next-line mozilla/no-arbitrary-setTimeout
-    setTimeout(resolve, time);
-  });
-}
-
-/**
- * Get the payloads of a type from a single thread.
- *
- * @param {Object} thread The thread from a profile.
- * @param {string} type The marker payload type, e.g. "DiskIO".
- * @return {Array} The payloads.
- */
-function getPayloadsOfType(thread, type) {
-  const { markers } = thread;
-  const results = [];
-  for (const markerTuple of markers.data) {
-    const payload = markerTuple[markers.schema.data];
-    if (payload && payload.type === type) {
-      results.push(payload);
-    }
-  }
-  return results;
-}

tools/profiler/tests/shared-head.js

@@ -0,0 +1,110 @@
+/* This Source Code Form is subject to the terms of the Mozilla Public
+ * License, v. 2.0. If a copy of the MPL was not distributed with this
+ * file, You can obtain one at http://mozilla.org/MPL/2.0/. */
+
+/**
+ * This file contains utilities that can be shared between xpcshell tests and mochitests.
+ */
+
+// This Services declaration may shadow another from head.js, so define it as
+// a var rather than a const.
+var { Services } = ChromeUtils.import("resource://gre/modules/Services.jsm");
+
+const defaultSettings = {
+  entries: 1000000, // 9MB
+  interval: 1, // ms
+  features: ["threads"],
+  threads: ["GeckoMain"],
+};
+
+function startProfiler(callersSettings) {
+  const settings = Object.assign({}, defaultSettings, callersSettings);
+  Services.profiler.StartProfiler(
+    settings.entries,
+    settings.interval,
+    settings.features,
+    settings.threads,
+    settings.duration
+  );
+}
+
+/**
+ * This is a helper function be able to run `await wait(500)`. Unfortunately
+ * this is needed as the act of collecting functions relies on the periodic
+ * sampling of the threads. See:
+ * https://bugzilla.mozilla.org/show_bug.cgi?id=1529053
+ *
+ * @param {number} time
+ * @returns {Promise}
+ */
+function wait(time) {
+  return new Promise(resolve => {
+    // eslint-disable-next-line mozilla/no-arbitrary-setTimeout
+    setTimeout(resolve, time);
+  });
+}
+
+/**
+ * Get the payloads of a type recursively, including from all subprocesses.
+ *
+ * @param {Object} profile The gecko profile.
+ * @param {string} type The marker payload type, e.g. "DiskIO".
+ * @param {Array} payloadTarget The recursive list of payloads.
+ * @return {Array} The final payloads.
+ */
+function getPayloadsOfTypeFromAllThreads(profile, type, payloadTarget = []) {
+  for (const { markers } of profile.threads) {
+    for (const markerTuple of markers.data) {
+      const payload = markerTuple[markers.schema.data];
+      if (payload && payload.type === type) {
+        payloadTarget.push(payload);
+      }
+    }
+  }
+
+  for (const subProcess of profile.processes) {
+    getPayloadsOfTypeFromAllThreads(subProcess, type, payloadTarget);
+  }
+
+  return payloadTarget;
+}
+
+/**
+ * Get the payloads of a type from a single thread.
+ *
+ * @param {Object} thread The thread from a profile.
+ * @param {string} type The marker payload type, e.g. "DiskIO".
+ * @return {Array} The payloads.
+ */
+function getPayloadsOfType(thread, type) {
+  const { markers } = thread;
+  const results = [];
+  for (const markerTuple of markers.data) {
+    const payload = markerTuple[markers.schema.data];
+    if (payload && payload.type === type) {
+      results.push(payload);
+    }
+  }
+  return results;
+}
+
+/**
+ * It can be helpful to force the profiler to collect a JavaScript sample. This
+ * function spins on a while loop until at least one more sample is collected.
+ *
+ * @return {number} The index of the collected sample.
+ */
+function captureAtLeastOneJsSample() {
+  function getProfileSampleCount() {
+    const profile = Services.profiler.getProfileData();
+    return profile.threads[0].samples.data.length;
+  }
+
+  const sampleCount = getProfileSampleCount();
+  // Create an infinite loop until a sample has been collected.
+  while (true) {
+    if (sampleCount < getProfileSampleCount()) {
+      return sampleCount;
+    }
+  }
+}

tools/profiler/tests/xpcshell/head.js

@@ -2,52 +2,26 @@
  * License, v. 2.0. If a copy of the MPL was not distributed with this
  * file, You can obtain one at http://mozilla.org/MPL/2.0/. */
 
+/* import-globals-from ../shared-head.js */
+
+// This Services declaration may shadow another from head.js, so define it as
+// a var rather than a const.
 var { Services } = ChromeUtils.import("resource://gre/modules/Services.jsm");
-var { AppConstants } = ChromeUtils.import(
+
+const { AppConstants } = ChromeUtils.import(
   "resource://gre/modules/AppConstants.jsm"
 );
-var { setTimeout } = ChromeUtils.import("resource://gre/modules/Timer.jsm");
+const { setTimeout } = ChromeUtils.import("resource://gre/modules/Timer.jsm");
 
-/**
- * Get the payloads of a type recursively, including from all subprocesses.
- *
- * @param {Object} profile The gecko profile.
- * @param {string} type The marker payload type, e.g. "DiskIO".
- * @param {Array} payloadTarget The recursive list of payloads.
- * @return {Array} The final payloads.
- */
-function getAllPayloadsOfType(profile, type, payloadTarget = []) {
-  for (const { markers } of profile.threads) {
-    for (const markerTuple of markers.data) {
-      const payload = markerTuple[markers.schema.data];
-      if (payload && payload.type === type) {
-        payloadTarget.push(payload);
-      }
-    }
-  }
-
-  for (const subProcess of profile.processes) {
-    getAllPayloadsOfType(subProcess, type, payloadTarget);
-  }
-
-  return payloadTarget;
-}
-
-/**
- * This is a helper function be able to run `await wait(500)`. Unfortunately
- * this is needed as the act of collecting functions relies on the periodic
- * sampling of the threads. See:
- * https://bugzilla.mozilla.org/show_bug.cgi?id=1529053
- *
- * @param {number} time
- * @returns {Promise}
- */
-function wait(time) {
-  return new Promise(resolve => {
-    // eslint-disable-next-line mozilla/no-arbitrary-setTimeout
-    setTimeout(resolve, time);
-  });
+// Load the shared head
+const sharedHead = do_get_file("shared-head.js", false);
+if (!sharedHead) {
+  throw new Error("Could not load the shared head.");
 }
+Services.scriptloader.loadSubScript(
+  Services.io.newFileURI(sharedHead).spec,
+  this
+);
 
 /**
  * This function takes a thread, and a sample tuple from the "data" array, and
@@ -81,28 +55,6 @@ function getInflatedStackLocations(thread, sample) {
   return locations.reverse();
 }
 
-/**
- * It can be helpful to deterministically do at least one more profile sample.
- * Sampling is done based on a timer. This function spins on a while loop until
- * at least one more sample is collected.
- *
- * @return {number} The index of the collected sample.
- */
-function doAtLeastOnePeriodicSample() {
-  function getProfileSampleCount() {
-    const profile = Services.profiler.getProfileData();
-    return profile.threads[0].samples.data.length;
-  }
-
-  const sampleCount = getProfileSampleCount();
-  // Create an infinite loop until a sample has been collected.
-  while (true) {
-    if (sampleCount < getProfileSampleCount()) {
-      return sampleCount;
-    }
-  }
-}
-
 /**
  * This utility matches up stacks to see if they contain a certain sequence of
  * stack frames. A correctly functioning profiler will have a certain sequence

tools/profiler/tests/xpcshell/test_feature_js.js

@@ -17,7 +17,7 @@ add_task(async () => {
   Services.profiler.StartProfiler(entries, interval, features, threads);
 
   // Call the following to get a nice stack in the profiler:
-  // functionA -> functionB -> functionC -> doAtLeastOnePeriodicSample
+  // functionA -> functionB -> functionC -> captureAtLeastOneJsSample
   const sampleIndex = await functionA();
 
   const profile = await Services.profiler.getProfileDataAsync();
@@ -59,5 +59,5 @@ function functionB() {
 }
 
 async function functionC() {
-  return doAtLeastOnePeriodicSample();
+  return captureAtLeastOneJsSample();
 }

tools/profiler/tests/xpcshell/test_feature_mainthreadio.js

@@ -113,7 +113,7 @@ async function startProfilerAndgetFileIOPayloads(features, filename) {
 
   const profile = await Services.profiler.getProfileDataAsync();
   Services.profiler.StopProfiler();
-  return getAllPayloadsOfType(profile, "FileIO");
+  return getPayloadsOfTypeFromAllThreads(profile, "FileIO");
 }
 
 /**

tools/profiler/tests/xpcshell/test_feature_stackwalking.js

@@ -18,7 +18,7 @@ add_task(async () => {
   const features = ["stackwalk"];
 
   Services.profiler.StartProfiler(entries, interval, features, threads);
-  const sampleIndex = await doAtLeastOnePeriodicSample();
+  const sampleIndex = await captureAtLeastOneJsSample();
 
   const profile = await Services.profiler.getProfileDataAsync();
   const [thread] = profile.threads;

tools/profiler/tests/xpcshell/test_merged_stacks.js

@@ -17,7 +17,7 @@ add_task(async () => {
   Services.profiler.StartProfiler(entries, interval, features, threads);
 
   // Call the following to get a nice stack in the profiler:
-  // functionA -> functionB -> functionC -> doAtLeastOnePeriodicSample
+  // functionA -> functionB -> functionC
   const sampleIndex = await functionA();
 
   const profile = await Services.profiler.getProfileDataAsync();
@@ -71,5 +71,5 @@ function functionB() {
 }
 
 async function functionC() {
-  return doAtLeastOnePeriodicSample();
+  return captureAtLeastOneJsSample();
 }

tools/profiler/tests/xpcshell/test_responsiveness.js

@@ -49,5 +49,5 @@ function doSyncWork(milliseconds) {
 
 function functionA() {
   doSyncWork(100);
-  doAtLeastOnePeriodicSample();
+  captureAtLeastOneJsSample();
 }

tools/profiler/tests/xpcshell/xpcshell.ini

@@ -1,5 +1,7 @@
 [DEFAULT]
-head = head_profiler.js
+head = head.js
+support-files =
+  ../shared-head.js
 skip-if = toolkit == 'android'
 
 [test_active_configuration.js]