Adding upstream version 86.0.1.upstream/86.0.1upstream

Signed-off-by: Daniel Baumann <daniel.baumann@progress-linux.org>

4 files changed, 348 insertions, 0 deletions

diff --git a/devtools/shared/test-helpers/.eslintrc.js b/devtools/shared/test-helpers/.eslintrc.js
new file mode 100644
index 0000000000..47885ab596
--- /dev/null
+++ b/devtools/shared/test-helpers/.eslintrc.js
@@ -0,0 +1,10 @@
+/* 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/. */
+
+"use strict";
+
+module.exports = {
+  // Extend from the shared list of defined globals for mochitests.
+  extends: "../../.eslintrc.mochitests.js",
+};
diff --git a/devtools/shared/test-helpers/allocation-tracker.js b/devtools/shared/test-helpers/allocation-tracker.js
new file mode 100644
index 0000000000..510fdbd29b
--- /dev/null
+++ b/devtools/shared/test-helpers/allocation-tracker.js
@@ -0,0 +1,249 @@
+/* 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 helps tracking Javascript object allocations.
+ * It is only included in local builds as a debugging helper.
+ *
+ * It is typicaly used when running DevTools tests (either mochitests or DAMP).
+ * To use it, you need to set the following environment variable:
+ *   DEBUG_DEVTOOLS_ALLOCATIONS="normal"
+ *     This will only print the number of JS objects created during your test.
+ *   DEBUG_DEVTOOLS_ALLOCATIONS="verbose"
+ *     This will print the allocation sites of all the JS objects created during your
+ *     test. i.e. from which files and lines the objects have been created.
+ * In both cases, look for "DEVTOOLS ALLOCATION" in your terminal to see tracker's
+ * output.
+ *
+ * But you can also import it from your test script if you want to focus on one
+ * particular piece of code:
+ *   const { allocationTracker } =
+ *     require("devtools/shared/test-helpers/allocation-tracker");
+ *   // Calling `allocationTracker` will immediately start recording allocations
+ *   let tracker = allocationTracker();
+ *
+ *   // Do something
+ *
+ *   // If you want to log all the allocation sites, call this method:
+ *   tracker.logAllocationSites();
+ *   // Or, if you want to only print the number of objects being allocated, call this:
+ *   tracker.logCount();
+ *   // Once you are done, stop the tracker as it slow down execution a lot.
+ *   tracker.stop();
+ */
+
+"use strict";
+
+const { Cu } = require("chrome");
+const ChromeUtils = require("ChromeUtils");
+
+const global = Cu.getGlobalForObject(this);
+const { addDebuggerToGlobal } = ChromeUtils.import(
+  "resource://gre/modules/jsdebugger.jsm"
+);
+addDebuggerToGlobal(global);
+
+/**
+ * Start recording JS object allocations.
+ *
+ * @param Object watchGlobal
+ *        One global object to observe. Only allocation made from this global
+ *        will be recorded.
+ * @param Boolean watchAllGlobals
+ *        If true, allocations from everywhere are going to be recorded.
+ * @param Boolean watchAllGlobals
+ *        If true, only allocations made from DevTools contexts are going to be recorded.
+ */
+exports.allocationTracker = function({
+  watchGlobal,
+  watchAllGlobals,
+  watchDevToolsGlobals,
+} = {}) {
+  dump("DEVTOOLS ALLOCATION: Start logging allocations\n");
+  let dbg = new global.Debugger();
+
+  // Enable allocation site tracking, to have the stack for each allocation
+  dbg.memory.trackingAllocationSites = true;
+  // Force saving *all* the allocation sites
+  dbg.memory.allocationSamplingProbability = 1.0;
+  // Bumps the default buffer size, which may prevent recording all the test allocations
+  dbg.memory.maxAllocationsLogLength = 5000000;
+
+  let acceptGlobal;
+  if (watchGlobal) {
+    acceptGlobal = () => false;
+    dbg.addDebuggee(watchGlobal);
+  } else if (watchAllGlobals) {
+    acceptGlobal = () => true;
+  } else if (watchDevToolsGlobals) {
+    // Only accept globals related to DevTools
+    acceptGlobal = g => {
+      // self-hosting-global crashes when trying to call unsafeDereference
+      if (g.class == "self-hosting-global") {
+        return false;
+      }
+      const ref = g.unsafeDereference();
+      const location = Cu.getRealmLocation(ref);
+      const accept = !!location.match(/devtools/i);
+      dump(
+        "TRACKER NEW GLOBAL: " + (accept ? "+" : "-") + " : " + location + "\n"
+      );
+      return accept;
+    };
+  }
+
+  // Watch all globals
+  if (watchAllGlobals || watchDevToolsGlobals) {
+    dbg.addAllGlobalsAsDebuggees();
+
+    for (const g of dbg.getDebuggees()) {
+      if (!acceptGlobal(g)) {
+        dbg.removeDebuggee(g);
+      }
+    }
+  }
+
+  // Remove this global to ignore all its object/JS
+  dbg.removeDebuggee(global);
+
+  // addAllGlobalsAsDebuggees won't automatically track new ones,
+  // so ensure tracking all new globals
+  dbg.onNewGlobalObject = function(g) {
+    if (acceptGlobal(g)) {
+      dbg.addDebuggee(g);
+    }
+  };
+
+  return {
+    get overflowed() {
+      return dbg.memory.allocationsLogOverflowed;
+    },
+
+    /**
+     * Print to stdout data about all recorded allocations
+     *
+     * It prints an array of allocations per file, sorted by files allocating the most
+     * objects. And get detail of allocation per line.
+     *
+     *   [{ src: "chrome://devtools/content/framework/toolbox.js",
+     *      count: 210, // Total # of allocs for toolbox.js
+     *      lines: [
+     *       "10: 200", // toolbox.js allocation 200 objects on line 10
+     *       "124: 10
+     *      ]
+     *    },
+     *    { src: "chrome://devtools/content/inspector/inspector.js",
+     *      count: 12,
+     *      lines: [
+     *       "20: 12",
+     *      ]
+     *    }]
+     *
+     * @param first Number
+     *        Retrieve only the top $first script allocation the most
+     *        objects
+     */
+    logAllocationSites({ first = 5 } = {}) {
+      // Fetch all allocation sites from Debugger API
+      const allocations = dbg.memory.drainAllocationsLog();
+
+      // Process Debugger API data to store allocations by file
+      // sources = {
+      //   "chrome://devtools/content/framework/toolbox.js": {
+      //     count: 10, // total # of allocs for toolbox.js
+      //     lines: {
+      //       10: 200, // total # of allocs for toolbox.js line 10
+      //       124: 10, // same, for line 124
+      //       ..
+      //     }
+      //   }
+      // }
+      const sources = {};
+      for (const alloc of allocations) {
+        const { frame } = alloc;
+        let src = "UNKNOWN";
+        let line = -1;
+        try {
+          if (frame) {
+            src = frame.source || "UNKNOWN";
+            line = frame.line || -1;
+          }
+        } catch (e) {
+          // For some frames accessing source throws
+        }
+
+        let item = sources[src];
+        if (!item) {
+          item = sources[src] = { count: 0, lines: {} };
+        }
+        item.count++;
+        if (line != -1) {
+          if (!item.lines[line]) {
+            item.lines[line] = 0;
+          }
+          item.lines[line]++;
+        }
+      }
+
+      const allocationList = Object.entries(sources)
+        // Sort by number of total object
+        .sort(([srcA, itemA], [srcB, itemB]) => itemA.count < itemB.count)
+        // Keep only the first 5 sources, with the most allocations
+        .filter((_, i) => i < first)
+        .map(([src, item]) => {
+          const lines = [];
+          Object.entries(item.lines)
+            .filter(([line, count]) => count > 5)
+            .sort(([lineA, countA], [lineB, countB]) => {
+              if (countA != countB) {
+                return countA < countB;
+              }
+              return lineA < lineB;
+            })
+            .forEach(([line, count]) => {
+              // Compress the data to make it readable on stdout
+              lines.push(line + ": " + count);
+            });
+          return { src, count: item.count, lines };
+        });
+      dump(
+        "DEVTOOLS ALLOCATION: Javascript object allocations: " +
+          allocations.length +
+          "\n" +
+          JSON.stringify(allocationList, null, 2) +
+          "\n"
+      );
+    },
+
+    logCount() {
+      dump(
+        "DEVTOOLS ALLOCATION: Javascript object allocations: " +
+          this.countAllocations() +
+          "\n"
+      );
+    },
+
+    countAllocations() {
+      // Fetch all allocation sites from Debugger API
+      const allocations = dbg.memory.drainAllocationsLog();
+      return allocations.length;
+    },
+
+    flushAllocations() {
+      dbg.memory.drainAllocationsLog();
+    },
+
+    stillAllocatedObjects() {
+      const sensus = dbg.memory.takeCensus({ breakdown: { by: "count" } });
+      return sensus.count;
+    },
+
+    stop() {
+      dump("DEVTOOLS ALLOCATION: Stop logging allocations\n");
+      dbg.onNewGlobalObject = undefined;
+      dbg.removeAllDebuggees();
+      dbg = null;
+    },
+  };
+};
diff --git a/devtools/shared/test-helpers/browser.ini b/devtools/shared/test-helpers/browser.ini
new file mode 100644
index 0000000000..c729f4d473
--- /dev/null
+++ b/devtools/shared/test-helpers/browser.ini
@@ -0,0 +1,7 @@
+[DEFAULT]
+tags = devtools
+subsuite = devtools
+support-files =
+  allocation-tracker.js
+
+[browser_allocation_tracker.js]
diff --git a/devtools/shared/test-helpers/browser_allocation_tracker.js b/devtools/shared/test-helpers/browser_allocation_tracker.js
new file mode 100644
index 0000000000..8fe26dac1b
--- /dev/null
+++ b/devtools/shared/test-helpers/browser_allocation_tracker.js
@@ -0,0 +1,82 @@
+/* Any copyright is dedicated to the Public Domain.
+ * http://creativecommons.org/publicdomain/zero/1.0/ */
+
+"use strict";
+
+// Load the tracker in a dedicated loader using invisibleToDebugger and freshCompartment
+// so that it can inspect any other module/compartment, even DevTools, chrome,
+// and this script!
+const { DevToolsLoader } = ChromeUtils.import(
+  "resource://devtools/shared/Loader.jsm"
+);
+const loader = new DevToolsLoader({
+  invisibleToDebugger: true,
+  freshCompartment: true,
+});
+const { allocationTracker } = loader.require(
+  "chrome://mochitests/content/browser/devtools/shared/test-helpers/allocation-tracker"
+);
+
+add_task(async function() {
+  // Use a sandbox to allocate test javascript object in order to avoid any
+  // external noise
+  const global = Cu.Sandbox("http://example.com");
+
+  const tracker = allocationTracker({ watchGlobal: global });
+  const before = tracker.stillAllocatedObjects();
+
+  /* eslint-disable no-undef */
+  Cu.evalInSandbox(
+    "let list; new " +
+      function() {
+        list = [];
+        for (let i = 0; i < 1000; i++) {
+          list.push({});
+        }
+      },
+    global,
+    undefined,
+    "test-file.js",
+    1,
+    /* enforceFilenameRestrictions */ false
+  );
+  /* eslint-enable no-undef */
+
+  const allocations = tracker.countAllocations();
+  ok(
+    allocations > 1000,
+    `At least 1000 objects are reported as created (${allocations})`
+  );
+
+  // Uncomment this and comment the call to `countAllocations` to debug the allocations.
+  // The call to `countAllocations` will reset the allocation record.
+  // tracker.logAllocationSites();
+
+  const afterCreation = tracker.stillAllocatedObjects();
+  ok(
+    afterCreation - before > 1000,
+    `At least 1000 more objects are reported still allocated (${before}` +
+      ` + ${afterCreation - before} -> ${afterCreation})`
+  );
+
+  Cu.evalInSandbox(
+    "list = null;",
+    global,
+    undefined,
+    "test-file.js",
+    7,
+    /* enforceFilenameRestrictions */ false
+  );
+
+  Cu.forceGC();
+  Cu.forceCC();
+
+  const afterGC = tracker.stillAllocatedObjects();
+  ok(
+    afterCreation - afterGC > 1000,
+    `At least 1000 less objects are reported still allocated (${afterCreation}` +
+      ` -(${afterGC - afterCreation})-> ${afterGC})`
+  );
+
+  tracker.stop();
+});