Backed out 3 changesets (bug 1468761) for telemetry related xpcshell failures. CLOSED TREE

Backed out changeset 8c08dcec61d8 (bug 1468761)
Backed out changeset 9ee8406cf1d3 (bug 1468761)
Backed out changeset 65bfae07e0f4 (bug 1468761)

browser/base/content/test/tabs/browser_abandonment_telemetry.js

@@ -206,11 +206,11 @@ const PROBE_TESTS = [
  */
 function assertOnlyOneTypeSet(snapshot, category) {
   let categoryIndex = CATEGORIES.indexOf(category);
-  Assert.equal(snapshot.values[categoryIndex], 1,
+  Assert.equal(snapshot.counts[categoryIndex], 1,
                `Should have seen the ${category} count increment.`);
   // Use Array.prototype.reduce to sum up all of the
   // snapshot.count entries
-  Assert.equal(Object.values(snapshot.values).reduce((a, b) => a + b, 0), 1,
+  Assert.equal(snapshot.counts.reduce((a, b) => a + b), 1,
                "Should only be 1 collected value.");
 }
 

browser/base/content/test/tabs/browser_tabCloseProbes.js

@@ -16,7 +16,7 @@ var gNoAnimHistogram = Services.telemetry
 function snapshotCount(snapshot) {
   // Use Array.prototype.reduce to sum up all of the
   // snapshot.count entries
-  return Object.values(snapshot.values).reduce((a, b) => a + b, 0);
+  return snapshot.counts.reduce((a, b) => a + b);
 }
 
 /**

browser/base/content/test/tabs/browser_tabSpinnerProbe.js

@@ -50,7 +50,10 @@ function hangContentProcess(browser, aMs) {
 async function testProbe(aProbe) {
   info(`Testing probe: ${aProbe}`);
   let histogram = Services.telemetry.getHistogramById(aProbe);
-  let delayTime = MIN_HANG_TIME + 1; // Pick a bucket arbitrarily
+  let buckets = histogram.snapshot().ranges.filter(function(value) {
+    return (value > MIN_HANG_TIME && value < MAX_HANG_TIME);
+  });
+  let delayTime = buckets[0]; // Pick a bucket arbitrarily
 
   // The tab spinner does not show up instantly. We need to hang for a little
   // bit of extra time to account for the tab spinner delay.
@@ -75,7 +78,7 @@ async function testProbe(aProbe) {
   // Now we should have a hang in our histogram.
   let snapshot = histogram.snapshot();
   BrowserTestUtils.removeTab(hangTab);
-  ok(sum(Object.values(snapshot.values)) > 0,
+  ok(sum(snapshot.counts) > 0,
    `Spinner probe should now have a value in some bucket`);
 }
 

browser/base/content/test/trackingUI/browser_trackingUI_telemetry.js

@@ -22,7 +22,7 @@ function getShieldHistogram() {
 }
 
 function getShieldCounts() {
-  return getShieldHistogram().snapshot().values;
+  return getShieldHistogram().snapshot().counts;
 }
 
 add_task(async function setup() {
@@ -33,7 +33,7 @@ add_task(async function setup() {
   ok(!TrackingProtection.enabled, "TP is not enabled");
 
   let enabledCounts =
-    Services.telemetry.getHistogramById("TRACKING_PROTECTION_ENABLED").snapshot().values;
+    Services.telemetry.getHistogramById("TRACKING_PROTECTION_ENABLED").snapshot().counts;
   is(enabledCounts[0], 1, "TP was not enabled on start up");
 
   let scalars = Services.telemetry.snapshotScalars(

browser/components/extensions/test/browser/browser_ext_browserAction_telemetry.js

@@ -32,11 +32,11 @@ const CATEGORIES = [
  */
 function assertOnlyOneTypeSet(snapshot, category) {
   let categoryIndex = CATEGORIES.indexOf(category);
-  Assert.equal(snapshot.values[categoryIndex], 1,
+  Assert.equal(snapshot.counts[categoryIndex], 1,
                `Should have seen the ${category} count increment.`);
   // Use Array.prototype.reduce to sum up all of the
   // snapshot.count entries
-  Assert.equal(Object.values(snapshot.values).reduce((a, b) => a + b, 0), 1,
+  Assert.equal(snapshot.counts.reduce((a, b) => a + b), 1,
                "Should only be 1 collected value.");
 }
 

browser/components/extensions/test/browser/browser_ext_pageAction_telemetry.js

@@ -9,7 +9,7 @@ const EXTENSION_ID1 = "@test-extension1";
 const EXTENSION_ID2 = "@test-extension2";
 
 function snapshotCountsSum(snapshot) {
-  return Object.values(snapshot.values).reduce((a, b) => a + b, 0);
+  return snapshot.counts.reduce((a, b) => a + b, 0);
 }
 
 function histogramCountsSum(histogram) {

browser/components/search/test/browser_aboutSearchReset.js

@@ -20,13 +20,13 @@ const kStatusPref = "browser.search.reset.status";
 function checkTelemetryRecords(expectedValue) {
   let histogram = Services.telemetry.getHistogramById("SEARCH_RESET_RESULT");
   let snapshot = histogram.snapshot();
+  // The probe is declared with 5 values, but we get 6 back from .counts
+  let expectedCounts = [0, 0, 0, 0, 0, 0];
   if (expectedValue != null) {
-    Assert.deepEqual(snapshot.values[expectedValue], 1,
-                     "histogram has expected content");
-  } else {
-    Assert.deepEqual(!!snapshot.values[expectedValue], false,
-                     "histogram has expected content");
+    expectedCounts[expectedValue] = 1;
   }
+  Assert.deepEqual(snapshot.counts, expectedCounts,
+                   "histogram has expected content");
   histogram.clear();
 }
 

browser/components/sessionstore/test/browser_522375.js

@@ -7,7 +7,7 @@ function test() {
   var snapshot = Services.telemetry.getHistogramById("STARTUP_MEASUREMENT_ERRORS")
                                    .snapshot();
 
-  if (snapshot.values[0] == 0)
+  if (snapshot.counts[0] == 0)
     ok(startup_info.process <= startup_info.main, "process created before main is run " + uneval(startup_info));
   else
     todo(false, "An error occurred while recording the process creation timestamp, skipping this test");

browser/components/sessionstore/test/unit/test_histogram_corrupt_files.js

@@ -62,8 +62,8 @@ add_task(async function test_no_files_exist() {
   // Checking if the histogram is updated negatively
   let h = Telemetry.getHistogramById(HistogramId);
   let s = h.snapshot();
-  Assert.equal(s.values[0], 1, "One probe for the 'false' bucket.");
-  Assert.equal(s.values[1], 0, "No probes in the 'true' bucket.");
+  Assert.equal(s.counts[0], 1, "One probe for the 'false' bucket.");
+  Assert.equal(s.counts[1], 0, "No probes in the 'true' bucket.");
 });
 
 /**
@@ -85,8 +85,8 @@ add_task(async function test_one_file_valid() {
   // Checking if the histogram is updated negatively.
   let h = Telemetry.getHistogramById(HistogramId);
   let s = h.snapshot();
-  Assert.equal(s.values[0], 1, "One probe for the 'false' bucket.");
-  Assert.equal(s.values[1], 0, "No probes in the 'true' bucket.");
+  Assert.equal(s.counts[0], 1, "One probe for the 'false' bucket.");
+  Assert.equal(s.counts[1], 0, "No probes in the 'true' bucket.");
 });
 
 /**
@@ -107,6 +107,6 @@ add_task(async function test_all_files_corrupt() {
   // Checking if the histogram is positively updated.
   let h = Telemetry.getHistogramById(HistogramId);
   let s = h.snapshot();
-  Assert.equal(s.values[1], 1, "One probe for the 'true' bucket.");
-  Assert.equal(s.values[0], 0, "No probes in the 'false' bucket.");
+  Assert.equal(s.counts[1], 1, "One probe for the 'true' bucket.");
+  Assert.equal(s.counts[0], 0, "No probes in the 'false' bucket.");
 });

browser/components/translation/test/browser_translation_telemetry.js

@@ -39,8 +39,8 @@ var MetricsChecker = {
       deniedOffers: this.HISTOGRAMS.DENIED.snapshot().sum || 0,
       autoRejectedOffers: this.HISTOGRAMS.AUTO_REJECTED.snapshot().sum || 0,
       showOriginal: this.HISTOGRAMS.SHOW_ORIGINAL.snapshot().sum || 0,
-      detectedLanguageChangedBefore: this.HISTOGRAMS.DETECTION_CHANGES.snapshot().values[1] || 0,
-      detectedLanguageChangeAfter: this.HISTOGRAMS.DETECTION_CHANGES.snapshot().values[0] || 0,
+      detectedLanguageChangedBefore: this.HISTOGRAMS.DETECTION_CHANGES.snapshot().counts[1] || 0,
+      detectedLanguageChangeAfter: this.HISTOGRAMS.DETECTION_CHANGES.snapshot().counts[0] || 0,
       targetLanguageChanged: this.HISTOGRAMS.TARGET_CHANGES.snapshot().sum || 0,
       showUI: this.HISTOGRAMS.SHOW_UI.snapshot().sum || 0,
       detectLang: this.HISTOGRAMS.DETECT_LANG.snapshot().sum || 0,

browser/modules/test/browser/browser_UsageTelemetry.js

@@ -137,19 +137,20 @@ add_task(async function test_subsessionSplit() {
 });
 
 function checkTabCountHistogram(result, expected, message) {
-  Assert.deepEqual(result.values, expected, message);
+  let expectedPadded = result.counts.map((val, idx) => idx < expected.length ? expected[idx] : 0);
+  Assert.deepEqual(result.counts, expectedPadded, message);
 }
 
 add_task(async function test_tabsHistogram() {
   let openedTabs = [];
   let tabCountHist = getAndClearHistogram("TAB_COUNT");
 
-  checkTabCountHistogram(tabCountHist.snapshot(), {}, "TAB_COUNT telemetry - initial tab counts");
+  checkTabCountHistogram(tabCountHist.snapshot(), [0, 0], "TAB_COUNT telemetry - initial tab counts");
 
   // Add a new tab and check that the count is right.
   BrowserUsageTelemetry._lastRecordTabCount = 0;
   openedTabs.push(await BrowserTestUtils.openNewForegroundTab(gBrowser, "about:blank"));
-  checkTabCountHistogram(tabCountHist.snapshot(), {1: 0, 2: 1, 3: 0}, "TAB_COUNT telemetry - opening tabs");
+  checkTabCountHistogram(tabCountHist.snapshot(), [0, 0, 1], "TAB_COUNT telemetry - opening tabs");
 
   // Open a different page and check the counts.
   BrowserUsageTelemetry._lastRecordTabCount = 0;
@@ -158,24 +159,24 @@ add_task(async function test_tabsHistogram() {
   BrowserUsageTelemetry._lastRecordTabCount = 0;
   await BrowserTestUtils.loadURI(tab.linkedBrowser, "http://example.com/");
   await BrowserTestUtils.browserLoaded(tab.linkedBrowser);
-  checkTabCountHistogram(tabCountHist.snapshot(), {1: 0, 2: 1, 3: 2, 4: 0}, "TAB_COUNT telemetry - loading page");
+  checkTabCountHistogram(tabCountHist.snapshot(), [0, 0, 1, 2], "TAB_COUNT telemetry - loading page");
 
   // Open another tab
   BrowserUsageTelemetry._lastRecordTabCount = 0;
   openedTabs.push(await BrowserTestUtils.openNewForegroundTab(gBrowser, "about:blank"));
-  checkTabCountHistogram(tabCountHist.snapshot(), {1: 0, 2: 1, 3: 2, 4: 1, 5: 0}, "TAB_COUNT telemetry - opening more tabs");
+  checkTabCountHistogram(tabCountHist.snapshot(), [0, 0, 1, 2, 1], "TAB_COUNT telemetry - opening more tabs");
 
   // Add a new window and then some tabs in it. A new window starts with one tab.
   BrowserUsageTelemetry._lastRecordTabCount = 0;
   let win = await BrowserTestUtils.openNewBrowserWindow();
-  checkTabCountHistogram(tabCountHist.snapshot(), {1: 0, 2: 1, 3: 2, 4: 1, 5: 1, 6: 0}, "TAB_COUNT telemetry - opening window");
+  checkTabCountHistogram(tabCountHist.snapshot(), [0, 0, 1, 2, 1, 1], "TAB_COUNT telemetry - opening window");
 
   // Do not trigger a recount if _lastRecordTabCount is recent on new tab
   BrowserUsageTelemetry._lastRecordTabCount = Date.now() - (MINIMUM_TAB_COUNT_INTERVAL_MS / 2);
   {
     let oldLastRecordTabCount = BrowserUsageTelemetry._lastRecordTabCount;
     openedTabs.push(await BrowserTestUtils.openNewForegroundTab(win.gBrowser, "about:blank"));
-    checkTabCountHistogram(tabCountHist.snapshot(), {1: 0, 2: 1, 3: 2, 4: 1, 5: 1, 6: 0}, "TAB_COUNT telemetry - new tab, recount event ignored");
+    checkTabCountHistogram(tabCountHist.snapshot(), [0, 0, 1, 2, 1, 1, 0], "TAB_COUNT telemetry - new tab, recount event ignored");
     ok(BrowserUsageTelemetry._lastRecordTabCount == oldLastRecordTabCount, "TAB_COUNT telemetry - _lastRecordTabCount unchanged");
   }
 
@@ -184,7 +185,7 @@ add_task(async function test_tabsHistogram() {
   {
     let oldLastRecordTabCount = BrowserUsageTelemetry._lastRecordTabCount;
     openedTabs.push(await BrowserTestUtils.openNewForegroundTab(win.gBrowser, "about:blank"));
-    checkTabCountHistogram(tabCountHist.snapshot(), {1: 0, 2: 1, 3: 2, 4: 1, 5: 1, 7: 1, 8: 0}, "TAB_COUNT telemetry - new tab, recount event included");
+    checkTabCountHistogram(tabCountHist.snapshot(), [0, 0, 1, 2, 1, 1, 0, 1], "TAB_COUNT telemetry - new tab, recount event included");
     ok(BrowserUsageTelemetry._lastRecordTabCount != oldLastRecordTabCount, "TAB_COUNT telemetry - _lastRecordTabCount updated");
     ok(BrowserUsageTelemetry._lastRecordTabCount > Date.now() - MINIMUM_TAB_COUNT_INTERVAL_MS, "TAB_COUNT telemetry - _lastRecordTabCount invariant");
   }
@@ -195,7 +196,7 @@ add_task(async function test_tabsHistogram() {
     let oldLastRecordTabCount = BrowserUsageTelemetry._lastRecordTabCount;
     await BrowserTestUtils.loadURI(tab.linkedBrowser, "http://example.com/");
     await BrowserTestUtils.browserLoaded(tab.linkedBrowser);
-    checkTabCountHistogram(tabCountHist.snapshot(), {1: 0, 2: 1, 3: 2, 4: 1, 5: 1, 7: 1, 8: 0}, "TAB_COUNT telemetry - page load, recount event ignored");
+    checkTabCountHistogram(tabCountHist.snapshot(), [0, 0, 1, 2, 1, 1, 0, 1], "TAB_COUNT telemetry - page load, recount event ignored");
     ok(BrowserUsageTelemetry._lastRecordTabCount == oldLastRecordTabCount, "TAB_COUNT telemetry - _lastRecordTabCount unchanged");
   }
 
@@ -205,7 +206,7 @@ add_task(async function test_tabsHistogram() {
     let oldLastRecordTabCount = BrowserUsageTelemetry._lastRecordTabCount;
     await BrowserTestUtils.loadURI(tab.linkedBrowser, "http://example.com/");
     await BrowserTestUtils.browserLoaded(tab.linkedBrowser);
-    checkTabCountHistogram(tabCountHist.snapshot(), {1: 0, 2: 1, 3: 2, 4: 1, 5: 1, 7: 2, 8: 0}, "TAB_COUNT telemetry - page load, recount event included");
+    checkTabCountHistogram(tabCountHist.snapshot(), [0, 0, 1, 2, 1, 1, 0, 2], "TAB_COUNT telemetry - page load, recount event included");
     ok(BrowserUsageTelemetry._lastRecordTabCount != oldLastRecordTabCount, "TAB_COUNT telemetry - _lastRecordTabCount updated");
     ok(BrowserUsageTelemetry._lastRecordTabCount > Date.now() - MINIMUM_TAB_COUNT_INTERVAL_MS, "TAB_COUNT telemetry - _lastRecordTabCount invariant");
   }

browser/modules/test/browser/browser_UsageTelemetry_searchbar.js

@@ -9,12 +9,12 @@ ChromeUtils.import("resource://testing-common/CustomizableUITestUtils.jsm", this
 let gCUITestUtils = new CustomizableUITestUtils(window);
 
 function checkHistogramResults(resultIndexes, expected, histogram) {
-  for (let [i, val] of Object.entries(resultIndexes.values)) {
+  for (let i = 0; i < resultIndexes.counts.length; i++) {
     if (i == expected) {
-      Assert.equal(val, 1,
+      Assert.equal(resultIndexes.counts[i], 1,
         `expected counts should match for ${histogram} index ${i}`);
     } else {
-      Assert.equal(!!val, false,
+      Assert.equal(resultIndexes.counts[i], 0,
         `unexpected counts should be zero for ${histogram} index ${i}`);
     }
   }

browser/modules/test/browser/browser_UsageTelemetry_urlbar.js

@@ -15,12 +15,12 @@ ChromeUtils.defineModuleGetter(this, "URLBAR_SELECTED_RESULT_METHODS",
                                "resource:///modules/BrowserUsageTelemetry.jsm");
 
 function checkHistogramResults(resultIndexes, expected, histogram) {
-  for (let [i, val] of Object.entries(resultIndexes.values)) {
+  for (let i = 0; i < resultIndexes.counts.length; i++) {
     if (i == expected) {
-      Assert.equal(val, 1,
+      Assert.equal(resultIndexes.counts[i], 1,
         `expected counts should match for ${histogram} index ${i}`);
     } else {
-      Assert.equal(!!val, false,
+      Assert.equal(resultIndexes.counts[i], 0,
         `unexpected counts should be zero for ${histogram} index ${i}`);
     }
   }

devtools/client/framework/test/browser_toolbox_hosts_telemetry.js

@@ -41,5 +41,5 @@ function checkResults() {
   //   - 2 "left" entries.
   //   - 3 "right" entries.
   //   - 2 "window" entries.
-  checkTelemetry("DEVTOOLS_TOOLBOX_HOST", "", {0: 3, 1: 3, 2: 2, 4: 2, 5: 0}, "array");
+  checkTelemetry("DEVTOOLS_TOOLBOX_HOST", "", [3, 3, 2, 0, 2, 0, 0, 0, 0, 0], "array");
 }

devtools/client/inspector/grids/test/browser_grids_number-of-css-grids-telemetry.js

@@ -44,5 +44,6 @@ function checkResults() {
   // Check for:
   //   - 1 CSS Grid Element
   checkTelemetry("DEVTOOLS_NUMBER_OF_CSS_GRIDS_IN_A_PAGE", "",
-    {0: 0, 1: 1, 2: 0}, "array");
+    [0, 1, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0,
+     0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0], "array");
 }

devtools/client/performance/test/browser_perf-telemetry-01.js

@@ -39,18 +39,14 @@ add_task(async function() {
 function checkResults() {
   // For help generating these tests use generateTelemetryTests("DEVTOOLS_PERFTOOLS_")
   // here.
-  checkTelemetry("DEVTOOLS_PERFTOOLS_RECORDING_COUNT", "", {0: 2, 1: 0}, "array");
+  checkTelemetry("DEVTOOLS_PERFTOOLS_RECORDING_COUNT", "", [2, 0, 0], "array");
   checkTelemetry("DEVTOOLS_PERFTOOLS_RECORDING_DURATION_MS", "", null, "hasentries");
   checkTelemetry(
-    "DEVTOOLS_PERFTOOLS_RECORDING_FEATURES_USED", "withMarkers", {0: 0, 1: 2, 2: 0},
-    "array");
+    "DEVTOOLS_PERFTOOLS_RECORDING_FEATURES_USED", "withMarkers", [0, 2, 0], "array");
   checkTelemetry(
-    "DEVTOOLS_PERFTOOLS_RECORDING_FEATURES_USED", "withMemory", {0: 1, 1: 1, 2: 0},
-    "array");
+    "DEVTOOLS_PERFTOOLS_RECORDING_FEATURES_USED", "withMemory", [1, 1, 0], "array");
   checkTelemetry(
-    "DEVTOOLS_PERFTOOLS_RECORDING_FEATURES_USED", "withAllocations", {0: 2, 1: 0},
-    "array");
+    "DEVTOOLS_PERFTOOLS_RECORDING_FEATURES_USED", "withAllocations", [2, 0, 0], "array");
   checkTelemetry(
-    "DEVTOOLS_PERFTOOLS_RECORDING_FEATURES_USED", "withTicks", {0: 0, 1: 2, 2: 0},
-    "array");
+    "DEVTOOLS_PERFTOOLS_RECORDING_FEATURES_USED", "withTicks", [0, 2, 0], "array");
 }

devtools/client/performance/test/browser_perf-telemetry-02.js

@@ -44,8 +44,6 @@ add_task(async function() {
 function checkResults() {
   // For help generating these tests use generateTelemetryTests("DEVTOOLS_PERFTOOLS_")
   // here.
-  checkTelemetry("DEVTOOLS_PERFTOOLS_RECORDING_IMPORT_FLAG", "", {0: 0, 1: 1, 2: 0},
-    "array");
-  checkTelemetry("DEVTOOLS_PERFTOOLS_RECORDING_EXPORT_FLAG", "", {0: 0, 1: 1, 2: 0},
-    "array");
+  checkTelemetry("DEVTOOLS_PERFTOOLS_RECORDING_IMPORT_FLAG", "", [0, 1, 0], "array");
+  checkTelemetry("DEVTOOLS_PERFTOOLS_RECORDING_EXPORT_FLAG", "", [0, 1, 0], "array");
 }

devtools/client/performance/test/browser_perf-telemetry-04.js

@@ -41,17 +41,14 @@ add_task(async function() {
 function checkResults() {
   // For help generating these tests use generateTelemetryTests("DEVTOOLS_PERFTOOLS_")
   // here.
-  checkTelemetry("DEVTOOLS_PERFTOOLS_CONSOLE_RECORDING_COUNT", "", {0: 1, 1: 0}, "array");
+  checkTelemetry("DEVTOOLS_PERFTOOLS_CONSOLE_RECORDING_COUNT", "", [1, 0, 0], "array");
   checkTelemetry("DEVTOOLS_PERFTOOLS_RECORDING_DURATION_MS", "", null, "hasentries");
   checkTelemetry(
-    "DEVTOOLS_PERFTOOLS_RECORDING_FEATURES_USED", "withMarkers", {0: 0, 1: 1, 2: 0},
-    "array");
+    "DEVTOOLS_PERFTOOLS_RECORDING_FEATURES_USED", "withMarkers", [0, 1, 0], "array");
   checkTelemetry(
-    "DEVTOOLS_PERFTOOLS_RECORDING_FEATURES_USED", "withMemory", {0: 1, 1: 0}, "array");
+    "DEVTOOLS_PERFTOOLS_RECORDING_FEATURES_USED", "withMemory", [1, 0, 0], "array");
   checkTelemetry(
-    "DEVTOOLS_PERFTOOLS_RECORDING_FEATURES_USED", "withAllocations", {0: 1, 1: 0},
-    "array");
+    "DEVTOOLS_PERFTOOLS_RECORDING_FEATURES_USED", "withAllocations", [1, 0, 0], "array");
   checkTelemetry(
-    "DEVTOOLS_PERFTOOLS_RECORDING_FEATURES_USED", "withTicks", {0: 0, 1: 1, 2: 0},
-    "array");
+    "DEVTOOLS_PERFTOOLS_RECORDING_FEATURES_USED", "withTicks", [0, 1, 0], "array");
 }

devtools/client/shared/test/browser_telemetry_button_paintflashing.js

@@ -52,6 +52,6 @@ async function delayedClicks(toolbox, node, clicks) {
 function checkResults() {
   // For help generating these tests use generateTelemetryTests("DEVTOOLS_PAINTFLASHING_")
   // here.
-  checkTelemetry("DEVTOOLS_PAINTFLASHING_OPENED_COUNT", "", {0: 2, 1: 0}, "array");
+  checkTelemetry("DEVTOOLS_PAINTFLASHING_OPENED_COUNT", "", [2, 0, 0], "array");
   checkTelemetry("DEVTOOLS_PAINTFLASHING_TIME_ACTIVE_SECONDS", "", null, "hasentries");
 }

devtools/client/shared/test/browser_telemetry_button_responsive.js

@@ -84,6 +84,6 @@ var delayedClicks = async function(node, clicks) {
 function checkResults() {
   // For help generating these tests use generateTelemetryTests("DEVTOOLS_RESPONSIVE_")
   // here.
-  checkTelemetry("DEVTOOLS_RESPONSIVE_OPENED_COUNT", "", {0: 2, 1: 0}, "array");
+  checkTelemetry("DEVTOOLS_RESPONSIVE_OPENED_COUNT", "", [2, 0, 0], "array");
   checkTelemetry("DEVTOOLS_RESPONSIVE_TIME_ACTIVE_SECONDS", "", null, "hasentries");
 }

devtools/client/shared/test/browser_telemetry_button_scratchpad.js

@@ -97,5 +97,5 @@ function delayedClicks(node, clicks) {
 function checkResults() {
   // For help generating these tests use generateTelemetryTests("DEVTOOLS_SCRATCHPAD_")
   // here.
-  checkTelemetry("DEVTOOLS_SCRATCHPAD_WINDOW_OPENED_COUNT", "", {0: 4, 1: 0}, "array");
+  checkTelemetry("DEVTOOLS_SCRATCHPAD_WINDOW_OPENED_COUNT", "", [4, 0, 0], "array");
 }

devtools/client/shared/test/browser_telemetry_misc.js

@@ -20,9 +20,9 @@ add_task(async function() {
 function checkResults() {
   // For help generating these tests use generateTelemetryTests("DEVTOOLS_")
   // here.
-  checkTelemetry("DEVTOOLS_TOOLBOX_OPENED_COUNT", "", {0: 1, 1: 0}, "array");
-  checkTelemetry("DEVTOOLS_INSPECTOR_OPENED_COUNT", "", {0: 1, 1: 0}, "array");
-  checkTelemetry("DEVTOOLS_RULEVIEW_OPENED_COUNT", "", {0: 1, 1: 0}, "array");
+  checkTelemetry("DEVTOOLS_TOOLBOX_OPENED_COUNT", "", [1, 0, 0], "array");
+  checkTelemetry("DEVTOOLS_INSPECTOR_OPENED_COUNT", "", [1, 0, 0], "array");
+  checkTelemetry("DEVTOOLS_RULEVIEW_OPENED_COUNT", "", [1, 0, 0], "array");
   checkTelemetry("DEVTOOLS_TOOLBOX_TIME_ACTIVE_SECONDS", "", null, "hasentries");
   checkTelemetry("DEVTOOLS_INSPECTOR_TIME_ACTIVE_SECONDS", "", null, "hasentries");
   checkTelemetry("DEVTOOLS_RULEVIEW_TIME_ACTIVE_SECONDS", "", null, "hasentries");

devtools/client/shared/test/browser_telemetry_sidebar.js

@@ -154,11 +154,11 @@ function testSidebar(toolbox) {
 function checkResults() {
   // For help generating these tests use generateTelemetryTests("DEVTOOLS_")
   // here.
-  checkTelemetry("DEVTOOLS_INSPECTOR_OPENED_COUNT", "", {0: 1, 1: 0}, "array");
-  checkTelemetry("DEVTOOLS_RULEVIEW_OPENED_COUNT", "", {0: 1, 1: 0}, "array");
-  checkTelemetry("DEVTOOLS_COMPUTEDVIEW_OPENED_COUNT", "", {0: 2, 1: 0}, "array");
-  checkTelemetry("DEVTOOLS_LAYOUTVIEW_OPENED_COUNT", "", {0: 3, 1: 0}, "array");
-  checkTelemetry("DEVTOOLS_FONTINSPECTOR_OPENED_COUNT", "", {0: 2, 1: 0}, "array");
+  checkTelemetry("DEVTOOLS_INSPECTOR_OPENED_COUNT", "", [1, 0, 0], "array");
+  checkTelemetry("DEVTOOLS_RULEVIEW_OPENED_COUNT", "", [1, 0, 0], "array");
+  checkTelemetry("DEVTOOLS_COMPUTEDVIEW_OPENED_COUNT", "", [2, 0, 0], "array");
+  checkTelemetry("DEVTOOLS_LAYOUTVIEW_OPENED_COUNT", "", [3, 0, 0], "array");
+  checkTelemetry("DEVTOOLS_FONTINSPECTOR_OPENED_COUNT", "", [2, 0, 0], "array");
   checkTelemetry("DEVTOOLS_COMPUTEDVIEW_TIME_ACTIVE_SECONDS", "", null, "hasentries");
   checkTelemetry("DEVTOOLS_LAYOUTVIEW_TIME_ACTIVE_SECONDS", "", null, "hasentries");
   checkTelemetry("DEVTOOLS_FONTINSPECTOR_TIME_ACTIVE_SECONDS", "", null, "hasentries");

devtools/client/shared/test/browser_telemetry_toolbox.js

@@ -23,7 +23,7 @@ add_task(async function() {
 function checkResults() {
   // For help generating these tests use generateTelemetryTests("DEVTOOLS_TOOLBOX_")
   // here.
-  checkTelemetry("DEVTOOLS_TOOLBOX_OPENED_COUNT", "", {0: 3, 1: 0}, "array");
+  checkTelemetry("DEVTOOLS_TOOLBOX_OPENED_COUNT", "", [3, 0, 0], "array");
   checkTelemetry("DEVTOOLS_TOOLBOX_TIME_ACTIVE_SECONDS", "", null, "hasentries");
   checkTelemetry("DEVTOOLS_TOOLBOX_HOST", "", null, "hasentries");
 }

devtools/client/shared/test/browser_telemetry_toolboxtabs_canvasdebugger.js

@@ -30,6 +30,6 @@ add_task(async function() {
 function checkResults() {
   // For help generating these tests use generateTelemetryTests("DEVTOOLS_CANVASDEBUGGER")
   // here.
-  checkTelemetry("DEVTOOLS_CANVASDEBUGGER_OPENED_COUNT", "", {0: 2, 1: 0}, "array");
+  checkTelemetry("DEVTOOLS_CANVASDEBUGGER_OPENED_COUNT", "", [2, 0, 0], "array");
   checkTelemetry("DEVTOOLS_CANVASDEBUGGER_TIME_ACTIVE_SECONDS", "", null, "hasentries");
 }

devtools/client/shared/test/browser_telemetry_toolboxtabs_inspector.js

@@ -23,6 +23,6 @@ add_task(async function() {
 function checkResults() {
   // For help generating these tests use generateTelemetryTests("DEVTOOLS_INSPECTOR_")
   // here.
-  checkTelemetry("DEVTOOLS_INSPECTOR_OPENED_COUNT", "", {0: 2, 1: 0}, "array");
+  checkTelemetry("DEVTOOLS_INSPECTOR_OPENED_COUNT", "", [2, 0, 0], "array");
   checkTelemetry("DEVTOOLS_INSPECTOR_TIME_ACTIVE_SECONDS", "", null, "hasentries");
 }

devtools/client/shared/test/browser_telemetry_toolboxtabs_jsdebugger.js

@@ -23,6 +23,6 @@ add_task(async function() {
 function checkResults() {
   // For help generating these tests use generateTelemetryTests("DEVTOOLS_JSDEBUGGER_")
   // here.
-  checkTelemetry("DEVTOOLS_JSDEBUGGER_OPENED_COUNT", "", {0: 2, 1: 0}, "array");
+  checkTelemetry("DEVTOOLS_JSDEBUGGER_OPENED_COUNT", "", [2, 0, 0], "array");
   checkTelemetry("DEVTOOLS_JSDEBUGGER_TIME_ACTIVE_SECONDS", "", null, "hasentries");
 }

devtools/client/shared/test/browser_telemetry_toolboxtabs_jsprofiler.js

@@ -23,6 +23,6 @@ add_task(async function() {
 function checkResults() {
   // For help generating these tests use generateTelemetryTests("DEVTOOLS_JSPROFILER")
   // here.
-  checkTelemetry("DEVTOOLS_JSPROFILER_OPENED_COUNT", "", {0: 2, 1: 0}, "array");
+  checkTelemetry("DEVTOOLS_JSPROFILER_OPENED_COUNT", "", [2, 0, 0], "array");
   checkTelemetry("DEVTOOLS_JSPROFILER_TIME_ACTIVE_SECONDS", "", null, "hasentries");
 }

devtools/client/shared/test/browser_telemetry_toolboxtabs_netmonitor.js

@@ -23,6 +23,6 @@ add_task(async function() {
 function checkResults() {
   // For help generating these tests use generateTelemetryTests("DEVTOOLS_NETMONITOR_")
   // here.
-  checkTelemetry("DEVTOOLS_NETMONITOR_OPENED_COUNT", "", {0: 2, 1: 0}, "array");
+  checkTelemetry("DEVTOOLS_NETMONITOR_OPENED_COUNT", "", [2, 0, 0], "array");
   checkTelemetry("DEVTOOLS_NETMONITOR_TIME_ACTIVE_SECONDS", "", null, "hasentries");
 }

devtools/client/shared/test/browser_telemetry_toolboxtabs_options.js

@@ -23,6 +23,6 @@ add_task(async function() {
 function checkResults() {
   // For help generating these tests use generateTelemetryTests("DEVTOOLS_OPTIONS_")
   // here.
-  checkTelemetry("DEVTOOLS_OPTIONS_OPENED_COUNT", "", {0: 2, 1: 0}, "array");
+  checkTelemetry("DEVTOOLS_OPTIONS_OPENED_COUNT", "", [2, 0, 0], "array");
   checkTelemetry("DEVTOOLS_OPTIONS_TIME_ACTIVE_SECONDS", "", null, "hasentries");
 }

devtools/client/shared/test/browser_telemetry_toolboxtabs_shadereditor.js

@@ -31,6 +31,6 @@ add_task(async function() {
 function checkResults() {
   // For help generating these tests use generateTelemetryTests("DEVTOOLS_SHADEREDITOR_")
   // here.
-  checkTelemetry("DEVTOOLS_SHADEREDITOR_OPENED_COUNT", "", {0: 2, 1: 0}, "array");
+  checkTelemetry("DEVTOOLS_SHADEREDITOR_OPENED_COUNT", "", [2, 0, 0], "array");
   checkTelemetry("DEVTOOLS_SHADEREDITOR_TIME_ACTIVE_SECONDS", "", null, "hasentries");
 }

devtools/client/shared/test/browser_telemetry_toolboxtabs_storage.js

@@ -23,6 +23,6 @@ add_task(async function() {
 function checkResults() {
   // For help generating these tests use generateTelemetryTests("DEVTOOLS_STORAGE_")
   // here.
-  checkTelemetry("DEVTOOLS_STORAGE_OPENED_COUNT", "", {0: 2, 1: 0}, "array");
+  checkTelemetry("DEVTOOLS_STORAGE_OPENED_COUNT", "", [2, 0, 0], "array");
   checkTelemetry("DEVTOOLS_STORAGE_TIME_ACTIVE_SECONDS", "", null, "hasentries");
 }

devtools/client/shared/test/browser_telemetry_toolboxtabs_styleeditor.js

@@ -23,6 +23,6 @@ add_task(async function() {
 function checkResults() {
   // For help generating these tests use generateTelemetryTests("DEVTOOLS_STYLEEDITOR_")
   // here.
-  checkTelemetry("DEVTOOLS_STYLEEDITOR_OPENED_COUNT", "", {0: 2, 1: 0}, "array");
+  checkTelemetry("DEVTOOLS_STYLEEDITOR_OPENED_COUNT", "", [2, 0, 0], "array");
   checkTelemetry("DEVTOOLS_STYLEEDITOR_TIME_ACTIVE_SECONDS", "", null, "hasentries");
 }

devtools/client/shared/test/browser_telemetry_toolboxtabs_webaudioeditor.js

@@ -30,6 +30,6 @@ add_task(async function() {
 function checkResults() {
   // For help generating these tests use generateTelemetryTests("DEVTOOLS_WEBAUDIOEDITOR")
   // here.
-  checkTelemetry("DEVTOOLS_WEBAUDIOEDITOR_OPENED_COUNT", "", {0: 2, 1: 0}, "array");
+  checkTelemetry("DEVTOOLS_WEBAUDIOEDITOR_OPENED_COUNT", "", [2, 0, 0], "array");
   checkTelemetry("DEVTOOLS_WEBAUDIOEDITOR_TIME_ACTIVE_SECONDS", "", null, "hasentries");
 }

devtools/client/shared/test/browser_telemetry_toolboxtabs_webconsole.js

@@ -23,6 +23,6 @@ add_task(async function() {
 function checkResults() {
   // For help generating these tests use generateTelemetryTests("DEVTOOLS_WEBCONSOLE_")
   // here.
-  checkTelemetry("DEVTOOLS_WEBCONSOLE_OPENED_COUNT", "", {0: 2, 1: 0}, "array");
+  checkTelemetry("DEVTOOLS_WEBCONSOLE_OPENED_COUNT", "", [2, 0, 0], "array");
   checkTelemetry("DEVTOOLS_WEBCONSOLE_TIME_ACTIVE_SECONDS", "", null, "hasentries");
 }

devtools/client/shared/test/telemetry-test-helpers.js

@@ -103,13 +103,13 @@ class TelemetryHelpers {
         const result = keyedHistogram[key];
 
         if (result) {
-          actual = result.values;
+          actual = result.counts;
         } else {
           ok(false, `${histId}[${key}] exists`);
           return;
         }
       } else {
-        actual = Services.telemetry.getHistogramById(histId).snapshot().values;
+        actual = Services.telemetry.getHistogramById(histId).snapshot().counts;
       }
     }
 
@@ -119,7 +119,7 @@ class TelemetryHelpers {
         is(JSON.stringify(actual), JSON.stringify(expected), msg);
         break;
       case "hasentries":
-        const hasEntry = Object.values(actual).some(num => num > 0);
+        const hasEntry = actual.some(num => num > 0);
         if (key) {
           ok(hasEntry, `${histId}["${key}"] has at least one entry.`);
         } else {

dom/webauthn/tests/browser/browser_webauthn_telemetry.js

@@ -30,7 +30,10 @@ function validateHistogramEntryCount(aHistogramName, aExpectedCount) {
   let hist = Services.telemetry.getHistogramById(aHistogramName);
   let resultIndexes = hist.snapshot();
 
-  let entriesSeen = Object.values(resultIndexes.values).reduce((a,b) => a + b, 0);
+  let entriesSeen = 0;
+  for (let i = 0; i < resultIndexes.counts.length; i++) {
+    entriesSeen += resultIndexes.counts[i];
+  }
 
   is(entriesSeen, aExpectedCount, "Expecting " + aExpectedCount + " histogram entries in " +
      aHistogramName);

toolkit/components/telemetry/app/TelemetryUtils.jsm

@@ -26,6 +26,57 @@ const IS_CONTENT_PROCESS = (function() {
   return runtime.processType == Ci.nsIXULRuntime.PROCESS_TYPE_CONTENT;
 })();
 
+/**
+ * When reflecting a histogram into JS, Telemetry hands us an object
+ * with the following properties:
+ *
+ * - min, max, histogram_type, sum, sum_squares_{lo,hi}: simple integers;
+ * - counts: array of counts for histogram buckets;
+ * - ranges: array of calculated bucket sizes.
+ *
+ * This format is not straightforward to read and potentially bulky
+ * with lots of zeros in the counts array.  Packing histograms makes
+ * raw histograms easier to read and compresses the data a little bit.
+ *
+ * Returns an object:
+ * { range: [min, max], bucket_count: <number of buckets>,
+ *   histogram_type: <histogram_type>, sum: <sum>,
+ *   values: { bucket1: count1, bucket2: count2, ... } }
+ */
+function packHistogram(hgram) {
+  let r = hgram.ranges;
+  let c = hgram.counts;
+  let retgram = {
+    range: [r[1], r[r.length - 1]],
+    bucket_count: r.length,
+    histogram_type: hgram.histogram_type,
+    values: {},
+    sum: hgram.sum,
+  };
+
+  let first = true;
+  let last = 0;
+
+  for (let i = 0; i < c.length; i++) {
+    let value = c[i];
+    if (!value)
+      continue;
+
+    // add a lower bound
+    if (i && first) {
+      retgram.values[r[i - 1]] = 0;
+    }
+    first = false;
+    last = i + 1;
+    retgram.values[r[i]] = value;
+  }
+
+  // add an upper bound
+  if (last && last < c.length)
+    retgram.values[r[last]] = 0;
+  return retgram;
+}
+
 var TelemetryUtils = {
   Preferences: Object.freeze({
     // General Preferences
@@ -273,7 +324,7 @@ var TelemetryUtils = {
       ret[process] = {};
       for (let [name, value] of Object.entries(histograms)) {
         if (testingMode || !name.startsWith("TELEMETRY_TEST_")) {
-          ret[process][name] = value;
+          ret[process][name] = packHistogram(value);
         }
       }
     }
@@ -322,7 +373,7 @@ var TelemetryUtils = {
           }
           ret[process][name] = {};
           for (let [key, hgram] of Object.entries(value)) {
-            ret[process][name][key] = hgram;
+            ret[process][name][key] = packHistogram(hgram);
           }
         }
       }

toolkit/components/telemetry/core/TelemetryHistogram.cpp

@@ -747,25 +747,16 @@ internal_GetHistogramAndSamples(const StaticMutexAutoLock& aLock,
   return NS_OK;
 }
 
-/**
- * Reflect a histogram snapshot into a JavaScript object.
- * The returned histogram object will have the following properties:
- *
- *   bucket_count - Number of buckets of this histogram
- *   histogram_type - HISTOGRAM_EXPONENTIAL, HISTOGRAM_LINEAR, HISTOGRAM_BOOLEAN,
- *                    HISTOGRAM_FLAG, HISTOGRAM_COUNT, or HISTOGRAM_CATEGORICAL
- *   sum - sum of the bucket contents
- *   range - A 2-item array of minimum and maximum bucket size
- *   values - Map from bucket start to the bucket's count
- */
 nsresult
 internal_ReflectHistogramAndSamples(JSContext *cx,
                                     JS::Handle<JSObject*> obj,
                                     const HistogramInfo& aHistogramInfo,
                                     const HistogramSnapshotData& aSnapshot)
 {
-  if (!(JS_DefineProperty(cx, obj, "bucket_count",
-                             aHistogramInfo.bucketCount, JSPROP_ENUMERATE)
+  if (!(JS_DefineProperty(cx, obj, "min",
+                          aHistogramInfo.min, JSPROP_ENUMERATE)
+        && JS_DefineProperty(cx, obj, "max",
+                             aHistogramInfo.max, JSPROP_ENUMERATE)
         && JS_DefineProperty(cx, obj, "histogram_type",
                              aHistogramInfo.histogramType, JSPROP_ENUMERATE)
         && JS_DefineProperty(cx, obj, "sum",
@@ -780,54 +771,29 @@ internal_ReflectHistogramAndSamples(JSContext *cx,
   MOZ_ASSERT(count == aSnapshot.mBucketRanges.Length(),
              "The number of buckets and the number of counts must match.");
 
-  // Create the "range" property and add it to the final object.
-  JS::Rooted<JSObject*> rarray(cx, JS_NewArrayObject(cx, 2));
-  if (rarray == nullptr
-      || !JS_DefineProperty(cx, obj, "range", rarray, JSPROP_ENUMERATE)) {
-    return NS_ERROR_FAILURE;
-  }
-  // Add [min, max] into the range array
-  if (!JS_DefineElement(cx, rarray, 0, aHistogramInfo.min, JSPROP_ENUMERATE)) {
-    return NS_ERROR_FAILURE;
-  }
-  if (!JS_DefineElement(cx, rarray, 1, aHistogramInfo.max, JSPROP_ENUMERATE)) {
+  // Create the "ranges" property and add it to the final object.
+  JS::Rooted<JSObject*> rarray(cx, JS_NewArrayObject(cx, count));
+  if (!rarray
+      || !JS_DefineProperty(cx, obj, "ranges", rarray, JSPROP_ENUMERATE)) {
     return NS_ERROR_FAILURE;
   }
 
-  JS::Rooted<JSObject*> values(cx, JS_NewPlainObject(cx));
-  if (values == nullptr
-      || !JS_DefineProperty(cx, obj, "values", values, JSPROP_ENUMERATE)) {
-    return NS_ERROR_FAILURE;
-  }
-
-  bool first = true;
-  size_t last = 0;
-
+  // Fill the "ranges" property.
   for (size_t i = 0; i < count; i++) {
-    auto value = aSnapshot.mBucketCounts[i];
-    if (value == 0) {
-      continue;
-    }
-
-    if (i > 0 && first) {
-      auto range = aSnapshot.mBucketRanges[i - 1];
-      if (!JS_DefineProperty(cx, values, nsPrintfCString("%d", range).get(), 0, JSPROP_ENUMERATE)) {
-        return NS_ERROR_FAILURE;
-      }
-    }
-
-    first = false;
-    last = i + 1;
-
-    auto range = aSnapshot.mBucketRanges[i];
-    if (!JS_DefineProperty(cx, values, nsPrintfCString("%d", range).get(), value, JSPROP_ENUMERATE)) {
+    if (!JS_DefineElement(cx, rarray, i, aSnapshot.mBucketRanges[i], JSPROP_ENUMERATE)) {
       return NS_ERROR_FAILURE;
     }
   }
 
-  if (last > 0 && last < count) {
-    auto range = aSnapshot.mBucketRanges[last];
-    if (!JS_DefineProperty(cx, values, nsPrintfCString("%d", range).get(), 0, JSPROP_ENUMERATE)) {
+  JS::Rooted<JSObject*> counts_array(cx, JS_NewArrayObject(cx, count));
+  if (!counts_array
+      || !JS_DefineProperty(cx, obj, "counts", counts_array, JSPROP_ENUMERATE)) {
+    return NS_ERROR_FAILURE;
+  }
+
+  // Fill the "counts" property.
+  for (size_t i = 0; i < count; i++) {
+    if (!JS_DefineElement(cx, counts_array, i, aSnapshot.mBucketCounts[i], JSPROP_ENUMERATE)) {
       return NS_ERROR_FAILURE;
     }
   }

toolkit/components/telemetry/core/nsITelemetry.idl

@@ -56,13 +56,15 @@ interface nsITelemetry : nsISupports
    * The returned structure looks like:
    *   { "process": { "name1": histogramData1, "name2": histogramData2 }, ... }
    *
-   * Each histogram is represented in a packed format and has the following properties:
-   *   bucket_count - Number of buckets of this histogram
+   * Where histogramDataN has the following properties:
+   *   min - minimum bucket size
+   *   max - maximum bucket size
    *   histogram_type - HISTOGRAM_EXPONENTIAL, HISTOGRAM_LINEAR, HISTOGRAM_BOOLEAN,
    *                    HISTOGRAM_FLAG, HISTOGRAM_COUNT, or HISTOGRAM_CATEGORICAL
+   *   counts - array representing contents of the buckets in the histogram
+   *   ranges - array with calculated bucket sizes
    *   sum - sum of the bucket contents
-   *   range - A 2-item array of minimum and maximum bucket size
-   *   values - Map from bucket to the bucket's count
+   * TODO(bug 1468761): Return packed histograms.
    *
    * @param aStoreName The name of the store to snapshot. Ignored at the moment.
    * @param aClearStore Whether to clear out the histograms in the named store after snapshotting.
@@ -106,15 +108,16 @@ interface nsITelemetry : nsISupports
   /**
    * Serializes the histograms from the given dataset to a JSON-style object.
    * The returned structure looks like:
-   *   { "process": { "name1": histogramData1, "name2": histogramData2 }, ... }
+   *   { process1: {name1: {histogramData1}, name2:{histogramData2}...}}
    *
-   * Each histogram is represented in a packed format and has the following properties:
-   *   bucket_count - Number of buckets of this histogram
+   * Where histogramDataN has the following properties:
+   *   min - minimum bucket size
+   *   max - maximum bucket size
    *   histogram_type - HISTOGRAM_EXPONENTIAL, HISTOGRAM_LINEAR, HISTOGRAM_BOOLEAN,
    *                    HISTOGRAM_FLAG, HISTOGRAM_COUNT, or HISTOGRAM_CATEGORICAL
+   *   counts - array representing contents of the buckets in the histogram
+   *   ranges - array with calculated bucket sizes
    *   sum - sum of the bucket contents
-   *   range - A 2-item array of minimum and maximum bucket size
-   *   values - Map from bucket to the bucket's count
    *
    * @param aDataset DATASET_RELEASE_CHANNEL_OPTOUT or DATASET_RELEASE_CHANNEL_OPTIN.
    * @param aClear Whether to clear out the histograms after snapshotting

toolkit/components/telemetry/tests/gtest/TestHistograms.cpp

@@ -166,15 +166,15 @@ TEST_F(TelemetryTestFixture, AccumulateCategoricalHistogram)
   JS::RootedValue histogram(cx.GetJSContext());
   GetProperty(cx.GetJSContext(), "TELEMETRY_TEST_CATEGORICAL", snapshot, &histogram);
 
-  // Get values object from histogram. Each entry in the object maps to a label in the histogram.
-  JS::RootedValue values(cx.GetJSContext());
-  GetProperty(cx.GetJSContext(), "values", histogram,  &values);
+  // Get counts array from histogram. Each entry in the array maps to a label in the histogram.
+  JS::RootedValue counts(cx.GetJSContext());
+  GetProperty(cx.GetJSContext(), "counts", histogram,  &counts);
 
   // Get the value for the label we care about
   JS::RootedValue value(cx.GetJSContext());
   GetElement(cx.GetJSContext(),
              static_cast<uint32_t>(Telemetry::LABELS_TELEMETRY_TEST_CATEGORICAL::CommonLabel),
-             values, &value);
+             counts, &value);
 
   // Check that the value stored in the histogram matches with |kExpectedValue|
   uint32_t uValue = 0;
@@ -213,14 +213,14 @@ TEST_F(TelemetryTestFixture, AccumulateKeyedCategoricalHistogram)
   // Check that the sample histogram contains the values we expect
   JS::RootedValue sample(cx.GetJSContext());
   GetProperty(cx.GetJSContext(), "sample", histogram,  &sample);
-  // Get values object from sample. Each entry in the object maps to a label in the histogram.
-  JS::RootedValue sampleValues(cx.GetJSContext());
-  GetProperty(cx.GetJSContext(), "values", sample,  &sampleValues);
+  // Get counts array from the sample. Each entry in the array maps to a label in the histogram.
+  JS::RootedValue sampleCounts(cx.GetJSContext());
+  GetProperty(cx.GetJSContext(), "counts", sample,  &sampleCounts);
   // Get the value for the label we care about
   JS::RootedValue sampleValue(cx.GetJSContext());
   GetElement(cx.GetJSContext(),
              static_cast<uint32_t>(Telemetry::LABELS_TELEMETRY_TEST_KEYED_CATEGORICAL::CommonLabel),
-             sampleValues, &sampleValue);
+             sampleCounts, &sampleValue);
   // Check that the value stored in the histogram matches with |kSampleExpectedValue|
   uint32_t uSampleValue = 0;
   JS::ToUint32(cx.GetJSContext(), sampleValue, &uSampleValue);
@@ -229,14 +229,14 @@ TEST_F(TelemetryTestFixture, AccumulateKeyedCategoricalHistogram)
   // Check that the other-sample histogram contains the values we expect
   JS::RootedValue otherSample(cx.GetJSContext());
   GetProperty(cx.GetJSContext(), "other-sample", histogram,  &otherSample);
-  // Get values object from the other-sample. Each entry in the object maps to a label in the histogram.
-  JS::RootedValue otherValues(cx.GetJSContext());
-  GetProperty(cx.GetJSContext(), "values", otherSample,  &otherValues);
+  // Get counts array from the other-sample. Each entry in the array maps to a label in the histogram.
+  JS::RootedValue otherCounts(cx.GetJSContext());
+  GetProperty(cx.GetJSContext(), "counts", otherSample,  &otherCounts);
   // Get the value for the label we care about
   JS::RootedValue otherValue(cx.GetJSContext());
   GetElement(cx.GetJSContext(),
              static_cast<uint32_t>(Telemetry::LABELS_TELEMETRY_TEST_KEYED_CATEGORICAL::CommonLabel),
-             otherValues, &otherValue);
+             otherCounts, &otherValue);
   // Check that the value stored in the histogram matches with |kOtherSampleExpectedValue|
   uint32_t uOtherValue = 0;
   JS::ToUint32(cx.GetJSContext(), otherValue, &uOtherValue);
@@ -295,14 +295,14 @@ TEST_F(TelemetryTestFixture, AccumulateLinearHistogram_MultipleSamples)
   JS::RootedValue histogram(cx.GetJSContext());
   GetProperty(cx.GetJSContext(), "TELEMETRY_TEST_LINEAR", snapshot, &histogram);
 
-  // Get "values" object from histogram
-  JS::RootedValue values(cx.GetJSContext());
-  GetProperty(cx.GetJSContext(), "values", histogram, &values);
+  // Get "counts" array from histogram
+  JS::RootedValue counts(cx.GetJSContext());
+  GetProperty(cx.GetJSContext(), "counts", histogram, &counts);
 
   // Index 0 is only for values less than 'low'. Values within range start at index 1
   JS::RootedValue count(cx.GetJSContext());
   const uint32_t index = 1;
-  GetElement(cx.GetJSContext(), index, values, &count);
+  GetElement(cx.GetJSContext(), index, counts, &count);
 
   // Check that this count matches with nSamples
   uint32_t uCount = 0;
@@ -331,20 +331,19 @@ TEST_F(TelemetryTestFixture, AccumulateLinearHistogram_DifferentSamples)
   JS::RootedValue histogram(cx.GetJSContext());
   GetProperty(cx.GetJSContext(), "TELEMETRY_TEST_LINEAR", snapshot, &histogram);
 
-  // Get values object from histogram
-  JS::RootedValue values(cx.GetJSContext());
-  GetProperty(cx.GetJSContext(), "values", histogram, &values);
+  // Get counts array from histogram
+  JS::RootedValue counts(cx.GetJSContext());
+  GetProperty(cx.GetJSContext(), "counts", histogram, &counts);
 
-  // Get values in first and last buckets
+  // Get counts in first and last buckets
   JS::RootedValue countFirst(cx.GetJSContext());
   JS::RootedValue countLast(cx.GetJSContext());
   const uint32_t firstIndex = 1;
-  // Buckets are indexed by their start value
-  const uint32_t lastIndex = INT32_MAX - 1;
-  GetElement(cx.GetJSContext(), firstIndex, values, &countFirst);
-  GetElement(cx.GetJSContext(), lastIndex, values, &countLast);
+  const uint32_t lastIndex = 9;
+  GetElement(cx.GetJSContext(), firstIndex, counts, &countFirst);
+  GetElement(cx.GetJSContext(), lastIndex, counts, &countLast);
 
-  // Check that the values match
+  // Check that the counts match
   uint32_t uCountFirst = 0;
   uint32_t uCountLast = 0;
   JS::ToUint32(cx.GetJSContext(), countFirst, &uCountFirst);
@@ -431,20 +430,19 @@ TEST_F(TelemetryTestFixture, TestKeyedLinearHistogram_MultipleSamples)
   ASSERT_TRUE(!expectedKeyData.isUndefined())
     << "Cannot find the expected key in the histogram data";
 
-  // Get values object from 'testkey' histogram.
-  JS::RootedValue values(cx.GetJSContext());
-  GetProperty(cx.GetJSContext(), "values", expectedKeyData, &values);
+  // Get counts array from 'testkey' histogram.
+  JS::RootedValue counts(cx.GetJSContext());
+  GetProperty(cx.GetJSContext(), "counts", expectedKeyData, &counts);
 
-  // Get values in first and last buckets.
+  // Get counts in first and last buckets.
   JS::RootedValue countFirst(cx.GetJSContext());
   JS::RootedValue countLast(cx.GetJSContext());
   const uint32_t firstIndex = 1;
-  // Buckets are indexed by their start value
-  const uint32_t lastIndex = 250000;
-  GetElement(cx.GetJSContext(), firstIndex, values, &countFirst);
-  GetElement(cx.GetJSContext(), lastIndex, values, &countLast);
+  const uint32_t lastIndex = 9;
+  GetElement(cx.GetJSContext(), firstIndex, counts, &countFirst);
+  GetElement(cx.GetJSContext(), lastIndex, counts, &countLast);
 
-  // Check that the values match.
+  // Check that the counts match.
   uint32_t uCountFirst = 0;
   uint32_t uCountLast = 0;
   JS::ToUint32(cx.GetJSContext(), countFirst, &uCountFirst);
@@ -497,10 +495,10 @@ TEST_F(TelemetryTestFixture, TestKeyedKeysHistogram_MultipleSamples)
   ASSERT_TRUE(!testKeyData.isUndefined())
     << "Cannot find the key 'testkey' in the histogram data";
 
-  JS::RootedValue values(cx.GetJSContext());
-  GetProperty(cx.GetJSContext(), "values", testKeyData,  &values);
+  JS::RootedValue counts(cx.GetJSContext());
+  GetProperty(cx.GetJSContext(), "counts", testKeyData,  &counts);
 
-  // Get values in buckets 0,1,2
+  // Get counts in buckets 0,1,2
   const uint32_t falseIndex = 0;
   const uint32_t trueIndex = 1;
   const uint32_t otherIndex = 2;
@@ -509,9 +507,9 @@ TEST_F(TelemetryTestFixture, TestKeyedKeysHistogram_MultipleSamples)
   JS::RootedValue countTrue(cx.GetJSContext());
   JS::RootedValue countOther(cx.GetJSContext());
 
-  GetElement(cx.GetJSContext(), falseIndex, values, &countFalse);
-  GetElement(cx.GetJSContext(), trueIndex, values, &countTrue);
-  GetElement(cx.GetJSContext(), otherIndex, values, &countOther);
+  GetElement(cx.GetJSContext(), falseIndex, counts, &countFalse);
+  GetElement(cx.GetJSContext(), trueIndex, counts, &countTrue);
+  GetElement(cx.GetJSContext(), otherIndex, counts, &countOther);
 
   uint32_t uCountFalse = 0;
   uint32_t uCountTrue = 0;
@@ -580,15 +578,15 @@ TEST_F(TelemetryTestFixture, AccumulateCategoricalHistogram_MultipleStringLabels
   JS::RootedValue histogram(cx.GetJSContext());
   GetProperty(cx.GetJSContext(), "TELEMETRY_TEST_CATEGORICAL", snapshot, &histogram);
 
-  // Get values object from histogram. Each entry in the object maps to a label in the histogram.
-  JS::RootedValue values(cx.GetJSContext());
-  GetProperty(cx.GetJSContext(), "values", histogram,  &values);
+  // Get counts array from histogram. Each entry in the array maps to a label in the histogram.
+  JS::RootedValue counts(cx.GetJSContext());
+  GetProperty(cx.GetJSContext(), "counts", histogram,  &counts);
 
   // Get the value for the label we care about
   JS::RootedValue value(cx.GetJSContext());
   GetElement(cx.GetJSContext(),
              static_cast<uint32_t>(Telemetry::LABELS_TELEMETRY_TEST_CATEGORICAL::CommonLabel),
-             values, &value);
+             counts, &value);
 
   // Check that the value stored in the histogram matches with |kExpectedValue|
   uint32_t uValue = 0;
@@ -597,7 +595,7 @@ TEST_F(TelemetryTestFixture, AccumulateCategoricalHistogram_MultipleStringLabels
 
   // Now we check for no accumulation when a bad label is present in the array.
   //
-  // The 'values' property is not initialized unless data is accumulated so keeping another test
+  // The 'counts' property is not initialized unless data is accumulated so keeping another test
   // to check for this case alone is wasteful as we will have to accumulate some data anyway.
 
   const nsTArray<nsCString> badLabelArray({
@@ -613,13 +611,13 @@ TEST_F(TelemetryTestFixture, AccumulateCategoricalHistogram_MultipleStringLabels
   // Get our histogram from the snapshot
   GetProperty(cx.GetJSContext(), "TELEMETRY_TEST_CATEGORICAL", snapshot, &histogram);
 
-  // Get values array from histogram
-  GetProperty(cx.GetJSContext(), "values", histogram, &values);
+  // Get counts array from histogram
+  GetProperty(cx.GetJSContext(), "counts", histogram, &counts);
 
   // Get the value for the label we care about
   GetElement(cx.GetJSContext(),
              static_cast<uint32_t>(Telemetry::LABELS_TELEMETRY_TEST_CATEGORICAL::CommonLabel),
-             values, &value);
+             counts, &value);
 
   // Check that the value stored in the histogram matches with |kExpectedValue|
   uValue = 0;
@@ -650,15 +648,15 @@ TEST_F(TelemetryTestFixture, AccumulateCategoricalHistogram_MultipleEnumValues)
   JS::RootedValue histogram(cx.GetJSContext());
   GetProperty(cx.GetJSContext(), "TELEMETRY_TEST_CATEGORICAL", snapshot, &histogram);
 
-  // Get values object from histogram. Each entry in the object maps to a label in the histogram.
-  JS::RootedValue values(cx.GetJSContext());
-  GetProperty(cx.GetJSContext(), "values", histogram,  &values);
+  // Get counts array from histogram. Each entry in the array maps to a label in the histogram.
+  JS::RootedValue counts(cx.GetJSContext());
+  GetProperty(cx.GetJSContext(), "counts", histogram,  &counts);
 
   // Get the value for the label we care about
   JS::RootedValue value(cx.GetJSContext());
   GetElement(cx.GetJSContext(),
              static_cast<uint32_t>(Telemetry::LABELS_TELEMETRY_TEST_CATEGORICAL::CommonLabel),
-             values, &value);
+             counts, &value);
 
   // Check that the value stored in the histogram matches with |kExpectedValue|
   uint32_t uValue = 0;
@@ -695,15 +693,15 @@ TEST_F(TelemetryTestFixture, AccumulateKeyedCategoricalHistogram_MultipleEnumVal
   JS::RootedValue sample(cx.GetJSContext());
   GetProperty(cx.GetJSContext(), "sampleKey", histogram,  &sample);
 
-  // Get values object from the sample. Each entry in the object maps to a label in the histogram.
-  JS::RootedValue sampleKeyValues(cx.GetJSContext());
-  GetProperty(cx.GetJSContext(), "values", sample,  &sampleKeyValues);
+  // Get counts array from the sample. Each entry in the array maps to a label in the histogram.
+  JS::RootedValue sampleKeyCounts(cx.GetJSContext());
+  GetProperty(cx.GetJSContext(), "counts", sample,  &sampleKeyCounts);
 
   // Get the count of CommonLabel
   JS::RootedValue commonLabelValue(cx.GetJSContext());
   GetElement(cx.GetJSContext(),
              static_cast<uint32_t>(Telemetry::LABELS_TELEMETRY_TEST_KEYED_CATEGORICAL::CommonLabel),
-             sampleKeyValues, &commonLabelValue);
+             sampleKeyCounts, &commonLabelValue);
 
   // Check that the value stored in the histogram matches with |kExpectedCommonLabel|
   uint32_t uCommonLabelValue = 0;
@@ -716,7 +714,7 @@ TEST_F(TelemetryTestFixture, AccumulateKeyedCategoricalHistogram_MultipleEnumVal
   JS::RootedValue label2Value(cx.GetJSContext());
   GetElement(cx.GetJSContext(),
              static_cast<uint32_t>(Telemetry::LABELS_TELEMETRY_TEST_KEYED_CATEGORICAL::Label2),
-             sampleKeyValues, &label2Value);
+             sampleKeyCounts, &label2Value);
 
   // Check that the value stored in the histogram matches with |kExpectedLabel2|
   uint32_t uLabel2Value = 0;

toolkit/components/telemetry/tests/unit/head.js

@@ -344,6 +344,10 @@ function setEmptyPrefWatchlist() {
   });
 }
 
+function histogramValueCount(histogramSnapshot) {
+  return histogramSnapshot.counts.reduce((a, b) => a + b);
+}
+
 if (runningInParent) {
   // Set logging preferences for all the tests.
   Services.prefs.setCharPref("toolkit.telemetry.log.level", "Trace");

toolkit/components/telemetry/tests/unit/test_PingAPI.js

@@ -393,7 +393,7 @@ add_task(async function test_archiveCleanup() {
   h = Telemetry.getHistogramById("TELEMETRY_PING_SIZE_EXCEEDED_ARCHIVED").snapshot();
   Assert.equal(h.sum, 1, "Telemetry must report 1 oversized ping in the archive.");
   h = Telemetry.getHistogramById("TELEMETRY_DISCARDED_ARCHIVED_PINGS_SIZE_MB").snapshot();
-  Assert.equal(h.values[archivedPingSizeMB], 1,
+  Assert.equal(h.counts[archivedPingSizeMB], 1,
                "Telemetry must report the correct size for the oversized ping.");
 });
 

toolkit/components/telemetry/tests/unit/test_TelemetryEvents.js

@@ -64,10 +64,10 @@ function checkRegistrationFailure(failureType) {
             "There should be at least one parent histogram when checking for registration failures.");
   Assert.ok("TELEMETRY_EVENT_REGISTRATION_ERROR" in snapshot.parent,
             "TELEMETRY_EVENT_REGISTRATION_ERROR should exist when checking for registration failures.");
-  let values = snapshot.parent.TELEMETRY_EVENT_REGISTRATION_ERROR.values;
-  Assert.ok(!!values,
-            "TELEMETRY_EVENT_REGISTRATION_ERROR's values should exist when checking for registration failures.");
-  Assert.equal(values[failureType], 1, `Event registration ought to have failed due to type ${failureType}`);
+  let counts = snapshot.parent.TELEMETRY_EVENT_REGISTRATION_ERROR.counts;
+  Assert.ok(!!counts,
+            "TELEMETRY_EVENT_REGISTRATION_ERROR's counts should exist when checking for registration failures.");
+  Assert.equal(counts[failureType], 1, `Event registration ought to have failed due to type ${failureType}`);
 }
 
 function checkRecordingFailure(failureType) {
@@ -76,10 +76,10 @@ function checkRecordingFailure(failureType) {
             "There should be at least one parent histogram when checking for recording failures.");
   Assert.ok("TELEMETRY_EVENT_RECORDING_ERROR" in snapshot.parent,
             "TELEMETRY_EVENT_RECORDING_ERROR should exist when checking for recording failures.");
-  let values = snapshot.parent.TELEMETRY_EVENT_RECORDING_ERROR.values;
-  Assert.ok(!!values,
-            "TELEMETRY_EVENT_RECORDING_ERROR's values should exist when checking for recording failures.");
-  Assert.equal(values[failureType], 1, `Event recording ought to have failed due to type ${failureType}`);
+  let counts = snapshot.parent.TELEMETRY_EVENT_RECORDING_ERROR.counts;
+  Assert.ok(!!counts,
+            "TELEMETRY_EVENT_RECORDING_ERROR's counts should exist when checking for recording failures.");
+  Assert.equal(counts[failureType], 1, `Event recording ought to have failed due to type ${failureType}`);
 }
 
 add_task(async function test_event_summary_limit() {

toolkit/components/telemetry/tests/unit/test_TelemetryFlagClear.js

@@ -3,11 +3,11 @@
 
 function run_test() {
   let testFlag = Services.telemetry.getHistogramById("TELEMETRY_TEST_FLAG");
-  deepEqual(testFlag.snapshot().values, {0: 1, 1: 0}, "Original value is correct");
+  equal(JSON.stringify(testFlag.snapshot().counts), "[1,0,0]", "Original value is correct");
   testFlag.add(1);
-  deepEqual(testFlag.snapshot().values, {0: 0, 1: 1, 2: 0}, "Value is correct after ping");
+  equal(JSON.stringify(testFlag.snapshot().counts), "[0,1,0]", "Value is correct after ping.");
   testFlag.clear();
-  deepEqual(testFlag.snapshot().values, {0: 1, 1: 0}, "Value is correct after calling clear()");
+  equal(JSON.stringify(testFlag.snapshot().counts), "[1,0,0]", "Value is correct after calling clear()");
   testFlag.add(1);
-  deepEqual(testFlag.snapshot().values, {0: 0, 1: 1, 2: 0}, "Value is correct after ping");
+  equal(JSON.stringify(testFlag.snapshot().counts), "[0,1,0]", "Value is correct after ping.");
 }

toolkit/components/telemetry/tests/unit/test_TelemetryHistograms.js

@@ -37,35 +37,69 @@ function expect_success(f) {
   Assert.ok(succeeded);
 }
 
+function compareHistograms(h1, h2) {
+  let s1 = h1.snapshot();
+  let s2 = h2.snapshot();
+
+  Assert.equal(s1.histogram_type, s2.histogram_type);
+  Assert.equal(s1.min, s2.min);
+  Assert.equal(s1.max, s2.max);
+  Assert.equal(s1.sum, s2.sum);
+
+  Assert.equal(s1.counts.length, s2.counts.length);
+  for (let i = 0; i < s1.counts.length; i++)
+    Assert.equal(s1.counts[i], s2.counts[i]);
+
+  Assert.equal(s1.ranges.length, s2.ranges.length);
+  for (let i = 0; i < s1.ranges.length; i++)
+    Assert.equal(s1.ranges[i], s2.ranges[i]);
+}
+
 function check_histogram(histogram_type, name, min, max, bucket_count) {
   var h = Telemetry.getHistogramById(name);
-  h.add(0);
+  var r = h.snapshot().ranges;
+  var sum = 0;
+  for (let i = 0;i < r.length;i++) {
+    var v = r[i];
+    sum += v;
+    h.add(v);
+  }
   var s = h.snapshot();
-  Assert.equal(0, s.sum);
+  // verify properties
+  Assert.equal(sum, s.sum);
 
+  // there should be exactly one element per bucket
+  for (let i of s.counts) {
+    Assert.equal(i, 1);
+  }
   var hgrams = Telemetry.snapshotHistograms(Ci.nsITelemetry.DATASET_RELEASE_CHANNEL_OPTIN,
                                             false).parent;
   let gh = hgrams[name];
   Assert.equal(gh.histogram_type, histogram_type);
 
-  Assert.deepEqual(gh.range, [min, max]);
+  Assert.equal(gh.min, min);
+  Assert.equal(gh.max, max);
 
   // Check that booleans work with nonboolean histograms
   h.add(false);
   h.add(true);
-  s = Object.values(h.snapshot().values);
-  Assert.deepEqual(s, [2, 1, 0]);
+  s = h.snapshot().counts;
+  Assert.equal(s[0], 2);
+  Assert.equal(s[1], 2);
 
   // Check that clearing works.
   h.clear();
   s = h.snapshot();
-  Assert.deepEqual(s.values, {});
+  for (var i of s.counts) {
+    Assert.equal(i, 0);
+  }
   Assert.equal(s.sum, 0);
 
   h.add(0);
   h.add(1);
-  var c = Object.values(h.snapshot().values);
-  Assert.deepEqual(c, [1, 1, 0]);
+  var c = h.snapshot().counts;
+  Assert.equal(c[0], 1);
+  Assert.equal(c[1], 1);
 }
 
 // This MUST be the very first test of this file.
@@ -147,43 +181,44 @@ add_task(async function test_noSerialization() {
 
 add_task(async function test_boolean_histogram() {
   var h = Telemetry.getHistogramById("TELEMETRY_TEST_BOOLEAN");
-  var r = h.snapshot().range;
+  var r = h.snapshot().ranges;
   // boolean histograms ignore numeric parameters
-  Assert.deepEqual(r, [1, 2]);
-  h.add(0);
-  h.add(1);
-  h.add(2);
-
+  Assert.equal(uneval(r), uneval([0, 1, 2]));
+  for (var i = 0;i < r.length;i++) {
+    var v = r[i];
+    h.add(v);
+  }
   h.add(true);
   h.add(false);
   var s = h.snapshot();
   Assert.equal(s.histogram_type, Telemetry.HISTOGRAM_BOOLEAN);
   // last bucket should always be 0 since .add parameters are normalized to either 0 or 1
-  Assert.deepEqual(s.values, {0: 2, 1: 3, 2: 0});
+  Assert.equal(s.counts[2], 0);
   Assert.equal(s.sum, 3);
+  Assert.equal(s.counts[0], 2);
 });
 
 add_task(async function test_flag_histogram() {
   var h = Telemetry.getHistogramById("TELEMETRY_TEST_FLAG");
-  var r = h.snapshot().range;
+  var r = h.snapshot().ranges;
   // Flag histograms ignore numeric parameters.
-  Assert.deepEqual(r, [1, 2]);
+  Assert.equal(uneval(r), uneval([0, 1, 2]));
   // Should already have a 0 counted.
-  var v = h.snapshot().values;
+  var c = h.snapshot().counts;
   var s = h.snapshot().sum;
-  Assert.deepEqual(v, {0: 1, 1: 0});
+  Assert.equal(uneval(c), uneval([1, 0, 0]));
   Assert.equal(s, 0);
   // Should switch counts.
   h.add(1);
-  var v2 = h.snapshot().values;
+  var c2 = h.snapshot().counts;
   var s2 = h.snapshot().sum;
-  Assert.deepEqual(v2, {0: 0, 1: 1, 2: 0});
+  Assert.equal(uneval(c2), uneval([0, 1, 0]));
   Assert.equal(s2, 1);
   // Should only switch counts once.
   h.add(1);
-  var v3 = h.snapshot().values;
+  var c3 = h.snapshot().counts;
   var s3 = h.snapshot().sum;
-  Assert.deepEqual(v3, {0: 0, 1: 1, 2: 0});
+  Assert.equal(uneval(c3), uneval([0, 1, 0]));
   Assert.equal(s3, 1);
   Assert.equal(h.snapshot().histogram_type, Telemetry.HISTOGRAM_FLAG);
 });
@@ -191,16 +226,16 @@ add_task(async function test_flag_histogram() {
 add_task(async function test_count_histogram() {
   let h = Telemetry.getHistogramById("TELEMETRY_TEST_COUNT2");
   let s = h.snapshot();
-  Assert.deepEqual(s.range, [1, 2]);
-  Assert.deepEqual(s.values, {});
+  Assert.equal(uneval(s.ranges), uneval([0, 1, 2]));
+  Assert.equal(uneval(s.counts), uneval([0, 0, 0]));
   Assert.equal(s.sum, 0);
   h.add();
   s = h.snapshot();
-  Assert.deepEqual(s.values, {0: 1, 1: 0});
+  Assert.equal(uneval(s.counts), uneval([1, 0, 0]));
   Assert.equal(s.sum, 1);
   h.add();
   s = h.snapshot();
-  Assert.deepEqual(s.values, {0: 2, 1: 0});
+  Assert.equal(uneval(s.counts), uneval([2, 0, 0]));
   Assert.equal(s.sum, 2);
 });
 
@@ -215,10 +250,16 @@ add_task(async function test_categorical_histogram() {
     h1.add(s);
   }
 
+  // Categorical histograms default to 50 linear buckets.
+  let expectedRanges = [];
+  for (let i = 0; i < 51; ++i) {
+    expectedRanges.push(i);
+  }
+
   let snapshot = h1.snapshot();
   Assert.equal(snapshot.sum, 6);
-  Assert.deepEqual(snapshot.range, [1, 50]);
-  Assert.deepEqual(snapshot.values, {0: 3, 1: 2, 2: 2, 3: 0});
+  Assert.deepEqual(snapshot.ranges, expectedRanges);
+  Assert.deepEqual(snapshot.counts.slice(0, 4), [3, 2, 2, 0]);
 
   let h2 = Telemetry.getHistogramById("TELEMETRY_TEST_CATEGORICAL_OPTOUT");
   for (let v of ["CommonLabel", "CommonLabel", "Label4", "Label5", "Label6", 0, 1]) {
@@ -232,8 +273,8 @@ add_task(async function test_categorical_histogram() {
 
   snapshot = h2.snapshot();
   Assert.equal(snapshot.sum, 7);
-  Assert.deepEqual(snapshot.range, [1, 50]);
-  Assert.deepEqual(snapshot.values, {0: 3, 1: 2, 2: 1, 3: 1, 4: 0});
+  Assert.deepEqual(snapshot.ranges, expectedRanges);
+  Assert.deepEqual(snapshot.counts.slice(0, 5), [3, 2, 1, 1, 0]);
 
   // This histogram overrides the default of 50 values to 70.
   let h3 = Telemetry.getHistogramById("TELEMETRY_TEST_CATEGORICAL_NVALUES");
@@ -241,10 +282,16 @@ add_task(async function test_categorical_histogram() {
     h3.add(v);
   }
 
+  expectedRanges = [];
+  for (let i = 0; i < 71; ++i) {
+    expectedRanges.push(i);
+  }
+
   snapshot = h3.snapshot();
   Assert.equal(snapshot.sum, 3);
-  Assert.deepEqual(snapshot.range, [1, 70]);
-  Assert.deepEqual(snapshot.values, {0: 1, 1: 1, 2: 1, 3: 0});
+  Assert.equal(snapshot.ranges.length, expectedRanges.length);
+  Assert.deepEqual(snapshot.ranges, expectedRanges);
+  Assert.deepEqual(snapshot.counts.slice(0, 4), [1, 1, 1, 0]);
 });
 
 add_task(async function test_add_error_behaviour() {
@@ -306,7 +353,8 @@ add_task(async function test_getHistogramById() {
   var h = Telemetry.getHistogramById("CYCLE_COLLECTOR");
   var s = h.snapshot();
   Assert.equal(s.histogram_type, Telemetry.HISTOGRAM_EXPONENTIAL);
-  Assert.deepEqual(s.range, [1, 10000]);
+  Assert.equal(s.min, 1);
+  Assert.equal(s.max, 10000);
 });
 
 add_task(async function test_getSlowSQL() {
@@ -327,10 +375,10 @@ add_task(async function test_privateMode() {
   var orig = h.snapshot();
   Telemetry.canRecordExtended = false;
   h.add(1);
-  Assert.deepEqual(orig, h.snapshot());
+  Assert.equal(uneval(orig), uneval(h.snapshot()));
   Telemetry.canRecordExtended = true;
   h.add(1);
-  Assert.notDeepEqual(orig, h.snapshot());
+  Assert.notEqual(uneval(orig), uneval(h.snapshot()));
 });
 
 // Check that telemetry records only when it is suppose to.
@@ -442,11 +490,12 @@ add_task(async function test_keyed_boolean_histogram() {
   let KEYS = numberRange(0, 2).map(i => "key" + (i + 1));
   KEYS.push("漢語");
   let histogramBase = {
-    "range": [1, 2],
-    "bucket_count": 3,
+    "min": 1,
+    "max": 2,
     "histogram_type": 2,
     "sum": 1,
-    "values": {0: 0, 1: 1, 2: 0},
+    "ranges": [0, 1, 2],
+    "counts": [0, 1, 0],
   };
   let testHistograms = numberRange(0, 3).map(i => JSON.parse(JSON.stringify(histogramBase)));
   let testKeys = [];
@@ -472,7 +521,7 @@ add_task(async function test_keyed_boolean_histogram() {
   testKeys.push(key);
   testSnapShot[key] = testHistograms[2];
   testSnapShot[key].sum = 0;
-  testSnapShot[key].values = {0: 1, 1: 0};
+  testSnapShot[key].counts = [1, 0, 0];
   Assert.deepEqual(h.keys().sort(), testKeys);
   Assert.deepEqual(h.snapshot(), testSnapShot);
 
@@ -489,11 +538,12 @@ add_task(async function test_keyed_count_histogram() {
   const KEYED_ID = "TELEMETRY_TEST_KEYED_COUNT";
   const KEYS = numberRange(0, 5).map(i => "key" + (i + 1));
   let histogramBase = {
-    "range": [1, 2],
-    "bucket_count": 3,
+    "min": 1,
+    "max": 2,
     "histogram_type": 4,
     "sum": 0,
-    "values": {0: 1, 1: 0},
+    "ranges": [0, 1, 2],
+    "counts": [1, 0, 0],
   };
   let testHistograms = numberRange(0, 5).map(i => JSON.parse(JSON.stringify(histogramBase)));
   let testKeys = [];
@@ -508,7 +558,7 @@ add_task(async function test_keyed_count_histogram() {
     for (let k = 0; k < value; ++k) {
       h.add(key);
     }
-    testHistograms[i].values[0] = value;
+    testHistograms[i].counts[0] = value;
     testHistograms[i].sum = value;
     testSnapShot[key] = testHistograms[i];
     testKeys.push(key);
@@ -525,7 +575,7 @@ add_task(async function test_keyed_count_histogram() {
   let key = KEYS[4];
   h.add(key);
   testKeys.push(key);
-  testHistograms[4].values[0] = 1;
+  testHistograms[4].counts[0] = 1;
   testHistograms[4].sum = 1;
   testSnapShot[key] = testHistograms[4];
 
@@ -565,6 +615,12 @@ add_task(async function test_keyed_categorical_histogram() {
     }
   }
 
+  // Categorical histograms default to 50 linear buckets.
+  let expectedRanges = [];
+  for (let i = 0; i < 51; ++i) {
+    expectedRanges.push(i);
+  }
+
   // Check that the set of keys in the snapshot is what we expect.
   let snapshot = h.snapshot();
   let snapshotKeys = Object.keys(snapshot);
@@ -575,8 +631,8 @@ add_task(async function test_keyed_categorical_histogram() {
   for (let k of KEYS) {
     Assert.ok(k in snapshot);
     Assert.equal(snapshot[k].sum, 6);
-    Assert.deepEqual(snapshot[k].range, [1, 50]);
-    Assert.deepEqual(snapshot[k].values, {0: 3, 1: 2, 2: 2, 3: 0});
+    Assert.deepEqual(snapshot[k].ranges, expectedRanges);
+    Assert.deepEqual(snapshot[k].counts.slice(0, 4), [3, 2, 2, 0]);
   }
 });
 
@@ -589,11 +645,12 @@ add_task(async function test_keyed_flag_histogram() {
 
   let testSnapshot = {};
   testSnapshot[KEY] = {
-    "range": [1, 2],
-    "bucket_count": 3,
+    "min": 1,
+    "max": 2,
     "histogram_type": 3,
     "sum": 1,
-    "values": {0: 0, 1: 1, 2: 0},
+    "ranges": [0, 1, 2],
+    "counts": [0, 1, 0],
   };
 
   Assert.deepEqual(h.keys().sort(), [KEY]);
@@ -803,9 +860,9 @@ add_task(async function test_keyed_keys() {
   Assert.equal(Object.keys(snap).length, 2, "Only 2 keys must be recorded.");
   Assert.ok("testkey" in snap, "'testkey' must be recorded.");
   Assert.ok("thirdKey" in snap, "'thirdKey' must be recorded.");
-  Assert.deepEqual(snap.testkey.values, {0: 0, 1: 1, 2: 0},
+  Assert.deepEqual(snap.testkey.counts, [0, 1, 0],
                    "'testkey' must contain the correct value.");
-  Assert.deepEqual(snap.thirdKey.values, {0: 1, 1: 0},
+  Assert.deepEqual(snap.thirdKey.counts, [1, 0, 0],
                    "'thirdKey' must contain the correct value.");
 
   // Keys that are not allowed must not be recorded.
@@ -837,11 +894,11 @@ add_task(async function test_count_multiple_samples() {
   Assert.equal(s1.sum, 0);
   // Ensure that no accumulations of 0-like values took place.
   // These accumulations won't increase the sum.
-  Assert.deepEqual({}, s1.values);
+  Assert.equal(s1.counts.reduce((acc, cur) => acc + cur), 0);
 
   h.add(valid);
   let s2 = h.snapshot();
-  Assert.deepEqual(s2.values, {0: 4, 1: 0});
+  Assert.equal(uneval(s2.counts), uneval([4, 0, 0]));
   Assert.equal(s2.sum, 5);
 });
 
@@ -856,12 +913,12 @@ add_task(async function test_categorical_multiple_samples() {
   h.add(valid.concat(invalid));
   let s1 = h.snapshot();
   Assert.equal(s1.sum, 0);
-  Assert.deepEqual({}, s1.values);
+  Assert.equal(s1.counts.reduce((acc, cur) => acc + cur), 0);
 
   h.add(valid);
   let snapshot = h.snapshot();
   Assert.equal(snapshot.sum, 6);
-  Assert.deepEqual(snapshot.values, {0: 3, 1: 2, 2: 2, 3: 0});
+  Assert.deepEqual(snapshot.counts.slice(0, 4), [3, 2, 2, 0]);
 });
 
 add_task(async function test_boolean_multiple_samples() {
@@ -876,11 +933,11 @@ add_task(async function test_boolean_multiple_samples() {
   h.add(valid.concat(invalid));
   let s1 = h.snapshot();
   Assert.equal(s1.sum, 0);
-  Assert.deepEqual({}, s1.values);
+  Assert.equal(s1.counts.reduce((acc, cur) => acc + cur), 0);
 
   h.add(valid);
   let s = h.snapshot();
-  Assert.deepEqual(s.values, {0: 2, 1: 3, 2: 0});
+  Assert.deepEqual(s.counts, [2, 3, 0]);
   Assert.equal(s.sum, 3);
 });
 
@@ -898,13 +955,14 @@ add_task(async function test_linear_multiple_samples() {
    h.add(valid.concat(invalid));
    let s1 = h.snapshot();
    Assert.equal(s1.sum, 0);
-   Assert.deepEqual({}, s1.values);
+   Assert.equal(s1.counts.reduce((acc, cur) => acc + cur), 0);
 
   h.add(valid);
   let s2 = h.snapshot();
   // Values >= INT32_MAX are accumulated as INT32_MAX - 1
   Assert.equal(s2.sum, valid.reduce((acc, cur) => acc + cur) - 3);
-  Assert.deepEqual(Object.values(s2.values), [1, 3, 2, 1]);
+  Assert.equal(s2.counts[9], 1);
+  Assert.deepEqual(s2.counts.slice(0, 3), [1, 3, 2]);
 });
 
 add_task(async function test_keyed_no_arguments() {
@@ -946,11 +1004,11 @@ add_task(async function test_keyed_count_multiple_samples() {
   Assert.equal(s1.sum, 0);
   // Ensure that no accumulations of 0-like values took place.
   // These accumulations won't increase the sum.
-  Assert.deepEqual({}, s1.values);
+  Assert.equal(s1.counts.reduce((acc, cur) => acc + cur), 0);
 
   h.add(key, valid);
   let s2 = h.snapshot(key);
-  Assert.deepEqual(s2.values, {0: 4, 1: 0});
+  Assert.equal(uneval(s2.counts), uneval([4, 0, 0]));
   Assert.equal(s2.sum, 5);
 });
 
@@ -966,12 +1024,12 @@ add_task(async function test_keyed_categorical_multiple_samples() {
   h.add(key, valid.concat(invalid));
   let s1 = h.snapshot(key);
   Assert.equal(s1.sum, 0);
-  Assert.deepEqual({}, s1.values);
+  Assert.equal(s1.counts.reduce((acc, cur) => acc + cur), 0);
 
   h.add(key, valid);
   let snapshot = h.snapshot(key);
   Assert.equal(snapshot.sum, 6);
-  Assert.deepEqual(Object.values(snapshot.values), [3, 2, 2, 0]);
+  Assert.deepEqual(snapshot.counts.slice(0, 4), [3, 2, 2, 0]);
 });
 
 add_task(async function test_keyed_boolean_multiple_samples() {
@@ -987,11 +1045,11 @@ add_task(async function test_keyed_boolean_multiple_samples() {
   h.add(key, valid.concat(invalid));
   let s1 = h.snapshot(key);
   Assert.equal(s1.sum, 0);
-  Assert.deepEqual({}, s1.values);
+  Assert.equal(s1.counts.reduce((acc, cur) => acc + cur), 0);
 
   h.add(key, valid);
   let s = h.snapshot(key);
-  Assert.deepEqual(s.values, {0: 2, 1: 3, 2: 0});
+  Assert.deepEqual(s.counts, [2, 3, 0]);
   Assert.equal(s.sum, 3);
 });
 
@@ -1010,14 +1068,14 @@ add_task(async function test_keyed_linear_multiple_samples() {
    h.add(key, valid.concat(invalid));
    let s1 = h.snapshot(key);
    Assert.equal(s1.sum, 0);
-   Assert.deepEqual({}, s1.values);
+   Assert.equal(s1.counts.reduce((acc, cur) => acc + cur), 0);
 
   h.add(key, valid);
   let s2 = h.snapshot(key);
   // Values >= INT32_MAX are accumulated as INT32_MAX - 1
   Assert.equal(s2.sum, valid.reduce((acc, cur) => acc + cur) - 3);
-  Assert.deepEqual(s2.range, [1, 250000]);
-  Assert.deepEqual(s2.values, {0: 1, 1: 3, 250000: 3});
+  Assert.equal(s2.counts[9], 3);
+  Assert.deepEqual(s2.counts.slice(0, 3), [1, 3, 0]);
 });
 
 add_task(async function test_non_array_non_string_obj() {

toolkit/components/telemetry/tests/unit/test_TelemetrySend.js

@@ -78,7 +78,7 @@ var checkPingsSaved = async function(pingIds) {
 };
 
 function histogramValueCount(h) {
-  return Object.values(h.values).reduce((a, b) => a + b, 0);
+  return h.counts.reduce((a, b) => a + b);
 }
 
 add_task(async function test_setup() {
@@ -135,7 +135,7 @@ add_task(async function test_sendPendingPings() {
   Assert.equal(TelemetrySend.pendingPingCount, TYPE_A_COUNT + TYPE_B_COUNT,
                "Should have correct pending ping count");
 
-  Assert.deepEqual(histSuccess.snapshot().values, {},
+  Assert.deepEqual(histSuccess.snapshot().counts, [0, 0, 0],
                "Should not have recorded any sending in histograms yet.");
   Assert.equal(histSendTimeSuccess.snapshot().sum, 0,
                "Should not have recorded any sending in histograms yet.");
@@ -166,7 +166,7 @@ add_task(async function test_sendPendingPings() {
   Assert.equal(countByType.get(TEST_TYPE_A), 10 - TYPE_B_COUNT,
                "Should have received the correct amount of type A pings");
 
-  Assert.deepEqual(histSuccess.snapshot().values, {0: 0, 1: 10, 2: 0},
+  Assert.deepEqual(histSuccess.snapshot().counts, [0, 10, 0],
                "Should have recorded sending success in histograms.");
   Assert.equal(histogramValueCount(histSendTimeSuccess.snapshot()), 10,
                "Should have recorded successful send times in histograms.");
@@ -272,7 +272,7 @@ add_task(async function test_backoffTimeout() {
   Assert.equal(pingSendTimeout, MAX_BACKOFF_TIMEOUT, "Tick timeout should be capped");
   ++sendAttempts;
 
-  Assert.deepEqual(histSuccess.snapshot().values, {0: sendAttempts, 1: 0},
+  Assert.deepEqual(histSuccess.snapshot().counts, [sendAttempts, 0, 0],
                "Should have recorded sending failure in histograms.");
   Assert.equal(histSendTimeSuccess.snapshot().sum, 0,
                "Should not have recorded any sending success in histograms yet.");
@@ -309,7 +309,7 @@ add_task(async function test_backoffTimeout() {
   await TelemetrySend.testWaitOnOutgoingPings();
   Assert.equal(TelemetrySend.pendingPingCount, 0, "Should have no pending pings left");
 
-  Assert.deepEqual(histSuccess.snapshot().values, {0: sendAttempts, 1: 3, 2: 0},
+  Assert.deepEqual(histSuccess.snapshot().counts, [sendAttempts, 3, 0],
                "Should have recorded sending failure in histograms.");
   Assert.greaterOrEqual(histSendTimeSuccess.snapshot().sum, 0,
                         "Should have recorded sending success in histograms.");
@@ -341,7 +341,7 @@ add_task(async function test_discardBigPings() {
 
   Assert.equal(histSizeExceeded.snapshot().sum, 0, "Telemetry must report no oversized ping submitted.");
   Assert.equal(histDiscardedSize.snapshot().sum, 0, "Telemetry must report no oversized pings.");
-  Assert.deepEqual(histSuccess.snapshot().values, {0: 0, 1: 1, 2: 0}, "Should have recorded sending success.");
+  Assert.deepEqual(histSuccess.snapshot().counts, [0, 1, 0], "Should have recorded sending success.");
   Assert.equal(histogramValueCount(histSendTimeSuccess.snapshot()), 1, "Should have recorded send success time.");
   Assert.greaterOrEqual(histSendTimeSuccess.snapshot().sum, 0, "Should have recorded send success time.");
   Assert.equal(histogramValueCount(histSendTimeFail.snapshot()), 0, "Should not have recorded send failure time.");
@@ -362,9 +362,9 @@ add_task(async function test_discardBigPings() {
   Assert.deepEqual(ping.payload.os, TelemetryHealthPing.OsInfo, "Should have correct os info.");
 
   Assert.equal(histSizeExceeded.snapshot().sum, 1, "Telemetry must report 1 oversized ping submitted.");
-  Assert.equal(histDiscardedSize.snapshot().values[2], 1, "Telemetry must report a 2MB, oversized, ping submitted.");
+  Assert.equal(histDiscardedSize.snapshot().counts[2], 1, "Telemetry must report a 2MB, oversized, ping submitted.");
 
-  Assert.deepEqual(histSuccess.snapshot().values, {0: 0, 1: 2, 2: 0}, "Should have recorded sending success.");
+  Assert.deepEqual(histSuccess.snapshot().counts, [0, 2, 0], "Should have recorded sending success.");
   Assert.equal(histogramValueCount(histSendTimeSuccess.snapshot()), 2, "Should have recorded send success time.");
   Assert.greaterOrEqual(histSendTimeSuccess.snapshot().sum, 0, "Should have recorded send success time.");
   Assert.equal(histogramValueCount(histSendTimeFail.snapshot()), 0, "Should not have recorded send failure time.");
@@ -384,7 +384,7 @@ add_task(async function test_largeButWithinLimit() {
   await TelemetrySend.testWaitOnOutgoingPings();
   await PingServer.promiseNextRequest();
 
-  Assert.deepEqual(histSuccess.snapshot().values, {0: 0, 1: 1, 2: 0}, "Should have sent large ping.");
+  Assert.deepEqual(histSuccess.snapshot().counts, [0, 1, 0], "Should have sent large ping.");
 });
 
 add_task(async function test_evictedOnServerErrors() {
@@ -414,7 +414,7 @@ add_task(async function test_evictedOnServerErrors() {
 
   Assert.equal(histEvicted.snapshot().sum, 1,
                "Telemetry must report a ping evicted due to server errors");
-  Assert.deepEqual(histSuccess.snapshot().values, {0: 0, 1: 1, 2: 0});
+  Assert.deepEqual(histSuccess.snapshot().counts, [0, 1, 0]);
   Assert.equal(histogramValueCount(histSendTimeSuccess.snapshot()), 1);
   Assert.greaterOrEqual(histSendTimeSuccess.snapshot().sum, 0);
   Assert.equal(histogramValueCount(histSendTimeFail.snapshot()), 0);
@@ -434,7 +434,7 @@ add_task(async function test_evictedOnServerErrors() {
   // We should not have updated the error histogram.
   await TelemetrySend.testWaitOnOutgoingPings();
   Assert.equal(histEvicted.snapshot().sum, 1, "Telemetry must report only one ping evicted due to server errors");
-  Assert.deepEqual(histSuccess.snapshot().values, {0: 0, 1: 2, 2: 0});
+  Assert.deepEqual(histSuccess.snapshot().counts, [0, 2, 0]);
   Assert.equal(histogramValueCount(histSendTimeSuccess.snapshot()), 2);
   Assert.equal(histogramValueCount(histSendTimeFail.snapshot()), 0);
 });
@@ -459,7 +459,7 @@ add_task(async function test_tooLateToSend() {
   Assert.equal(pendingPings.length, 1, "Should have a pending ping in storage");
   Assert.equal(pendingPings[0].id, id, "Should have pended our test's ping");
 
-  Assert.equal(Telemetry.getHistogramById("TELEMETRY_SEND_FAILURE_TYPE").snapshot().values[7], 1,
+  Assert.equal(Telemetry.getHistogramById("TELEMETRY_SEND_FAILURE_TYPE").snapshot().counts[7], 1,
     "Should have registered the failed attempt to send");
 
   await TelemetryStorage.reset();

toolkit/components/telemetry/tests/unit/test_TelemetrySendOldPings.js

@@ -479,7 +479,7 @@ add_task(async function test_pendingPingsQuota() {
   h = Telemetry.getHistogramById("TELEMETRY_PING_SIZE_EXCEEDED_PENDING").snapshot();
   Assert.equal(h.sum, 1, "Telemetry must report 1 oversized ping in the pending pings directory.");
   h = Telemetry.getHistogramById("TELEMETRY_DISCARDED_PENDING_PINGS_SIZE_MB").snapshot();
-  Assert.equal(h.values[2], 1, "Telemetry must report a 2MB, oversized, ping.");
+  Assert.equal(h.counts[2], 1, "Telemetry must report a 2MB, oversized, ping.");
 
   // Save the ping again to check if it gets pruned when scanning the pings directory.
   await TelemetryStorage.savePendingPing(OVERSIZED_PING);
@@ -494,7 +494,7 @@ add_task(async function test_pendingPingsQuota() {
   h = Telemetry.getHistogramById("TELEMETRY_PING_SIZE_EXCEEDED_PENDING").snapshot();
   Assert.equal(h.sum, 2, "Telemetry must report 1 oversized ping in the pending pings directory.");
   h = Telemetry.getHistogramById("TELEMETRY_DISCARDED_PENDING_PINGS_SIZE_MB").snapshot();
-  Assert.equal(h.values[2], 2, "Telemetry must report two 2MB, oversized, pings.");
+  Assert.equal(h.counts[2], 2, "Telemetry must report two 2MB, oversized, pings.");
 
   Services.prefs.setBoolPref(TelemetryUtils.Preferences.FhrUploadEnabled, true);
 });

toolkit/components/telemetry/tests/unit/test_TelemetrySession.js

@@ -330,7 +330,7 @@ function checkPayload(payload, reason, successfulPings) {
     sum: 0,
   };
   let flag = payload.histograms[TELEMETRY_TEST_FLAG];
-  Assert.deepEqual(flag, expected_flag);
+  Assert.equal(uneval(flag), uneval(expected_flag));
 
   // We should have a test count.
   const expected_count = {
@@ -341,7 +341,7 @@ function checkPayload(payload, reason, successfulPings) {
     sum: 1,
   };
   let count = payload.histograms[TELEMETRY_TEST_COUNT];
-  Assert.deepEqual(count, expected_count);
+  Assert.equal(uneval(count), uneval(expected_count));
 
   // There should be one successful report from the previous telemetry ping.
   if (successfulPings > 0) {
@@ -353,7 +353,7 @@ function checkPayload(payload, reason, successfulPings) {
       sum: successfulPings,
     };
     let tc = payload.histograms[TELEMETRY_SUCCESS];
-    Assert.deepEqual(tc, expected_tc);
+    Assert.equal(uneval(tc), uneval(expected_tc));
   }
 
   // The ping should include data from memory reporters.  We can't check that

toolkit/components/telemetry/tests/unit/test_TelemetryStopwatch.js

@@ -16,15 +16,15 @@ var originalCount1, originalCount2, originalCount3;
 function run_test() {
   let histogram = Telemetry.getHistogramById(HIST_NAME);
   let snapshot = histogram.snapshot();
-  originalCount1 = Object.values(snapshot.values).reduce((a, b) => a += b, 0);
+  originalCount1 = snapshot.counts.reduce((a, b) => a += b);
 
   histogram = Telemetry.getHistogramById(HIST_NAME2);
   snapshot = histogram.snapshot();
-  originalCount2 = Object.values(snapshot.values).reduce((a, b) => a += b, 0);
+  originalCount2 = snapshot.counts.reduce((a, b) => a += b);
 
   histogram = Telemetry.getKeyedHistogramById(KEYED_HIST.id);
   snapshot = histogram.snapshot(KEYED_HIST.key);
-  originalCount3 = Object.values(snapshot.values).reduce((a, b) => a += b, 0);
+  originalCount3 = snapshot.counts.reduce((a, b) => a += b);
 
   Assert.ok(!TelemetryStopwatch.start(3));
   Assert.ok(!TelemetryStopwatch.start({}));
@@ -177,19 +177,19 @@ function run_test() {
 function finishTest() {
   let histogram = Telemetry.getHistogramById(HIST_NAME);
   let snapshot = histogram.snapshot();
-  let newCount = Object.values(snapshot.values).reduce((a, b) => a += b, 0);
+  let newCount = snapshot.counts.reduce((a, b) => a += b);
 
   Assert.equal(newCount - originalCount1, 5, "The correct number of histograms were added for histogram 1.");
 
   histogram = Telemetry.getHistogramById(HIST_NAME2);
   snapshot = histogram.snapshot();
-  newCount = Object.values(snapshot.values).reduce((a, b) => a += b, 0);
+  newCount = snapshot.counts.reduce((a, b) => a += b);
 
   Assert.equal(newCount - originalCount2, 3, "The correct number of histograms were added for histogram 2.");
 
   histogram = Telemetry.getKeyedHistogramById(KEYED_HIST.id);
   snapshot = histogram.snapshot(KEYED_HIST.key);
-  newCount = Object.values(snapshot.values).reduce((a, b) => a += b, 0);
+  newCount = snapshot.counts.reduce((a, b) => a += b);
 
   Assert.equal(newCount - originalCount3, 2, "The correct number of histograms were added for histogram 3.");
 }

toolkit/components/telemetry/tests/unit/test_TelemetryUtils.js

@@ -10,24 +10,28 @@ add_task(async function testHistogramPacking() {
   const HISTOGRAM_SNAPSHOT = {
     sample_process: {
       HISTOGRAM_1_DATA: {
-        range: [1, 2],
-        bucket_count: 3,
-        histogram_type: 4,
-        values: {
-          "0": 1,
-          "1": 0,
-        },
+        counts: [
+          1, 0, 0,
+        ],
+        ranges: [
+          0, 1, 2,
+        ],
+        max: 2,
+        min: 1,
         sum: 1,
+        histogram_type: 4,
       },
       TELEMETRY_TEST_HISTOGRAM_2_DATA: {
-        range: [1, 2],
-        bucket_count: 3,
-        histogram_type: 4,
-        values: {
-          "0": 1,
-          "1": 0,
-        },
+        counts: [
+          1, 0, 0,
+        ],
+        ranges: [
+          0, 1, 2,
+        ],
+        max: 2,
+        min: 1,
         sum: 1,
+        histogram_type: 4,
       },
     },
   };
@@ -79,36 +83,42 @@ add_task(async function testKeyedHistogramPacking() {
     sample_process: {
       HISTOGRAM_1_DATA: {
         someKey: {
-          range: [1, 2],
-          bucket_count: 3,
-          histogram_type: 4,
-          values: {
-            "0": 1,
-            "1": 0,
-          },
+          counts: [
+            1, 0, 0,
+          ],
+          ranges: [
+            0, 1, 2,
+          ],
+          max: 2,
+          min: 1,
           sum: 1,
+          histogram_type: 4,
         },
         otherKey: {
-          range: [1, 2],
-          bucket_count: 3,
-          histogram_type: 4,
-          values: {
-            "0": 1,
-            "1": 0,
-          },
+          counts: [
+            1, 0, 0,
+          ],
+          ranges: [
+            0, 1, 2,
+          ],
+          max: 2,
+          min: 1,
           sum: 1,
+          histogram_type: 4,
         },
       },
       TELEMETRY_TEST_HISTOGRAM_2_DATA: {
         someKey: {
-          range: [1, 2],
-          bucket_count: 3,
-          histogram_type: 4,
-          values: {
-            "0": 1,
-            "1": 0,
-          },
+          counts: [
+            1, 0, 0,
+          ],
+          ranges: [
+            0, 1, 2,
+          ],
+          max: 2,
+          min: 1,
           sum: 1,
+          histogram_type: 4,
         },
       },
     },