1 files changed, 115 insertions, 0 deletions
diff --git a/devtools/client/aboutdebugging/test/browser/helper-telemetry.js b/devtools/client/aboutdebugging/test/browser/helper-telemetry.js
new file mode 100644
index 0000000000..228f01aff3
--- /dev/null
+++ b/devtools/client/aboutdebugging/test/browser/helper-telemetry.js
@@ -0,0 +1,115 @@
+/* Any copyright is dedicated to the Public Domain.
+   http://creativecommons.org/publicdomain/zero/1.0/ */
+
+"use strict";
+
+/* import-globals-from head.js */
+
+/**
+ * Reset all telemetry events.
+ */
+function setupTelemetryTest() {
+  // Let's reset the counts.
+  Services.telemetry.clearEvents();
+
+  // Ensure no events have been logged
+  const ALL_CHANNELS = Ci.nsITelemetry.DATASET_ALL_CHANNELS;
+  const snapshot = Services.telemetry.snapshotEvents(ALL_CHANNELS, true);
+  ok(!snapshot.parent, "No events have been logged for the main process");
+}
+/* exported setupTelemetryTest */
+
+/**
+ * Check that the logged telemetry events exactly match the array of expected events.
+ * Will compare the number of events, the event methods, and the event extras including
+ * the about:debugging session id.
+ */
+function checkTelemetryEvents(expectedEvents, expectedSessionId) {
+  const evts = readAboutDebuggingEvents();
+  is(evts.length, expectedEvents.length, "Expected number of events");
+
+  function _eventHasExpectedExtras(e, expectedEvent) {
+    const expectedExtras = Object.keys(expectedEvent.extras);
+    return expectedExtras.every(extra => {
+      return e.extras[extra] === expectedEvent.extras[extra];
+    });
+  }
+
+  for (const expectedEvent of expectedEvents) {
+    const sameMethodEvents = evts.filter(
+      e => e.method === expectedEvent.method
+    );
+    ok(
+      !!sameMethodEvents.length,
+      "Found event for method: " + expectedEvent.method
+    );
+
+    const sameExtrasEvents = sameMethodEvents.filter(e =>
+      _eventHasExpectedExtras(e, expectedEvent)
+    );
+    ok(
+      sameExtrasEvents.length === 1,
+      "Found exactly one event matching the expected extras"
+    );
+    if (sameExtrasEvents.length === 0) {
+      info(JSON.stringify(sameMethodEvents));
+    }
+    is(
+      sameExtrasEvents[0].extras.session_id,
+      expectedSessionId,
+      "Select page event has the expected session"
+    );
+  }
+
+  return evts;
+}
+/* exported checkTelemetryEvents */
+
+/**
+ * Retrieve the session id from an "open" event.
+ * Note that calling this will "clear" all the events.
+ */
+function getOpenEventSessionId() {
+  const openEvents = readAboutDebuggingEvents().filter(
+    e => e.method === "open_adbg"
+  );
+  ok(!!openEvents[0], "Found an about:debugging open event");
+  return openEvents[0].extras.session_id;
+}
+/* exported getOpenEventSessionId */
+
+/**
+ * Read all the pending events that have "aboutdebugging" as their object property.
+ * WARNING: Calling this method also flushes/clears the events.
+ */
+function readAboutDebuggingEvents() {
+  const ALL_CHANNELS = Ci.nsITelemetry.DATASET_ALL_CHANNELS;
+  // Retrieve and clear telemetry events.
+  const snapshot = Services.telemetry.snapshotEvents(ALL_CHANNELS, true);
+  // about:debugging events are logged in the parent process
+  const parentEvents = snapshot.parent || [];
+
+  return parentEvents
+    .map(_toEventObject)
+    .filter(e => e.object === "aboutdebugging");
+}
+/* exported getLoggedEvents */
+
+/**
+ * The telemetry event data structure is simply an array. This helper remaps the array to
+ * an object with more user friendly properties.
+ */
+function _toEventObject(rawEvent) {
+  return {
+    // Category is typically devtools.main for us.
+    category: rawEvent[1],
+    // Method is the event's name (eg open, select_page etc...)
+    method: rawEvent[2],
+    // Object will usually be aboutdebugging for our tests
+    object: rawEvent[3],
+    // Value is usually empty for devtools events
+    value: rawEvent[4],
+    // Extras contain all the details of the event, including the session_id.
+    extras: rawEvent[5],
+  };
+}