1 files changed, 45 insertions, 0 deletions
diff --git a/devtools/client/accessibility/utils/audit.js b/devtools/client/accessibility/utils/audit.js
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index 0000000000..6234e711f1
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+++ b/devtools/client/accessibility/utils/audit.js
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+/* 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";
+
+/**
+ * A helper class that contains the state of the audit progress performed by
+ * the accessibility panel. Its onProgressForWalker function wraps around the
+ * onProgress function (see actions/audit.js) that updates the panel state. It
+ * combines the audits across multiple frames that happen asynchronously. It
+ * only starts dispatching/calling onProgress after we get an initial progress
+ * audit-event from all frames (and thus know the combined total).
+ */
+class CombinedProgress {
+  constructor({ onProgress, totalFrames }) {
+    this.onProgress = onProgress;
+    this.totalFrames = totalFrames;
+    this.combinedProgress = new Map();
+  }
+
+  onProgressForWalker(walker, progress) {
+    this.combinedProgress.set(walker, progress);
+    // We did not get all initial progress events from all frames, do not
+    // relay them to the client until we can calculate combined total below.
+    if (this.combinedProgress.size < this.totalFrames) {
+      return;
+    }
+
+    let combinedTotal = 0;
+    let combinedCompleted = 0;
+
+    for (const { completed, total } of this.combinedProgress.values()) {
+      combinedTotal += total;
+      combinedCompleted += completed;
+    }
+    this.onProgress({
+      total: combinedTotal,
+      percentage: Math.round((combinedCompleted / combinedTotal) * 100),
+    });
+  }
+}
+
+exports.CombinedProgress = CombinedProgress;
+exports.isFiltered = filters => Object.values(filters).some(active => active);