1 files changed, 65 insertions, 0 deletions
diff --git a/browser/components/newtab/tools/resourceUriPlugin.js b/browser/components/newtab/tools/resourceUriPlugin.js
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+++ b/browser/components/newtab/tools/resourceUriPlugin.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/. */
+
+// This plugin supports finding files with particular resource:// URIs
+// and translating the uri into a relative filesytem path where the file may be
+// found when running within the Karma / Mocha test framework.
+
+module.exports = {
+  ResourceUriPlugin: class ResourceUriPlugin {
+    /**
+     * @typedef {RegEx} ResourceReplacement0
+     *   A regular expression matching a resource:// URI substring to be
+     *   replaced.
+     * @typedef {string} ResourceReplacement1
+     *   A string to replace the matched substring with.
+     * @typedef {[ResourceReplacement0, ResourceReplacement1]} ResourceReplacement
+     */
+
+    /**
+     * Maps regular expressions representing resource URIs to strings that
+     * should replace matches for those regular expressions.
+     *
+     * @type {ResourceReplacement[]}
+     */
+    #resourcePathRegExes;
+
+    /**
+     * @param {object} options
+     * @param {ResourceReplacement[]} options.resourcePathRegExes
+     *   An array of regex/string tuples to perform replacements on for
+     *   imports involving resource:// URIs.
+     */
+    constructor({ resourcePathRegExes }) {
+      this.#resourcePathRegExes = resourcePathRegExes;
+    }
+
+    apply(compiler) {
+      compiler.hooks.compilation.tap(
+        "ResourceUriPlugin",
+        (compilation, { normalModuleFactory }) => {
+          normalModuleFactory.hooks.resolveForScheme
+            .for("resource")
+            .tap("ResourceUriPlugin", resourceData => {
+              const url = new URL(resourceData.resource);
+
+              for (let [regex, replacement] of this.#resourcePathRegExes) {
+                if (!url.href.match(regex)) {
+                  continue;
+                }
+                const pathname = url.href.replace(regex, replacement);
+                resourceData.path = pathname;
+                resourceData.query = url.search;
+                resourceData.fragment = url.hash;
+                resourceData.resource = pathname + url.search + url.hash;
+                return true;
+              }
+
+              return true;
+            });
+        }
+      );
+    }
+  },
+};