1 files changed, 59 insertions, 0 deletions
diff --git a/browser/components/newtab/loaders/inject-loader.js b/browser/components/newtab/loaders/inject-loader.js
new file mode 100644
index 0000000000..8729baf270
--- /dev/null
+++ b/browser/components/newtab/loaders/inject-loader.js
@@ -0,0 +1,59 @@
+/* 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/. */
+
+// Note: this is based on https://github.com/plasticine/inject-loader,
+// patched to make istanbul work properly
+
+const loaderUtils = require("loader-utils");
+const QUOTE_REGEX_STRING = "['|\"]{1}";
+
+const hasOnlyExcludeFlags = query =>
+  Object.keys(query).filter(key => query[key] === true).length === 0;
+const escapePath = path => path.replace("/", "\\/");
+
+function createRequireStringRegex(query) {
+  const regexArray = [];
+
+  // if there is no query then replace everything
+  if (Object.keys(query).length === 0) {
+    regexArray.push("([^\\)]+)");
+  } else if (hasOnlyExcludeFlags(query)) {
+    // if there are only negation matches in the query then replace everything
+    // except them
+    Object.keys(query).forEach(key =>
+      regexArray.push(`(?!${QUOTE_REGEX_STRING}${escapePath(key)})`)
+    );
+    regexArray.push("([^\\)]+)");
+  } else {
+    regexArray.push(`(${QUOTE_REGEX_STRING}(`);
+    regexArray.push(
+      Object.keys(query)
+        .map(key => escapePath(key))
+        .join("|")
+    );
+    regexArray.push(`)${QUOTE_REGEX_STRING})`);
+  }
+
+  // Wrap the regex to match `require()`
+  regexArray.unshift("require\\(");
+  regexArray.push("\\)");
+
+  return new RegExp(regexArray.join(""), "g");
+}
+
+module.exports = function inject(src) {
+  if (this.cacheable) {
+    this.cacheable();
+  }
+  const regex = createRequireStringRegex(
+    loaderUtils.urlToRequest(this.resourcePath) || {}
+  );
+
+  return `module.exports = function inject(injections) {
+  var module = {exports: {}};
+  var exports = module.exports;
+  ${src.replace(regex, "(injections[$1] || /* istanbul ignore next */ $&)")}
+  return module.exports;
+}\n`;
+};