1 files changed, 43 insertions, 0 deletions
diff --git a/devtools/client/framework/test/browser_source_map-no-race.js b/devtools/client/framework/test/browser_source_map-no-race.js
new file mode 100644
index 0000000000..23751f7bc8
--- /dev/null
+++ b/devtools/client/framework/test/browser_source_map-no-race.js
@@ -0,0 +1,43 @@
+/* Any copyright is dedicated to the Public Domain.
+ http://creativecommons.org/publicdomain/zero/1.0/ */
+
+// Test that the source map service doesn't race against source
+// reporting.
+
+"use strict";
+
+const JS_URL = URL_ROOT + "code_bundle_no_race.js";
+
+const PAGE_URL = `data:text/html,
+<!doctype html>
+
+<html>
+  <head>
+    <meta charset="utf-8"/>
+    <title>Empty test page to test race case</title>
+  </head>
+
+  <body>
+    <script src="${JS_URL}"></script>
+  </body>
+
+</html>`;
+
+const ORIGINAL_URL = "webpack:///code_no_race.js";
+
+const GENERATED_LINE = 84;
+const ORIGINAL_LINE = 11;
+
+add_task(async function () {
+  // Start with the empty page, then navigate, so that we can properly
+  // listen for new sources arriving.
+  const toolbox = await openNewTabAndToolbox(PAGE_URL, "webconsole");
+  const service = toolbox.sourceMapURLService;
+
+  info(`checking original location for ${JS_URL}:${GENERATED_LINE}`);
+  const newLoc = await new Promise(r =>
+    service.subscribeByURL(JS_URL, GENERATED_LINE, undefined, r)
+  );
+  is(newLoc.url, ORIGINAL_URL, "check mapped URL");
+  is(newLoc.line, ORIGINAL_LINE, "check mapped line number");
+});