diff -r 000000000000 -r 6474c204b198 js/src/tests/README.txt
--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/js/src/tests/README.txt	Wed Dec 31 06:09:35 2014 +0100
@@ -0,0 +1,54 @@
+JS Test Suite Readme
+====================
+
+The JS test suite is a fairly extensive collection of correctness and regression
+tests for the Spidermonkey engine. Two harnesses run these tests: the shell test
+harness in this directory and the "reftest" harness built into the browser, used
+by Tinderbox. The browser reftests require additional manifest files; these are
+generated automatically by the build phase 'package-tests' using the
+'--make-manifests' option to jstests.py.
+
+Creating a test
+---------------
+For general information, see
+https://developer.mozilla.org/en-US/docs/SpiderMonkey/Creating_JavaScript_tests
+
+Adding a test
+-------------
+    Drop it in an appropriate directory under the tests directory.
+
+        <fineprint> Some names are forbidden. Do not name your test browser.js,
+        shell.js, jsref.js, template.js, user.js, js-test-driver-begin.js, or
+        js-test-driver-end.js, or any of the names of the files in supporting/.
+        </fineprint>
+
+Adjusting when and how a test runs
+----------------------------------
+    Put a comment at the top of the header matching the format:
+        // |reftest| <failure-type> -- <comment>
+
+    Where <failure-type> is a standard reftest <failure-type> string, as documented by:
+        http://mxr.mozilla.org/mozilla-central/source/layout/tools/reftest/README.txt
+
+    Example:
+        // |reftest| skip-if(!xulRuntime.shell) -- does not always dismiss alert
+
+        <fineprint> Either // or /* */ style comments may be used. The entire
+        comment must appear in the first 512 bytes of the file. The control
+        string must be in its own comment block. </fineprint>
+
+    When adding such comments to individual files is not feasible (e.g., for
+    imported tests), reftest manifest entries can be added to jstests.list
+    instead. Combining in-file comments with entries in this manifest file for
+    the same files is not supported (the one from the manifest file will be
+    used). Only the following two forms are supported:
+        <failure-type> include <relative_path>
+        <failure-type> script <relative_path>
+    The <type> "include" indicates that <failure-type> should apply to all test
+    cases within a directory. A statement for a nested directory or script
+    overrides one for an enclosing directory.
+
+Running tests
+-------------
+See
+https://developer.mozilla.org/en-US/docs/SpiderMonkey/Running_Automated_JavaScript_Tests