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+
+# Writing Tests
+
+There are several sources of GCLI tests and several environments in which they
+are run.
+
+The majority of GCLI tests are stored in
+[this repository](https://github.com/joewalker/gcli/) in files named like
+```./lib/gclitest/test*.js```. These tests run in Firefox, Chrome, Opera,
+PhantomJS, and NodeJS/JsDom
+
+See [Running Tests](running-tests.md) for further details.
+
+GCLI comes with a generic unit test harness (in ```./lib/test/```) and a
+set of helpers for creating GCLI tests (in ```./lib/gclitest/helpers.js```).
+
+# GCLI tests in Firefox
+
+The build process converts the GCLI tests to run under Mochitest inside the
+Firefox unit tests. It also adds some