wrote "Writing test files" section in Readme.md

README.md

@@ -6,6 +6,47 @@ Before reading this section, make sure you've read the [DuckDuckHack Intro Site]
 ### Example
 ![morse code example](https://s3.amazonaws.com/ddg-assets/docs/goodie_example.png)
 
+## Writing test files
+
+Every goodie includes a test file in the `t` directory. For example, the **RouterPasswords** goodie uses the the test file `t/RouterPasswords.t`. This test file includes sample queries and answers, and is run automatically before every release to ensure that all goodies are triggering properly with correct answers. The test file is a Perl program that uses the Perl packages `DDG::Test::Goodie` and `Test::More` to function. Here's an annotated excerpt from `t/RouterPasswords.t` that you can use as a base:
+
+```
+#!/usr/bin/env perl
+
+use strict;
+use warnings;
+use Test::More;
+use DDG::Test::Goodie;
+
+# These zci attributes aren't necessary, but if you specify them inside your goodie,
+# you'll need to add matching values here to check against.
+zci answer_type => 'password';
+zci is_cached => 1;
+
+ddg_goodie_test(
+	[
+        # This is the name of the goodie that will be loaded to test.
+		'DDG::Goodie::RouterPasswords'
+    ],
+    # This is a sample query, just like the user will enter into the DuckDuckGo search box
+	'Belkin f5d6130' =>
+        test_zci(
+            # The first argument to test_zci is the plain text (default) returned from a goodie.
+            # If your goodie also returns an HTML version, you can pass that along explicitly as
+            # the second argument. If your goodie is random, you can use regexs instead of
+            # strings to match against.
+            'Default login for the BELKIN F5D6130: Username: (none) Password: password',
+            html => 'Default login for the BELKIN F5D6130:<br><i>Username</i>: (none)<br><i>Password</i>: password'
+        ),
+    # You should include more test cases here. Try to think of ways that your plugin
+    # might break, and add them here to ensure they won't.
+);
+
+done_testing;
+```
+
+Once you've written a test file, you can test it on it's own with `perl -Ilib t/GoodieName.t`.
+
 ## Advanced Goodies
 These advanced handle techniques are specific to Goodie plugins: