Updated Development (markdown)

Development.md

@@ -14,7 +14,7 @@ More details can be found in the [API documentation](https://zerobin.dssr.ch/doc
 
 ## Unit Tests
 
-For unit tests of the php code the folder `tst/` should be used. Apart from helping to implement new features correctly it should help us to keep regressions at bay. By default a code coverage report is generated after phpunit is run, the one of the latest release is [publicly available](https://zerobin.dssr.ch/coverage-report/).
+For unit tests of the php code the folder `tst/` can be used. Apart from helping to implement new features correctly it helps to keep regressions at bay. By default a code coverage report is generated after phpunit is run, the one of the latest release is [publicly available](https://zerobin.dssr.ch/coverage-report/).
 
 In order to run these tests, you will need the following packages and its dependencies:
 * phpunit
@@ -31,6 +31,14 @@ To run the tests, just change into the `tst/` directory and run phpunit:
     $ cd ZeroBin/tst
     $ phpunit
 
+Additionally there is the `configGenerator`. Based on the configurations defined in its constructor, it generates the unit test file `tst/configuration.php`, containing all possible combinations of these configurations and test for (most) valid combinations. Some of combinations can't be tested with this method, i.e. a valid option combined with an invalid one. Other very specific test cases (i.e. to trigger multiple errors) are covered in `tst/zerobin.php`. Here is how to generate the configuration test and run it:
+
+    $ cd ZeroBin/tst
+    $ php configGenerator.php
+    $ phpunit configuration.php
+
+Note that it can take an hour or longer to run the several thousand tests.
+
 ## Data Model
 
 If you want to create your own data models, you might want to know how the arrays, that you have to store, look like: