doc: Documentation for test specifcation generate

doc/testing.md

@@ -281,6 +281,36 @@ or, when running interactively:
     $ make test-sh
     09:08:17 infamy0:test # ./9pm/9pm.py -o"--transport=restconf" case/ietf_system/hostname.py
 
+### Test specification
+
+The test specification is automaticly generated from the test cases,
+this put some constaints on the test cases:
+
+All test cases must be written so that it can be understandable with
+only the steps so the result can be reproduced
+manually. For example: Intead of `set ip address on
+the interface` it should be more human readable, for example:
+
+```
+test.step("Set IPv4 address on the interface dut:cross")
+test.step("Verify the IP address is set on dut:cross")
+
+```
+where dut, cross and the IPv4 address could be found inside the
+logical topology for the test.
+
+Each test case must begin with the test name followed by a empty line and
+the description of the test. For example:
+
+```
+Set hostname
+
+Verify that it it possible to change hostname
+```
+
+The test specifaction can be genererated with:
+
+	$ make test-spec
 
 [9PM]:    https://github.com/rical/9pm
 [Qeneth]: https://github.com/wkz/qeneth