Automatic failing/non-execution of interdependent tests in Robot Framework

Vikraant Singh Sanwal picture Vikraant Singh Sanwal · Aug 1, 2014 · Viewed 7.6k times · Source

I have a large number of test cases, in which several test cases are interdependent. Is it possible that while a later test case is getting executed you can find out the status of a previously executed test case? In my case, the 99th test case depends on the status of some prior test cases and thus, if either the 24th or the 38th fails I would like the 99th test case NOT to get executed at all and thus save me a lot of time. Kindly, explain with some example if possible. Thanks in advance!

Answer

Bryan Oakley picture Bryan Oakley · Aug 1, 2014

Once robot starts running, there's no way to skip a test based on some condition. I think this is one of the weaknesses of robot, but the designers really don't seem to like the notion of skipped tests. Also, there's no built-in way for one test to depend on another. A feature request for this very feature was declined.

However, robot is very extensible, and a feature that was introduced in version 2.8.5 makes it easy to write a keyword that will fail if another test has failed.This feature is the ability for a library to act as a listener. With this, a library can keep track of the pass/fail status of each test. With that knowledge, you can create a keyword that fails immediately if some other test fails.

The basic idea is, cache the pass/fail status as each test finishes (via the special _end_test method). Then, use this value to determine whether to fail immediately or not.

Here's an example of how to use such a keyword:

*** Settings ***
| Library | /path/to/DependencyLibrary.py

*** Test Cases ***
| Example of a failing test
| | fail | this test has failed

| Example of a dependent test
| | [Setup] | Require test case | Example of a failing test
| | log | hello, world

Here is the library definition:

from robot.libraries.BuiltIn import BuiltIn

class DependencyLibrary(object):
    ROBOT_LISTENER_API_VERSION = 2
    ROBOT_LIBRARY_SCOPE = "GLOBAL"

    def __init__(self):
        self.ROBOT_LIBRARY_LISTENER = self
        self.test_status = {}

    def require_test_case(self, name):
        key = name.lower()
        if (key not in self.test_status):
            BuiltIn().fail("required test case can't be found: '%s'" % name)

        if (self.test_status[key] != "PASS"):
            BuiltIn().fail("required test case failed: '%s'" % name)

        return True

    def _end_test(self, name, attrs):
        self.test_status[name.lower()] = attrs["status"]