"Run Keyword And Ignore Error" - what is it useful for?

Question

In Robot Framework, there is a keyword Run Keyword And Ignore Error.

From the manual:

Runs the given keyword with the given arguments and ignores possible error.

This keyword returns two values, so that the first is either 'PASS' or 'FAIL', depending on the status of the executed keyword. The second value is either the return value of the keyword or the received error message. See Run Keyword And Return Status. If you are only interested in the execution status.

The keyword name and arguments work as in Run Keyword. See Run Keyword If for a usage example.

In which situations is this keyword useful?

If I want to continue my test after a failed keyword, I use Run Keyword And Continue On Failure, in this case I can see in the test report that there was a failed keyword in the test (I don't see it using Run Keyword And Ignore Error). If I need a status of the executed keyword (and want to continue my test if this keyword failed), I use Run Keyword And Return Status.

So what are the cases which cannot be covered with either Run Keyword And Continue On Failure or Run Keyword And Return Status?

Answer 1

I have used it when doing an If statement, actually in the documentation that you pasted It says exactly that!

The keyword name and arguments work as in Run Keyword. See Run Keyword If for a usage example.

So that would be a good place to see an example of it use

Run keyword if is a keyword for starting if statements:

Runs the given keyword with the given arguments, if condition is true.

And an example:

|${status} | ${value}= | Run Keyword And Ignore Error | My Keyword
| Run Keyword If | '${status}' == 'PASS' Some Action arg ELSE Another Action

Answer 2

I use Run Keyword and Ignore Error for test setup that is not an essential part of the test.

For example, I may need to delete an object that may or may not be there. It can be easier to just say:

| Run Keyword and Ignore Error | Delete Object | Potential-Object-Name |

Answer 3

In a technical sense Run Keyword And Ignore Error is no different from the other two. However, to me the value is in the name of the keyword itself and how it expresses human intention.

Even though you could technically prevent test failure by using Run Keyword And Return Status it would not be as clear as Run Keyword And Ignore Error 12 months after you've written the code, or when some new person comes in and reads the code for the first time.

Answer 4

In which situations is this keyword useful?

This keyword is useful in a negative scenario: For example you have a login_keyword that succeeded with the proper credentials and fails with wrong one. You have to test that if the user doesn't login with 3 unsuccessful attempts with wrong credential then block the user with the appropriate message on the fourth try. So you are making a 4 loops with unsuccessful login and if you use:

Run Keyword And Continue On Failure | login_keyowrd | @{wrongCredentials}

After the loop finishes and you successfully assert that the user is blocked with the appropriate message the test will be marked as failed in the report, despite the assert of the last step is passed.

If you use Run Keyword And Ignore Error | login_keyowrd | @{wrongCredentials} Then the test will be marked as a PASSED as it is expected to the scenario.

You can complete the scenario of course as stated in the accepted answer:

|${status} | ${value}= | Run Keyword And Ignore Error | login_keyowrd |
Run Keyword If | '${status}' == 'PASS' | Some Action arg | ELSE | Another Action |

But this is one step more instead of using the keyword that you are asking in the question.

Hope it's more clear now.