Refactor the backstab unit test

[stevecotton]

Based on part of Pentarctagon's #6308, and also improving
the encapsulation of the test to take a boolean value for whether
the ability should be active instead of the expected damage total.

[Wedge009]

I'm not very familiar with WML tests but as a general rule I try to write self-descriptive names for the tests in preference to overly-long explanatory comments as the latter can become out of date as code/tests are updated. As I recall, back-stab doubles damage for the attacker when an attacker's ally is directly opposite the defender. But it looks like the test names are pre-existing and I assume they haven't been changed to avoid breaking tests.

It makes sense to me to have the test focus on the activation of the back-stab damage bonus vs checking arbitrary damage values in the parameters as the latter seems more prone to errors.

[stevecotton]

It would be easy to change the tests' names too, please provide better suggestions.
The name just has to match in the test and in the wml_test_schedule file.

[Wedge009]

I don't know what the convention is, but if I understood the tests correctly I was thinking along the lines of:

• TEST_BACKSTAB "backstab_should_activate_with_attacker_ally_behind_defender"
• TEST_BACKSTAB "backstab_should_not_activate_without_attacker_ally_behind_defender"
• TEST_BACKSTAB "backstab_should_not_activate_with_disabled_attacker_ally_behind_defender"
• TEST_BACKSTAB "backstab_should_not_activate_with_defender_ally_behind_defender"

A bit long, I know, but at least it should be clear to a newcomer what the tests are checking for.

[stevecotton]

A bit long, I know, but at least it should be clear to a newcomer what the tests are checking for.

A bit shorter (haven't pushed it yet, still pondering):

• backstab_active_with_accomplice_behind_bob
• backstab_inactive_with_triangular_formation
• backstab_inactive_with_statue_behind_bob
• backstab_inactive_with_bobs_ally_behind_bob

[Wedge009]

As long as people reading can quickly and easily understand the intent of the test solely by looking at the test name. I find that's generally easier to accomplish when being a bit more verbose but whatever works.

[stevecotton]

Are the ones that I posted clear to you, or not?

[Wedge009]

It should be fine - definitely an improvement over the original anyway.

[stevecotton]

@Pentarctagon, is this OK for you?