chore: properly isolate module tests

[Narretz]

What kind of change does this PR introduce? (Bug fix, feature, docs update, ...)

What is the current behavior? (You can also link to an open issue here)
Previously, our module tests weren't running in isolation. Theroetically, we wanted to test if the angular.js build file works well with the individual module source files (Note that we don't use the module build files because we sometimes test non-public apis).
However, we bundled all module files together with the build file, and this messed up the results as some modules assign angular helpers like isDefined in the current scope, which means all following modules have access to them too, which essentially defeats the purpose of these tests. See #16702.

What is the new behavior (if this is a feature change)?

Does this PR introduce a breaking change?

Please check if the PR fulfills these requirements

• The commit message follows our guidelines
• Fix/Feature: Docs have been added/updated
• Fix/Feature: Tests have been added; existing tests pass

Other information:

[gkalpak]

Does this have to be here? Can't it shadow problems as before (e.g. modules depending on stuff that is defined in ngMock's source code)?

[Narretz]

the angular-mocks file defines the module fn that integrates with jasmine, so I think it unfortunately must always be included:

angular.js/src/ngMock/angular-mocks.js

Line 3085 in bb5a7e3

var module = window.module = angular.mock.module = function() {

[gkalpak]

But we get the same integration with build/angular-mocks.js, right? (Without the problem of making things defined in the ngMocks closure available to other modules.)

I would expect build/angular-mocks.js to be included in all module tests, except for ngMocks specs, which should indeed use src/ngMock/*.js. Do I miss something?

[Narretz]

Using build/angular-mocks.js works great, good suggestion!
In the beginning, it was a big hassle to separate all these files, it's possible that at some point the ngMock src files had to be included.

[gkalpak]

Hm... 🤔
Why is this necessary?

[Narretz]

Some tests in ngMessages are dependent on ngAnimate, e.g.

angular.js/test/ngMessages/messagesSpec.js

Line 465 in bb5a7e3

module('ngAnimate');

[gkalpak]

Do we still need ngAnimate if we use ngAnimateMock?

[Narretz]

Theoretically yes, but I'm more comfortable with testing the actual animations instead of just the base provided by ng.

[gkalpak]

Hm... 🤔
Why is this necessary?

[Narretz]

There's a test that uses ngResource:

angular.js/test/ngMock/angular-mocksSpec.js

Line 1114 in bb5a7e3

'ngResource',

I think we could use a custom module here instead.

[gkalpak]

👍 for using a custom module.