fix(runner): Do not persist grep option across runs

[jvalkeejarvi]

Fix for #2819.

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[jvalkeejarvi]

I signed it!

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[johnjbarton]

I'm unsure what your design goal is here. I would have expected that client.args would be the original config args unless explicitly overridden by the command line. That is what 'original' would mean to me.

But the code persists the previous values.

Maybe you want to move the save calls outside of the response handler, just inside the create() call where config comes in. Then the restore call can be unconditional every time the handler executes. That would be simpler and I think less surprising usage.

[jvalkeejarvi]

Maybe you want to move the save calls outside of the response handler, just inside the create() call where config comes in.

What create call do you mean?

Sorry I'm a bit confused. This is my first PR to this repo so I'm not that familiar with the codebase.

[johnjbarton]

Sorry I meant createRunnerMiddleware()
https://github.com/karma-runner/karma/blob/master/lib/middleware/runner.js#L15

Quite a bit of karma-runner code has node modules exporting createXX functions that return functions. The arguments of the createXX functions are closed over in the returned functions.

[jvalkeejarvi]

Calling helper.saveOriginalArgs() outside response handler (just after this line https://github.com/karma-runner/karma/blob/master/lib/middleware/runner.js#L15) is a bit problematic in tests.

createRunnerMiddleware() is called in beforeEach

karma/test/unit/middleware/runner.spec.js

Line 59 in c3ce1f3

handler = createRunnerMiddleware(

but config.client.args is set in test case itself.

karma/test/unit/middleware/runner.spec.js

Line 235 in c3ce1f3

config = _.merge(config, {client: {args: run.existingConfig}})

As a result config.client.originalArgs is always left undefined in tests. I don't know if tests can be fixed without major changes. What do you think?

[johnjbarton]

I think you can redefine handler just before it is called in the clientArgs test, with a bonus if you wrap the non-clientArgs tests in a describe() block with beforeEach() setting handler for those tests (so the handler is not redefined.

Maybe its not too hard?

[johnjbarton]

Nice, thanks!