Implement the only modifier.

[lijunle]

DO NOT MERGE

Resolve #132

I hack the test count number to show the right number and passed cases number. From my understand, such information should be pass through the promise chain.

Besides, ava.serial.only has no support in this PR yet.

/cc @vdemedes @sindresorhus

---

Screenshot:

[lijunle]

The variable testCount is maintained by the addTest, addOnlyTest, addSerialTest function, which I think that is not suitable. A better way is to return such information (testCount, failCount) from the promise, then calculate the final stats from at the end of the chain.

However, it involves more code change if doing so. Any ideas?

[vadimdemedes]

I think it's perfectly fine, I wouldn't call it a hack.

[sindresorhus]

Awesome @lijunle :) Both @vdemedes and I are traveling, so we probably won't be able to review this until monday.

// @jamestalmage

[lijunle]

@sindresorhus That is OK, please keep in mind that, there is a hack. I am not going to merge until resolve the hack with a good way (unless a direction).

[vadimdemedes]

it can be just return self.concurrent(tests.only), since tests.only defaults to [].

[vadimdemedes]

Everything looks good so far, I pointed out some things in the diff. One question I have in mind, should only tests be executed serially on in parallel? Btw, mocha allows only one only test, so maybe we should also do that? And it would solve the serial vs parallel question too.

[lijunle]

One question I have in mind, should only tests be executed serially on in parallel?

My question is no. If the guy wants to do so, he should do ava.serial.only. However such API is not implemented in this RP.

Btw, mocha allows only one only test, so maybe we should also do that?

Mocha allow several only modifiers. For example, if there are 10 test cases, and 3 of them are marked as only, those 3 test cases will be run.

[vadimdemedes]

Mocha allow several only modifiers. For example, if there are 10 test cases, and 3 of them are marked as only, those 3 test cases will be run.

I guess I was running some out-dated version then.

[vadimdemedes]

@lijunle Could you please rebase your PR (to pick up latest fixes for windows tests) and address comments in the diff? Happy to merge this ASAP.

[lijunle]

OK, do you want to modify the comment about the hack?

[vadimdemedes]

Yeah, the comment is not really needed and this - https://github.com/sindresorhus/ava/pull/204/files#r45035490

[lijunle]

Rebased, let us wait for the CI. 😸

---

However, although I removed the comment, I still consider that is a hack.

The stats should be collected from _runTestWithHooks function and pass back to the promise chain in the Runner.prototype.run function. At the end of the promise chain, calculate the final stats from the input.

Code like this:

Runner.prototype.run = function () {
    var self = this;
    return eachSeries(tests.before, this._runTest.bind(this)) // resolve with { pass: 1, failed: 2, skipped: 3 }
        .then(function (stats) {
            return Object.assign(stats, self.serial(tests.serial)); // i.e. { pass: 2, failed: 3, skipped: 4 }
        })
        .then(function (stats) {
            return Object.assign(stats, self.concurrent(tests.concurrent)); // object with { pass, failed, skipped }
        })
        .then(function (stats) {
            return Object.assign(stats, eachSeries(tests.after, self._runTest.bind(self))); // object with { pass, failed, skipped }
        })
        .then(function (stats) {
            self.stats.passCount = stats.pass; // calculate from the input of promise chain.
            return stats; // external check could depends on return value of run function, more stable. 
        });
};

[vadimdemedes]

The refactoring and cleanup work is ahead, so don't worry about this 1 line ;)

[lijunle]

I understand. It is up to you to design the pattern, that is just my suggestion.

[jamestalmage]

@lijunle

I was actually taking a stab at this earlier when I got pulled away to some other stuff.
Since you are pretty far down the road, I am holding off.

I just squashed my work and pushed it up: jamestalmage@4568347

Use it if it helps.

My other thoughts.

1. I would really like to avoid the Mocha behavior of only allowing a single test in exclusive mode. I want to be able to put only on however many tests I chose and have them be the ones that run. This is especially important since we don't have grouping yet.
2. I like your idea of test.serial.only, etc.
3. I think creating stats at the beginning is making all this hard. Just put flags in each individual test and use this.tests.concurrent.filter to create the stats and get at the tests you want (see the diff I linked).

Good work! And thanks for the help.

[vadimdemedes]

@lijunle Thank you!

[sindresorhus]

@jamestalmage Any improvements welcome in a follow-up pull request ;)

[jamestalmage]

Yeah, sorry!
I've got a lot going on today and am lagging way behind the conversation.