Lazily execute beforeAll/afterAll code blocks (with grep)

[nonplus]

When using grep, I would like only the beforeAll/afterAll blocks needed by tests matching my grep to be executed.

Currently all beforeAll and afterAll callbacks get executed, regardless of whether any tests being run depend on them.

If you have a large test suite that uses beforeAll blocks to consolidate expensive setup, using grep to isolate a test may not speed up the run all that much because of this.

In the following example, when running mocha --grep Files I would expect "expensive setup needed for Database suite" not to be executed.

describe("Database", function() {
    beforeAll(function() {
        // expensive setup needed for Database suite
    });
    ...
});

describe("File", function() {
    beforeAll(function() {
        // expensive setup needed for File suite
    });
    ...
});

[guybrush]

+1

i run into this issue a lot

[tj]

ah good call, I'll see if I can get this in the next release

[nonplus]

@visionmedia, I've got an initial implementation that's working for me, but I'm not sure if that's the approach you would have taken. I also need to provide tests. Let me know if you want me to flesh this out and do a pull request.

BTW, I noticed a bug where if you specify multiple before/afterAll hooks, only one gets executed. My patch has that fixed (calling hookUp/Down instead of hook).

https://github.com/nonplus/mocha/commits/lazy-all

[tj]

This issue has been inactive for over 1 month so I'm closing it. If you think it's still an issue re-open. - tjbot