Add timeout option to xits using arrow functions

[MattOakley]

Prerequisites

• Checked that your issue isn't already filed by cross referencing issues with the common mistake label
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  node node_modules/.bin/mocha --version(Local) and mocha --version(Global). We recommend avoiding the use of globally installed Mocha.

Description

When using the arrow function syntax to override the default timeout. You specifiy it on the return value of the it function.

it("should override the timeout", () => { }).timeout(100);

But if we want to ignore the test by adding an x we get an exception, which is annoying.

Steps to Reproduce

// Throws
xit("should override the timeout", () => { }).timeout(100);

Expected behavior: The test should be ignored

Actual behavior: We get an exception

Mocha` exploded!
TypeError: Cannot read property 'timeout' of undefined

Reproduces how often: 100%

Versions

mocha 4.0.1

[boneskull]

Is this a documented API? I don't recall ever seeing anyone use this before.

[boneskull]

anyway, this looks pretty trivial to address. I'm going to call it a bug even though it's more of an "internal consistency" issue, since we don't necessarily expect consumers to use the object returned from it or xit for anything.

[Bamieh]

@boneskull this is a very interesting side effect of returning the test object from inside the it function. I have a PR coming in a few.

[boneskull]

@Bamieh I've already got one ready ;)

[boneskull]

@Bamieh beat me to it