The codebase was incredibly inconsistent with the use of spacing around
curly braces, e.g.:
```
// this?
const a = {b: 1}
// or?
const a = { b: 1 }
```
This extended into import statements also. Google's styleguide is no
spacing, so we're going with that.
Rather than maintain our own test runner we should instead lean on the community and use Mocha which is very popular and also our test runner of choice in DevTools too.
Note that this commit doesn't remove the TestRunner source as it's still used for other unit tests, but they will be updated in a future PR and then we can remove the TestRunner.
The main bulk of this PR is updating the tests as the old TestRunner passed in contextual data via the `it` function callback whereas Mocha does not, so we introduce some helpers for the tests to make it easier.
CSS stylesheets can still be parsed and added events emitted during the CSS.stopRuleUsageTracking call. It needs to be awaited before calling CSS.disable, otherwise the text content of those style sheets will be unavailable.
If nobody forces a layout, CSS coverage is inconsistent. This causes some flakes on the bots. The test in this PR fails 90% of the time on my local machine.
Chrome DevTools shows anonymous scripts with yellow background and names
them with `debugger://VM<scriptId>` prefix.
This patch starts reporting the same debugger:// urls for anonymous
scripts in puppeteer's JS coverage. This might simplify debugging, e.g.
using `debugger;` statement to reveal the script in DevTools and later
matching it against the one in the coverage.
This patch adds `reportAnonymousScripts` option to the `coverage.startJSCoverage` method. With this option, anonymous scripts are reported as well.
Fixes#2777
Today, we have tests split into multiple files, with files pulling
tests from some other files.
This patch starts explicitly gathering all tests from the same
`test.js` file.
Drive-By: move one test from `browser.spec.js` into `puppeteer.spec.js`
since it starts browser itself.