Improve HTML test results reports

[ianbrandt]

Expected Behavior

It would be really handy if the columns of the HTML test results report were sortable, and if there was a "Tests" (i.e. a listing of the individual test methods) view in addition to the "Packages" and "Classes" views.

Then I could select the "Tests" view, sort by "Duration" descending, and quickly see my slowest tests across all my test suites. Combined with the Test Report Aggregation Plugin, I could see my slowest tests across all my suites for my entire build.

Current Behavior (optional)

I can't readily see my overall slowest tests via the HTML test results report.

Context

Regularly identifying and performance tuning my slowest tests could significantly reduce my overall build times. My CI server (Bamboo) doesn't seem to derive any such report from the XML test results. I'd have to find some other tooling, or somehow code something myself that would produce such a report.

[ianbrandt]

On concern I could foresee is that an aggregate "Tests" view that contains many hundreds of thousands of individual tests or more could start to become a problem for page rendering performance and memory consumption. The simplest way to address this might be to make the view optional, have it be disabled by default, and slap a "caveat emptor" sticker on it in the documentation. Alternatively, the results could written out to JSON (perhaps chunked), and a JavaScript pagination or top-N control could be used to only render a limited slice of the results at one time.

[ljacomet]

This feature request is in the backlog of the relevant team and is prioritized by them.

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If you are interested in contributing to Gradle, this issue is actionable and ready for contribution but might be challenging for first-time contributors.

See CONTRIBUTING.md for more information.

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The request makes sense. The implementation should remain self-contained because that report is designed for external consumption.