x/build: modify contents of "gray box" (summary markdown) in LUCI UI to be more directly to the point for test failures

[mknyszek]

Currently the LUCI UI for Go builds isn't very direct, especially in the common case of a test failure.

For example:

The "FAILURE" line is redundant, the "exit status 1" line is also not very useful (more useful for an infra failure, less useful for a test failure), and the "Links" section has only one link that goes to a more verbose set of information. Nowhere here do we link to the test results directly (we do for main Go repo builds, but that also includes less useful information, like the shard number).

@rsc proposed including a summary of the test failure text instead, which I believe is the right call. We already plumb around the fact that a test failed anyway.

I'll defend the existence of the go on <x> and website on <y> lines, because I don't believe that information is surfaced very well anywhere else in the UI, but other than that, the summary markdown could use a rethink.

[rsc]

On https://go-review.googlesource.com/c/go/+/583455 PS1:

• the blue arrow in the chip links to https://cr-buildbucket.appspot.com/build/8748684851461439681.
• the "Tryjob golang/try/gotip-linux-386 has failed" comment links golang/try/gotip-linux-386 to https://cr-buildbucket.appspot.com/build/8748684851461439681.

Can these URLs be changed to https://ci.chromium.org/ui/p/golang/builders/try/gotip-linux-386/b8748684851461439681/test-results instead?

You showed me how to change the default behavior to not go to the Overview page, but we know the Test Results are the right landing page for users viewing a failure on a Gerrit page. Let's link directly there, so that we don't have to train everyone to change their defaults. (If everyone has to change their defaults, the defaults are wrong.)

[rsc]

For the record, these are the magic places to click to get one-click viewing of test results.

The first time you click on one of those, you have to also edit your LUCI config to default to "Test Results":

Editing the config works even if you are not logged in. It stores the result in Local Storage. Mine says:

{"id":...,"build":{"steps":{"elideSucceededSteps":true,"showDebugLogs":false,"expandByDefault":1,"_pinnedSteps":{"_values":{}}},"inputProperties":{"_foldedRootKeys":{"_values":{}}},"outputProperties":{"_foldedRootKeys":{"_values":{}}},"defaultTab":"test-results"},"tests":{"_columnWidths":{"v.test_suite":350}}}

[mknyszek]

FYI, I'm landing a few CLs that should improve the state of things here. They are:

• https://chromium-review.googlesource.com/c/infra/infra/+/5551106
  • Fixes an oversight where the test results link wouldn't show up in the gray box for subrepo builds that failed.
• https://chromium-review.googlesource.com/c/infra/infra/+/5551107
  • Adds make.bash to the structured test results, so the "test results" tab becomes more of a one-stop shop. Once we have have go build -json (cmd/go: go build -json #62067) then we can put all build failures in this tab.
• https://chromium-review.googlesource.com/c/infra/infra/+/5551108
  • This CL actually implements the suggestions from the original post to this issue, minus the "surface test failures in the gray box," which is a bit harder.