x/tools/gopls: collect bug stack counter

[hyangah]

• Counter: gopls/bug
• Title: Number of bug report calls
• Description: count the bugs reported through gopls/internal/bug APIs
• Type: stack
• Depth: 16
• Issue: https://go.dev/issues/62249
• Program: golang.org/x/tools/gopls
• Version: v0.13.0

Why?

For rare situations where our assumption doesn't hold and gopls cannot proceed normally,
gopls calls this api. This stack counter counts how frequently this situation happens
and what assumption (code location) was violated. This information allows us to discover
and address the bugs.

Alternatives are either 1) crashing or 2) asking users to report when they notice it.
Neither is ideal or scalable.

Does it carry sensitive user information?

No.
This includes only the gopls's stack trace which doesn't include user information.

How?

https://github.com/golang/tools/blob/master/gopls/internal/bug/bug.go#L69
https://github.com/golang/tools/blob/0a044c0b5b3c2becb2e8ef5d92acca07f6ab8b60/gopls/internal/bug/bug.go#L105-L107

note: The default is 'local' which does not send any data to the telemetry server. Users must opt-in explicitly.

[gopherbot]

Change https://go.dev/cl/528295 mentions this issue: internal/configgen: add approved new gopls counters