x/tools/gopls: "nil metadata for %q" panic in Snapshot.getPackageHandles (reported by telemetry)

[adonovan]

This stack j8z9tw was reported by telemetry:

getPackageHandles.func1:+6 is:

			if mp == nil {
				panic(fmt.Sprintf("nil metadata for %q", id))
			}

crash/crash
runtime.gopanic:+69
golang.org/x/tools/gopls/internal/cache.(*Snapshot).getPackageHandles.func1:+6
golang.org/x/tools/gopls/internal/cache.(*Snapshot).getPackageHandles.func1:+23
golang.org/x/tools/gopls/internal/cache.(*Snapshot).getPackageHandles:+48
golang.org/x/tools/gopls/internal/cache.(*Snapshot).forEachPackage:+8
golang.org/x/tools/gopls/internal/cache.(*Snapshot).PackageDiagnostics:+28
golang.org/x/tools/gopls/internal/cache.(*Snapshot).orphanedFileDiagnostics:+31
golang.org/x/tools/gopls/internal/cache.(*Session).OrphanedFileDiagnostics:+50
golang.org/x/tools/gopls/internal/server.(*server).diagnoseChangedViews:+54
golang.org/x/tools/gopls/internal/server.(*server).didModifyFiles.func2:+1
runtime.goexit:+0

golang.org/x/tools/gopls@v0.15.1 devel linux/amd64 coc.nvim (4)

Issue created by golang.org/x/tools/gopls/internal/telemetry/cmd/stacks.

[findleyr]

We're not going to be able to fix this until we have crash reporting again (broken in v0.16.2). Maybe we'll get signal from the v0.17.0 prerelease, but I'll plan this for v0.18.0.

[adonovan]

We haven't seen a peep out of this one for months. Perhaps it was fixed by accident, or took on a new guise. Either way, closing.