x/tools/gopls: missing unimported package candidates

[muirdm]

Repro (assuming completeUnimported=true is configured):

1. Create a new module with contents:

package main

func main() {
}

1. Complete rand.. You should see suggestions from crypto/rand and math/rand.
2. Select rand.Int from "crypto/rand"
3. Delete line and save ("crypto/rand" import should disappear).
4. Wait a second to make sure "crypto/rand" package handle gets GC'd 😉
5. Complete rand. again. Now you only see untyped completions from "crypto/rand". I expected to see typed completions from "crypto/rand" and completions from "math/rand".

See https://youtu.be/VaOs1crVI4g

/cc @stamblerre @heschik

[gopherbot]

Thank you for filing a gopls issue! Please take a look at the Troubleshooting guide, and make sure that you have provided all of the relevant information here.

[heschi]

When I look at logs, I see a ton of "no file for" errors, which are coming from findFileInPackage in pkg.go. Will look tomorrow.

[heschi]

...I looked a little now. The problem is that findFileInPackage can't find anything for math/rand/rand.go because it's not in the package's dependencies any more. Annoying, since I had the package to start with when I called packageMembers.

[gopherbot]

Change https://golang.org/cl/205501 mentions this issue: internal/lsp/source: attach Package to completions when available

[gopherbot]

Change https://golang.org/cl/205658 mentions this issue: internal/lsp/source: attach Package to completions when available