x/tools/gopls: documentHighlight from subpackage selects usage for parent package

[borsosl]

What version of Go, VS Code & VS Code Go extension are you using?

Version Information

• Run go version to get version of Go from the VS Code integrated terminal.
  • go version go1.20 windows/amd64
• Run gopls -v version to get version of Gopls from the VS Code integrated terminal.
  • golang.org/x/tools/gopls v0.11.0
• Run code -v or code-insiders -v to get version of VS Code or VS Code Insiders.
  • 1.78.2
  • b3e4e68a0bc097f0ae7907b217c1119af9e03435
  • x64
• Check your installed extensions to get the version of the VS Code Go extension
  • v0.38.0
• Run Ctrl+Shift+P (Cmd+Shift+P on Mac OS) > Go: Locate Configured Go Tools command.
  • gotests: C:\Users\Laci\go\bin\gotests.exe (version: v1.6.0 built with go: go1.20)
    gomodifytags: C:\Users\Laci\go\bin\gomodifytags.exe (version: v1.16.0 built with go: go1.20)
    impl: C:\Users\Laci\go\bin\impl.exe (version: v1.1.0 built with go: go1.20)
    goplay: C:\Users\Laci\go\bin\goplay.exe (version: v1.0.0 built with go: go1.20)
    dlv: C:\Users\Laci\go\bin\dlv.exe (version: v1.20.2 built with go: go1.20)
    staticcheck: C:\Users\Laci\go\bin\staticcheck.exe (version: v0.4.3 built with go: go1.20)
    gopls: C:\Users\Laci\go\bin\gopls.exe (version: v0.11.0 built with go: go1.20)

Share the Go related settings you have added/edited

Run Preferences: Open Settings (JSON) command to open your settings.json file.
Share all the settings with the go. or ["go"] or gopls prefixes.

"go.testFlags": ["-v"],
"gopls": {
    "buildFlags": ["-tags=integration"]
},

Describe the bug

Use a source file that imports both a parent and a subpackage:

import (
...
"net/http"
"net/http/httptest"
...
)

Normally clicking on an imported package and using F7 cycles through its usages. In the case of the subpackage, it also finds the parent package usages.
Expected: Starting from the subpackage import, F7 should cycle through only usages of the subpackage.

Steps to reproduce the behavior:

1. Open a source file that imports both "net/http" and "net/http/httptest" and uses http first
2. Click on 'httptest' within the imports
3. Press F7
4. Observe that the first http usage is selected

Screenshots or recordings

If applicable, add screenshots or recordings to help explain your problem.

[suzmue]

Thanks for the report! I am able to reproduce that the parent package references are selected.

This appears to be an issue with the textDocument/documentHighlight feature in gopls.

Repro case:

main.go:

package main

import (
	"net/http"
	"net/http/httptest"
)

func main() {
	http.CanonicalHeaderKey("")
	httptest.NewRecorder()
}

Log:

[Trace - 12:51:35.785 PM] Sending request 'textDocument/documentHighlight - (15)'.
Params: {"textDocument":{"uri":"file:///Users/suzmue/issue2781/main.go"},"position":{"line":4,"character":15}}


[Trace - 12:51:35.786 PM] Received response 'textDocument/documentHighlight - (15)' in 0ms.
Result: [{"range":{"start":{"line":4,"character":1},"end":{"line":4,"character":20}},"kind":1},{"range":{"start":{"line":8,"character":1},"end":{"line":8,"character":5}},"kind":1},{"range":{"start":{"line":9,"character":1},"end":{"line":9,"character":9}},"kind":1}]

[gopherbot]

Change https://go.dev/cl/498268 mentions this issue: internal/lsp/source: use exact match in import highlighting