x/tools/gopls: iferr completion content should adjust according to return type of function in scope

[chiawendt]

gopls version

golang.org/x/tools/gopls v0.14.2 golang.org/x/tools/gopls@v0.14.2 h1:sIw6vjZiuQ9S7s0auUUkHlWgsCkKZFWDHmrge8LYsnc= github.com/BurntSushi/toml@v1.2.1 h1:9F2/+DoOYIOksmaJFPw1tGFy1eDnIJXg+UHjuD8lTak= github.com/google/go-cmp@v0.5.9 h1:O2Tfq5qg4qc4AmwVlvv0oLiVAGB7enBSJ2x2DqQFi38= github.com/sergi/go-diff@v1.1.0 h1:we8PVUC3FE2uYfodKH/nBHMSetSfHDR6scGdBi+erh0= golang.org/x/exp/typeparams@v0.0.0-20221212164502-fae10dda9338 h1:2O2DON6y3XMJiQRAS1UWU+54aec2uopH3x7MAiqGW6Y= golang.org/x/mod@v0.14.0 h1:dGoOF9QVLYng8IHTm7BAyWqCqSheQ5pYWGhzW00YJr0= golang.org/x/sync@v0.4.0 h1:zxkM55ReGkDlKSM+Fu41A+zmbZuaPVbGMzvvdUPznYQ= golang.org/x/sys@v0.14.0 h1:Vz7Qs629MkJkGyHxUlRHizWJRG2j8fbQKjELVSNhy7Q= golang.org/x/telemetry@v0.0.0-20231114163143-69313e640400 h1:brbkEFfGwNGAEkykUOcryE/JiHUMMJouzE0fWWmz/QU= golang.org/x/text@v0.13.0 h1:ablQoSUd0tRdKxZewP80B+BaqeKJuVhuRxj/dkrun3k= golang.org/x/tools@v0.14.1-0.20231114185516-c9d3e7de13fd h1:Oku7E+OCrXHyst1dG1z10etCTxewCHXNFLRlyMPbh3w= golang.org/x/vuln@v1.0.1 h1:KUas02EjQK5LTuIx1OylBQdKKZ9jeugs+HiqO5HormU= honnef.co/go/tools@v0.4.5 h1:YGD4H+SuIOOqsyoLOpZDWcieM28W47/zRO7f+9V3nvo= mvdan.cc/gofumpt@v0.4.0 h1:JVf4NN1mIpHogBj7ABpgOyZc65/UUOkKQFkoURsz4MM= mvdan.cc/xurls/v2@v2.4.0 h1:tzxjVAj+wSBmDcF6zBB7/myTy3gX9xvi8Tyr28AuQgc= go: go1.21.6

go env

.

What did you do?

Accept iferr completion in a function of type func() error

What did you see happen?

Completes to
if err != nil { return nil, err }

What did you expect to see?

Completes to if err != nil { return err }

Editor and settings

No response

Logs

No response

[hyangah]

Are you using VS Code Go extension?

If so, it's likely this is coming from the vscode go extension side
https://github.com/golang/vscode-go/blob/0b3fabc4c832194f59ca913f36f048aecd1f78ae/extension/snippets/go.json#L114.
This adds one more reason to deprecate this legacy snippet (golang/vscode-go#160)

For example, this screenshot is the sign that this completion comes from vscode-go side snippets.

[chiawendt]

Yes I am using VS Code Go extension

[suzmue]

There is a similar feature in gopls, postfix completion https://go.dev/issue/64178. It can be triggered by typing . after a variable of an error type (for example err.). It is return value aware and fills in the non-error return values as well, leaving the cursor where the returned error value will be.

This feature could be modified to work without the postfix, so will leave this open as a feature request for that.

[tttoad]

Hi @suzmue , I'm interested in this feature, but I'm working with neovim. Is there an example or documentation on how to call this function? I just need to know how to call it by gopls, thank you.