x/tools/gopls: (recovered) panic in canRemoveParameter

[findleyr]

#!stacks
"bug.Errorf" && "go/ast.Walk" && "go/ast.Inspect" && "lsp.canRemoveParameter:22"

Found via telemetry: https://storage.googleapis.com/prod-telemetry-merged/2023-10-25.json

There's a panic in lsp.canRemoveParameter: inspecting nil function bodies (as is the case for external functions) leads to a panic.

Fix incoming.

Dups: vf_9ow, 9eOAKA PymcbA BTt5nw 3W4qPQ

[gopherbot]

Change https://go.dev/cl/537878 mentions this issue: gopls/internal/lsp: fix code action panic on params of external funcs

[gopherbot]

Change https://go.dev/cl/537879 mentions this issue: [gopls-release-branch.0.14] gopls/internal/lsp: fix code action panic on params of external funcs

[adonovan]

This stack 9eOAKA was reported by telemetry:

gopls/bug
golang.org/x/tools/gopls/internal/bug.report:35
golang.org/x/tools/gopls/internal/bug.Errorf:2
golang.org/x/tools/gopls/internal/lsp.refactorRewrite.func1:2
runtime.gopanic:50
runtime.panicmem:?261
runtime.sigpanic:19
go/ast.Walk:184
go/ast.Inspect:?397
golang.org/x/tools/gopls/internal/lsp.canRemoveParameter:22
golang.org/x/tools/gopls/internal/lsp.refactorRewrite:14
golang.org/x/tools/gopls/internal/lsp.(*Server).codeAction:220
golang.org/x/tools/gopls/internal/lsp.(*Server).CodeAction:1
golang.org/x/tools/gopls/internal/lsp/protocol.serverDispatch:142
golang.org/x/tools/gopls/internal/lsp/lsprpc.(*StreamServer).ServeStream.ServerHandler.func3:5
golang.org/x/tools/gopls/internal/lsp/lsprpc.(*StreamServer).ServeStream.handshaker.func4:52
golang.org/x/tools/gopls/internal/lsp/protocol.Handlers.MustReplyHandler.func1:2

golang.org/x/tools/gopls@v0.14.0 go1.22.3 darwin/amd64 vscode (1)

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

[adonovan]

This stack PymcbA was reported by telemetry:

• gopls/bug
• golang.org/x/tools/gopls/internal/bug.report:35
• golang.org/x/tools/gopls/internal/bug.Errorf:2
• golang.org/x/tools/gopls/internal/lsp.refactorRewrite.func1:2
• runtime.gopanic:80
• runtime.panicmem:?260
• runtime.sigpanic:9
• go/ast.Walk:184
• go/ast.Inspect:?397
• golang.org/x/tools/gopls/internal/lsp.canRemoveParameter:22
• golang.org/x/tools/gopls/internal/lsp.refactorRewrite:14
• golang.org/x/tools/gopls/internal/lsp.(*Server).codeAction:220
• golang.org/x/tools/gopls/internal/lsp.(*Server).CodeAction:1
• golang.org/x/tools/gopls/internal/lsp/protocol.serverDispatch:142
• golang.org/x/tools/gopls/internal/lsp/protocol.ServerHandler.func1:5
• golang.org/x/tools/gopls/internal/lsp/lsprpc.handshaker.func1:52
• golang.org/x/tools/internal/jsonrpc2.MustReplyHandler.func1:2

golang.org/x/tools/gopls@v0.14.0 go1.19.3 windows/amd64 other (1)

[adonovan]

This stack BTt5nw was reported by telemetry:

• gopls/bug
• golang.org/x/tools/gopls/internal/bug.report:35
• golang.org/x/tools/gopls/internal/bug.Errorf:2
• golang.org/x/tools/gopls/internal/lsp.refactorRewrite.func1:2
• runtime.gopanic:80
• runtime.panicmem:?260
• runtime.sigpanic:19
• go/ast.Walk:184
• go/ast.Inspect:?397
• golang.org/x/tools/gopls/internal/lsp.canRemoveParameter:22
• golang.org/x/tools/gopls/internal/lsp.refactorRewrite:14
• golang.org/x/tools/gopls/internal/lsp.(*Server).codeAction:220
• golang.org/x/tools/gopls/internal/lsp.(*Server).CodeAction:1
• golang.org/x/tools/gopls/internal/lsp/protocol.serverDispatch:142
• golang.org/x/tools/gopls/internal/lsp/protocol.ServerHandler.func1:5
• golang.org/x/tools/gopls/internal/lsp/lsprpc.handshaker.func1:52
• golang.org/x/tools/internal/jsonrpc2.MustReplyHandler.func1:2

golang.org/x/tools/gopls@v0.14.0 go1.20.14 darwin/amd64 vscode (1)