x/tools/gopls: panic in completion.enclosingFunction

[jinggangnanyou]

gopls version: v0.7.3
gopls flags:
update flags: proxy
extension version: 2021.10.2813
go version: 1.16.9
environment: Visual Studio Code linux
initialization error: undefined
issue timestamp: Mon, 01 Nov 2021 09:01:20 GMT
restart history:
Mon, 01 Nov 2021 07:28:07 GMT: activation (enabled: true)

ATTENTION: PLEASE PROVIDE THE DETAILS REQUESTED BELOW.

Describe what you observed.

panic: interface conversion: types.Type is *types.Basic, not *types.Signature

goroutine 137 [running]:
golang.org/x/tools/internal/lsp/source/completion.enclosingFunction(0xc007332c00, 0x9, 0x10, 0xc00ad5cf50, 0x0)
	  completion.go:1698  0x350
golang.org/x/tools/internal/lsp/source/completion.Completion(0x10beb38, 0xc00ad66990, 0x10d2ab8, 0xc00aa22000, 0x10c2a38, 0xc00aa4d1a0, 0xe0000000b, 0x3ff0000000000000, 0x0, 0x0, ...)
	  completion.go:508  0x8e6
golang.org/x/tools/internal/lsp.(*Server).completion(0xc000770900, 0x10beb38, 0xc00043a080, 0xc00ad5cdc0, 0x0, 0x0, 0x0)
	  completion.go:32  0xf7a
golang.org/x/tools/internal/lsp.(*Server).Completion(0xc000770900, 0x10beb38, 0xc00043a080, 0xc00ad5cdc0, 0xc00ad5cdc0, 0x0, 0x0)
	  server_gen.go:32  0x49
golang.org/x/tools/internal/lsp/protocol.serverDispatch(0x10beb38, 0xc00043a080, 0x10d5fa0, 0xc000770900, 0xc00ad66630, 0x10beda0, 0xc00043a000, 0x0, 0x0, 0x10ad180)
	  tsserver.go:382  0x2784
golang.org/x/tools/internal/lsp/protocol.ServerHandler.func1(0x10beb38, 0xc00043a080, 0xc00ad66630, 0x10beda0, 0xc00043a000, 0x0, 0xc0580913dbbb4300)
	  protocol.go:154  0xc5
golang.org/x/tools/internal/lsp/lsprpc.handshaker.func1(0x10beb38, 0xc00043a080, 0xc00ad66630, 0x10beda0, 0xc00043a000, 0x0, 0x0)
	  lsprpc.go:506  0x459
golang.org/x/tools/internal/jsonrpc2.MustReplyHandler.func1(0x10beb38, 0xc00043a080, 0xc00043e180, 0x10beda0, 0xc00043a000, 0xb8ef95b8ef94b8ef, 0xefb0b8ef99b8ef96)
	  handler.go:35  0xd7
golang.org/x/tools/internal/jsonrpc2.AsyncHandler.func1.2(0xc000038f60, 0xc000434930, 0xc000114d40, 0x10beb38, 0xc00043a080, 0xc00043e180, 0x10beda0, 0xc00043a000)
	  handler.go:103  0x86
created by golang.org/x/tools/internal/jsonrpc2.AsyncHandler.func1
	  handler.go:100  0x173
[Error - 5:01:03 PM] 

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[findleyr]

It's generally an invariant that functions have *Signature type, concerning that it was violated here. I wonder if our AST mangling went wrong.

Nevertheless, we can make that code more defensive.

[gopherbot]

Change https://golang.org/cl/364675 mentions this issue: internal/lsp/source/completion: avoid invalid AST in enclosingSignature

[findleyr]

This should be fixed at tip.