x/tools/gopls: CodeActions: nil panic in refactorRewriteEliminateDotImport

[adonovan]

#!stacks
"sigpanic" && "types.(*PkgName).Imported" && "refactorRewriteEliminateDotImport:+17"

Issue created by stacks.

This stack LT-h9Q was reported by telemetry:

• crash/crash
• runtime.gopanic:+69,+0x167
• runtime.panicmem:=262,+0x358
• runtime.sigpanic:+19,+0x328
• go/types.(*PkgName).Imported:=258,+0x112
• golang.org/x/tools/gopls/internal/golang.refactorRewriteEliminateDotImport:+17,+0xc0
• golang.org/x/tools/gopls/internal/golang.CodeActions:+64,+0x624
• golang.org/x/tools/gopls/internal/server.(*server).CodeAction:+154,+0x5a8
• golang.org/x/tools/gopls/internal/protocol.serverDispatch:+160,+0x239c
• golang.org/x/tools/gopls/internal/lsprpc.(*streamServer).ServeStream.ServerHandler.func4:+5,+0x84
• golang.org/x/tools/gopls/internal/lsprpc.(*streamServer).ServeStream.handshaker.func5:+52,+0x908
• golang.org/x/tools/gopls/internal/protocol.Handlers.MustReplyHandler.func1:+2,+0xc5
• golang.org/x/tools/gopls/internal/protocol.Handlers.AsyncHandler.func2.2:+3,+0x95
• runtime.goexit:+0,+0x0

golang.org/x/tools/gopls@v0.19.1 go1.24.4 linux/amd64 vscode (1)

Dups: XDE2Zg kVunHQ dRDhIw n5J2wg

[adonovan]

This stack XDE2Zg was reported by telemetry:

• crash/crash
• runtime.gopanic:+69,+0x167
• runtime.panicmem:=262,+0x197
• runtime.sigpanic:+9,+0x167
• go/types.(*PkgName).Imported:=258,+0x112
• golang.org/x/tools/gopls/internal/golang.refactorRewriteEliminateDotImport:+17,+0xc0
• golang.org/x/tools/gopls/internal/golang.CodeActions:+64,+0x624
• golang.org/x/tools/gopls/internal/server.(*server).CodeAction:+154,+0x5a8
• golang.org/x/tools/gopls/internal/protocol.serverDispatch:+160,+0x239c
• golang.org/x/tools/gopls/internal/lsprpc.(*streamServer).ServeStream.ServerHandler.func4:+5,+0x84
• golang.org/x/tools/gopls/internal/lsprpc.(*streamServer).ServeStream.handshaker.func5:+52,+0x908
• golang.org/x/tools/gopls/internal/protocol.Handlers.MustReplyHandler.func1:+2,+0xc5
• golang.org/x/tools/gopls/internal/protocol.Handlers.AsyncHandler.func2.2:+3,+0x95
• runtime.goexit:+0,+0x0

golang.org/x/tools/gopls@v0.19.1 go1.24.4 windows/amd64 other (1)

[adonovan]

This stack kVunHQ was reported by telemetry:

• crash/crash
• runtime.gopanic:+69,+0x153
• runtime.panicmem:=262,+0x2ff
• runtime.sigpanic:+19,+0x2cc
• go/types.(*PkgName).Imported:=258,+0x120
• golang.org/x/tools/gopls/internal/golang.refactorRewriteEliminateDotImport:+17,+0xcc
• golang.org/x/tools/gopls/internal/golang.CodeActions:+64,+0x51b
• golang.org/x/tools/gopls/internal/server.(*server).CodeAction:+154,+0x3ff
• golang.org/x/tools/gopls/internal/protocol.serverDispatch:+160,+0x1d9f
• golang.org/x/tools/gopls/internal/lsprpc.(*StreamServer).ServeStream.ServerHandler.func4:+5,+0x73
• golang.org/x/tools/gopls/internal/lsprpc.(*StreamServer).ServeStream.handshaker.func5:+52,+0x68f
• golang.org/x/tools/gopls/internal/protocol.Handlers.MustReplyHandler.func1:+2,+0xbf
• golang.org/x/tools/gopls/internal/protocol.Handlers.AsyncHandler.func2.2:+3,+0x8f
• runtime.goexit:+0,+0x3

golang.org/x/tools/gopls@v0.20.0 go1.24.5 darwin/arm64 other,vscode (1)

[adonovan]

This stack dRDhIw was reported by telemetry:

• crash/crash
• runtime.gopanic:+69,+0x14f
• runtime.panicmem:=262,+0x2e7
• runtime.sigpanic:+19,+0x2b8
• go/types.(*PkgName).Imported:=258,+0x108
• golang.org/x/tools/gopls/internal/golang.refactorRewriteEliminateDotImport:+17,+0xc0
• golang.org/x/tools/gopls/internal/golang.CodeActions:+64,+0x4d3
• golang.org/x/tools/gopls/internal/server.(*server).CodeAction:+154,+0x3c3
• golang.org/x/tools/gopls/internal/protocol.serverDispatch:+160,+0x1bb7
• golang.org/x/tools/gopls/internal/lsprpc.(*StreamServer).ServeStream.ServerHandler.func4:+5,+0x6f
• golang.org/x/tools/gopls/internal/lsprpc.(*StreamServer).ServeStream.handshaker.func5:+52,+0x637
• golang.org/x/tools/gopls/internal/protocol.Handlers.MustReplyHandler.func1:+2,+0xb3
• golang.org/x/tools/gopls/internal/protocol.Handlers.AsyncHandler.func2.2:+3,+0x7f
• runtime.goexit:+0,+0x3

golang.org/x/tools/gopls@v0.20.0 go1.25.0 darwin/arm64 other (5)