arrow function keywords `async` and `await` crash when hover over

[pedro757]

Stack trace

Don't know where to find this

Steps to reproduce

1. Copy the code below in a file and hover over async or await keywords

async () => {
  await Promise.resolve(true);
}

Additional Context

It doesn't panic with non-arrow-function such as, it works as expected, the problem happens only with async arrow functions

async function() {
  await Promise.resolve(true);
}

[jakebailey]

Can you please show your backtrace? When the error happens, the VS Code popup has a button which takes you to the logs, where you can find the panic.

[pedro757]

Where do I find that ?

@jakebailey

This is the error I get in my editor:

[pedro757]

This is the best I can do at the moment @jakebailey

tsgo: -32603: InternalError: panic handling request textDocument/documentHighlight: interface conversion: ast.nodeData is *ast.ArrowFunction, not *ast.FunctionDeclaration

[jakebailey]

I don't know what editor that is. There is a separate log that comes out of stderr that should be getting captured somewhere.

[pedro757]

neovim

[pedro757]

This could possible be what you are asking for

[ERROR][2025-10-07 11:52:26] /usr/share/nvim/runtime/lua/vim/lsp/log.lua:151	"rpc"	"tsgo"	"stderr"	"panic handling request textDocument/documentHighlight interface conversion: ast.nodeData is *ast.ArrowFunction, not *ast.FunctionDeclaration goroutine 65445 [running]:
runtime/debug.Stack()
	runtime/debug/stack.go:26 +0x5e
github.com/microsoft/typescript-go/internal/lsp.(*Server).recover(0xc000116dc0, 0xc0338e9110)
	github.com/microsoft/typescript-go/internal/lsp/server.go:541 +0x58
panic({0xb349c0?, 0xc0338e9560?})
	runtime/panic.go:783 +0x132
github.com/microsoft/typescript-go/internal/ast.(*Node).AsFunctionDeclaration(...)
	github.com/microsoft/typescript-go/internal/ast/ast.go:1657
github.com/microsoft/typescript-go/internal/ls.getAsyncAndAwaitOccurrences(0x2?, 0x0?)
	github.com/microsoft/typescript-go/internal/ls/documenthighlights.go:557 +0x225
github.com/microsoft/typescript-go/internal/ls.(*LanguageService).getSyntacticDocumentHighlights(0xc0338e9350, 0xe87850?, 0xc06c17ef08)
	github.com/microsoft/typescript-go/internal/ls/documenthighlights.go:136 +0x1d6
github.com/microsoft/typescript-go/internal/ls.(*LanguageService).ProvideDocumentHighlights(0xc0338e9350, {0xe87850, 0xc0330f8000}, {0xc0a4d0f260?, 0x0?}, {0x419b09?, 0x0?})
	github.com/microsoft/typescript-go/internal/ls/documenthighlights.go:47 +0x405
github.com/microsoft/typescript-go/internal/lsp.(*Server).handleDocumentHighlight(0xc0002a4000?, {0xe87850?, 0xc0330f8000?}, 0xc0a4d0f260?, 0x56?)
	github.com/microsoft/typescript-go/internal/lsp/server.go:844 +0x35
github.com/microsoft/typescript-go/internal/lsp.init.func1.registerLanguageServiceDocumentRequestHandler[...].24({0xe87850, 0xc0330f8000}, 0xc0338e9110)
	github.com/microsoft/typescript-go/internal/lsp/server.go:527 +0x11a
github.com/microsoft/typescript-go/internal/lsp.(*Server).handleRequestOrNotification(0xc000116dc0, {0xe87850, 0xc0330f8000}, 0xc0338e9110)
	github.com/microsoft/typescript-go/internal/lsp/server.go:424 +0x10d
github.com/microsoft/typescript-go/internal/lsp.(*Server).dispatchLoop.func1()
	github.com/microsoft/typescript-go/internal/lsp/server.go:329 +0x3a
created by github.com/microsoft/typescript-go/internal/lsp.(*Server).dispatchLoop in goroutine 7
	github.com/microsoft/typescript-go/internal/lsp/server.go:349 +0x8aa

"

@jakebailey

[jakebailey]

Yes, it is. Reformatted.

[jakebailey]

getAsyncAndAwaitOccurrences is incorrectly ported; it does parent.AsFunctionDeclaration() but the original code does getContainingFunction(node) as FunctionLikeDeclaration;, which can be multiple concrete types.