Panic when transforming optional chaining with define

[hi-ogawa]

Esbuild panics when transforming globalThis.process?.env.something with { define: { "globalThis.process.env": "{}" } } and this seems to be the cause of the issue on Vite vitejs/vite#15367.

Here is a playground link for a minimal repro:

• Playground Link

I'm not sure what's the expected behavior (whether replace it or not since they don't exactly match syntactically), but I suppose panic is not expected to happen regardless.

[hi-ogawa]

It looks like OptionalChainContinue case seems tricky:

esbuild/internal/js_ast/js_ast.go

Lines 583 to 585 in b76b54f

	// "a?.b.c" => ".c" is OptionalChainContinue
	// "(a?.b).c" => ".c" is OptionalChainNone
	OptionalChainContinue

I tested with OptionalChainNone version and actually define is applied for this case without panic:

https://esbuild.github.io/try/#dAAwLjE5LjkAeyBkZWZpbmU6IHsgImEuYiI6ICJ7fSIgfSB9AC8vIHBhbmljCi8vIGE/LmIuYwoKLy8gb2sKKGE/LmIpLmMKCi8vIG9rCi8vIGEuYi5j