tree 00a10b4a7046def0fa69ee67d5db4f80923c62b8
parent bf6c7f26e9f0fea5b256f9ef6968435dddc5be25
author Matthew Dempsky <mdempsky@google.com> 1629487765 -0700
committer Matthew Dempsky <mdempsky@google.com> 1629494870 +0000

gopls/internal/regtest/codelens: avoid compiler bug

Because of how the compiler internally represents variable references,
it sometimes gets position information incorrectly for them. The
codelens test hits this issue because for

	var x string
	fmt.Println(x)

the diagnostic about "x" escaping to heap (which actually refers to
the implicit conversion to "interface{}" type) should be rightly
reported at the "x" identifier within the call arguments list.
However, due to the aforementioned compiler bug, historically we
reported the diagnostic at the "(" token instead.

In -G=3 mode, the compiler (correctly) report the diagnostic at "x"
instead; but with GOEXPERIMENT=unified, the compiler intentionally
matches the original -G=0 behavior and continues reporting at "("
instead.

This CL avoids the issue entirely by changing the line to
"fmt.Println(42)", which avoids the issue because the compiler always
correctly prints the diagnostic then at "42".

Change-Id: I22d4c756ae801489f3f16c440e4339bc9b115fb0
Reviewed-on: https://go-review.googlesource.com/c/tools/+/343875
Trust: Matthew Dempsky <mdempsky@google.com>
Run-TryBot: Matthew Dempsky <mdempsky@google.com>
gopls-CI: kokoro <noreply+kokoro@google.com>
TryBot-Result: Go Bot <gobot@golang.org>
Reviewed-by: Heschi Kreinick <heschi@google.com>