go/ast: document invalid comment end positions with CRLF line endings
We've decided that issues like golang/go#41197 are unfixable, so
instead, document the bug.
Fixes golang/go#41197
Change-Id: I5649027f6e2445eec765516f2f642db0d601ea20
Reviewed-on: https://go-review.googlesource.com/c/go/+/270938
Trust: Rebecca Stambler <rstambler@golang.org>
Run-TryBot: Rebecca Stambler <rstambler@golang.org>
Reviewed-by: Robert Griesemer <gri@golang.org>
diff --git a/src/go/ast/ast.go b/src/go/ast/ast.go
index 1061f1d..300966a 100644
--- a/src/go/ast/ast.go
+++ b/src/go/ast/ast.go
@@ -57,6 +57,11 @@
// Comments
// A Comment node represents a single //-style or /*-style comment.
+//
+// The Text field contains the comment text without carriage returns (\r) that
+// may have been present in the source. Because a comment's end position is
+// computed using len(Text), the position reported by End() does not match the
+// true source end position for comments containing carriage returns.
type Comment struct {
Slash token.Pos // position of "/" starting the comment
Text string // comment text (excluding '\n' for //-style comments)
