shouldDeclareErrInSignature: Add note about variable declaration line

When I was first coming up with ideas for the project, I thought that
this line is one I might need to report a diagnostic for, but since the
compiler will catch it, we don't need to bother.

1 files changed, 4 insertions, 1 deletions

diff --git a/testdata/signature.go b/testdata/signature.go
index cc9d72b..d6697c4 100644
--- a/testdata/signature.go
+++ b/testdata/signature.go
@@ -3,7 +3,10 @@ package main
 import "errors"
 
 func shouldDeclareErrInSignature() error { // want "return signature should use named error parameter err"
-	var err error // Should use variable declared in signature
+	// Should use variable declared in signature. We don't need to report this
+	// as if the variable is declared in the signature, a redeclaration causes
+	// a compile error.
+	var err error
 
 	err = nil
 	if err != nil {