From: Shenghou Ma <minux@golang.org>
Date: Fri, 25 Oct 2019 01:29:30 +0000 (-0400)
Subject: cmd/compile/internal/gc: reword "declared and not used" error message
X-Git-Tag: go1.14beta1~528
X-Git-Url: http://www.git.cypherpunks.su/?a=commitdiff_plain;h=449b6abbacc464443a7faf166bf4db3df3e0f8da;p=gostls13.git

cmd/compile/internal/gc: reword "declared and not used" error message

"declared and not used" is technically correct, but might confuse
the user. Switching "and" to "but" will hopefully create the
contrast for the users: they did one thing (declaration), but
not the other --- actually using the variable.

This new message is still not ideal (specifically, declared is not
entirely precise here), but at least it matches the other parsers
and is one step in the right direction.

Change-Id: I725c7c663535f9ab9725c4b0bf35b4fa74b0eb20
Reviewed-on: https://go-review.googlesource.com/c/go/+/203282
Run-TryBot: Minux Ma <minux@golang.org>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Robert Griesemer <gri@golang.org>
Reviewed-by: Matthew Dempsky <mdempsky@google.com>
---

diff --git a/src/cmd/compile/internal/gc/swt.go b/src/cmd/compile/internal/gc/swt.go
index 2970993056..0d5df2e0bd 100644
--- a/src/cmd/compile/internal/gc/swt.go
+++ b/src/cmd/compile/internal/gc/swt.go
@@ -32,7 +32,7 @@ func typecheckTypeSwitch(n *Node) {
 	// declaration itself. So if there are no cases, we won't
 	// notice that it went unused.
 	if v := n.Left.Left; v != nil && !v.isBlank() && n.List.Len() == 0 {
-		yyerrorl(v.Pos, "%v declared and not used", v.Sym)
+		yyerrorl(v.Pos, "%v declared but not used", v.Sym)
 	}
 
 	var defCase, nilCase *Node
diff --git a/src/cmd/compile/internal/gc/walk.go b/src/cmd/compile/internal/gc/walk.go
index 7d9f0cbd58..0e780bad6c 100644
--- a/src/cmd/compile/internal/gc/walk.go
+++ b/src/cmd/compile/internal/gc/walk.go
@@ -50,10 +50,10 @@ func walk(fn *Node) {
 			if defn.Left.Name.Used() {
 				continue
 			}
-			yyerrorl(defn.Left.Pos, "%v declared and not used", ln.Sym)
+			yyerrorl(defn.Left.Pos, "%v declared but not used", ln.Sym)
 			defn.Left.Name.SetUsed(true) // suppress repeats
 		} else {
-			yyerrorl(ln.Pos, "%v declared and not used", ln.Sym)
+			yyerrorl(ln.Pos, "%v declared but not used", ln.Sym)
 		}
 	}
 
diff --git a/test/fixedbugs/bug373.go b/test/fixedbugs/bug373.go
index aa0f5d1efa..6b7a312097 100644
--- a/test/fixedbugs/bug373.go
+++ b/test/fixedbugs/bug373.go
@@ -9,7 +9,7 @@
 package foo
 
 func f(x interface{}) {
-	switch t := x.(type) {  // ERROR "declared and not used"
+	switch t := x.(type) {  // ERROR "declared but not used"
 	case int:
 	}
 }
diff --git a/test/fixedbugs/issue21317.go b/test/fixedbugs/issue21317.go
index 530694af12..ee1bbf810b 100644
--- a/test/fixedbugs/issue21317.go
+++ b/test/fixedbugs/issue21317.go
@@ -48,8 +48,8 @@ func main() {
 		log.Fatalf("expected cmd/compile to fail")
 	}
 	wantErrs := []string{
-		"7:9: n declared and not used",
-		"7:12: err declared and not used",
+		"7:9: n declared but not used",
+		"7:12: err declared but not used",
 	}
 	outStr := string(out)
 	for _, want := range wantErrs {
diff --git a/test/fixedbugs/issue23116.go b/test/fixedbugs/issue23116.go
index 1737fee2c8..b4b36d4ba9 100644
--- a/test/fixedbugs/issue23116.go
+++ b/test/fixedbugs/issue23116.go
@@ -10,6 +10,6 @@ func f(x interface{}) {
 	switch x.(type) {
 	}
 
-	switch t := x.(type) { // ERROR "declared and not used"
+	switch t := x.(type) { // ERROR "declared but not used"
 	}
 }
diff --git a/test/fixedbugs/issue29870b.go b/test/fixedbugs/issue29870b.go
index 1bac566bbb..2d5f638530 100644
--- a/test/fixedbugs/issue29870b.go
+++ b/test/fixedbugs/issue29870b.go
@@ -10,5 +10,5 @@
 package main
 
 func _() {
-	x := 7 // ERROR "x declared and not used"
+	x := 7 // ERROR "x declared but not used"
 }
diff --git a/test/typeswitch2b.go b/test/typeswitch2b.go
index 135ae86cff..6da0d5fa6e 100644
--- a/test/typeswitch2b.go
+++ b/test/typeswitch2b.go
@@ -11,9 +11,9 @@ package main
 
 func notused(x interface{}) {
 	// The first t is in a different scope than the 2nd t; it cannot
-	// be accessed (=> declared and not used error); but it is legal
+	// be accessed (=> declared but not used error); but it is legal
 	// to declare it.
-	switch t := 0; t := x.(type) { // ERROR "declared and not used"
+	switch t := 0; t := x.(type) { // ERROR "declared but not used"
 	case int:
 		_ = t // this is using the t of "t := x.(type)"
 	}