go/parser: Use test-specific filesets to avoid races.

Only affects test code.

Fixes #9025.
Fixes #9130.

LGTM=r, adonovan
R=adonovan, r
CC=golang-codereviews
https://golang.org/cl/180920043

1 files changed, 9 insertions, 11 deletions

diff --git a/src/go/parser/parser_test.go b/src/go/parser/parser_test.go
index 85065fd182..51ce1a9337 100644
--- a/src/go/parser/parser_test.go
+++ b/src/go/parser/parser_test.go
@@ -14,8 +14,6 @@ import (
 	"testing"
 )
 
-var fset = token.NewFileSet()
-
 var validFiles = []string{
 	"parser.go",
 	"parser_test.go",
@@ -25,7 +23,7 @@ var validFiles = []string{
 
 func TestParse(t *testing.T) {
 	for _, filename := range validFiles {
-		_, err := ParseFile(fset, filename, nil, DeclarationErrors)
+		_, err := ParseFile(token.NewFileSet(), filename, nil, DeclarationErrors)
 		if err != nil {
 			t.Fatalf("ParseFile(%s): %v", filename, err)
 		}
@@ -46,7 +44,7 @@ func dirFilter(f os.FileInfo) bool { return nameFilter(f.Name()) }
 
 func TestParseDir(t *testing.T) {
 	path := "."
-	pkgs, err := ParseDir(fset, path, dirFilter, 0)
+	pkgs, err := ParseDir(token.NewFileSet(), path, dirFilter, 0)
 	if err != nil {
 		t.Fatalf("ParseDir(%s): %v", path, err)
 	}
@@ -131,7 +129,7 @@ func TestParseExpr(t *testing.T) {
 }
 
 func TestColonEqualsScope(t *testing.T) {
-	f, err := ParseFile(fset, "", `package p; func f() { x, y, z := x, y, z }`, 0)
+	f, err := ParseFile(token.NewFileSet(), "", `package p; func f() { x, y, z := x, y, z }`, 0)
 	if err != nil {
 		t.Fatal(err)
 	}
@@ -153,7 +151,7 @@ func TestColonEqualsScope(t *testing.T) {
 }
 
 func TestVarScope(t *testing.T) {
-	f, err := ParseFile(fset, "", `package p; func f() { var x, y, z = x, y, z }`, 0)
+	f, err := ParseFile(token.NewFileSet(), "", `package p; func f() { var x, y, z = x, y, z }`, 0)
 	if err != nil {
 		t.Fatal(err)
 	}
@@ -183,7 +181,7 @@ var x int
 func f() { L: }
 `
 
-	f, err := ParseFile(fset, "", src, 0)
+	f, err := ParseFile(token.NewFileSet(), "", src, 0)
 	if err != nil {
 		t.Fatal(err)
 	}
@@ -221,7 +219,7 @@ func f() { L: }
 }
 
 func TestUnresolved(t *testing.T) {
-	f, err := ParseFile(fset, "", `
+	f, err := ParseFile(token.NewFileSet(), "", `
 package p
 //
 func f1a(int)
@@ -316,7 +314,7 @@ var imports = map[string]bool{
 func TestImports(t *testing.T) {
 	for path, isValid := range imports {
 		src := fmt.Sprintf("package p; import %s", path)
-		_, err := ParseFile(fset, "", src, 0)
+		_, err := ParseFile(token.NewFileSet(), "", src, 0)
 		switch {
 		case err != nil && isValid:
 			t.Errorf("ParseFile(%s): got %v; expected no error", src, err)
@@ -327,7 +325,7 @@ func TestImports(t *testing.T) {
 }
 
 func TestCommentGroups(t *testing.T) {
-	f, err := ParseFile(fset, "", `
+	f, err := ParseFile(token.NewFileSet(), "", `
 package p /* 1a */ /* 1b */      /* 1c */ // 1d
 /* 2a
 */
@@ -421,7 +419,7 @@ func checkFieldComments(t *testing.T, file *ast.File, fieldname, lead, line stri
 }
 
 func TestLeadAndLineComments(t *testing.T) {
-	f, err := ParseFile(fset, "", `
+	f, err := ParseFile(token.NewFileSet(), "", `
 package p
 type T struct {
 	/* F1 lead comment */