cmd/gofmt: minor internal cleanups

Reflect changes of reflect API.

LGTM=r
R=golang-codereviews, r
CC=golang-codereviews
https://golang.org/cl/69240044

diff --git a/src/cmd/gofmt/rewrite.go b/src/cmd/gofmt/rewrite.go
index 66d2331a5ea595a1e7ef2068f4469f5f85c4a94a..fb6c6fc811af3b98b3397a8bba29c8b8cb5ad515 100644 (file)
--- a/src/cmd/gofmt/rewrite.go
+++ b/src/cmd/gofmt/rewrite.go
@@ -48,7 +48,7 @@ func parseExpr(s, what string) ast.Expr {
 /*
 func dump(msg string, val reflect.Value) {
        fmt.Printf("%s:\n", msg)
-       ast.Print(fset, val.Interface())
+       ast.Print(fileSet, val.Interface())
        fmt.Println()
 }
 */
@@ -59,8 +59,9 @@ func rewriteFile(pattern, replace ast.Expr, p *ast.File) *ast.File {
        m := make(map[string]reflect.Value)
        pat := reflect.ValueOf(pattern)
        repl := reflect.ValueOf(replace)
-       var f func(val reflect.Value) reflect.Value // f is recursive
-       f = func(val reflect.Value) reflect.Value {
+
+       var rewriteVal func(val reflect.Value) reflect.Value
+       rewriteVal = func(val reflect.Value) reflect.Value {
                // don't bother if val is invalid to start with
                if !val.IsValid() {
                        return reflect.Value{}
@@ -68,22 +69,22 @@ func rewriteFile(pattern, replace ast.Expr, p *ast.File) *ast.File {
                for k := range m {
                        delete(m, k)
                }
-               val = apply(f, val)
+               val = apply(rewriteVal, val)
                if match(m, pat, val) {
                        val = subst(m, repl, reflect.ValueOf(val.Interface().(ast.Node).Pos()))
                }
                return val
        }
-       r := apply(f, reflect.ValueOf(p)).Interface().(*ast.File)
+
+       r := apply(rewriteVal, reflect.ValueOf(p)).Interface().(*ast.File)
        r.Comments = cmap.Filter(r).Comments() // recreate comments list
        return r
 }
 
-// setValue is a wrapper for x.SetValue(y); it protects
-// the caller from panics if x cannot be changed to y.
-func setValue(x, y reflect.Value) {
-       // don't bother if y is invalid to start with
-       if !y.IsValid() {
+// set is a wrapper for x.Set(y); it protects the caller from panics if x cannot be changed to y.
+func set(x, y reflect.Value) {
+       // don't bother if x cannot be set or y is invalid
+       if !x.CanSet() || !y.IsValid() {
                return
        }
        defer func() {
@@ -134,16 +135,16 @@ func apply(f func(reflect.Value) reflect.Value, val reflect.Value) reflect.Value
        case reflect.Slice:
                for i := 0; i < v.Len(); i++ {
                        e := v.Index(i)
-                       setValue(e, f(e))
+                       set(e, f(e))
                }
        case reflect.Struct:
                for i := 0; i < v.NumField(); i++ {
                        e := v.Field(i)
-                       setValue(e, f(e))
+                       set(e, f(e))
                }
        case reflect.Interface:
                e := v.Elem()
-               setValue(v, f(e))
+               set(v, f(e))
        }
        return val
 }