cmd/fix: Add keys to printer.Config composite literals.

Fixes #4499.

R=rsc
CC=golang-dev
https://golang.org/cl/6931046

diff --git a/src/cmd/fix/printerconfig.go b/src/cmd/fix/printerconfig.go
new file mode 100644 (file)
index 0000000..432e18b
--- /dev/null
+++ b/src/cmd/fix/printerconfig.go
@@ -0,0 +1,61 @@
+// Copyright 2012 The Go Authors.  All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+package main
+
+import "go/ast"
+
+func init() {
+       register(printerconfigFix)
+}
+
+var printerconfigFix = fix{
+       "printerconfig",
+       "2012-12-11",
+       printerconfig,
+       `Add element keys to Config composite literals.`,
+}
+
+func printerconfig(f *ast.File) bool {
+       if !imports(f, "go/printer") {
+               return false
+       }
+
+       fixed := false
+       walk(f, func(n interface{}) {
+               cl, ok := n.(*ast.CompositeLit)
+               if !ok {
+                       return
+               }
+               se, ok := cl.Type.(*ast.SelectorExpr)
+               if !ok {
+                       return
+               }
+               if !isTopName(se.X, "printer") || se.Sel == nil {
+                       return
+               }
+
+               if ss := se.Sel.String(); ss == "Config" {
+                       for i, e := range cl.Elts {
+                               if _, ok := e.(*ast.KeyValueExpr); ok {
+                                       break
+                               }
+                               switch i {
+                               case 0:
+                                       cl.Elts[i] = &ast.KeyValueExpr{
+                                               Key:   ast.NewIdent("Mode"),
+                                               Value: e,
+                                       }
+                               case 1:
+                                       cl.Elts[i] = &ast.KeyValueExpr{
+                                               Key:   ast.NewIdent("Tabwidth"),
+                                               Value: e,
+                                       }
+                               }
+                               fixed = true
+                       }
+               }
+       })
+       return fixed
+}

diff --git a/src/cmd/fix/printerconfig_test.go b/src/cmd/fix/printerconfig_test.go
new file mode 100644 (file)
index 0000000..72e2bdc
--- /dev/null
+++ b/src/cmd/fix/printerconfig_test.go
@@ -0,0 +1,37 @@
+// Copyright 2012 The Go Authors.  All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+package main
+
+func init() {
+       addTestCases(printerconfigTests, printerconfig)
+}
+
+var printerconfigTests = []testCase{
+       {
+               Name: "printerconfig.0",
+               In: `package main
+
+import "go/printer"
+
+func f() printer.Config {
+       b := printer.Config{0, 8}
+       c := &printer.Config{0}
+       d := &printer.Config{Tabwidth: 8, Mode: 0}
+       return printer.Config{0, 8}
+}
+`,
+               Out: `package main
+
+import "go/printer"
+
+func f() printer.Config {
+       b := printer.Config{Mode: 0, Tabwidth: 8}
+       c := &printer.Config{Mode: 0}
+       d := &printer.Config{Tabwidth: 8, Mode: 0}
+       return printer.Config{Mode: 0, Tabwidth: 8}
+}
+`,
+       },
+}