1 files changed, 41 insertions, 0 deletions
diff --git a/src/cmd/fix/iocopyn.go b/src/cmd/fix/iocopyn.go
new file mode 100644
index 000000000..720f3c689
--- /dev/null
+++ b/src/cmd/fix/iocopyn.go
@@ -0,0 +1,41 @@
+// Copyright 2011 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(ioCopyNFix)
+}
+
+var ioCopyNFix = fix{
+	"iocopyn",
+	"2011-09-30",
+	ioCopyN,
+	`Rename io.Copyn to io.CopyN.
+
+http://codereview.appspot.com/5157045
+`,
+}
+
+func ioCopyN(f *ast.File) bool {
+	if !imports(f, "io") {
+		return false
+	}
+
+	fixed := false
+	walk(f, func(n interface{}) {
+		if expr, ok := n.(ast.Expr); ok {
+			if isPkgDot(expr, "io", "Copyn") {
+				expr.(*ast.SelectorExpr).Sel.Name = "CopyN"
+				fixed = true
+				return
+			}
+		}
+	})
+	return fixed
+}