Add a whitespace munger

Strips all trailing whitespace from non-preformatted blocks

cmd/mungedocs/whitespace_test.go

@@ -0,0 +1,45 @@
+/*
+Copyright 2015 The Kubernetes Authors All rights reserved.
+
+Licensed under the Apache License, Version 2.0 (the "License");
+you may not use this file except in compliance with the License.
+You may obtain a copy of the License at
+
+    http://www.apache.org/licenses/LICENSE-2.0
+
+Unless required by applicable law or agreed to in writing, software
+distributed under the License is distributed on an "AS IS" BASIS,
+WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+See the License for the specific language governing permissions and
+limitations under the License.
+*/
+
+package main
+
+import (
+	"testing"
+
+	"github.com/stretchr/testify/assert"
+)
+
+func Test_updateWhiteSpace(t *testing.T) {
+	var cases = []struct {
+		in       string
+		expected string
+	}{
+		{"", ""},
+		{"\n", "\n"},
+		{"  \t   \t \n", "\n"},
+		{"bob  \t", "bob"},
+		{"```\n   \n```\n", "```\n   \n```\n"},
+	}
+	for i, c := range cases {
+		in := getMungeLines(c.in)
+		expected := getMungeLines(c.expected)
+		actual, err := updateWhitespace("filename.md", in)
+		assert.NoError(t, err)
+		if !expected.Equal(actual) {
+			t.Errorf("Case[%d] Expected Whitespace '%v' but got '%v'", i, string(expected.Bytes()), string(actual.Bytes()))
+		}
+	}
+}