preformat checker

cmd/mungedocs/preformatted.go

@@ -0,0 +1,57 @@
+/*
+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 (
+	"bytes"
+)
+
+// Blocks of ``` need to have blank lines on both sides or they don't look
+// right in HTML.
+func checkPreformatted(filePath string, fileBytes []byte) ([]byte, error) {
+	f := splitByPreformatted(fileBytes)
+	f = append(fileBlocks{{false, []byte{}}}, f...)
+	f = append(f, fileBlock{false, []byte{}})
+
+	output := []byte(nil)
+	for i := 1; i < len(f)-1; i++ {
+		prev := &f[i-1]
+		block := &f[i]
+		next := &f[i+1]
+		if !block.preformatted {
+			continue
+		}
+		neededSuffix := []byte("\n\n")
+		for !bytes.HasSuffix(prev.data, neededSuffix) {
+			prev.data = append(prev.data, '\n')
+		}
+		for !bytes.HasSuffix(block.data, neededSuffix) {
+			block.data = append(block.data, '\n')
+			if bytes.HasPrefix(next.data, []byte("\n")) {
+				// don't change the number of newlines unless needed.
+				next.data = next.data[1:]
+				if len(next.data) == 0 {
+					f = append(f[:i+1], f[i+2:]...)
+				}
+			}
+		}
+	}
+	for _, block := range f {
+		output = append(output, block.data...)
+	}
+	return output, nil
+}