Refactoring.

Fix unnecessary type conversion.
Fix argument order in diff.
Update to latest go-runewidth.

Author: yushi

Godeps

@@ -9,8 +9,8 @@
 		},
 		{
 			"ImportPath": "github.com/mattn/go-runewidth",
-			"Comment": "go1",
-			"Rev": "ce86f93d9cc06f69ba0441bbe37c8845e0dc9204"
+			"Comment": "travisish-12-g39104c7",
+			"Rev": "39104c78546f11be4bbc161e39858258aac6d9b8"
 		},
 		{
 			"ImportPath": "github.com/russross/blackfriday",

markdown/main.go

@@ -101,10 +101,10 @@ func (_ *markdownRenderer) Header(out *bytes.Buffer, text func() bool, level int
 
 	switch level {
 	case 1:
-		len := runewidth.StringWidth(string(out.Bytes()[textMarker:]))
+		len := runewidth.StringWidth(out.String()[textMarker:])
 		fmt.Fprint(out, "\n", strings.Repeat("=", len))
 	case 2:
-		len := runewidth.StringWidth(string(out.Bytes()[textMarker:]))
+		len := runewidth.StringWidth(out.String()[textMarker:])
 		fmt.Fprint(out, "\n", strings.Repeat("-", len))
 	}
 	out.WriteString("\n")

markdown/main_test.go

@@ -217,7 +217,7 @@ aaa/あああ
 		log.Fatalln(err)
 	}
 
-	diff, err := diff(output, expected)
+	diff, err := diff(expected, output)
 	if err != nil {
 		log.Fatalln(err)
 	}