feat: normalize output and fix some bugs

JayceChant · JayceChant · commit 8c9376fdd0b8 · 2018-05-29T13:57:36.000+08:00
diff --git a/commit-msg.go b/commit-msg.go
@@ -15,37 +15,125 @@ const (
 	BODY_REQUIRED  = false
 )
 
+type MsgState int
+
+const (
+	// normal state
+	Validated MsgState = iota
+	Merge
+	// non format error
+	ArgumentMissing
+	FileMissing
+	ReadError
+	// format error
+	EmptyMessage
+	EmptyHeader
+	BadHeaderFormat
+	WrongType
+	BodyMissing
+	NoBlankLineBeforeBody
+	LineOverLong
+	UndefindedError
+)
+
 var (
+	msgStates = [...]string{
+		"Validated",
+		"Merge",
+		"ArgumentMissing",
+		"FileMissing",
+		"ReadError",
+		"EmptyMessage",
+		"EmptyHeader",
+		"BadHeaderFormat",
+		"WrongType",
+		"BodyMissing",
+		"NoBlankLineBeforeBody",
+		"LineOverLong",
+		"UndefindedError",
+	}
+	stateHint = [...]string{
+		"%s: commit message meet the rule.\n",
+		"%s: merge commit detected，skip check.\n",
+		"Error %s: commit message file argument missing.\n",
+		"Error %s: file %s not exists.\n",
+		"Error %s: read file %s error.\n",
+		"Error %s: commit message has no content except whitespaces.\n",
+		"Error %s: header (first line) has no content except whitespaces.\n",
+		`Error %s: header (first line) not following the rule:
+%s
+if you can not find any error after check, maybe you use Chinese colon, or lack of whitespace after the colon.`,
+		"Error %s: %s, should be one of the keywords:\n%s\n",
+		"Error %s: body has no content except whitespaces.\n",
+		"Error %s: no empty line between header and body.\n",
+		"Error %s: the length of line is %d, exceed %d:\n%s\n",
+		"Error %s: unexpected error occurs, please raise an issue.",
+	}
 	typeList = [...]string{
-		"feat",     // 新功能（feature）
-		"fix",      // 修补bug
-		"docs",     // 文档（documentation）
-		"style",    // 格式（不影响代码运行的变动）
+		"feat",     // new feature 新功能
+		"fix",      // fix bug 修复
+		"docs",     // documentation 文档
+		"style",    // changes not affect logic 格式（不影响代码运行的变动）
 		"refactor", // 重构（既不是新增功能，也不是修改bug的代码变动）
-		"perf",     // 提升性能（performance）
+		"perf",     // performance 提升性能
 		"test",     // 增加测试
 		"chore",    // 构建过程或辅助工具的变动'
 		"revert",   // 撤销以前的 commit
-		"Revert"}   // 有些版本的工具生成的revert message首字母大写
+		"Revert",   // 有些工具生成的 revert 首字母大写
+	}
+	ruleHint = `Commit message rule as follow:
+<type>(<scope>): <subject>
+// empty line
+<body>
+// empty line
+<footer>
+
+(<scope>), <body> and <footer> are optional
+<type>  must be one of %s
+more specific instructions, please refer to https://github.com/JayceChant/commit-msg.go`
 )
 
+func (state MsgState) Name() string {
+	return msgStates[state]
+}
+
+func (state MsgState) Hint() string {
+	return stateHint[state]
+}
+
+func logAndExit(state MsgState, v ...interface{}) {
+	a := append([]interface{}{state.Name()}, v...)
+	if state <= Merge {
+		log.Printf(state.Hint(), a...)
+		os.Exit(0)
+	} else if state <= FileMissing {
+		log.Fatalf(state.Hint(), a...)
+	} else {
+		log.Printf(state.Hint(), a...)
+		log.Fatalf(ruleHint, strings.Join(typeList[:], ", "))
+	}
+}
+
 func getMsg(path string) string {
 	if path == "" {
-		log.Fatalln("Arg missing.")
+		logAndExit(ArgumentMissing)
 	}
 
 	f, err := os.Stat(path)
 	if err != nil {
-		log.Fatalln(err)
+		log.Println(err)
+		logAndExit(FileMissing, path)
 	}
 
 	if f.IsDir() {
-		log.Fatalln(path, "is not a file.")
+		log.Println(path, "is not a file.")
+		logAndExit(FileMissing, path)
 	}
 
 	buf, err := ioutil.ReadFile(path)
 	if err != nil {
-		log.Fatalln(err)
+		log.Println(err)
+		logAndExit(ReadError, path)
 	}
 
 	return string(buf)
@@ -61,64 +149,69 @@ func checkType(type_ string) {
 			return
 		}
 	}
-	log.Fatalln("Wrong type.")
+	logAndExit(WrongType, type_, strings.Join(typeList[:], ", "))
 }
 
 func checkHeader(header string) {
 	if checkEmpty(header) {
-		log.Fatalln("Empty header.")
+		logAndExit(EmptyHeader)
 	}
 
 	re := regexp.MustCompile(HEADER_PATTERN)
 	groups := re.FindStringSubmatch(header)
 
-	isFixupOrSquash := (groups[2] != "")
+	if groups == nil || checkEmpty(groups[5]) {
+		logAndExit(BadHeaderFormat, header)
+	}
 
 	type_ := groups[3]
-	// scope = groups[4] // TODO: 根据配置对scope检查
-	// subject = (groups[5] != "") // TODO: 根据规则对subject检查
 	checkType(type_)
 
+	isFixupOrSquash := (groups[2] != "")
+	// scope := groups[4] // TODO: 根据配置对scope检查
+	// subject := groups[5] // TODO: 根据规则对subject检查
+
 	length := len(header)
-	if length > LINE_LIMIT && !(isFixupOrSquash || type_ == "revert") {
-		log.Fatalln("Line overlong.")
+	if length > LINE_LIMIT &&
+		!(isFixupOrSquash || type_ == "revert" || type_ == "Revert") {
+		logAndExit(LineOverLong, length, LINE_LIMIT, header)
 	}
 }
 
 func checkBody(body string) {
 	if checkEmpty(body) {
 		if BODY_REQUIRED {
-			log.Fatalln("Empty body.")
+			logAndExit(BodyMissing)
 		} else {
-			return
+			logAndExit(Validated)
 		}
 	}
 
 	if !checkEmpty(strings.SplitN(body, "\n", 2)[0]) {
-		log.Fatalln("Blank line lacking between header and body.")
+		logAndExit(NoBlankLineBeforeBody)
 	}
 
 	for _, line := range strings.Split(body, "\n") {
-		if len(line) > LINE_LIMIT {
-			log.Fatalln("Line overlong.")
+		length := len(line)
+		if length > LINE_LIMIT {
+			logAndExit(LineOverLong, length, LINE_LIMIT, line)
 		}
 	}
 }
 
 func validateMsg(msg string) {
-	msg = strings.TrimSpace(msg)
-	if msg == "" {
-		log.Fatalln("Empty Message.")
+	if checkEmpty(msg) {
+		logAndExit(EmptyMessage)
 	}
 
 	isMerge, err := regexp.MatchString(MERGE_PATTERN, msg)
 	if err != nil {
-		log.Fatalln(err)
+		log.Println(err)
+		logAndExit(UndefindedError)
 	}
 
 	if isMerge {
-		log.Println("Merge message, skip check.")
-		os.Exit(0)
+		logAndExit(Merge)
 	}
 
 	sections := strings.SplitN(msg, "\n", 2)
@@ -127,8 +220,10 @@ func validateMsg(msg string) {
 	if len(sections) == 2 {
 		checkBody(sections[1])
 	} else if BODY_REQUIRED {
-		log.Fatalln("Body missing. Maybe a new line is lacking.")
+		logAndExit(BodyMissing)
 	}
+
+	logAndExit(Validated)
 }
 
 func main() {
