refactor: linter errors, common handling for rules

Author: muthukrishnan24

config/config.go

@@ -52,7 +52,7 @@ func Parse(confPath string) (*lint.Config, error) {
 // Validate validates given config instance, it checks the following
 // If formatters, rules are registered/known
 // If arguments to rules are valid
-// If version is valid and atleast minimum than commitlint version used
+// If version is valid and at least minimum than commitlint version used
 func Validate(conf *lint.Config) []error {
 	var errs []error
 
@@ -78,7 +78,7 @@ func Validate(conf *lint.Config) []error {
 	for ruleName, sev := range conf.Severity.Rules {
 		// Check Severity Level of rule config
 		if !isSeverityValid(sev) {
-			errs = append(errs, fmt.Errorf("unknown default severity level '%s' for rule '%s'", ruleName, sev))
+			errs = append(errs, fmt.Errorf("unknown severity level '%s' for rule '%s'", sev, ruleName))
 		}
 	}
 

internal/cmd/hook.go

@@ -109,9 +109,9 @@ func getRepoRootDir() (string, error) {
 }
 
 func isHookExists(err error) bool {
-	return err == errHooksExist
+	return errors.Is(err, errHooksExist)
 }
 
 func isConfExists(err error) bool {
-	return err == errConfigExist
+	return errors.Is(err, errConfigExist)
 }

internal/cmd/lint.go

@@ -47,10 +47,7 @@ func runLint(confFilePath, fileInput string) (lintResult string, hasError bool,
 		return "", false, err
 	}
 
-	cleanMsg, err := cleanupMsg(commitMsg)
-	if err != nil {
-		return "", false, err
-	}
+	cleanMsg := cleanupMsg(commitMsg)
 
 	result, err := linter.ParseAndLint(cleanMsg)
 	if err != nil {
@@ -125,7 +122,7 @@ func trimRightSpace(s string) string {
 	return strings.TrimRightFunc(s, unicode.IsSpace)
 }
 
-func cleanupMsg(dirtyMsg string) (string, error) {
+func cleanupMsg(dirtyMsg string) string {
 	// commit msg cleanup in git is configurable: https://git-scm.com/docs/git-commit#Documentation/git-commit.txt---cleanupltmodegt
 	// For now we do a combination of the "scissors" behavior and the "strip" behavior
 	// * remove the scissors line and everything below
@@ -168,7 +165,7 @@ func cleanupMsg(dirtyMsg string) (string, error) {
 		// strip trailing empty line
 		cleanMsg = strings.TrimSuffix(cleanMsg, "\n")
 	}
-	return cleanMsg, nil
+	return cleanMsg
 }
 
 func readStdInPipe() (string, error) {

internal/cmd/util.go

@@ -14,8 +14,8 @@ func (m *multiError) Error() string {
 
 func (m *multiError) Errors() []error {
 	errs := make([]error, len(*m))
-	for _, err := range *m {
-		errs = append(errs, err)
+	for i, err := range *m {
+		errs[i] = err
 	}
 	return errs
 }

rule/body_max_length.go

@@ -0,0 +1,55 @@
+package rule
+
+import "github.com/conventionalcommit/commitlint/lint"
+
+// Compile-time interface checks
+var (
+	_ lint.Rule = (*TypeCharsetRule)(nil)
+	_ lint.Rule = (*ScopeCharsetRule)(nil)
+)
+
+// applyStringArg is a shared helper that extracts a string argument from a RuleSetting.
+func applyStringArg(dst *string, ruleName string, setting lint.RuleSetting) error {
+	if err := setStringArg(dst, setting.Argument); err != nil {
+		return errInvalidArg(ruleName, err)
+	}
+	return nil
+}
+
+// TypeCharsetRule to validate charset of type
+type TypeCharsetRule struct{ Charset string }
+
+func (r *TypeCharsetRule) Name() string { return "type-charset" }
+func (r *TypeCharsetRule) Apply(s lint.RuleSetting) error {
+	return applyStringArg(&r.Charset, r.Name(), s)
+}
+
+func (r *TypeCharsetRule) Validate(msg lint.Commit) (*lint.Issue, bool) {
+	invalidChars, isValid := validateCharset(r.Charset, msg.Type())
+	if isValid {
+		return nil, true
+	}
+	return lint.NewIssue(
+		"type can only have chars ["+r.Charset+"]",
+		"invalid characters ["+invalidChars+"]",
+	), false
+}
+
+// ScopeCharsetRule to validate charset of scope
+type ScopeCharsetRule struct{ Charset string }
+
+func (r *ScopeCharsetRule) Name() string { return "scope-charset" }
+func (r *ScopeCharsetRule) Apply(s lint.RuleSetting) error {
+	return applyStringArg(&r.Charset, r.Name(), s)
+}
+
+func (r *ScopeCharsetRule) Validate(msg lint.Commit) (*lint.Issue, bool) {
+	invalidChars, isValid := validateCharset(r.Charset, msg.Scope())
+	if isValid {
+		return nil, true
+	}
+	return lint.NewIssue(
+		"scope can only have these chars ["+r.Charset+"]",
+		"invalid characters ["+invalidChars+"]",
+	), false
+}