feat: use skip-detached to skip validation on detached branches

issue: #11

README.md

@@ -97,6 +97,7 @@ branches: # git branches config
         - master
         - main
         - developer
+    skip-detached: false # set true if a detached branch should be ignored on commit message validation
 
 commit-message:
     types: # supported commit types

cmd/git-sv/config.go

@@ -62,6 +62,7 @@ func loadConfig(filepath string) (Config, error) {
 }
 
 func defaultConfig() Config {
+	skipDetached := false
 	return Config{
 		Version: "1.0",
 		Versioning: sv.VersioningConfig{
@@ -77,6 +78,7 @@ func defaultConfig() Config {
 			SuffixRegex:  "(-.*)?",
 			DisableIssue: false,
 			Skip:         []string{"master", "main", "developer"},
+			SkipDetached: &skipDetached,
 		},
 		CommitMessage: sv.CommitMessageConfig{
 			Types: []string{"build", "ci", "chore", "docs", "feat", "fix", "perf", "refactor", "revert", "style", "test"},

cmd/git-sv/handlers.go

@@ -371,8 +371,10 @@ func changelogHandler(git sv.Git, semverProcessor sv.SemVerCommitsProcessor, rnP
 func validateCommitMessageHandler(git sv.Git, messageProcessor sv.MessageProcessor) func(c *cli.Context) error {
 	return func(c *cli.Context) error {
 		branch := git.Branch()
-		if messageProcessor.SkipBranch(branch) {
+		detached, derr := git.IsDetached()
-			warn("commit message validation skipped, branch in ignore list...")
+
+		if messageProcessor.SkipBranch(branch, derr == nil && detached) {
+			warn("commit message validation skipped, branch in ignore list or detached...")
 			return nil
 		}
 

cmd/git-sv/main.go

@@ -4,6 +4,7 @@ import (
 	"log"
 	"os"
 	"path/filepath"
+	"reflect"
 	"sv4git/sv"
 
 	"github.com/imdario/mergo"
@@ -27,7 +28,7 @@ func main() {
 
 	if envCfg.Home != "" {
 		if homeCfg, err := loadConfig(filepath.Join(envCfg.Home, configFilename)); err == nil {
-			if merr := mergo.Merge(&cfg, homeCfg, mergo.WithOverride); merr != nil {
+			if merr := mergo.Merge(&cfg, homeCfg, mergo.WithOverride, mergo.WithTransformers(&nullTransformer{})); merr != nil {
 				log.Fatal(merr)
 			}
 		}
@@ -39,7 +40,7 @@ func main() {
 	}
 
 	if repoCfg, err := loadConfig(filepath.Join(repoPath, repoConfigFilename)); err == nil {
-		if merr := mergo.Merge(&cfg, repoCfg, mergo.WithOverride); merr != nil {
+		if merr := mergo.Merge(&cfg, repoCfg, mergo.WithOverride, mergo.WithTransformers(&nullTransformer{})); merr != nil {
 			log.Fatal(merr)
 		}
 		if len(repoCfg.ReleaseNotes.Headers) > 0 { // mergo is merging maps, headers will be overwritten
@@ -159,3 +160,18 @@ func main() {
 		log.Fatal(apperr)
 	}
 }
+
+type nullTransformer struct {
+}
+
+func (t *nullTransformer) Transformer(typ reflect.Type) func(dst, src reflect.Value) error {
+	if typ.Kind() == reflect.Ptr {
+		return func(dst, src reflect.Value) error {
+			if dst.CanSet() && !src.IsNil() {
+				dst.Set(src)
+			}
+			return nil
+		}
+	}
+	return nil
+}

sv/config.go

@@ -43,6 +43,7 @@ type BranchesConfig struct {
 	SuffixRegex  string   `yaml:"suffix"`
 	DisableIssue bool     `yaml:"disable-issue"`
 	Skip         []string `yaml:"skip"`
+	SkipDetached *bool    `yaml:"skip-detached"`
 }
 
 // ==== Versioning ====

sv/git.go

@@ -3,6 +3,7 @@ package sv
 import (
 	"bufio"
 	"bytes"
+	"errors"
 	"fmt"
 	"os"
 	"os/exec"
@@ -25,6 +26,7 @@ type Git interface {
 	Tag(version semver.Version) error
 	Tags() ([]GitTag, error)
 	Branch() string
+	IsDetached() (bool, error)
 }
 
 // GitCommitLog description of a single commit log
@@ -154,6 +156,19 @@ func (GitImpl) Branch() string {
 	return strings.TrimSpace(strings.Trim(string(out), "\n"))
 }
 
+// IsDetached check if is detached.
+func (GitImpl) IsDetached() (bool, error) {
+	cmd := exec.Command("git", "symbolic-ref", "-q", "HEAD")
+	out, err := cmd.CombinedOutput()
+	if output := string(out); err != nil { //-q: do not issue an error message if the <name> is not a symbolic ref, but a detached HEAD; instead exit with non-zero status silently.
+		if output == "" {
+			return true, nil
+		}
+		return false, errors.New(output)
+	}
+	return false, nil
+}
+
 func parseTagsOutput(input string) ([]GitTag, error) {
 	scanner := bufio.NewScanner(strings.NewReader(input))
 	var result []GitTag

sv/message.go

@@ -47,7 +47,7 @@ func (m CommitMessage) BreakingMessage() string {
 
 // MessageProcessor interface.
 type MessageProcessor interface {
-	SkipBranch(branch string) bool
+	SkipBranch(branch string, detached bool) bool
 	Validate(message string) error
 	Enhance(branch string, message string) (string, error)
 	IssueID(branch string) (string, error)
@@ -70,8 +70,8 @@ type MessageProcessorImpl struct {
 }
 
 // SkipBranch check if branch should be ignored.
-func (p MessageProcessorImpl) SkipBranch(branch string) bool {
+func (p MessageProcessorImpl) SkipBranch(branch string, detached bool) bool {
-	return contains(branch, p.branchesCfg.Skip)
+	return contains(branch, p.branchesCfg.Skip) || (p.branchesCfg.SkipDetached != nil && *p.branchesCfg.SkipDetached && detached)
 }
 
 // Validate commit message.

sv/message_test.go

@@ -25,10 +25,13 @@ var ccfgWithScope = CommitMessageConfig{
 	Issue: CommitMessageIssueConfig{Regex: "[A-Z]+-[0-9]+"},
 }
 
-var bcfg = BranchesConfig{
+func newBranchCfg(skipDetached bool) BranchesConfig {
-	PrefixRegex: "([a-z]+\\/)?",
+	return BranchesConfig{
-	SuffixRegex: "(-.*)?",
+		PrefixRegex:  "([a-z]+\\/)?",
-	Skip:        []string{"develop", "master"},
+		SuffixRegex:  "(-.*)?",
+		Skip:         []string{"develop", "master"},
+		SkipDetached: &skipDetached,
+	}
 }
 
 // messages samples start
@@ -67,6 +70,30 @@ BREAKING CHANGE: refactor to use JavaScript features not available in Node 6.`
 
 // multiline samples end
 
+func TestMessageProcessorImpl_SkipBranch(t *testing.T) {
+	tests := []struct {
+		name     string
+		bcfg     BranchesConfig
+		branch   string
+		detached bool
+		want     bool
+	}{
+		{"normal branch", newBranchCfg(false), "JIRA-123", false, false},
+		{"dont ignore detached branch", newBranchCfg(false), "JIRA-123", true, false},
+		{"ignore branch on skip list", newBranchCfg(false), "master", false, true},
+		{"ignore detached branch", newBranchCfg(true), "JIRA-123", true, true},
+		{"null skip detached", BranchesConfig{Skip: []string{}}, "JIRA-123", true, false},
+	}
+	for _, tt := range tests {
+		t.Run(tt.name, func(t *testing.T) {
+			p := NewMessageProcessor(ccfg, tt.bcfg)
+			if got := p.SkipBranch(tt.branch, tt.detached); got != tt.want {
+				t.Errorf("MessageProcessorImpl.SkipBranch() = %v, want %v", got, tt.want)
+			}
+		})
+	}
+}
+
 func TestMessageProcessorImpl_Validate(t *testing.T) {
 	tests := []struct {
 		name    string
@@ -94,7 +121,7 @@ func TestMessageProcessorImpl_Validate(t *testing.T) {
 	}
 	for _, tt := range tests {
 		t.Run(tt.name, func(t *testing.T) {
-			p := NewMessageProcessor(tt.cfg, bcfg)
+			p := NewMessageProcessor(tt.cfg, newBranchCfg(false))
 			if err := p.Validate(tt.message); (err != nil) != tt.wantErr {
 				t.Errorf("MessageProcessorImpl.Validate() error = %v, wantErr %v", err, tt.wantErr)
 			}
@@ -103,7 +130,7 @@ func TestMessageProcessorImpl_Validate(t *testing.T) {
 }
 
 func TestMessageProcessorImpl_Enhance(t *testing.T) {
-	p := NewMessageProcessor(ccfg, bcfg)
+	p := NewMessageProcessor(ccfg, newBranchCfg(false))
 
 	tests := []struct {
 		name    string
@@ -136,7 +163,7 @@ func TestMessageProcessorImpl_Enhance(t *testing.T) {
 }
 
 func TestMessageProcessorImpl_IssueID(t *testing.T) {
-	p := NewMessageProcessor(ccfg, bcfg)
+	p := NewMessageProcessor(ccfg, newBranchCfg(false))
 
 	tests := []struct {
 		name    string
@@ -248,7 +275,7 @@ Jira: JIRA-999
 Refs #123`
 
 func TestMessageProcessorImpl_Parse(t *testing.T) {
-	p := NewMessageProcessor(ccfg, bcfg)
+	p := NewMessageProcessor(ccfg, newBranchCfg(false))
 
 	tests := []struct {
 		name    string
@@ -275,7 +302,7 @@ func TestMessageProcessorImpl_Parse(t *testing.T) {
 }
 
 func TestMessageProcessorImpl_Format(t *testing.T) {
-	p := NewMessageProcessor(ccfg, bcfg)
+	p := NewMessageProcessor(ccfg, newBranchCfg(false))
 
 	tests := []struct {
 		name       string