feat: optional support bump pre-release number

README.md

@@ -181,6 +181,8 @@ autotag --strict-match
 
 - Use `-T/--pre-release-timestmap=` to append **timestamp** to the version. Allowed timetstamp
   formats are `datetime` (YYYYMMDDHHMMSS) or `epoch` (UNIX epoch timestamp in seconds).
+
+- Use `--pre-release-number` to append pre-release number to the version. Pre-release is also mentioned in the [SemVer](https://semver.org/#spec-item-9) spec. Note: `--pre-release-number` is used only when option `--pre-release-timestmap` isn't enabled.
 
 ### Build metadata
 

autotag.go

@@ -99,6 +99,15 @@ type GitRepoConfig struct {
 	// 		v1.2.3-pre.1499308568
 	PreReleaseTimestampLayout string
 
+	// PreReleaseNumber is the optional flag that's used to tell program append a
+	// build number to the git tag as second part of prerelease.
+	//
+	// Assuming PreReleaseName is set to `pre`, the PreReleaseBuildNumber is appended to
+	// that value separated by a period (`.`):
+	//
+	// 		v1.2.3-pre.1
+	PreReleaseNumber bool
+
 	// BuildMetadata is an optional string appended by a plus sign and a series of dot separated
 	// identifiers immediately following the patch or pre-release version. Identifiers MUST comprise
 	// only ASCII alphanumerics and hyphen [0-9A-Za-z-]. Identifiers MUST NOT be empty. Build metadata
@@ -146,11 +155,13 @@ type GitRepo struct {
 	branch         string
 	branchID       string // commit id of the branch latest commit (where we will apply the tag)
 
+	curPreReleaseVer *version.Version
 	latestTagVersion *version.Version
 	latestTagCommit  *git.Commit
 
 	preReleaseName            string
 	preReleaseTimestampLayout string
+	preReleaseNumber          bool
 	buildMetadata             string
 
 	scheme      string
@@ -214,6 +225,7 @@ func NewRepo(cfg GitRepoConfig) (*GitRepo, error) {
 		branch:                    cfg.Branch,
 		preReleaseName:            cfg.PreReleaseName,
 		preReleaseTimestampLayout: cfg.PreReleaseTimestampLayout,
+		preReleaseNumber:          cfg.PreReleaseNumber,
 		buildMetadata:             cfg.BuildMetadata,
 		scheme:                    cfg.Scheme,
 		prefix:                    cfg.Prefix,
@@ -310,6 +322,13 @@ func (r *GitRepo) parseTags() error {
 			r.latestTagCommit = versions[version]
 		}
 
+		// stamps latest tag for pre-release
+		if r.preReleaseName != "" && version.Prerelease() != "" && r.curPreReleaseVer == nil {
+			if strings.HasPrefix(version.Prerelease(), fmt.Sprintf("%s.", r.preReleaseName)) {
+				r.curPreReleaseVer = version
+			}
+		}
+
 		if len(version.Prerelease()) == 0 {
 			r.currentVersion = version
 			r.currentTag = versions[version]
@@ -365,7 +384,7 @@ func (r *GitRepo) retrieveBranchInfo() error {
 	return nil
 }
 
-func preReleaseVersion(v *version.Version, name, tsLayout string) (*version.Version, error) {
+func preReleaseVersion(v, curPrereleaseVer *version.Version, name, tsLayout string, autoIncrease bool) (*version.Version, error) {
 	if len(name) == 0 && len(tsLayout) == 0 {
 		return v, nil
 	}
@@ -405,6 +424,33 @@ func preReleaseVersion(v *version.Version, name, tsLayout string) (*version.Vers
 		if _, err := buf.WriteString(timestamp); err != nil {
 			return nil, err
 		}
+	} else {
+		if len(name) > 0 && autoIncrease {
+			// Write the `.` character
+			if buf.Len() > 0 {
+				if _, err := buf.WriteString("."); err != nil {
+					return nil, err
+				}
+			}
+
+			prereleaseNumber := "1"
+			if curPrereleaseVer != nil {
+				prerelease := curPrereleaseVer.Prerelease()
+				prereleaseParts := strings.Split(prerelease, ".")
+				if len(prereleaseParts) == 2 {
+					currentPrereleaseNumber, err := strconv.ParseUint(prereleaseParts[1], 10, 64)
+					if err != nil {
+						return nil, fmt.Errorf("prerelease build number must be a unsigned integer")
+					}
+
+					prereleaseNumber = strconv.FormatUint(currentPrereleaseNumber+1, 10)
+				}
+			}
+
+			if _, err := buf.WriteString(prereleaseNumber); err != nil {
+				return nil, err
+			}
+		}
 	}
 
 	verStr := fmt.Sprintf("%s-%s", v.String(), buf.String())
@@ -466,7 +512,7 @@ func (r *GitRepo) calcVersion() error {
 
 	// append pre-release-name and/or pre-release-timestamp to the version
 	if len(r.preReleaseName) > 0 || len(r.preReleaseTimestampLayout) > 0 {
-		if r.newVersion, err = preReleaseVersion(r.newVersion, r.preReleaseName, r.preReleaseTimestampLayout); err != nil {
+		if r.newVersion, err = preReleaseVersion(r.newVersion, r.curPreReleaseVer, r.preReleaseName, r.preReleaseTimestampLayout, r.preReleaseNumber); err != nil {
 			return err
 		}
 	}

autotag/main.go

@@ -18,6 +18,7 @@ type Options struct {
 	RepoPath            string `short:"r" long:"repo" description:"Path to the repo" default:"./" `
 	PreReleaseName      string `short:"p" long:"pre-release-name" description:"create a pre-release tag"`
 	PreReleaseTimestamp string `short:"T" long:"pre-release-timestamp" description:"create a pre-release tag and append a timestamp (can be: datetime|epoch)"`
+	PreReleaseNumber    bool   `long:"pre-release-number" description:"create a pre-release tag and append a pre-release number"`
 	BuildMetadata       string `short:"m" long:"build-metadata" description:"optional SemVer build metadata to append to the version with '+' character"`
 	Scheme              string `short:"s" long:"scheme" description:"The commit message scheme to use (can be: autotag|conventional)" default:"autotag"`
 	NoVersionPrefix     bool   `short:"e" long:"empty-version-prefix" description:"Do not prepend v to version tag"`
@@ -46,6 +47,7 @@ func main() {
 		Branch:                    opts.Branch,
 		PreReleaseName:            opts.PreReleaseName,
 		PreReleaseTimestampLayout: opts.PreReleaseTimestamp,
+		PreReleaseNumber:          opts.PreReleaseNumber,
 		BuildMetadata:             opts.BuildMetadata,
 		Scheme:                    opts.Scheme,
 		Prefix:                    !opts.NoVersionPrefix,

autotag_test.go

@@ -37,6 +37,9 @@ type testRepoSetup struct {
 	// (optional) the prerelease timestamp format to use, eg: "epoch". If not set, no prerelease timestamp will be used
 	preReleaseTimestampLayout string
 
+	// (optional) will optional append prerelease number in second part of prerelease (default: false)
+	preReleaseNumber bool
+
 	// (optional) build metadata to append to the version
 	buildMetadata string
 
@@ -103,6 +106,7 @@ func newTestRepo(t *testing.T, setup testRepoSetup) (GitRepo, error) {
 		Branch:                    branch,
 		PreReleaseName:            setup.preReleaseName,
 		PreReleaseTimestampLayout: setup.preReleaseTimestampLayout,
+		PreReleaseNumber:          setup.preReleaseNumber,
 		BuildMetadata:             setup.buildMetadata,
 		Scheme:                    setup.scheme,
 		Prefix:                    !setup.disablePrefix,
@@ -437,6 +441,81 @@ func TestPatch(t *testing.T) {
 	}
 }
 
+func TestPrereleaseNumberFirstTime(t *testing.T) {
+	r, err := newTestRepo(t, testRepoSetup{
+		preReleaseNumber: true,
+		preReleaseName:   "dev",
+		initialTag:       "v1.0.1",
+	})
+	if err != nil {
+		t.Fatal("Error creating repo: ", err)
+	}
+	defer cleanupTestRepo(t, r.repo)
+
+	v := r.LatestVersion()
+
+	if v != "1.0.2-dev.1" {
+		t.Fatalf("Prerelease number bump failed expected '1.0.2-dev.1' got '%s' \n", v)
+	}
+}
+
+func TestPrereleaseNumber(t *testing.T) {
+	r, err := newTestRepo(t, testRepoSetup{
+		preReleaseNumber: true,
+		preReleaseName:   "dev",
+		initialTag:       "v1.0.1",
+		extraTags:        []string{"v1.0.2-dev.1"},
+	})
+	if err != nil {
+		t.Fatal("Error creating repo: ", err)
+	}
+	defer cleanupTestRepo(t, r.repo)
+
+	v := r.LatestVersion()
+
+	if v != "1.0.2-dev.2" {
+		t.Fatalf("Prerelease number bump failed expected '1.0.2-dev.2' got '%s' \n", v)
+	}
+}
+
+func TestPrereleaseNumberWithExtraTags(t *testing.T) {
+	r, err := newTestRepo(t, testRepoSetup{
+		preReleaseNumber: true,
+		preReleaseName:   "dev",
+		initialTag:       "v1.0.1",
+		extraTags:        []string{"v1.0.2-dev.1", "v1.0.2-next.1"},
+	})
+	if err != nil {
+		t.Fatal("Error creating repo: ", err)
+	}
+	defer cleanupTestRepo(t, r.repo)
+
+	v := r.LatestVersion()
+
+	if v != "1.0.2-dev.2" {
+		t.Fatalf("Prerelease number bump failed expected '1.0.2-dev.2' got '%s' \n", v)
+	}
+}
+
+func TestPrereleaseNumberWithNewVersion(t *testing.T) {
+	r, err := newTestRepo(t, testRepoSetup{
+		preReleaseNumber: true,
+		preReleaseName:   "dev",
+		initialTag:       "v1.0.1",
+		extraTags:        []string{"v1.0.2-dev.1", "v1.0.2"},
+	})
+	if err != nil {
+		t.Fatal("Error creating repo: ", err)
+	}
+	defer cleanupTestRepo(t, r.repo)
+
+	v := r.LatestVersion()
+
+	if v != "1.0.3-dev.1" {
+		t.Fatalf("Prerelease number bump failed expected '1.0.3-dev.1' got '%s' \n", v)
+	}
+}
+
 func TestBuildNumberFirstTime(t *testing.T) {
 	r, err := newTestRepo(t, testRepoSetup{
 		buildNumber: true,