List authors

cmd/gt/main.go

@@ -109,6 +109,12 @@ func main() {
 				Usage:   "run linter",
 				Action:  withManager(cmdLint),
 			},
+			{
+				Name:    "authors",
+				Aliases: []string{"a"},
+				Usage:   "list all commit authors",
+				Action:  withManager(cmdAuthors),
+			},
 			{
 				Name:    "hooks",
 				Aliases: []string{"h"},
@@ -254,6 +260,43 @@ func cmdLint(ctx context.Context, c *cli.Command, m *repomanager.Manager) error
 	return nil
 }
 
+func cmdAuthors(ctx context.Context, c *cli.Command, m *repomanager.Manager) error {
+	authors, err := m.GetAuthors()
+	if err != nil {
+		return fmt.Errorf("cannot get authors: %w", err)
+	}
+
+	if len(authors) == 0 {
+		fmt.Println("No authors found")
+		return nil
+	}
+
+	// Calculate max widths for better formatting
+	maxNameLen := 0
+	maxEmailLen := 0
+	for _, author := range authors {
+		if len(author.Name) > maxNameLen {
+			maxNameLen = len(author.Name)
+		}
+		if len(author.Email) > maxEmailLen {
+			maxEmailLen = len(author.Email)
+		}
+	}
+
+	// Print header
+	fmt.Printf("%-*s | %-*s | %s\n", maxNameLen, "Name", maxEmailLen, "Email", "Commits")
+	fmt.Printf("%s-+-%s-+-%s\n", strings.Repeat("-", maxNameLen), strings.Repeat("-", maxEmailLen), strings.Repeat("-", 7))
+
+	// Print authors
+	for _, author := range authors {
+		fmt.Printf("%-*s | %-*s | %d\n", maxNameLen, author.Name, maxEmailLen, author.Email, author.Count)
+	}
+
+	fmt.Printf("\nTotal authors: %d\n", len(authors))
+
+	return nil
+}
+
 func cmdHooksList(ctx context.Context, c *cli.Command, m *repomanager.Manager) error {
 	fmt.Println("commit-msg")
 

internal/repo-manager/manager.go

@@ -3,6 +3,7 @@ package repomanager
 import (
 	"errors"
 	"fmt"
+	"github.com/go-git/go-git/v5/plumbing/object"
 	"github.com/go-git/go-git/v5/plumbing/storer"
 	"github.com/kazhuravlev/optional"
 	"sort"
@@ -248,3 +249,53 @@ func (m *Manager) GetCurrentBranch() (string, error) {
 
 	return "", fmt.Errorf("HEAD is not pointing to a branch")
 }
+
+type Author struct {
+	Name  string
+	Email string
+	Count int
+}
+
+func (m *Manager) GetAuthors() ([]Author, error) {
+	commitIter, err := m.repo.CommitObjects()
+	if err != nil {
+		return nil, fmt.Errorf("get commit objects: %w", err)
+	}
+
+	authorMap := make(map[string]*Author)
+
+	err = commitIter.ForEach(func(c *object.Commit) error {
+		email := c.Author.Email
+		if _, exists := authorMap[email]; !exists {
+			authorMap[email] = &Author{
+				Name:  c.Author.Name,
+				Email: email,
+				Count: 0,
+			}
+		}
+		authorMap[email].Count++
+
+		// Update name if it's different (use the most recent name)
+		if authorMap[email].Name != c.Author.Name && c.Author.When.After(c.Committer.When) {
+			authorMap[email].Name = c.Author.Name
+		}
+
+		return nil
+	})
+	if err != nil {
+		return nil, fmt.Errorf("iterate commits: %w", err)
+	}
+
+	// Convert map to slice
+	authors := make([]Author, 0, len(authorMap))
+	for _, author := range authorMap {
+		authors = append(authors, *author)
+	}
+
+	// Sort by commit count (descending)
+	sort.Slice(authors, func(i, j int) bool {
+		return authors[i].Count > authors[j].Count
+	})
+
+	return authors, nil
+}