A Go library for parsing Git .mailmap files and resolving author identities. It uses only the standard library and supports the four mailmap entry forms for replacing names, email addresses, or both.

go get github.com/git-pkgs/mailmap

package main

import (
	"fmt"
	"log"
	"strings"

	"github.com/git-pkgs/mailmap"
)

func main() {
	m, err := mailmap.Parse(strings.NewReader(`Jane Doe <[email protected]> <jane@laptop.(none)>
`))
	if err != nil {
		log.Fatal(err)
	}
	name, email := m.Resolve("jane", "jane@laptop.(none)")
	fmt.Printf("%s <%s>\n", name, email)
	// Jane Doe <[email protected]>
}

Parse accepts an io.Reader, including an open .mailmap file. New() creates an empty map; empty, zero-value, and nil maps return identities unchanged.

Matching ignores case for names and email addresses, and entries matching both take priority over entries matching only email. The last matching entry in each group wins; unmatched identities are returned unchanged.

Blank lines, comments starting with #, and malformed entries are skipped. Reader errors and lines exceeding the default bufio.Scanner token limit return an error along with the entries parsed so far.

MIT.