Find the base directory of a git repo in Golang

get-repo-base.go

package lib

// GetRepoBase get the directory that contains the .git directory for this repository. This DOES NOT give you the path
// you are running from or the path of the executable if you're running a binary from "go build". If your repo looks
// like this:
//
// - repo
//   - .git
//   - main.go
//   - lib
//   - shared.go
//
// And this function is in shared.go it will return the absolute path of `repo` even when using a binary that is running
// on another system. This function is useful for referencing data files inside a code base.
func GetRepoBase() string {
	// Find the path of this current file
	// NOTE: This means the current .go file in your source code repo, NOT where the compiled binary exists or is running from!
	_, b, _, _ := runtime.Caller(0)

	// Get the directory the file is in
	basePath := filepath.Dir(b)

	// Make sure we don't end up in a loop by checking if our last path is the same as the current path
	lastBasePath := ""

	// Make sure we don't end up in a loop by checking to see if we do too many iterations
	maximumIterations := 50
	iterationCount := 0

	for {
		gitDirectory := path.Join(basePath, ".git")

		_, err := os.Stat(gitDirectory)

		if err == nil {
			// .git exists, we are done
			// NOTE: This means this may not work as expected when using submodules or nested repos
			return filepath.Dir(gitDirectory)
		}

		basePath = filepath.Dir(basePath)

		iterationCount++

		if iterationCount >= maximumIterations {
			break
		}

		if lastBasePath == basePath {
			break
		}

		lastBasePath = basePath
	}

	return ""
}