feat(controller): more git pkg improvements (#2531)

Signed-off-by: Kent Rancourt <[email protected]>

internal/controller/git/bare_repo.go

@@ -14,9 +14,8 @@ import (
 
 // BareRepo is an interface for interacting with a bare Git repository.
 type BareRepo interface {
-	// AddWorkTree adds a working tree to the repository. The working tree will be
-	// created at the specified path and will be checked out to the specified ref.
-	AddWorkTree(path, ref string) (WorkTree, error)
+	// AddWorkTree adds a working tree to the repository.
+	AddWorkTree(path string, opts *AddWorkTreeOptions) (WorkTree, error)
 	// Close cleans up file system resources used by this repository. This should
 	// always be called before a repository goes out of scope.
 	Close() error
@@ -25,6 +24,9 @@ type BareRepo interface {
 	// HomeDir returns an absolute path to the home directory of the system user
 	// who has cloned this repo.
 	HomeDir() string
+	// RemoteBranchExists returns a bool indicating if the specified branch exists
+	// in the remote repository.
+	RemoteBranchExists(branch string) (bool, error)
 	// RemoveWorkTree removes a working tree from the repository. The working tree
 	// will be removed from the file system.
 	RemoveWorkTree(path string) error
@@ -135,7 +137,21 @@ func LoadBareRepo(path string, opts *LoadBareRepoOptions) (BareRepo, error) {
 	return b, nil
 }
 
-func (b *bareRepo) AddWorkTree(path, ref string) (WorkTree, error) {
+// AddWorkTreeOptions represents options for adding a working tree to a bare
+// repository.
+type AddWorkTreeOptions struct {
+	// Orphan specifies whether the working tree should be created from a new,
+	// orphaned branch. If true, the Ref field will be ignored.
+	Orphan bool
+	// Ref specifies the branch or commit to check out in the working tree. Will
+	// be ignored if Orphan is true.
+	Ref string
+}
+
+func (b *bareRepo) AddWorkTree(path string, opts *AddWorkTreeOptions) (WorkTree, error) {
+	if opts == nil {
+		opts = &AddWorkTreeOptions{}
+	}
 	path, err := filepath.Abs(path)
 	if err != nil {
 		return nil, fmt.Errorf("error resolving absolute path for %s: %w", path, err)
@@ -147,9 +163,13 @@ func (b *bareRepo) AddWorkTree(path, ref string) (WorkTree, error) {
 	if slices.Contains(workTreePaths, path) {
 		return nil, fmt.Errorf("working tree already exists at %q", path)
 	}
-	if _, err = libExec.Exec(
-		b.buildGitCommand("worktree", "add", path, ref),
-	); err != nil {
+	args := []string{"worktree", "add", path}
+	if opts.Orphan {
+		args = append(args, "--orphan")
+	} else {
+		args = append(args, opts.Ref)
+	}
+	if _, err = libExec.Exec(b.buildGitCommand(args...)); err != nil {
 		return nil, fmt.Errorf("error adding working tree at %q: %w", path, err)
 	}
 	if path, err = filepath.EvalSymlinks(path); err != nil {

internal/controller/git/bare_repo_test.go

@@ -107,9 +107,13 @@ func TestBareRepo(t *testing.T) {
 	})
 
 	workingTreePath := filepath.Join(rep.HomeDir(), "working-tree")
-	// "master" is still the default branch name for a new repository unless
-	// you configure it otherwise.
-	workTree, err := rep.AddWorkTree(workingTreePath, "master")
+	workTree, err := rep.AddWorkTree(
+		workingTreePath,
+		// "master" is still the default branch name for a new repository unless
+		// you configure it otherwise.
+		&AddWorkTreeOptions{Ref: "master"},
+	)
+
 	require.NoError(t, err)
 	defer workTree.Close()
 

internal/controller/git/base_repo.go

@@ -1,6 +1,7 @@
 package git
 
 import (
+	"errors"
 	"fmt"
 	"net/url"
 	"os"
@@ -244,6 +245,30 @@ func (b *baseRepo) HomeDir() string {
 	return b.homeDir
 }
 
+func (b *baseRepo) RemoteBranchExists(branch string) (bool, error) {
+	_, err := libExec.Exec(b.buildGitCommand(
+		"ls-remote",
+		"--heads",
+		"--exit-code", // Return 2 if not found
+		b.url,
+		branch,
+	))
+	var exitErr *libExec.ExitError
+	if errors.As(err, &exitErr) && exitErr.ExitCode == 2 {
+		// Branch does not exist
+		return false, nil
+	}
+	if err != nil {
+		return false, fmt.Errorf(
+			"error checking for existence of branch %q in remote repo %q: %w",
+			branch,
+			b.url,
+			err,
+		)
+	}
+	return true, nil
+}
+
 func (b *baseRepo) URL() string {
 	return b.url
 }

internal/controller/git/work_tree.go

@@ -23,6 +23,8 @@ type WorkTree interface {
 	AddAllAndCommit(message string) error
 	// Clean cleans the working tree.
 	Clean() error
+	// Clear executes `git rm -rf .` to remove all files from the working tree.
+	Clear() error
 	// Close cleans up file system resources used by this working tree. This
 	// should always be called before a WorkTree goes out of scope.
 	Close() error
@@ -150,6 +152,15 @@ func (w *workTree) Clean() error {
 	return nil
 }
 
+func (w *workTree) Clear() error {
+	if _, err := libExec.Exec(
+		w.buildGitCommand("rm", "-rf", "--ignore-unmatch", "."),
+	); err != nil {
+		return fmt.Errorf("error clearing worktree: %w", err)
+	}
+	return nil
+}
+
 func (w *workTree) Close() error {
 	if w.bareRepo != nil {
 		return w.bareRepo.RemoveWorkTree(w.dir)
@@ -496,30 +507,6 @@ func (w *workTree) RefsHaveDiffs(commit1 string, commit2 string) (bool, error) {
 	return false, fmt.Errorf("error diffing commits %s..%s: %w", commit1, commit2, err)
 }
 
-func (w *workTree) RemoteBranchExists(branch string) (bool, error) {
-	_, err := libExec.Exec(w.buildGitCommand(
-		"ls-remote",
-		"--heads",
-		"--exit-code", // Return 2 if not found
-		w.url,
-		branch,
-	))
-	var exitErr *libExec.ExitError
-	if errors.As(err, &exitErr) && exitErr.ExitCode == 2 {
-		// Branch does not exist
-		return false, nil
-	}
-	if err != nil {
-		return false, fmt.Errorf(
-			"error checking for existence of branch %q in remote repo %q: %w",
-			branch,
-			w.url,
-			err,
-		)
-	}
-	return true, nil
-}
-
 func (w *workTree) ResetHard() error {
 	if _, err := libExec.Exec(w.buildGitCommand("reset", "--hard")); err != nil {
 		return fmt.Errorf("error resetting branch working tree: %w", err)

internal/controller/git/work_tree_test.go

@@ -75,9 +75,12 @@ func TestWorkTree(t *testing.T) {
 	defer rep.Close()
 
 	workingTreePath := filepath.Join(rep.HomeDir(), "working-tree")
-	// "master" is still the default branch name for a new repository unless
-	// you configure it otherwise.
-	workTree, err := rep.AddWorkTree(workingTreePath, "master")
+	workTree, err := rep.AddWorkTree(
+		workingTreePath,
+		// "master" is still the default branch name for a new repository unless
+		// you configure it otherwise.
+		&AddWorkTreeOptions{Ref: "master"},
+	)
 	require.NoError(t, err)
 	defer workTree.Close()