Check av's state file and REBASE_HEAD to prevent conflict

internal/git/rebase.go

@@ -1,12 +1,18 @@
 package git
 
 import (
+	"fmt"
+	"os"
+	"path/filepath"
 	"regexp"
 	"strings"
 
 	"github.com/sirupsen/logrus"
 )
 
+// ref: https://git-scm.com/docs/git-rev-parse#Documentation/git-rev-parse.txt-codeREBASEHEADcode
+const REBASE_STATE_FILE = "REBASE_HEAD"
+
 type RebaseOpts struct {
 	// Required (unless Continue is true)
 	// The upstream branch to rebase onto.
@@ -57,6 +63,10 @@ func (r *Repo) Rebase(opts RebaseOpts) (*Output, error) {
 		args = append(args, opts.Branch)
 	}
 
+	if _, err := os.Stat(filepath.Join(r.GitDir(), REBASE_STATE_FILE)); err == nil {
+		return nil, fmt.Errorf("failed to start rebase: rebase in progress")
+	}
+
 	return r.Run(&RunOpts{Args: args})
 }
 

internal/git/state_file.go

@@ -2,6 +2,7 @@ package git
 
 import (
 	"encoding/json"
+	"fmt"
 	"os"
 	"path/filepath"
 )
@@ -32,9 +33,15 @@ func (r *Repo) WriteStateFile(kind StateFileKind, msg any) error {
 		return nil
 	}
 
+	file := filepath.Join(r.AvDir(), string(kind))
+	if _, err := os.Stat(file); err == nil {
+		// When the state file already exists, it means that during fixing conflicts
+		return fmt.Errorf("Please execute the command after fixing the conflict")
+	}
+
 	bs, err := json.MarshalIndent(msg, "", "  ")
 	if err != nil {
 		return err
 	}
-	return os.WriteFile(filepath.Join(r.AvDir(), string(kind)), bs, 0644)
+	return os.WriteFile(file, bs, 0644)
 }

internal/git/state_file_test.go

@@ -0,0 +1,34 @@
+package git_test
+
+import (
+	"testing"
+
+	"github.com/aviator-co/av/internal/git"
+	"github.com/aviator-co/av/internal/git/gittest"
+	"github.com/stretchr/testify/require"
+)
+
+func TestWriteStateFile(t *testing.T) {
+	type Test struct {
+		Message string
+	}
+
+	tmpRepo := gittest.NewTempRepo(t)
+	repo, err := git.OpenRepo(tmpRepo.RepoDir, tmpRepo.GitDir)
+	require.NoError(t, err)
+
+	err = repo.WriteStateFile(git.StateFileKindSync, &Test{Message: "test write kind sync"})
+	require.NoError(t, err)
+
+	// Already state file exists, thus it should return an error
+	err = repo.WriteStateFile(git.StateFileKindSync, &Test{Message: "test write kind sync 2"})
+	require.Error(t, err)
+
+	// clean up
+	err = repo.WriteStateFile(git.StateFileKindSync, nil)
+	require.NoError(t, err)
+
+	// Write again
+	err = repo.WriteStateFile(git.StateFileKindSync, &Test{Message: "test write kind sync 2"})
+	require.NoError(t, err)
+}