Add test and comment

Author: lunny

modules/git/diff_test.go

@@ -194,3 +194,15 @@ func TestParseDiffHunkString(t *testing.T) {
 	assert.Equal(t, 2, rightLine)
 	assert.Equal(t, 1, rightHunk)
 }
+
+func Test_GetAffectedHunksForTwoCommitsSpecialFile(t *testing.T) {
+	repoPath := "./tests/repos/repo4_commitsbetween"
+	hunks, err := GetAffectedHunksForTwoCommitsSpecialFile(t.Context(), repoPath, "fdc1b615bdcff0f0658b216df0c9209e5ecb7c78", "a78e5638b66ccfe7e1b4689d3d5684e42c97d7ca", "test.txt")
+	assert.NoError(t, err)
+	assert.Len(t, hunks, 1)
+	// @@ -1 +1 @@
+	assert.Equal(t, int64(1), hunks[0].LeftLine)
+	assert.Equal(t, int64(1), hunks[0].LeftHunk)
+	assert.Equal(t, int64(1), hunks[0].RightLine)
+	assert.Equal(t, int64(1), hunks[0].RightHunk)
+}

modules/git/repo_commit.go

@@ -322,6 +322,9 @@ func (repo *Repository) CommitsBetween(lastCommitID, beforeCommitID string) ([]*
 	return commits, nil
 }
 
+// CommitIDsBetween returns a list that contains commit IDs between (beforeCommitID, afterCommitID].
+// If beforeCommitID is empty, it will return all commits before afterCommitID.
+// If beforeCommitID is given, it will not be included in the result.
 func CommitIDsBetween(ctx context.Context, repoPath, beforeCommitID, afterCommitID string) ([]string, error) {
 	var stdout []byte
 	var err error