feat(music-lab): pipeline 상태 머신

music-lab/tests/test_state_machine.py

@@ -0,0 +1,49 @@
+import pytest
+from app.pipeline.state_machine import (
+    next_state_on_approve, next_state_on_reject, can_transition, STEPS, USER_GATES,
+)
+
+
+def test_steps_sequence():
+    assert STEPS == ["cover", "video", "thumb", "meta", "review", "publish"]
+
+
+def test_user_gates_excludes_review():
+    assert "review" not in USER_GATES
+    assert "publish" in USER_GATES
+    assert "cover" in USER_GATES
+
+
+def test_approve_progression():
+    assert next_state_on_approve("cover_pending") == "video_pending"
+    assert next_state_on_approve("video_pending") == "thumb_pending"
+    assert next_state_on_approve("thumb_pending") == "meta_pending"
+    assert next_state_on_approve("meta_pending") == "ai_review"
+    assert next_state_on_approve("publish_pending") == "publishing"
+
+
+def test_approve_invalid_state_raises():
+    with pytest.raises(ValueError):
+        next_state_on_approve("ai_review")  # 자동 전이 — approve 호출 자체가 무효
+
+
+def test_reject_keeps_same_state():
+    # 반려는 같은 *_pending 상태를 유지(재생성 트리거)
+    assert next_state_on_reject("cover_pending") == "cover_pending"
+    assert next_state_on_reject("publish_pending") == "publish_pending"
+
+
+def test_can_transition_blocks_terminal_states():
+    assert not can_transition("published", "cover_pending")
+    assert not can_transition("cancelled", "cover_pending")
+    assert not can_transition("failed", "cover_pending")
+
+
+def test_can_transition_allows_cancel_from_anywhere():
+    assert can_transition("cover_pending", "cancelled")
+    assert can_transition("publishing", "cancelled")
+
+
+def test_can_transition_allows_failed_from_pending():
+    assert can_transition("video_pending", "failed")
+    assert can_transition("publishing", "failed")