fix test missing files

tests/node_tests/image_demo.py

@@ -1,4 +1,4 @@
-import os
+from pathlib import Path
 from unittest.mock import patch
 
 import numpy as np
@@ -6,71 +6,76 @@ from backend.data_types import DataField
 from backend.execution import ExecutionEngine
 import backend.nodes  # noqa: F401
 
+FIXTURES = Path(__file__).parent.parent / "output"
 
-def test_load_demo():
+
+def test_load_npy():
     from backend.nodes.image_demo import ImageDemo
-    from backend.nodes.helpers import DEMO_DIR
-    node = ImageDemo()
 
-    result = node.load(name="nanoparticles.npy")
+    with patch("backend.nodes.image_demo.DEMO_DIR", FIXTURES):
+        result = ImageDemo().load(name="nanoparticles.npy")
+
     # result[0] is the FILE_PATH string, fields follow
     assert len(result) >= 2
     assert isinstance(result[0], str)
     assert isinstance(result[1], DataField)
     assert result[1].data.ndim == 2
 
-    ibw_path = DEMO_DIR / "whiskers.ibw"
-    if ibw_path.exists():
-        result_ibw = node.load(name="whiskers.ibw")
-        fields = [v for v in result_ibw if isinstance(v, DataField)]
-        assert len(fields) == 4
-        for field in fields:
-            assert isinstance(field, DataField)
 
-    try:
-        node.load(name="nonexistent_file.png")
-        assert False, "Should have raised FileNotFoundError"
-    except FileNotFoundError:
-        pass
+def test_load_ibw_multi_channel():
+    from backend.nodes.image_demo import ImageDemo
+
+    with patch("backend.nodes.image_demo.DEMO_DIR", FIXTURES):
+        result = ImageDemo().load(name="Bacteria.ibw")
+
+    fields = [v for v in result if isinstance(v, DataField)]
+    assert len(fields) == 4
+    for field in fields:
+        assert field.data.ndim == 2
 
 
-def test_load_demo_cache():
+def test_load_not_found():
+    from backend.nodes.image_demo import ImageDemo
+
+    with patch("backend.nodes.image_demo.DEMO_DIR", FIXTURES):
+        try:
+            ImageDemo().load(name="nonexistent_file.png")
+            assert False, "Should have raised FileNotFoundError"
+        except FileNotFoundError:
+            pass
+
+
+def test_load_cache():
     from backend.nodes.image import Image
     from backend.nodes.image_demo import ImageDemo
 
     node = ImageDemo()
     Image._load_fields_cached.cache_clear()
 
-    with patch.object(Image, "_load_image_or_array", wraps=Image._load_image_or_array) as loader:
-        _, first = node.load(name="nanoparticles.npy")
-        _, second = node.load(name="nanoparticles.npy")
-        assert loader.call_count == 1
+    with patch("backend.nodes.image_demo.DEMO_DIR", FIXTURES):
+        with patch.object(Image, "_load_image_or_array", wraps=Image._load_image_or_array) as loader:
+            _, first = node.load(name="nanoparticles.npy")
+            _, second = node.load(name="nanoparticles.npy")
+            assert loader.call_count == 1
 
-    assert np.allclose(first.data, second.data)
-    assert first is not second
-    first.data[0, 0] = -999.0
+        assert np.allclose(first.data, second.data)
+        assert first is not second
+        first.data[0, 0] = -999.0
 
-    _, third = node.load(name="nanoparticles.npy")
-    assert third.data[0, 0] != -999.0
+        _, third = node.load(name="nanoparticles.npy")
+        assert third.data[0, 0] != -999.0
 
     Image._load_fields_cached.cache_clear()
 
 
-def test_load_demo_multi_layer_preview_payload():
-    from backend.nodes.helpers import DEMO_DIR
-    ibw_path = DEMO_DIR / "whiskers.ibw"
-    if not ibw_path.exists():
-        return
-
+def test_multi_layer_preview_payload():
     previews = []
-    prompt = {
-        "1": {
-            "class_type": "ImageDemo",
-            "inputs": {"name": "whiskers.ibw", "colormap": "viridis"},
-        },
-    }
 
-    ExecutionEngine().execute(prompt, on_preview=lambda node_id, payload: previews.append((node_id, payload)))
+    with patch("backend.nodes.image_demo.DEMO_DIR", FIXTURES):
+        ExecutionEngine().execute(
+            {"1": {"class_type": "ImageDemo", "inputs": {"name": "Bacteria.ibw", "colormap": "viridis"}}},
+            on_preview=lambda node_id, payload: previews.append((node_id, payload)),
+        )
 
     assert len(previews) == 1
     node_id, payload = previews[0]