fix file selection & test

src/affinder/_tests/test_affinder.py

@@ -139,17 +139,17 @@ def test_apply_affine_nonimage():
         widget(ref_layer, mov_layer)
 
 
-def test_load_affine():
-    existing_affine = np.array([[0.9, 0.1, 5], [0.4, 0.2, 9], [0, 0, 1]])
+def test_load_affine(tmp_path):
+    affile = tmp_path / 'test_affine.txt'
+    affine = np.array([[2, 0, 5], [0, 2, 5], [0, 0, 1]])
+    np.savetxt(affile, affine, delimiter=',')
 
     layer = napari.layers.Image(np.random.random((5, 5)))
-    layer.affine = existing_affine
 
-    widget = load_affine(,
-    widget(layer, './src/affinder/_tests/load_test/2d_test_affine.txt')
+    widget = load_affine()
+    widget(layer, affile)
+
     np.testing.assert_allclose(
-            layer.affine,
-            np.loadtxt('./src/affinder/_tests/load_test/2d_test_affine.txt',
-                       delimiter=',') @ existing_affine
-            )
+        layer.affine, affine
+    )
 

src/affinder/load_tf.py

@@ -1,10 +1,12 @@
+from pathlib import Path
+
 import numpy as np
 from magicgui import magic_factory
 from napari.layers import Layer
 
 
-@magic_factory(call_button='Load')
-def load_affine(layer: Layer, affine: str):
+@magic_factory(call_button='Load', affine={'mode': 'r'})
+def load_affine(layer: Layer, affine: Path):
     """Load affine from string.
 
     Parameters
@@ -15,4 +17,4 @@ def load_affine(layer: Layer, affine: str):
         Affine to load.
     """
     affine = np.loadtxt(affine, delimiter=',')
-    layer.affine = affine @ layer.affine
+    layer.affine = affine