fix: pass (width, height) to Pillow in the Resize transform (#697)

* fix: pass (width, height) to Pillow in the Resize transform

`resize()` handed a tuple size straight to `PIL.Image.resize()`. fastembed
keeps sizes as (height, width) — `Transform.from_config` builds the tuple
as `(size["height"], size["width"])` — while Pillow takes (width, height),
so a non-square image processor configuration produced a transposed image:

    Resize(size=(100, 200))(Image.new("RGB", (300, 300)))[0].size
    # (100, 200), expected (200, 100)

Square sizes are unaffected, which is why this went unnoticed. The int
branch of `resize()` already emits Pillow order and is untouched, as are
`resize_ndarray()`'s callers, which pass (width, height) explicitly.

`Resize.__call__` is the only caller of this function and always supplies
fastembed's height-first order, so converting here is safe.

Co-Authored-By: Claude Opus 5 <noreply@anthropic.com>

* tests: simplify tests

---------

Co-authored-by: George Panchuk <george.panchuk@qdrant.tech>

fastembed/image/transform/functional.py

@@ -98,7 +98,12 @@ def resize(
     resample: int | Image.Resampling = Image.Resampling.BILINEAR,
 ) -> Image.Image:
     if isinstance(size, tuple):
-        return image.resize(size, resample)
+        # fastembed keeps sizes as (height, width) — `Compose.from_config` builds the
+        # tuple as (size["height"], size["width"]) — while Pillow's resize takes
+        # (width, height). The two agree for square sizes, so this only shows up on a
+        # non-square image processor configuration.
+        height, width = size
+        return image.resize((width, height), resample)
 
     height, width = image.height, image.width
     short, long = (width, height) if width <= height else (height, width)

tests/test_image_transform.py

@@ -0,0 +1,28 @@
+import pytest
+from PIL import Image
+
+from fastembed.image.transform.functional import resize
+
+
+@pytest.mark.parametrize(
+    ("size", "expected"),
+    [
+        ((100, 200), (200, 100)),  # the bug: a non-square size came back transposed
+        ((224, 224), (224, 224)),  # the square path every shipped model takes
+    ],
+)
+def test_resize_tuple_is_height_width(size: tuple[int, int], expected: tuple[int, int]) -> None:
+    """A ``(height, width)`` size must reach Pillow as ``(width, height)``."""
+    resized = resize(Image.new("RGB", (300, 300)), size=size)
+
+    assert resized.size == expected  # PIL reports (width, height)
+
+
+def test_resize_int_keeps_shortest_edge_behaviour() -> None:
+    """The int branch already emitted Pillow order; it must not be disturbed."""
+    landscape = Image.new("RGB", (400, 200))
+    portrait = Image.new("RGB", (200, 400))
+
+    # size sets the shortest edge, and the aspect ratio is preserved.
+    assert resize(landscape, size=100).size == (200, 100)
+    assert resize(portrait, size=100).size == (100, 200)