Implement a test for setting the geometry

test/cmake/Basics.cmake

@@ -241,9 +241,9 @@ add_python_test(
 
 add_python_test(
     NAME "Core sets geometry at runtime"
-    TEST_MODULE ""
-    DISABLED
-) # TODO: Implement this test
+    TEST_MODULE basics.core_sets_geometry
+    CONTENT "${NDS_ROM}"
+)
 
 add_python_test(
     NAME "Core registers support for achievements"

test/python/basics/core_sets_geometry.py

@@ -0,0 +1,77 @@
+import itertools
+from typing import cast
+
+from libretro import Session
+from libretro.api.input import JoypadState
+from libretro.api.video import PillowVideoDriver
+
+import prelude
+
+options = {
+    b"melonds_number_of_screen_layouts": b"2",
+    b"melonds_screen_layout1": b"top-bottom",
+    b"melonds_screen_layout2": b"left-right",
+}
+
+
+def generate_input():
+    # Wait a little while...
+    yield from itertools.repeat(None, 10)
+
+    # Cycle to the next screen layout
+    yield JoypadState(r2=True)
+
+    yield from itertools.repeat(None)
+
+
+session: Session
+with prelude.session(input_state=generate_input) as session:
+    video = cast(PillowVideoDriver, session.video)
+    for i in range(10):
+        session.core.run()
+
+    frame1 = video.get_frame()
+    framebuffer1 = video.get_frame_max()
+    geometry1 = video.geometry
+
+    assert frame1 is not None
+    assert framebuffer1 is not None
+    assert geometry1 is not None
+
+    assert frame1.size != framebuffer1.size, \
+        f"Frame size should not be the same as framebuffer size ({frame1.size})"
+
+    assert frame1.width < framebuffer1.width, \
+        f"Frame width ({frame1.width}) shouldn't exceed framebuffer width ({framebuffer1.width})"
+
+    assert frame1.height < framebuffer1.height, \
+        f"Frame height ({frame1.height}) shouldn't exceed framebuffer height ({framebuffer1.height})"
+
+    assert frame1.width == geometry1.base_width, \
+        f"Frame width ({frame1.width}) should match geometry base width ({geometry1.base_width})"
+
+    assert frame1.height == geometry1.base_height, \
+        f"Frame height ({frame1.height}) should match geometry base height ({geometry1.height})"
+
+    assert framebuffer1.width == geometry1.max_width, \
+        f"Framebuffer width ({framebuffer1.width}) should match geometry max width ({geometry1.max_width})"
+
+    assert framebuffer1.height == geometry1.max_height, \
+        f"Framebuffer height ({framebuffer1.height}) should match geometry max height ({geometry1.max_height})"
+
+    for i in range(20):
+        session.core.run()
+
+    # Now that we've changed the screen layout, let's make sure we changed the geometry
+
+    frame2 = video.get_frame()
+    framebuffer2 = video.get_frame_max()
+    geometry2 = video.geometry
+
+    assert frame2 is not None
+    assert framebuffer2 is not None
+    assert geometry2 is not None
+
+    assert geometry1 != geometry2, f"Geometry should have changed from {geometry1} after switching screen layout"
+    assert framebuffer1.size == framebuffer2.size, \
+        f"Framebuffer size changed from {framebuffer1.size} to {framebuffer2.size}, but it shouldn't have"