Add basic event queue tests

Break tcod.event, tcod.context cycle

Author: HexDecimal

.vscode/settings.json

@@ -20,6 +20,7 @@
         "aarch",
         "ADDA",
         "ADDALPHA",
+        "ADDEVENT",
         "addoption",
         "addopts",
         "addressof",

tcod/context.py

@@ -68,7 +68,7 @@
     "new_window",
 )
 
-_Event = TypeVar("_Event", bound=tcod.event.Event)
+_Event = TypeVar("_Event", bound="tcod.event.Event")
 
 SDL_WINDOW_FULLSCREEN = lib.SDL_WINDOW_FULLSCREEN
 """Fullscreen mode."""

tests/test_event.py

@@ -0,0 +1,73 @@
+"""Tests for event parsing and handling."""
+
+from typing import Any, Final
+
+import pytest
+
+import tcod.event
+import tcod.sdl.sys
+from tcod._internal import _check
+from tcod.cffi import ffi, lib
+from tcod.event import KeySym, Modifier, Scancode
+
+EXPECTED_EVENTS: Final = (
+    tcod.event.Quit(),
+    tcod.event.KeyDown(scancode=Scancode.A, sym=KeySym.A, mod=Modifier(0), pressed=True),
+    tcod.event.KeyUp(scancode=Scancode.A, sym=KeySym.A, mod=Modifier(0), pressed=False),
+)
+"""Events to compare with after passing though the SDL event queue."""
+
+
+def as_sdl_event(event: tcod.event.Event) -> dict[str, dict[str, Any]]:
+    """Convert events into SDL_Event unions using cffi's union format."""
+    match event:
+        case tcod.event.Quit():
+            return {"quit": {"type": lib.SDL_EVENT_QUIT}}
+        case tcod.event.KeyboardEvent():
+            return {
+                "key": {
+                    "type": (lib.SDL_EVENT_KEY_UP, lib.SDL_EVENT_KEY_DOWN)[event.pressed],
+                    "scancode": event.scancode,
+                    "key": event.sym,
+                    "mod": event.mod,
+                    "down": event.pressed,
+                    "repeat": event.repeat,
+                }
+            }
+    raise AssertionError
+
+
+EVENT_PACK: Final = ffi.new("SDL_Event[]", [as_sdl_event(_e) for _e in EXPECTED_EVENTS])
+"""A custom C array of SDL_Event unions based on EXPECTED_EVENTS."""
+
+
+def push_events() -> None:
+    """Reset the SDL event queue to an expected list of events."""
+    tcod.sdl.sys.init(tcod.sdl.sys.Subsystem.EVENTS)  # Ensure SDL event queue is enabled
+
+    lib.SDL_PumpEvents()  # Clear everything from the queue
+    lib.SDL_FlushEvents(lib.SDL_EVENT_FIRST, lib.SDL_EVENT_LAST)
+
+    assert _check(  # Fill the queue with EVENT_PACK
+        lib.SDL_PeepEvents(EVENT_PACK, len(EVENT_PACK), lib.SDL_ADDEVENT, lib.SDL_EVENT_FIRST, lib.SDL_EVENT_LAST)
+    ) == len(EVENT_PACK)
+
+
+def test_get_events() -> None:
+    push_events()
+    assert tuple(tcod.event.get()) == EXPECTED_EVENTS
+
+    assert tuple(tcod.event.get()) == ()
+    assert tuple(tcod.event.wait(timeout=0)) == ()
+
+    push_events()
+    assert tuple(tcod.event.wait()) == EXPECTED_EVENTS
+
+
+def test_event_dispatch() -> None:
+    push_events()
+    with pytest.deprecated_call():
+        tcod.event.EventDispatch().event_wait(timeout=0)
+    push_events()
+    with pytest.deprecated_call():
+        tcod.event.EventDispatch().event_get()