BUG: Make find_all wait for the element like find does.

botcity/core/bot.py

@@ -493,16 +493,20 @@ def find_same(item, items):
                 return None
 
             haystack = self.get_screenshot()
-            eles = cv2find.locate_all_opencv(
-                element_path,
-                haystack_image=haystack,
-                region=region,
-                confidence=matching,
-                grayscale=grayscale,
+            # locate_all_opencv returns a generator, which is always truthy.
+            # Collect it so an empty result makes us look again.
+            eles = list(
+                cv2find.locate_all_opencv(
+                    element_path,
+                    haystack_image=haystack,
+                    region=region,
+                    confidence=matching,
+                    grayscale=grayscale,
+                )
             )
             if not eles:
                 continue
-            eles = deduplicate(list(eles))
+            eles = deduplicate(eles)
             for ele in eles:
                 if ele is not None:
                     ele = self._fix_retina_element(ele)

botcity/core/tests/test_find_all_wait.py

@@ -0,0 +1,32 @@
+import numpy
+from PIL import Image
+
+from botcity.core import DesktopBot, cv2find
+
+
+def test_find_all_keeps_looking_until_the_element_appears(tmp_path, monkeypatch):
+    rng = numpy.random.default_rng(0)
+    needle = rng.integers(0, 256, (10, 10, 3), dtype=numpy.uint8)
+    empty_screen = rng.integers(0, 256, (100, 200, 3), dtype=numpy.uint8)
+    loaded_screen = empty_screen.copy()
+    loaded_screen[20:30, 40:50] = needle
+    # The element shows up on the third screenshot, well within waiting_time.
+    screens = [empty_screen, empty_screen, loaded_screen]
+
+    needle_path = tmp_path / "needle.png"
+    Image.fromarray(needle).save(needle_path)
+    bot = DesktopBot()
+    bot.add_image("needle", str(needle_path))
+    monkeypatch.setattr(bot, "_fix_display_size", lambda: (200, 100))
+    monkeypatch.setattr(
+        bot,
+        "get_screenshot",
+        lambda *a, **k: Image.fromarray(
+            screens.pop(0) if len(screens) > 1 else screens[0]
+        ),
+    )
+    monkeypatch.setattr("botcity.core.bot.is_retina", lambda: False)
+
+    found = list(bot.find_all("needle", matching=0.9, waiting_time=5000))
+
+    assert found == [cv2find.Box(40, 20, 10, 10)]