Merge pull request #2484 from pygame-community/sdl_mouse_touch

Use SDL_MOUSE_TOUCH_EVENTS in touch test and docs

Author: zoldalma999

docs/reST/ref/pygame.rst

@@ -535,3 +535,15 @@ By default, when the window is not in focus, input devices do not get
 updated. However, using this environment variable it is possible to get
 joystick updates even when the window is in the background. Must be set
 before calling :func:`pygame.init()` or :func:`pygame.joystick.init()`.
+
+|
+
+::
+
+ SDL_MOUSE_TOUCH_EVENTS
+ Set to "1" to make mouse events also generate touch events.
+
+Useful for testing touch events on desktop platforms (e.g. with a trackpad)
+where this is set to 0 by default.
+
+

test/touch_test.py

@@ -5,32 +5,33 @@
 from pygame.tests.test_utils import question
 
 
-has_touchdevice = touch.get_num_devices() > 0
-
-
 class TouchTest(unittest.TestCase):
     @classmethod
     def setUpClass(cls):
-        pygame.display.init()
+        os.environ["SDL_MOUSE_TOUCH_EVENTS"] = "0"
+        pygame.init()
 
     @classmethod
     def tearDownClass(cls):
-        pygame.display.quit()
+        pygame.quit()
 
     def test_num_devices(self):
         touch.get_num_devices()
 
-    @unittest.skipIf(not has_touchdevice, "no touch devices found")
     def test_get_device(self):
-        touch.get_device(0)
+        if touch.get_num_devices() > 0:
+            touch.get_device(0)
 
     def test_get_device__invalid(self):
         self.assertRaises(pygame.error, touch.get_device, -1234)
         self.assertRaises(TypeError, touch.get_device, "test")
 
-    @unittest.skipIf(not has_touchdevice, "no touch devices found")
     def test_num_fingers(self):
-        touch.get_num_fingers(touch.get_device(0))
+        if touch.get_num_devices() > 0:
+            if touch.get_device(0) >= 0:
+                # mice acting as touch devices have negative device IDs
+                # they also do not work with get_num_fingers()
+                touch.get_num_fingers(touch.get_device(0))
 
     def test_num_fingers__invalid(self):
         self.assertRaises(TypeError, touch.get_num_fingers, "test")
@@ -40,15 +41,26 @@ def test_num_fingers__invalid(self):
 class TouchInteractiveTest(unittest.TestCase):
     __tags__ = ["interactive"]
 
-    @unittest.skipIf(not has_touchdevice, "no touch devices found")
+    @classmethod
+    def setUpClass(cls):
+        # if we don't have a touch device, enable the mouse to act as a
+        # touch device for the interactive tests.
+        os.environ["SDL_MOUSE_TOUCH_EVENTS"] = "0"
+        pygame.init()
+        if touch.get_num_devices() == 0:
+            pygame.quit()
+            os.environ["SDL_MOUSE_TOUCH_EVENTS"] = "1"
+            pygame.init()
+
+    @classmethod
+    def tearDownClass(cls):
+        pygame.quit()
+
     def test_get_finger(self):
         """ask for touch input and check the dict"""
 
-        pygame.display.init()
-        pygame.font.init()
-
         os.environ["SDL_VIDEO_WINDOW_POS"] = "50,50"
-        screen = pygame.display.set_mode((800, 600))
+        screen = pygame.display.set_mode((1000, 600))
         screen.fill((255, 255, 255))
 
         font = pygame.font.Font(None, 32)
@@ -69,7 +81,10 @@ def test_get_finger(self):
             num_devices = pygame._sdl2.touch.get_num_devices()
             if num_devices > 0:
                 first_device = pygame._sdl2.touch.get_device(0)
-                num_fingers = pygame._sdl2.touch.get_num_fingers(first_device)
+                if first_device >= 0:
+                    num_fingers = pygame._sdl2.touch.get_num_fingers(first_device)
+                else:
+                    num_fingers = 1
                 if num_fingers > 0:
                     for finger_index in range(0, num_fingers):
                         data = pygame._sdl2.touch.get_finger(first_device, finger_index)
@@ -90,8 +105,6 @@ def test_get_finger(self):
         response = question("Does the finger data seem correct?")
         self.assertTrue(response)
 
-        pygame.display.quit()
-
 
 if __name__ == "__main__":
     unittest.main()