fix: mouseDrag diagonally

move mouse diagonally instead of first going up/down and then
left/right.

Do not use `time.sleep()` with Twisted reactor as it will also pause all
other event processing.

Patch `vncev` to print all mouse events, including those where not button
is pressed / released.

Issue sibson#287

CHANGELOG.rst

@@ -4,6 +4,7 @@
   - Python 3.12 is supported (@phahn)
   - Improve documentation (@phahn)
   - Improve PEP-484 type hinting (@phahn)
+  - Fix mouse dragging (@phahn)
 
 1.2.0 (2023-06-06)
 ----------------------

libvncserver.mk

@@ -35,6 +35,7 @@ $(BUILD_DIR)/$(LIBVNCSERVER_TGZ):
 
 $(LIBVNCSERVER_DIR): $(BUILD_DIR)/$(LIBVNCSERVER_TGZ)
 	tar xfzv $< -C $(BUILD_DIR)
+	sed -e '/^\s*if(buttonMask)\s*{$/s/buttonMask/1/' -i "$(LIBVNCSERVER_DIR)/examples/vncev.c"
 
 $(LIBVNCSERVER_MAKEFILE): $(LIBVNCSERVER_MAKEFILE_SRCS)
 	cd $(LIBVNCSERVER_DIR) && cmake .

tests/functional/test_send_events.py

@@ -65,11 +65,17 @@ def test_type(self) -> None:
         self.assertDisconnect()
 
     def test_mouse_move(self) -> None:
-        # vncev only prints click events, but will include the position
         self.run_vncdo('move 10 20 click 1')
         self.assertMouse(10, 20, 0x1)
         self.assertDisconnect()
 
+    def test_mouse_drag(self) -> None:
+        self.run_vncdo('move 10 20 drag 30 30 click 1')
+        self.assertMouse(10, 20, 0x0)
+        self.assertMouse(20, 25, 0x0)
+        self.assertMouse(30, 30, 0x1)
+        self.assertDisconnect()
+
     def test_mouse_click_button_two(self) -> None:
         self.run_vncdo('click 2')
         self.assertMouse(0, 0, 0x2)

vncdotool/client.py

@@ -10,13 +10,12 @@
 import logging
 import math
 import socket
-import time
 from pathlib import Path
 from struct import pack
-from typing import IO, Any, TypeVar, Union
+from typing import IO, Any, Iterator, TypeVar, Union
 
 from twisted.internet import reactor
-from twisted.internet.defer import Deferred
+from twisted.internet.defer import Deferred, inlineCallbacks, returnValue
 from twisted.internet.endpoints import HostnameEndpoint, UNIXClientEndpoint
 from twisted.internet.interfaces import IConnector, ITCPTransport
 from twisted.python.failure import Failure
@@ -346,32 +345,20 @@ def mouseMove(self: TClient, x: int, y: int) -> TClient:
         self.pointerEvent(x, y, self.buttons)
         return self
 
-    def mouseDrag(self: TClient, x: int, y: int, step: int = 1) -> TClient:
+    @inlineCallbacks
+    def mouseDrag(self: TClient, x: int, y: int, step: int = 1) -> Iterator[Deferred]:
         """Move the mouse point to position (x, y) in increments of step"""
         log.debug("mouseDrag %d,%d", x, y)
-        if x < self.x:
-            xsteps = range(self.x - step, x, -step)
-        else:
-            xsteps = range(self.x + step, x, step)
-
-        if y < self.y:
-            ysteps = range(self.y - step, y, -step)
-        else:
-            ysteps = range(self.y + step, y, step)
-
-        for ypos in ysteps:
-            self.mouseMove(self.x, ypos)
-            reactor.doPoll(timeout=5)
-            time.sleep(0.2)
-
-        for xpos in xsteps:
-            self.mouseMove(xpos, self.y)
-            reactor.doPoll(timeout=5)
-            time.sleep(0.2)
+        ox, oy = self.x, self.y
+        dx, dy = x - ox, y - oy
+        dmax = max(abs(dx), abs(dy))
+        for s in range(0, dmax, step):
+            self.mouseMove(ox + dx * s // dmax, oy + dy * s // dmax)
+            yield self.pause(0.2)
 
         self.mouseMove(x, y)
 
-        return self
+        returnValue(self)
 
     def setImageMode(self) -> None:
         """Check support for PixelFormats announced by server or select client supported alternative."""