test fixes

Author: willmcgugan

CHANGELOG.md

@@ -21,6 +21,7 @@ and this project adheres to [Semantic Versioning](http://semver.org/).
 - Added `screen--selection` component class to define style for selection
 - Added `Widget.scrollable_container` property
 - Added `Widget.select_all`
+- Added `Region.bottom_right_inclusive`
 
 ### Fixed
 

src/textual/_compositor.py

@@ -894,7 +894,7 @@ def get_widget_and_offset_at(
             return None, None
 
         if y >= widget.content_region.bottom:
-            x, y = widget.content_region.bottom_right - (1, 1)
+            x, y = widget.content_region.bottom_right_inclusive
 
         x -= region.x
         y -= region.y

src/textual/geometry.py

@@ -548,6 +548,12 @@ def bottom_right(self) -> Offset:
         x, y, width, height = self
         return Offset(x + width, y + height)
 
+    @property
+    def bottom_right_inclusive(self) -> Offset:
+        """Bottom right corner of the region, within its boundaries."""
+        x, y, width, height = self
+        return Offset(x + width - 1, y + height - 1)
+
     @property
     def size(self) -> Size:
         """Get the size of the region."""

src/textual/screen.py

@@ -1481,15 +1481,6 @@ def _forward_event(self, event: events.Event) -> None:
         if isinstance(event, (events.Enter, events.Leave)):
             self.post_message(event)
 
-        elif isinstance(event, events.MouseUp):
-            if (
-                self._mouse_down_offset is not None
-                and self._mouse_down_offset == event.screen_offset
-            ):
-                self.clear_selection()
-            self._mouse_down_offset = None
-            self._selecting = False
-
         elif isinstance(event, events.MouseMove):
             event.style = self.get_style_at(event.screen_x, event.screen_y)
             self._handle_mouse_move(event)
@@ -1498,15 +1489,29 @@ def _forward_event(self, event: events.Event) -> None:
                 select_widget, select_offset = self.get_widget_and_offset_at(
                     event.x, event.y
                 )
-                if (
+                if self._select_end is not None and select_offset is None:
+                    end_widget = self._select_end[0]
+                    select_offset = end_widget.content_region.bottom_right_inclusive
+                    self._select_end = (end_widget, event.offset, select_offset)
+
+                elif (
                     select_widget is not None
                     and select_widget.allow_select
                     and select_offset is not None
                 ):
                     self._select_end = (select_widget, event.offset, select_offset)
 
         elif isinstance(event, events.MouseEvent):
-            if isinstance(event, events.MouseDown) and not self.app.mouse_captured:
+            if isinstance(event, events.MouseUp):
+                if (
+                    self._mouse_down_offset is not None
+                    and self._mouse_down_offset == event.screen_offset
+                ):
+                    self.clear_selection()
+                self._mouse_down_offset = None
+                self._selecting = False
+
+            elif isinstance(event, events.MouseDown) and not self.app.mouse_captured:
                 self._mouse_down_offset = event.screen_offset
                 select_widget, select_offset = self.get_widget_and_offset_at(
                     event.screen_x, event.screen_y

src/textual/selection.py

@@ -53,10 +53,14 @@ def extract(self, text: str) -> str:
             return lines[start_line][start_offset:end_offset]
 
         selection: list[str] = []
-        first_line, *mid_lines, last_line = lines[start_line:end_line]
-        selection.append(first_line[start_offset:])
-        selection.extend(mid_lines)
-        selection.append(last_line[: end_offset + 1])
+        selected_lines = lines[start_line:end_line]
+        if len(selected_lines) >= 2:
+            first_line, *mid_lines, last_line = selected_lines
+            selection.append(first_line[start_offset:])
+            selection.extend(mid_lines)
+            selection.append(last_line[: end_offset + 1])
+        else:
+            return lines[start_line][start_offset:end_offset]
         return "\n".join(selection)
 
     def get_span(self, y: int) -> tuple[int, int] | None: