Fix content width (#1910)

* fix calculation for scrollbars

* added snapshot

* fix for name change

* snapshot

* fix for textual colors

* remove logs

* scrollbar logic

* scroll logic

* remove dead code

* snapshot tests

* scrollbar mechanism

* tidy

* demo tweak

* preset window size

* no need for repaint

* Restore repaint

* wait for idle on pause

* colors tweak

* remove wait for idle

* snapshot

* small sleep

* change stabilizer

* debug tweaks

* remove debug

* remove debug

* snapshot test

* docstring

* changelog

* add pause

tests/snapshot_tests/snapshot_apps/line_api_scrollbars.py

@@ -0,0 +1,54 @@
+from rich.text import Text
+
+from textual.app import App, ComposeResult
+from textual.containers import Vertical
+from textual.widget import Widget
+from textual.widgets import TextLog
+
+
+class MyWidget(Widget):
+    def render(self):
+        return Text(
+            "\n".join(f"{n} 0123456789" for n in range(20)),
+            no_wrap=True,
+            overflow="hidden",
+            justify="left",
+        )
+
+
+class ScrollViewApp(App):
+    CSS = """
+    Screen {
+        align: center middle;
+    }
+    
+    TextLog {
+        width:13;
+        height:10;        
+    }
+
+    Vertical{
+        width:13;
+        height: 10;
+        overflow: scroll;
+        overflow-x: auto;
+    }
+    MyWidget {
+        width:13;
+        height:auto;
+    }
+
+    """
+
+    def compose(self) -> ComposeResult:
+        yield TextLog()
+        yield Vertical(MyWidget())
+
+    def on_ready(self) -> None:
+        self.query_one(TextLog).write("\n".join(f"{n} 0123456789" for n in range(20)))
+        self.query_one(Vertical).scroll_end(animate=False)
+
+
+if __name__ == "__main__":
+    app = ScrollViewApp()
+    app.run()

tests/snapshot_tests/test_snapshots.py

@@ -256,3 +256,7 @@ def test_disabled_widgets(snap_compare):
 
 def test_focus_component_class(snap_compare):
     assert snap_compare(SNAPSHOT_APPS_DIR / "focus_component_class.py", press=["tab"])
+
+
+def test_line_api_scrollbars(snap_compare):
+    assert snap_compare(SNAPSHOT_APPS_DIR / "line_api_scrollbars.py", press=["_"])

tests/tree/test_tree_messages.py

@@ -46,6 +46,7 @@ async def test_tree_node_selected_message() -> None:
     """Selecting a node should result in a selected message being emitted."""
     async with TreeApp().run_test() as pilot:
         await pilot.press("enter")
+        await pilot.pause()
         assert pilot.app.messages == ["NodeExpanded", "NodeSelected"]
 
 
@@ -54,6 +55,7 @@ async def test_tree_node_selected_message_no_auto() -> None:
     async with TreeApp().run_test() as pilot:
         pilot.app.query_one(MyTree).auto_expand = False
         await pilot.press("enter")
+        await pilot.pause()
         assert pilot.app.messages == ["NodeSelected"]
 
 
@@ -61,6 +63,7 @@ async def test_tree_node_expanded_message() -> None:
     """Expanding a node should result in an expanded message being emitted."""
     async with TreeApp().run_test() as pilot:
         await pilot.press("space")
+        await pilot.pause()
         assert pilot.app.messages == ["NodeExpanded"]
 
 
@@ -68,6 +71,7 @@ async def test_tree_node_collapsed_message() -> None:
     """Collapsing a node should result in a collapsed message being emitted."""
     async with TreeApp().run_test() as pilot:
         await pilot.press("space", "space")
+        await pilot.pause()
         assert pilot.app.messages == ["NodeExpanded", "NodeCollapsed"]
 
 
@@ -75,4 +79,5 @@ async def test_tree_node_highlighted_message() -> None:
     """Highlighting a node should result in a highlighted message being emitted."""
     async with TreeApp().run_test() as pilot:
         await pilot.press("enter", "down")
+        await pilot.pause()
         assert pilot.app.messages == ["NodeExpanded", "NodeSelected", "NodeHighlighted"]