Merge branch 'main' into tree-lines-fix

CHANGELOG.md

@@ -7,6 +7,12 @@ and this project adheres to [Semantic Versioning](http://semver.org/).
 
 ## Unreleased
 
+### Changed
+
+- The DataTable cursor is now scrolled into view when the cursor coordinate is changed programmatically https://github.com/Textualize/textual/issues/2459
+
+## [0.23.0] - 2023-05-03
+
 ### Fixed
 
 - Fixed `outline` top and bottom not handling alpha - https://github.com/Textualize/textual/issues/2371
@@ -21,11 +27,17 @@ and this project adheres to [Semantic Versioning](http://semver.org/).
 ### Changed
 
 - Setting attributes with a `compute_` method will now raise an `AttributeError` https://github.com/Textualize/textual/issues/2383
+- Unknown psuedo-selectors will now raise a tokenizer error (previously they were silently ignored) https://github.com/Textualize/textual/pull/2445
+- Breaking change: `DirectoryTree.FileSelected.path` is now always a `Path` https://github.com/Textualize/textual/issues/2448
+- Breaking change: `Directorytree.load_directory` renamed to `Directorytree._load_directory` https://github.com/Textualize/textual/issues/2448
 - Unknown pseudo-selectors will now raise a tokenizer error (previously they were silently ignored) https://github.com/Textualize/textual/pull/2445
 
 ### Added
 
 - Watch methods can now optionally be private https://github.com/Textualize/textual/issues/2382
+- Added `DirectoryTree.path` reactive attribute https://github.com/Textualize/textual/issues/2448
+- Added `DirectoryTree.FileSelected.node` https://github.com/Textualize/textual/pull/2463
+- Added `DirectoryTree.reload` https://github.com/Textualize/textual/issues/2448
 - Added textual.on decorator https://github.com/Textualize/textual/issues/2398
 
 ## [0.22.3] - 2023-04-29
@@ -867,6 +879,7 @@ https://textual.textualize.io/blog/2022/11/08/version-040/#version-040
 - New handler system for messages that doesn't require inheritance
 - Improved traceback handling
 
+[0.23.0]: https://github.com/Textualize/textual/compare/v0.22.3...v0.23.0
 [0.22.3]: https://github.com/Textualize/textual/compare/v0.22.2...v0.22.3
 [0.22.2]: https://github.com/Textualize/textual/compare/v0.22.1...v0.22.2
 [0.22.1]: https://github.com/Textualize/textual/compare/v0.22.0...v0.22.1

docs/blog/posts/release0-23-0.md

@@ -0,0 +1,88 @@
+---
+draft: false
+date: 2023-05-03
+categories:
+  - Release
+title: "Textual 0.23.0 improves message handling"
+authors:
+  - willmcgugan
+---
+
+# Textual 0.23.0 improves message handling
+
+It's been a busy couple of weeks at Textualize.
+We've been building apps with [Textual](https://github.com/Textualize/textual), as part of our *dog-fooding* week.
+The first app, [Frogmouth](https://github.com/Textualize/frogmouth), was released at the weekend and already has 1K GitHub stars!
+Expect two more such apps this month.
+
+<!-- more -->
+
+<div>
+--8<-- "docs/blog/images/frogmouth.svg"
+</div>
+
+!!! tip
+
+    Join our [mailing list](http://eepurl.com/hL0BF1) if you would like to be the first to hear about our apps.
+
+We haven't stopped developing Textual in that time.
+Today we released version 0.23.0 which has a really interesting API update I'd like to introduce.
+
+Textual *widgets* can send messages to each other.
+To respond to those messages, you implement a message handler with a naming convention.
+For instance, the [Button](/widget_gallery/#button) widget sends a `Pressed` event.
+To handle that event, you implement a method called `on_button_pressed`.
+
+Simple enough, but handler methods are called to handle pressed events from *all* Buttons.
+To manage multiple buttons you typically had to write a large `if` statement to wire up each button to the code it should run.
+It didn't take many Buttons before the handler became hard to follow.
+
+## On decorator
+
+Version 0.23.0 introduces the [`@on`](/guide/events/#on-decorator) decorator which allows you to dispatch events based on the widget that initiated them.
+
+This is probably best explained in code.
+The following two listings respond to buttons being pressed.
+The first uses a single message handler, the second uses the decorator approach:
+
+=== "on_decorator01.py"
+
+    ```python title="on_decorator01.py"
+    --8<-- "docs/examples/events/on_decorator01.py"
+    ```
+
+    1. The message handler is called when any button is pressed
+
+=== "on_decorator02.py"
+
+    ```python title="on_decorator02.py"
+    --8<-- "docs/examples/events/on_decorator02.py"
+    ```
+
+    1. Matches the button with an id of "bell" (note the `#` to match the id)
+    2. Matches the button with class names "toggle" *and* "dark"
+    3. Matches the button with an id of "quit"
+
+=== "Output"
+
+    ```{.textual path="docs/examples/events/on_decorator01.py"}
+    ```
+
+The decorator dispatches events based on a CSS selector.
+This means that you could have a handler per button, or a handler for buttons with a shared class, or parent.
+
+We think this is a very flexible mechanism that will help keep code readable and maintainable.
+
+## Why didn't we do this earlier?
+
+It's a reasonable question to ask: why didn't we implement this in an earlier version?
+We were certainly aware there was a deficiency in the API.
+
+The truth is simply that we didn't have an elegant solution in mind until recently.
+The `@on` decorator is, I believe, an elegant and powerful mechanism for dispatching handlers.
+It might seem obvious in hindsight, but it took many iterations and brainstorming in the office to come up with it!
+
+
+## Join us
+
+If you want to talk about this update or anything else Textual related, join us on our [Discord server](https://discord.gg/Enf6Z3qhVr).

docs/examples/events/on_decorator01.py

@@ -12,7 +12,7 @@ class OnDecoratorApp(App):
         yield Button("Toggle dark", classes="toggle dark")
         yield Button("Quit", id="quit")
 
-    def on_button_pressed(self, event: Button.Pressed) -> None:
+    def on_button_pressed(self, event: Button.Pressed) -> None:  # (1)!
         """Handle all button pressed events."""
         if event.button.id == "bell":
             self.bell()

docs/guide/events.md

@@ -181,6 +181,8 @@ In the following example we have three buttons, each of which does something dif
     --8<-- "docs/examples/events/on_decorator01.py"
     ```
 
+    1. The message handler is called when any button is pressed
+
 === "Output"
 
     ```{.textual path="docs/examples/events/on_decorator01.py"}

pyproject.toml

@@ -1,6 +1,6 @@
 [tool.poetry]
 name = "textual"
-version = "0.22.3"
+version = "0.23.0"
 homepage = "https://github.com/Textualize/textual"
 description = "Modern Text User Interface framework"
 authors = ["Will McGugan <will@textualize.io>"]

src/textual/app.py

@@ -1253,6 +1253,7 @@ class App(Generic[ReturnType], DOMNode):
         will be added, and this method is called to apply the corresponding
         :hover styles.
         """
+
         descendants = node.walk_children(with_self=True)
         self.stylesheet.update_nodes(descendants, animate=True)
 

src/textual/cli/previews/borders.py

@@ -1,5 +1,5 @@
 from textual.app import App, ComposeResult
-from textual.containers import VerticalScroll
+from textual.containers import Vertical
 from textual.css.constants import VALID_BORDER
 from textual.widgets import Button, Label
 
@@ -12,7 +12,7 @@ And when it has gone past, I will turn the inner eye to see its path.
 Where the fear has gone there will be nothing. Only I will remain."""
 
 
-class BorderButtons(VerticalScroll):
+class BorderButtons(Vertical):
     DEFAULT_CSS = """
     BorderButtons {
         dock: left;

src/textual/cli/previews/colors.py

@@ -1,5 +1,5 @@
 from textual.app import App, ComposeResult
-from textual.containers import Horizontal, VerticalScroll
+from textual.containers import Horizontal, Vertical, VerticalScroll
 from textual.design import ColorSystem
 from textual.widget import Widget
 from textual.widgets import Button, Footer, Label, Static
@@ -20,11 +20,11 @@ class ColorItem(Horizontal):
     pass
 
 
-class ColorGroup(VerticalScroll):
+class ColorGroup(Vertical):
     pass
 
 
-class Content(VerticalScroll):
+class Content(Vertical):
     pass
 
 

src/textual/cli/previews/easing.py

@@ -5,7 +5,7 @@ from rich.console import RenderableType
 from textual._easing import EASING
 from textual.app import App, ComposeResult
 from textual.cli.previews.borders import TEXT
-from textual.containers import Container, Horizontal, VerticalScroll
+from textual.containers import Horizontal, Vertical
 from textual.reactive import reactive, var
 from textual.scrollbar import ScrollBarRender
 from textual.widget import Widget
@@ -72,13 +72,13 @@ class EasingApp(App):
         )
 
         yield EasingButtons()
-        with VerticalScroll():
+        with Vertical():
             with Horizontal(id="inputs"):
                 yield Label("Animation Duration:", id="label")
                 yield duration_input
             with Horizontal():
                 yield self.animated_bar
-                yield VerticalScroll(self.opacity_widget, id="other")
+                yield Vertical(self.opacity_widget, id="other")
             yield Footer()
 
     def on_button_pressed(self, event: Button.Pressed) -> None:

src/textual/screen.py

@@ -31,6 +31,7 @@ from .binding import Binding
 from .css.match import match
 from .css.parse import parse_selectors
 from .css.query import QueryType
+from .dom import DOMNode
 from .geometry import Offset, Region, Size
 from .reactive import Reactive
 from .renderables.background_screen import BackgroundScreen
@@ -404,6 +405,32 @@ class Screen(Generic[ScreenResultType], Widget):
         # Go with the what was found.
         self.set_focus(chosen)
 
+    def _update_focus_styles(
+        self, focused: Widget | None = None, blurred: Widget | None = None
+    ) -> None:
+        """Update CSS for focus changes.
+
+        Args:
+            focused: The widget that was focused.
+            blurred: The widget that was blurred.
+        """
+        widgets: set[DOMNode] = set()
+
+        if focused is not None:
+            for widget in reversed(focused.ancestors_with_self):
+                if widget._has_focus_within:
+                    widgets.update(widget.walk_children(with_self=True))
+                    break
+        if blurred is not None:
+            for widget in reversed(blurred.ancestors_with_self):
+                if widget._has_focus_within:
+                    widgets.update(widget.walk_children(with_self=True))
+                    break
+        if widgets:
+            self.app.stylesheet.update_nodes(
+                [widget for widget in widgets if widget._has_focus_within], animate=True
+            )
+
     def set_focus(self, widget: Widget | None, scroll_visible: bool = True) -> None:
         """Focus (or un-focus) a widget. A focused widget will receive key events first.
 
@@ -415,25 +442,35 @@ class Screen(Generic[ScreenResultType], Widget):
             # Widget is already focused
             return
 
+        focused: Widget | None = None
+        blurred: Widget | None = None
+
         if widget is None:
             # No focus, so blur currently focused widget if it exists
             if self.focused is not None:
                 self.focused.post_message(events.Blur())
                 self.focused = None
+                blurred = self.focused
             self.log.debug("focus was removed")
         elif widget.focusable:
             if self.focused != widget:
                 if self.focused is not None:
                     # Blur currently focused widget
                     self.focused.post_message(events.Blur())
+                    blurred = self.focused
                 # Change focus
                 self.focused = widget
                 # Send focus event
                 if scroll_visible:
                     self.screen.scroll_to_widget(widget)
                 widget.post_message(events.Focus())
+                focused = widget
+
+                self._update_focus_styles(self.focused, widget)
                 self.log.debug(widget, "was focused")
 
+        self._update_focus_styles(focused, blurred)
+
     async def _on_idle(self, event: events.Idle) -> None:
         # Check for any widgets marked as 'dirty' (needs a repaint)
         event.prevent_default()

src/textual/widget.py

@@ -3077,21 +3077,11 @@ class Widget(DOMNode):
     def _on_focus(self, event: events.Focus) -> None:
         self.has_focus = True
         self.refresh()
-        for widget in reversed(self.ancestors_with_self):
-            if widget._has_focus_within:
-                widget._update_styles()
-                break
-
         self.post_message(events.DescendantFocus())
 
     def _on_blur(self, event: events.Blur) -> None:
         self.has_focus = False
         self.refresh()
-        for widget in reversed(self.ancestors_with_self):
-            if widget._has_focus_within:
-                widget._update_styles()
-                break
-
         self.post_message(events.DescendantBlur())
 
     def _on_mouse_scroll_down(self, event: events.MouseScrollDown) -> None:

src/textual/widgets/_data_table.py

@@ -950,6 +950,7 @@ class DataTable(ScrollView, Generic[CellType], can_focus=True):
             elif self.cursor_type == "column":
                 self.refresh_column(old_coordinate.column)
                 self._highlight_column(new_coordinate.column)
+            self._scroll_cursor_into_view()
 
     def _highlight_coordinate(self, coordinate: Coordinate) -> None:
         """Apply highlighting to the cell at the coordinate, and post event."""

src/textual/widgets/_directory_tree.py

@@ -1,6 +1,5 @@
 from __future__ import annotations
 
-import os
 from dataclasses import dataclass
 from pathlib import Path
 from typing import ClassVar, Iterable
@@ -10,6 +9,7 @@ from rich.text import Text, TextType
 
 from ..events import Mount
 from ..message import Message
+from ..reactive import var
 from ._tree import TOGGLE_STYLE, Tree, TreeNode
 
 
@@ -17,26 +17,19 @@ from ._tree import TOGGLE_STYLE, Tree, TreeNode
 class DirEntry:
     """Attaches directory information to a node."""
 
-    path: str
+    path: Path
-    is_dir: bool
+    """The path of the directory entry."""
     loaded: bool = False
+    """Has this been loaded?"""
 
 
 class DirectoryTree(Tree[DirEntry]):
-    """A Tree widget that presents files and directories.
+    """A Tree widget that presents files and directories."""
-
-    Args:
-        path: Path to directory.
-        name: The name of the widget, or None for no name.
-        id: The ID of the widget in the DOM, or None for no ID.
-        classes: A space-separated list of classes, or None for no classes.
-        disabled: Whether the directory tree is disabled or not.
-    """
 
     COMPONENT_CLASSES: ClassVar[set[str]] = {
-        "directory-tree--folder",
-        "directory-tree--file",
         "directory-tree--extension",
+        "directory-tree--file",
+        "directory-tree--folder",
         "directory-tree--hidden",
     }
     """
@@ -55,10 +48,6 @@ class DirectoryTree(Tree[DirEntry]):
         text-style: bold;
     }
 
-    DirectoryTree > .directory-tree--file {
-
-    }
-
     DirectoryTree > .directory-tree--extension {
         text-style: italic;
     }
@@ -73,14 +62,28 @@ class DirectoryTree(Tree[DirEntry]):
 
         Can be handled using `on_directory_tree_file_selected` in a subclass of
         `DirectoryTree` or in a parent widget in the DOM.
-
-        Attributes:
-            path: The path of the file that was selected.
         """
 
-        def __init__(self, path: str) -> None:
+        def __init__(self, node: TreeNode[DirEntry], path: Path) -> None:
-            self.path: str = path
+            """Initialise the FileSelected object.
+
+            Args:
+                node: The tree node for the file that was selected.
+                path: The path of the file that was selected.
+            """
             super().__init__()
+            self.node: TreeNode[DirEntry] = node
+            """The tree node of the file that was selected."""
+            self.path: Path = path
+            """The path of the file that was selected."""
+
+    path: var[str | Path] = var["str | Path"](Path("."), init=False)
+    """The path that is the root of the directory tree.
+
+    Note:
+        This can be set to either a `str` or a `pathlib.Path` object, but
+        the value will always be a `pathlib.Path` object.
+    """
 
     def __init__(
         self,
@@ -91,18 +94,54 @@ class DirectoryTree(Tree[DirEntry]):
         classes: str | None = None,
         disabled: bool = False,
     ) -> None:
-        str_path = os.fspath(path)
+        """Initialise the directory tree.
-        self.path = str_path
+
+        Args:
+            path: Path to directory.
+            name: The name of the widget, or None for no name.
+            id: The ID of the widget in the DOM, or None for no ID.
+            classes: A space-separated list of classes, or None for no classes.
+            disabled: Whether the directory tree is disabled or not.
+        """
+        self.path = path
         super().__init__(
-            str_path,
+            str(path),
-            data=DirEntry(str_path, True),
+            data=DirEntry(Path(path)),
             name=name,
             id=id,
             classes=classes,
             disabled=disabled,
         )
 
-    def process_label(self, label: TextType):
+    def reload(self) -> None:
+        """Reload the `DirectoryTree` contents."""
+        self.reset(str(self.path), DirEntry(Path(self.path)))
+        self._load_directory(self.root)
+
+    def validate_path(self, path: str | Path) -> Path:
+        """Ensure that the path is of the `Path` type.
+
+        Args:
+            path: The path to validate.
+
+        Returns:
+            The validated Path value.
+
+        Note:
+            The result will always be a Python `Path` object, regardless of
+            the value given.
+        """
+        return Path(path)
+
+    def watch_path(self) -> None:
+        """Watch for changes to the `path` of the directory tree.
+
+        If the path is changed the directory tree will be repopulated using
+        the new value as the root.
+        """
+        self.reload()
+
+    def process_label(self, label: TextType) -> Text:
         """Process a str or Text into a label. Maybe overridden in a subclass to modify how labels are rendered.
 
         Args:
@@ -118,7 +157,19 @@ class DirectoryTree(Tree[DirEntry]):
         first_line = text_label.split()[0]
         return first_line
 
-    def render_label(self, node: TreeNode[DirEntry], base_style: Style, style: Style):
+    def render_label(
+        self, node: TreeNode[DirEntry], base_style: Style, style: Style
+    ) -> Text:
+        """Render a label for the given node.
+
+        Args:
+            node: A tree node.
+            base_style: The base style of the widget.
+            style: The additional style for the label.
+
+        Returns:
+            A Rich Text object containing the label.
+        """
         node_label = node._label.copy()
         node_label.stylize(style)
 
@@ -165,40 +216,44 @@ class DirectoryTree(Tree[DirEntry]):
         """
         return paths
 
-    def load_directory(self, node: TreeNode[DirEntry]) -> None:
+    def _load_directory(self, node: TreeNode[DirEntry]) -> None:
+        """Load the directory contents for a given node.
+
+        Args:
+            node: The node to load the directory contents for.
+        """
         assert node.data is not None
-        dir_path = Path(node.data.path)
         node.data.loaded = True
         directory = sorted(
-            self.filter_paths(dir_path.iterdir()),
+            self.filter_paths(node.data.path.iterdir()),
             key=lambda path: (not path.is_dir(), path.name.lower()),
         )
         for path in directory:
             node.add(
                 path.name,
-                data=DirEntry(str(path), path.is_dir()),
+                data=DirEntry(path),
                 allow_expand=path.is_dir(),
             )
         node.expand()
 
     def _on_mount(self, _: Mount) -> None:
-        self.load_directory(self.root)
+        self._load_directory(self.root)
 
-    def _on_tree_node_expanded(self, event: Tree.NodeSelected) -> None:
+    def _on_tree_node_expanded(self, event: Tree.NodeExpanded) -> None:
         event.stop()
         dir_entry = event.node.data
         if dir_entry is None:
             return
-        if dir_entry.is_dir:
+        if dir_entry.path.is_dir():
             if not dir_entry.loaded:
-                self.load_directory(event.node)
+                self._load_directory(event.node)
         else:
-            self.post_message(self.FileSelected(dir_entry.path))
+            self.post_message(self.FileSelected(event.node, dir_entry.path))
 
     def _on_tree_node_selected(self, event: Tree.NodeSelected) -> None:
         event.stop()
         dir_entry = event.node.data
         if dir_entry is None:
             return
-        if not dir_entry.is_dir:
+        if not dir_entry.path.is_dir():
-            self.post_message(self.FileSelected(dir_entry.path))
+            self.post_message(self.FileSelected(event.node, dir_entry.path))

tests/snapshot_tests/test_snapshots.py

@@ -294,7 +294,7 @@ def test_programmatic_scrollbar_gutter_change(snap_compare):
 
 
 def test_borders_preview(snap_compare):
-    assert snap_compare(CLI_PREVIEWS_DIR / "borders.py", press=["tab", "tab", "enter"])
+    assert snap_compare(CLI_PREVIEWS_DIR / "borders.py", press=["tab", "enter"])
 
 
 def test_colors_preview(snap_compare):

tests/test_data_table.py

@@ -991,3 +991,28 @@ def test_key_string_lookup():
     assert dictionary[RowKey("foo")] == "bar"
     assert dictionary["hello"] == "world"
     assert dictionary[RowKey("hello")] == "world"
+
+
+async def test_scrolling_cursor_into_view():
+    """Regression test for https://github.com/Textualize/textual/issues/2459"""
+
+    class TableApp(App):
+        CSS = "DataTable { height: 100%; }"
+
+        def compose(self):
+            yield DataTable()
+
+        def on_mount(self) -> None:
+            table = self.query_one(DataTable)
+            table.add_column("n")
+            table.add_rows([(n,) for n in range(300)])
+
+        def key_c(self):
+            self.query_one(DataTable).cursor_coordinate = Coordinate(200, 0)
+
+    app = TableApp()
+
+    async with app.run_test() as pilot:
+        await pilot.press("c")
+        await pilot.pause()
+        assert app.query_one(DataTable).scroll_y > 100