fix issue with auto height

CHANGELOG.md

@@ -5,6 +5,16 @@ All notable changes to this project will be documented in this file.
 The format is based on [Keep a Changelog](http://keepachangelog.com/)
 and this project adheres to [Semantic Versioning](http://semver.org/).
 
+## [0.63.5]
+
+### Fixed
+
+- Fixed data table disappearing from tabs https://github.com/Textualize/textual/pull/4567
+
+### Added
+
+- Added `Styles.is_auto_width` and `Style.is_auto_height`
+
 ## [0.63.4]
 
 ### Added
@@ -2023,6 +2033,7 @@ 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
 
+[0.63.5]: https://github.com/Textualize/textual/compare/v0.63.4...v0.63.5
 [0.63.4]: https://github.com/Textualize/textual/compare/v0.63.3...v0.63.4
 [0.63.3]: https://github.com/Textualize/textual/compare/v0.63.2...v0.63.3
 [0.63.2]: https://github.com/Textualize/textual/compare/v0.63.1...v0.63.2

pyproject.toml

@@ -1,6 +1,6 @@
 [tool.poetry]
 name = "textual"
-version = "0.63.4"
+version = "0.63.5"
 homepage = "https://github.com/Textualize/textual"
 repository = "https://github.com/Textualize/textual"
 documentation = "https://textual.textualize.io/"

src/textual/css/styles.py

@@ -441,6 +441,18 @@ def is_relative_height(self) -> bool:
         height = self.height
         return height is not None and height.unit in (Unit.FRACTION, Unit.PERCENT)
 
+    @property
+    def is_auto_width(self) -> bool:
+        """Does the node have automatic width?"""
+        width = self.width
+        return width is not None and width.unit == Unit.AUTO
+
+    @property
+    def is_auto_height(self) -> bool:
+        """Does the node have automatic height?"""
+        height = self.height
+        return height is not None and height.unit == Unit.AUTO
+
     @abstractmethod
     def has_rule(self, rule: str) -> bool:
         """Check if a rule is set on this Styles object.

src/textual/screen.py

@@ -136,7 +136,7 @@ class Screen(Generic[ScreenResultType], Widget):
     Screen {
         layout: vertical;
         overflow-y: auto;
-        background: $surface;
+        background: $surface;        
         
         &:inline {
             height: auto;

src/textual/widget.py

@@ -1211,13 +1211,19 @@ def _get_box_model(
                 min_width -= gutter.width
             content_width = max(content_width, min_width, Fraction(0))
 
-        if styles.max_width is not None:
+        if styles.max_width is not None and not (
+            container.width == 0
+            and not styles.max_width.is_cells
+            and self._parent is not None
+            and self._parent.styles.is_auto_width
+        ):
             # Restrict to maximum width, if set
             max_width = styles.max_width.resolve(
                 container - margin.totals, viewport, width_fraction
             )
             if is_border_box:
                 max_width -= gutter.width
+
             content_width = min(content_width, max_width)
 
         content_width = max(Fraction(0), content_width)
@@ -1255,7 +1261,12 @@ def _get_box_model(
                 min_height -= gutter.height
             content_height = max(content_height, min_height, Fraction(0))
 
-        if styles.max_height is not None:
+        if styles.max_height is not None and not (
+            container.height == 0
+            and not styles.max_height.is_cells
+            and self._parent is not None
+            and self._parent.styles.is_auto_height
+        ):
             # Restrict maximum height, if set
             max_height = styles.max_height.resolve(
                 container - margin.totals, viewport, height_fraction

tests/snapshot_tests/snapshot_apps/data_table_tabs.py

@@ -0,0 +1,35 @@
+from textual.app import App, ComposeResult
+from textual.binding import Binding
+from textual.widgets import TabbedContent, DataTable
+
+
+class Dashboard(App):
+    """Dashboard"""
+
+    BINDINGS = [
+        ("d", "toggle_dark", "Toggle dark mode"),
+        Binding("ctrl+q", "app.quit", "Quit", show=True),
+    ]
+    TITLE = "Dashboard"
+    CSS = """
+
+    DataTable {
+        height: auto;
+    }
+    """
+
+    def compose(self) -> ComposeResult:
+        """Create child widgets for the app."""
+        with TabbedContent("Workflows"):
+            yield DataTable(id="table")
+
+    def on_mount(self) -> None:
+        table = self.query_one(DataTable)
+        table.add_columns("Id", "Description", "Status", "Result Id")
+        for row in [(1, 2, 3, 4), ("a", "b", "c", "d"), ("fee", "fy", "fo", "fum")]:
+            table.add_row(key=row[0], *row)
+
+
+if __name__ == "__main__":
+    app = Dashboard()
+    app.run()

tests/snapshot_tests/test_snapshots.py

@@ -1269,3 +1269,7 @@ def test_grid_gutter(snap_compare):
 def test_multi_keys(snap_compare):
     # https://github.com/Textualize/textual/issues/4542
     assert snap_compare(SNAPSHOT_APPS_DIR / "multi_keys.py")
+
+
+def test_data_table_in_tabs(snap_compare):
+    assert snap_compare(SNAPSHOT_APPS_DIR / "data_table_tabs.py")