Merge pull request #4837 from Textualize/micro-op

micro optimizations

Author: willmcgugan

src/textual/_compositor.py

@@ -593,8 +593,8 @@ def add_widget(
             if not widget._is_mounted:
                 return
             styles = widget.styles
-            visibility = styles.get_rule("visibility")
-            if visibility is not None:
+
+            if (visibility := styles.get_rule("visibility")) is not None:
                 visible = visibility == "visible"
 
             if visible:

src/textual/css/_style_properties.py

@@ -99,7 +99,7 @@ def __set_name__(self, owner: StylesBase, name: str) -> None:
     def __get__(
         self, obj: StylesBase, objtype: type[StylesBase] | None = None
     ) -> PropertyGetType:
-        return cast(PropertyGetType, obj.get_rule(self.name, self.default))
+        return obj.get_rule(self.name, self.default)  # type: ignore[return-value]
 
     def __set__(self, obj: StylesBase, value: PropertySetType | None) -> None:
         _rich_traceback_omit = True
@@ -156,7 +156,7 @@ def __get__(
         Returns:
             The Scalar object or ``None`` if it's not set.
         """
-        return cast("Scalar | None", obj.get_rule(self.name))
+        return obj.get_rule(self.name)  # type: ignore[return-value]
 
     def __set__(
         self, obj: StylesBase, value: float | int | Scalar | str | None
@@ -236,7 +236,7 @@ def __set_name__(self, owner: StylesBase, name: str) -> None:
     def __get__(
         self, obj: StylesBase, objtype: type[StylesBase] | None = None
     ) -> tuple[Scalar, ...] | None:
-        return cast("tuple[Scalar, ...]", obj.get_rule(self.name))
+        return obj.get_rule(self.name)  # type: ignore[return-value]
 
     def __set__(
         self, obj: StylesBase, value: str | Iterable[str | float] | None
@@ -292,10 +292,7 @@ def __get__(
             A ``tuple[EdgeType, Style]`` containing the string type of the box and
                 it's style. Example types are "rounded", "solid", and "dashed".
         """
-        return cast(
-            "tuple[EdgeType, Color]",
-            obj.get_rule(self.name) or ("", self._default_color),
-        )
+        return obj.get_rule(self.name) or ("", self._default_color)  # type: ignore[return-value]
 
     def __set__(self, obj: StylesBase, border: tuple[EdgeType, str | Color] | None):
         """Set the box property.
@@ -506,10 +503,7 @@ class KeylineProperty:
     def __get__(
         self, obj: StylesBase, objtype: type[StylesBase] | None = None
     ) -> tuple[CanvasLineType, Color]:
-        return cast(
-            "tuple[CanvasLineType, Color]",
-            obj.get_rule("keyline", ("none", Color.parse("transparent"))),
-        )
+        return obj.get_rule("keyline", ("none", TRANSPARENT))  # type: ignore[return-value]
 
     def __set__(self, obj: StylesBase, keyline: tuple[str, Color] | None):
         if keyline is None:
@@ -538,7 +532,7 @@ def __get__(
         Returns:
             The Spacing. If unset, returns the null spacing ``(0, 0, 0, 0)``.
         """
-        return cast(Spacing, obj.get_rule(self.name, NULL_SPACING))
+        return obj.get_rule(self.name, NULL_SPACING)  # type: ignore[return-value]
 
     def __set__(self, obj: StylesBase, spacing: SpacingDimensions | None):
         """Set the Spacing.
@@ -591,7 +585,7 @@ def __get__(
         Returns:
             The dock name as a string, or "" if the rule is not set.
         """
-        return cast(DockEdge, obj.get_rule("dock", ""))
+        return obj.get_rule("dock", "")  # type: ignore[return-value]
 
     def __set__(self, obj: StylesBase, dock_name: str | None):
         """Set the Dock property.
@@ -621,7 +615,7 @@ def __get__(
         Returns:
             The ``Layout`` object.
         """
-        return cast("Layout | None", obj.get_rule(self.name))
+        return obj.get_rule(self.name)  # type: ignore[return-value]
 
     def __set__(self, obj: StylesBase, layout: str | Layout | None):
         """
@@ -675,7 +669,7 @@ def __get__(
             The ``ScalarOffset`` indicating the adjustment that
                 will be made to widget position prior to it being rendered.
         """
-        return cast("ScalarOffset", obj.get_rule(self.name, NULL_SCALAR))
+        return obj.get_rule(self.name, NULL_SCALAR)  # type: ignore[return-value]
 
     def __set__(
         self, obj: StylesBase, offset: tuple[int | str, int | str] | ScalarOffset | None
@@ -832,7 +826,7 @@ def __get__(self, obj: StylesBase, objtype: type[StylesBase] | None) -> str:
         Returns:
             The name.
         """
-        return cast(str, obj.get_rule(self.name, ""))
+        return obj.get_rule(self.name, "")  # type: ignore[return-value]
 
     def __set__(self, obj: StylesBase, name: str | None):
         """Set the name property.
@@ -862,7 +856,7 @@ def __set_name__(self, owner: StylesBase, name: str) -> None:
     def __get__(
         self, obj: StylesBase, objtype: type[StylesBase] | None = None
     ) -> tuple[str, ...]:
-        return cast("tuple[str, ...]", obj.get_rule(self.name, ()))
+        return obj.get_rule(self.name, ())  # type: ignore[return-value]
 
     def __set__(self, obj: StylesBase, names: str | tuple[str] | None = None):
         _rich_traceback_omit = True
@@ -900,7 +894,7 @@ def __get__(
         Returns:
             The Color.
         """
-        return cast(Color, obj.get_rule(self.name, self._default_color))
+        return obj.get_rule(self.name, self._default_color)  # type: ignore[return-value]
 
     def __set__(self, obj: StylesBase, color: Color | str | None) -> None:
         """Set the Color.
@@ -987,7 +981,7 @@ def __get__(
         Returns:
             The ``Style`` object.
         """
-        return cast(Style, obj.get_rule(self.name, Style.null()))
+        return obj.get_rule(self.name, Style.null())  # type: ignore[return-value]
 
     def __set__(self, obj: StylesBase, style_flags: Style | str | None) -> None:
         """Set the style using a style flag string.
@@ -1050,7 +1044,7 @@ def __get__(
                 e.g. ``{"offset": Transition(...), ...}``. If no transitions have been set, an empty ``dict``
                 is returned.
         """
-        return cast("dict[str, Transition]", obj.get_rule("transitions", {}))
+        return obj.get_rule("transitions", {})  # type: ignore[return-value]
 
     def __set__(
         self, obj: StylesBase, transitions: dict[str, Transition] | None
@@ -1090,7 +1084,7 @@ def __get__(self, obj: StylesBase, type: type[StylesBase]) -> float:
         Returns:
             The value of the property (in the range (0, 1)).
         """
-        return cast(float, obj.get_rule(self.name, self.default))
+        return obj.get_rule(self.name, self.default)  # type: ignore[return-value]
 
     def __set__(self, obj: StylesBase, value: float | str | None) -> None:
         """Set the property value, clamping it between 0 and 1.
@@ -1146,7 +1140,7 @@ class HatchProperty:
     """Property to expose hatch style."""
 
     def __get__(self, obj: StylesBase, type: type[StylesBase]) -> tuple[str, Color]:
-        return cast("tuple[str, Color]", obj.get_rule("hatch", (" ", TRANSPARENT)))
+        return obj.get_rule("hatch", (" ", TRANSPARENT))  # type: ignore[return-value]
 
     def __set__(self, obj: StylesBase, value: tuple[str, Color | str] | None) -> None:
         _rich_traceback_omit = True

src/textual/css/scalar.py

@@ -50,6 +50,7 @@ class Unit(Enum):
 SYMBOL_UNIT = {v: k for k, v in UNIT_SYMBOL.items()}
 
 _MATCH_SCALAR = re.compile(r"^(-?\d+\.?\d*)(fr|%|w|h|vw|vh)?$").match
+_FRACTION_ONE = Fraction(1)
 
 
 def _resolve_cells(
@@ -284,7 +285,7 @@ def resolve(
             unit = percent_unit
         try:
             dimension = RESOLVE_MAP[unit](
-                value, size, viewport, fraction_unit or Fraction(1)
+                value, size, viewport, fraction_unit or _FRACTION_ONE
             )
         except KeyError:
             raise ScalarResolveError(f"expected dimensions; found {str(self)!r}")

src/textual/css/styles.py

@@ -1,10 +1,9 @@
 from __future__ import annotations
 
-from abc import ABC, abstractmethod
 from dataclasses import dataclass, field
 from functools import lru_cache, partial
 from operator import attrgetter
-from typing import TYPE_CHECKING, Any, Iterable, NamedTuple, cast
+from typing import TYPE_CHECKING, Any, Callable, Iterable, NamedTuple, cast
 
 import rich.repr
 from rich.style import Style
@@ -204,7 +203,7 @@ class DockGroup(NamedTuple):
     z: int
 
 
-class StylesBase(ABC):
+class StylesBase:
     """A common base class for Styles and RenderStyles"""
 
     ANIMATABLE = {
@@ -458,7 +457,6 @@ def is_auto_height(self) -> bool:
         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.
 
@@ -468,8 +466,8 @@ def has_rule(self, rule: str) -> bool:
         Returns:
             ``True`` if the rules is present, otherwise ``False``.
         """
+        raise NotImplementedError()
 
-    @abstractmethod
     def clear_rule(self, rule: str) -> bool:
         """Removes the rule from the Styles object, as if it had never been set.
 
@@ -479,16 +477,16 @@ def clear_rule(self, rule: str) -> bool:
         Returns:
             ``True`` if a rule was cleared, or ``False`` if the rule is already not set.
         """
+        raise NotImplementedError()
 
-    @abstractmethod
     def get_rules(self) -> RulesMap:
         """Get the rules in a mapping.
 
         Returns:
             A TypedDict of the rules.
         """
+        raise NotImplementedError()
 
-    @abstractmethod
     def set_rule(self, rule: str, value: object | None) -> bool:
         """Set a rule.
 
@@ -499,8 +497,8 @@ def set_rule(self, rule: str, value: object | None) -> bool:
         Returns:
             ``True`` if the rule changed, otherwise ``False``.
         """
+        raise NotImplementedError()
 
-    @abstractmethod
     def get_rule(self, rule: str, default: object = None) -> object:
         """Get an individual rule.
 
@@ -511,8 +509,8 @@ def get_rule(self, rule: str, default: object = None) -> object:
         Returns:
             Rule value or default.
         """
+        raise NotImplementedError()
 
-    @abstractmethod
     def refresh(
         self, *, layout: bool = False, children: bool = False, parent: bool = False
     ) -> None:
@@ -524,19 +522,16 @@ def refresh(
             parent: Also refresh the parent.
         """
 
-    @abstractmethod
     def reset(self) -> None:
         """Reset the rules to initial state."""
 
-    @abstractmethod
     def merge(self, other: StylesBase) -> None:
         """Merge values from another Styles.
 
         Args:
             other: A Styles object.
         """
 
-    @abstractmethod
     def merge_rules(self, rules: RulesMap) -> None:
         """Merge rules in to Styles.
 
@@ -686,6 +681,10 @@ class Styles(StylesBase):
 
     important: set[str] = field(default_factory=set)
 
+    def __post_init__(self) -> None:
+        self.get_rule: Callable[[str, object], object] = self._rules.get  # type: ignore[assignment]
+        self.has_rule: Callable[[str], bool] = self._rules.__contains__  # type: ignore[assignment]
+
     def copy(self) -> Styles:
         """Get a copy of this Styles object."""
         return Styles(
@@ -694,10 +693,6 @@ def copy(self) -> Styles:
             important=self.important,
         )
 
-    def has_rule(self, rule: str) -> bool:
-        assert rule in RULE_NAMES_SET, f"no such rule {rule!r}"
-        return rule in self._rules
-
     def clear_rule(self, rule: str) -> bool:
         """Removes the rule from the Styles object, as if it had never been set.
 
@@ -737,9 +732,6 @@ def set_rule(self, rule: str, value: object | None) -> bool:
             self._updates += 1
         return changed
 
-    def get_rule(self, rule: str, default: object = None) -> object:
-        return self._rules.get(rule, default)
-
     def refresh(
         self, *, layout: bool = False, children: bool = False, parent: bool = False
     ) -> None:

src/textual/dom.py

@@ -994,16 +994,17 @@ def rich_style(self) -> Style:
 
         for node in reversed(self.ancestors_with_self):
             styles = node.styles
+            has_rule = styles.has_rule
             opacity *= styles.opacity
-            if styles.has_rule("background"):
+            if has_rule("background"):
                 text_background = background + styles.background
                 background += styles.background.multiply_alpha(opacity)
             else:
                 text_background = background
-            if styles.has_rule("color"):
+            if has_rule("color"):
                 color = styles.color
             style += styles.text_style
-            if styles.has_rule("auto_color") and styles.auto_color:
+            if has_rule("auto_color") and styles.auto_color:
                 color = text_background.get_contrast_text(color.a)
 
         style += Style.from_color(