Change DOM queries to be case-sensitive for classes and IDs

See #1041 and #1047.

Author: davep

CHANGELOG.md

@@ -24,6 +24,7 @@ and this project adheres to [Semantic Versioning](http://semver.org/).
 - Widgets are now closed in reversed DOM order
 - Input widget justify hardcoded to left to prevent text-align interference
 - Changed `textual run` so that it patches `argv` in more situations
+- DOM classes and IDs are now always treated fully case-sensitive https://github.com/Textualize/textual/issues/1047
 
 ### Added
 

src/textual/css/model.py

@@ -44,7 +44,6 @@ class Selector:
     type: SelectorType = SelectorType.TYPE
     pseudo_classes: list[str] = field(default_factory=list)
     specificity: Specificity3 = field(default_factory=lambda: (0, 0, 0))
-    _name_lower: str = field(default="", repr=False)
     advance: int = 1
 
     @property
@@ -61,7 +60,6 @@ def css(self) -> str:
             return f"#{self.name}{pseudo_suffix}"
 
     def __post_init__(self) -> None:
-        self._name_lower = self.name.lower()
         self._checks = {
             SelectorType.UNIVERSAL: self._check_universal,
             SelectorType.TYPE: self._check_type,
@@ -94,21 +92,21 @@ def _check_universal(self, node: DOMNode) -> bool:
         return node.has_pseudo_class(*self.pseudo_classes)
 
     def _check_type(self, node: DOMNode) -> bool:
-        if self._name_lower not in node._css_type_names:
+        if self.name not in node._css_type_names:
             return False
         if self.pseudo_classes and not node.has_pseudo_class(*self.pseudo_classes):
             return False
         return True
 
     def _check_class(self, node: DOMNode) -> bool:
-        if not node.has_class(self._name_lower):
+        if not node.has_class(self.name):
             return False
         if self.pseudo_classes and not node.has_pseudo_class(*self.pseudo_classes):
             return False
         return True
 
     def _check_id(self, node: DOMNode) -> bool:
-        if not node.id == self._name_lower:
+        if not node.id == self.name:
             return False
         if self.pseudo_classes and not node.has_pseudo_class(*self.pseudo_classes):
             return False

src/textual/dom.py

@@ -108,7 +108,7 @@ class DOMNode(MessagePump):
 
     # True if this node inherits the CSS from the base class.
     _inherit_css: ClassVar[bool] = True
-    # List of names of base class (lower cased) that inherit CSS
+    # List of names of base classes that inherit CSS
     _css_type_names: ClassVar[frozenset[str]] = frozenset()
 
     def __init__(
@@ -168,7 +168,7 @@ def __init_subclass__(cls, inherit_css: bool = True) -> None:
         cls._inherit_css = inherit_css
         css_type_names: set[str] = set()
         for base in cls._css_bases(cls):
-            css_type_names.add(base.__name__.lower())
+            css_type_names.add(base.__name__)
         cls._css_type_names = frozenset(css_type_names)
 
     def get_component_styles(self, name: str) -> RenderStyles:

tests/test_query.py

@@ -54,7 +54,9 @@ class App(Widget):
         assert list(app.query("#main")) == [main_view]
         assert list(app.query("View#main")) == [main_view]
         assert list(app.query("#widget1")) == [widget1]
+        assert list(app.query("#Widget1")) == [] # Note case.
         assert list(app.query("#widget2")) == [widget2]
+        assert list(app.query("#Widget2")) == [] # Note case.
 
         assert list(app.query("Widget.float")) == [sidebar, tooltip, helpbar]
         assert list(app.query(Widget).filter(".float")) == [sidebar, tooltip, helpbar]