render selection

src/textual/content.py

@@ -27,6 +27,8 @@
 from textual._loop import loop_last
 from textual.color import Color
 from textual.css.types import TextAlign
+from textual.geometry import Offset
+from textual.selection import Selection
 from textual.strip import Strip
 from textual.visual import Style, Visual
 
@@ -270,7 +272,9 @@ def render_strips(
             ),
             no_wrap=False,
             tab_size=8,
+            selection=widget.selection,
         )
+
         if height is not None:
             lines = lines[:height]
 
@@ -948,13 +952,30 @@ def wrap(
         overflow: OverflowMethod = "fold",
         no_wrap: bool = False,
         tab_size: int = 8,
+        selection: Selection | None = None,
     ) -> list[Content]:
         lines: list[Content] = []
 
+        selection = Selection(Offset(10, 0), Offset(20, 1))
+
+        if selection is not None:
+            get_span = selection.get_span
+        else:
+
+            def get_span(y: int) -> tuple[int, int] | None:
+                return None
+
         for line_no, line in enumerate(self.split(allow_blank=True)):
             if "\t" in line._text:
                 line = line.expand_tabs(tab_size)
             line = line.stylize(Style.from_meta({"offset": (line_no, 0)}))
+
+            if (span := get_span(line_no)) is not None:
+                start, end = span
+                if end == -1:
+                    end = len(line.plain)
+                line = line.stylize(Style(reverse=True), start, end)
+
             if no_wrap:
                 new_lines = [line]
             else:
@@ -964,6 +985,7 @@ def wrap(
             new_lines = _align_lines(new_lines, width, align=align, overflow=overflow)
             new_lines = [line.truncate(width, overflow=overflow) for line in new_lines]
             lines.extend(new_lines)
+
         return lines
 
     def highlight_regex(

src/textual/screen.py

@@ -53,9 +53,10 @@
 from textual.reactive import Reactive, var
 from textual.renderables.background_screen import BackgroundScreen
 from textual.renderables.blank import Blank
+from textual.selection import Selection
 from textual.signal import Signal
 from textual.timer import Timer
-from textual.widget import Selection, Widget
+from textual.widget import Widget
 from textual.widgets import Tooltip
 from textual.widgets._toast import ToastRack
 

src/textual/selection.py

@@ -0,0 +1,49 @@
+from typing import NamedTuple
+
+from textual.geometry import Offset
+
+
+class Selection(NamedTuple):
+    """A selected range of lines."""
+
+    start: Offset | None
+    """Offset or None for `start`."""
+    end: Offset | None
+    """Offset or None for `end`."""
+
+    def get_span(self, y: int) -> tuple[int, int] | None:
+        """Get the selected span in a given line.
+
+        Args:
+            y: Offset of the line.
+
+        Returns:
+            A tuple of x start and end offset, or None for no selection.
+        """
+        start, end = self
+        if start is None and end is None:
+            # Selection covers everything
+            return 0, -1
+
+        if start is not None and end is not None:
+            if y < start.y or y > end.y:
+                # Outside
+                return None
+            if y == start.y == end.y:
+                # Same line
+                return start.x, end.x
+            if y == end.y:
+                # Last line
+                return 0, end.x
+            # Remaining lines
+            return start.x, -1
+
+        if start is None and end is not None:
+            if y == end.y:
+                return 0, end.x
+            return 0, -1
+
+        if end is None and start is not None:
+            if y == start.y:
+                return start.x, -1
+        return 0, -1

src/textual/visual.py

@@ -110,6 +110,7 @@ class Style:
     dim: bool | None = None
     italic: bool | None = None
     underline: bool | None = None
+    reverse: bool | None = None
     strike: bool | None = None
     link: str | None = None
     _meta: bytes | None = None
@@ -122,6 +123,7 @@ def __rich_repr__(self) -> rich.repr.Result:
         yield "dim", self.dim, None
         yield "italic", self.italic, None
         yield "underline", self.underline, None
+        yield "reverse", self.reverse, None
         yield "strike", self.strike, None
         if self._meta is not None:
             yield "meta", self.meta
@@ -137,6 +139,7 @@ def __add__(self, other: object) -> Style:
             self.dim if other.dim is None else other.dim,
             self.italic if other.italic is None else other.italic,
             self.underline if other.underline is None else other.underline,
+            self.reverse if other.reverse is None else other.reverse,
             self.strike if other.strike is None else other.strike,
             self.link if other.link is None else other.link,
             self._meta if other._meta is None else other._meta,
@@ -163,6 +166,7 @@ def from_rich_style(
             dim=rich_style.dim,
             italic=rich_style.italic,
             underline=rich_style.underline,
+            reverse=rich_style.reverse,
             strike=rich_style.strike,
         )
 
@@ -186,6 +190,7 @@ def from_styles(cls, styles: StylesBase) -> Style:
             dim=text_style.italic,
             italic=text_style.italic,
             underline=text_style.underline,
+            reverse=text_style.reverse,
             strike=text_style.strike,
             auto_color=styles.auto_color,
         )
@@ -208,6 +213,7 @@ def rich_style(self) -> RichStyle:
             dim=self.dim,
             italic=self.italic,
             underline=self.underline,
+            reverse=self.reverse,
             strike=self.strike,
             link=self.link,
             meta=self.meta,
@@ -219,6 +225,7 @@ def without_color(self) -> Style:
             bold=self.bold,
             dim=self.dim,
             italic=self.italic,
+            reverse=self.reverse,
             strike=self.strike,
             link=self.link,
             _meta=self._meta,

src/textual/widget.py

@@ -84,6 +84,7 @@
 from textual.reactive import Reactive
 from textual.renderables.blank import Blank
 from textual.rlock import RLock
+from textual.selection import Selection
 from textual.strip import Strip
 from textual.visual import Style as VisualStyle
 from textual.visual import Visual, visualize
@@ -109,29 +110,10 @@
 }
 
 
-_NULL_STYLE = Style()
 _MOUSE_EVENTS_DISALLOW_IF_DISABLED = (events.MouseEvent, events.Enter, events.Leave)
 _MOUSE_EVENTS_ALLOW_IF_DISABLED = (events.MouseScrollDown, events.MouseScrollUp)
 
 
-class Selection(NamedTuple):
-    """A selected range of lines."""
-
-    start: Offset | None
-    end: Offset | None
-
-    def get_selection(self, line_no: int) -> tuple[int, int] | None:
-        start, end = self
-        if start is None and end is None:
-            # Selection covers everything
-            return 0, -1
-        if start is not None and end is not None:
-            if line_no < start.y or line_no >= end.y:
-                return None
-            # TODO
-        return None
-
-
 @rich.repr.auto
 class AwaitMount:
     """An *optional* awaitable returned by [mount][textual.widget.Widget.mount] and [mount_all][textual.widget.Widget.mount_all].
@@ -654,6 +636,10 @@ def _render_widget(self) -> Widget:
         # Will return the "cover widget" if one is set, otherwise self.
         return self._cover_widget if self._cover_widget is not None else self
 
+    @property
+    def selection(self) -> Selection | None:
+        return self.screen.selections.get(self, None)
+
     def _cover(self, widget: Widget) -> None:
         """Set a widget used to replace the visuals of this widget (used for loading indicator).