Underline bar renderable

src/textual/renderables/tab_underline.py

@@ -1,95 +0,0 @@
-from __future__ import annotations
-
-import random
-
-from rich.color import Color, ANSI_COLOR_NAMES
-from rich.console import ConsoleOptions, Console, RenderResult
-from rich.segment import Segment
-from rich.style import Style
-
-
-class UnderlineBar:
-    def __init__(
-        self,
-        highlight_range: tuple[float, float] = 0,
-        range_color: Color = Color.parse("yellow"),
-        other_color: Color = Color.parse("default"),
-        background_color: Color = Color.parse("default"),
-        width: int | None = None,
-    ) -> None:
-        self.highlight_range = highlight_range
-        self.highlight_style = Style.from_color(
-            color=range_color, bgcolor=background_color
-        )
-        self.other_style = Style.from_color(color=other_color, bgcolor=background_color)
-        self.width = width
-
-    def __rich_console__(
-        self, console: Console, options: ConsoleOptions
-    ) -> RenderResult:
-        half_bar_right = "╸"
-        half_bar_left = "╺"
-        bar = "━"
-        width = (self.width or options.max_width) - 1
-        start, end = self.highlight_range
-
-        # Round start and end to nearest half
-        start = round(start * 2) / 2
-        end = round(end * 2) / 2
-
-        half_start = start - int(start) > 0
-        half_end = end - int(end) > 0
-
-        # Initial non-highlighted portion of bar
-        yield Segment(bar * (int(start - 0.5)), style=self.other_style)
-        if not half_start and start > 0:
-            yield Segment(half_bar_right, style=self.other_style)
-
-        # If we have a half bar at start and end, we need 1 less full bar
-        full_bar_width = int(end) - int(start)
-        if half_start and half_end:
-            full_bar_width -= 1
-
-        # The highlighted portion
-        if not half_start:
-            yield Segment(bar * full_bar_width, style=self.highlight_style)
-        else:
-            yield Segment(half_bar_left, style=self.highlight_style)
-            yield Segment(bar * full_bar_width, style=self.highlight_style)
-        if half_end:
-            yield Segment(half_bar_right, style=self.highlight_style)
-
-        # The non-highlighted tail
-        if not half_end and end - width != 1:
-            yield Segment(half_bar_left, style=self.other_style)
-        yield Segment(bar * (int(width) - int(end)), style=self.other_style)
-
-
-if __name__ == "__main__":
-    console = Console()
-
-    def frange(start, end, step):
-        current = start
-        while current < end:
-            yield current
-            current += step
-
-        while current >= 0:
-            yield current
-            current -= step
-
-    start_range = frange(0, 12, 0.5)
-    end_range = frange(6, 18, 0.5)
-    ranges = zip(start_range, end_range)
-
-    for range in ranges:
-        color = random.choice(list(ANSI_COLOR_NAMES.keys()))
-        console.print(
-            UnderlineBar(
-                range,
-                range_color=Color.parse(color),
-                other_color=Color.parse("#4f4f4f"),
-                width=18,
-            )
-        )
-        console.print()

src/textual/renderables/underline_bar.py

@@ -0,0 +1,112 @@
+from __future__ import annotations
+
+import random
+
+from rich.color import Color, ANSI_COLOR_NAMES
+from rich.console import ConsoleOptions, Console, RenderResult
+from rich.segment import Segment
+from rich.style import Style
+
+
+class UnderlineBar:
+    """Thin horizontal bar with a portion highlighted.
+
+    Args:
+        highlight_range (tuple[float, float]): The range to highlight. Defaults to ``(0, 0)`` (no highlight)
+        highlight_color (Color | str): The color of the highlighted range of the bar.
+        non_highlight_color (Color | str): The color of the non-highlighted range(s) of the bar.
+        background_color (Color | str): The background color of the entire bar.
+        width (int, optional): The width of the bar, or ``None`` to fill available width.
+    """
+
+    def __init__(
+        self,
+        highlight_range: tuple[float, float] = (0, 0),
+        highlight_color: Color | str = "magenta",
+        non_highlight_color: Color | str = "grey37",
+        background_color: Color | str = "default",
+        width: int | None = None,
+    ) -> None:
+        self.highlight_range = highlight_range
+        self.highlight_style = Style(color=highlight_color, bgcolor=background_color)
+        self.non_highlight_style = Style(
+            color=non_highlight_color, bgcolor=background_color
+        )
+        self.width = width
+
+    def __rich_console__(
+        self, console: Console, options: ConsoleOptions
+    ) -> RenderResult:
+        half_bar_right = "╸"
+        half_bar_left = "╺"
+        bar = "━"
+        width = self.width or options.max_width
+        start, end = self.highlight_range
+
+        start = max(start, 0)
+        end = min(end, width)
+
+        if start == end == 0:
+            yield Segment(bar * width, style=self.non_highlight_style)
+            return
+
+        # Round start and end to nearest half
+        start = round(start * 2) / 2
+        end = round(end * 2) / 2
+
+        # Check if we start/end on a number that rounds to a .5
+        half_start = start - int(start) > 0
+        half_end = end - int(end) > 0
+
+        # Initial non-highlighted portion of bar
+        yield Segment(bar * (int(start - 0.5)), style=self.non_highlight_style)
+        if not half_start and start > 0:
+            yield Segment(half_bar_right, style=self.non_highlight_style)
+
+        # The highlighted portion
+        bar_width = int(end) - int(start)
+        if half_start:
+            yield Segment(
+                half_bar_left + bar * (bar_width - 1), style=self.highlight_style
+            )
+        else:
+            yield Segment(bar * bar_width, style=self.highlight_style)
+        if half_end:
+            yield Segment(half_bar_right, style=self.highlight_style)
+
+        # The non-highlighted tail
+        if not half_end and end - width != 0:
+            yield Segment(half_bar_left, style=self.non_highlight_style)
+        yield Segment(bar * (int(width) - int(end) - 1), style=self.non_highlight_style)
+
+
+if __name__ == "__main__":
+    console = Console()
+
+    def frange(start, end, step):
+        current = start
+        while current < end:
+            yield current
+            current += step
+
+        while current >= 0:
+            yield current
+            current -= step
+
+    step = 0.5
+    start_range = frange(0.5, 10.5, step)
+    end_range = frange(10, 20, step)
+    ranges = zip(start_range, end_range)
+
+    console.print(UnderlineBar(width=20), f"   (.0, .0)")
+
+    for range in ranges:
+        color = random.choice(list(ANSI_COLOR_NAMES.keys()))
+        console.print(
+            UnderlineBar(
+                range,
+                highlight_color=Color.parse(color),
+                width=20,
+            ),
+            f"   {range}",
+        )

tests/renderables/test_underline_bar.py

@@ -0,0 +1,98 @@
+from tests.utilities.render import render
+from textual.renderables.underline_bar import UnderlineBar
+
+MAGENTA = "\x1b[35;49m"
+GREY = "\x1b[38;5;59;49m"
+STOP = "\x1b[0m"
+
+
+def test_no_highlight():
+    bar = UnderlineBar(width=6)
+    assert render(bar) == f"{GREY}━━━━━━{STOP}"
+
+
+def test_highlight_from_zero():
+    bar = UnderlineBar(highlight_range=(0, 2.5), width=6)
+    assert render(bar) == (
+        f"{MAGENTA}━━{STOP}{MAGENTA}╸{STOP}{GREY}━━━{STOP}"
+    )
+
+
+def test_highlight_from_zero_point_five():
+    bar = UnderlineBar(highlight_range=(0.5, 2), width=6)
+    assert render(bar) == (
+        f"{MAGENTA}╺━{STOP}{GREY}╺{STOP}{GREY}━━━{STOP}"
+    )
+
+
+def test_highlight_middle():
+    bar = UnderlineBar(highlight_range=(2, 4), width=6)
+    assert render(bar) == (
+        f"{GREY}━{STOP}"
+        f"{GREY}╸{STOP}"
+        f"{MAGENTA}━━{STOP}"
+        f"{GREY}╺{STOP}"
+        f"{GREY}━{STOP}"
+    )
+
+
+def test_highlight_half_start():
+    bar = UnderlineBar(highlight_range=(2.5, 4), width=6)
+    assert render(bar) == (
+        f"{GREY}━━{STOP}"
+        f"{MAGENTA}╺━{STOP}"
+        f"{GREY}╺{STOP}"
+        f"{GREY}━{STOP}"
+    )
+
+
+def test_highlight_half_end():
+    bar = UnderlineBar(highlight_range=(2, 4.5), width=6)
+    assert render(bar) == (
+        f"{GREY}━{STOP}"
+        f"{GREY}╸{STOP}"
+        f"{MAGENTA}━━{STOP}"
+        f"{MAGENTA}╸{STOP}"
+        f"{GREY}━{STOP}"
+    )
+
+
+def test_highlight_half_start_and_half_end():
+    bar = UnderlineBar(highlight_range=(2.5, 4.5), width=6)
+    assert render(bar) == (
+        f"{GREY}━━{STOP}"
+        f"{MAGENTA}╺━{STOP}"
+        f"{MAGENTA}╸{STOP}"
+        f"{GREY}━{STOP}"
+    )
+
+
+def test_highlight_to_near_end():
+    bar = UnderlineBar(highlight_range=(3, 5.5), width=6)
+    assert render(bar) == (
+        f"{GREY}━━{STOP}"
+        f"{GREY}╸{STOP}"
+        f"{MAGENTA}━━{STOP}"
+        f"{MAGENTA}╸{STOP}"
+    )
+
+
+def test_highlight_to_end():
+    bar = UnderlineBar(highlight_range=(3, 6), width=6)
+    assert render(bar) == (
+        f"{GREY}━━{STOP}{GREY}╸{STOP}{MAGENTA}━━━{STOP}"
+    )
+
+
+def test_highlight_out_of_bounds_start():
+    bar = UnderlineBar(highlight_range=(-2, 3), width=6)
+    assert render(bar) == (
+        f"{MAGENTA}━━━{STOP}{GREY}╺{STOP}{GREY}━━{STOP}"
+    )
+
+
+def test_highlight_out_of_bounds_end():
+    bar = UnderlineBar(highlight_range=(3, 9), width=6)
+    assert render(bar) == (
+        f"{GREY}━━{STOP}{GREY}╸{STOP}{MAGENTA}━━━{STOP}"
+    )

tests/utilities/render.py

@@ -0,0 +1,24 @@
+import io
+import re
+
+from rich.console import Console, RenderableType
+
+
+re_link_ids = re.compile(r"id=[\d\.\-]*?;.*?\x1b")
+
+
+def replace_link_ids(render: str) -> str:
+    """Link IDs have a random ID and system path which is a problem for
+    reproducible tests.
+
+    """
+    return re_link_ids.sub("id=0;foo\x1b", render)
+
+
+def render(renderable: RenderableType, no_wrap: bool = False) -> str:
+    console = Console(
+        width=100, file=io.StringIO(), color_system="truecolor", legacy_windows=False
+    )
+    console.print(renderable, no_wrap=no_wrap)
+    output = replace_link_ids(console.file.getvalue())
+    return output