fix(traceback): highlight win32 paths

`PathHighlighter` uses a regex to parse paths for highlighting.
It used `/` as the final path component delimiter. This diff
changes that to "either `/` or `\`".

I toyed with using `os.path.sep`, but there's no reason to *not*
highlight paths from other OSes than the one we're running on
at the moment.

Author: Zoltán Nagy

rich/traceback.py

@@ -246,7 +246,7 @@ class Trace:
 
 
 class PathHighlighter(RegexHighlighter):
-    highlights = [r"(?P<dim>.*/)(?P<bold>.+)"]
+    highlights = [r"(?P<dim>.*(/|\\))(?P<bold>.+)"]
 
 
 class Traceback:

tests/test_traceback.py

@@ -6,8 +6,9 @@
 import pytest
 
 from rich.console import Console
+from rich.text import Span
 from rich.theme import Theme
-from rich.traceback import Traceback, install
+from rich.traceback import install, PathHighlighter, Traceback
 
 
 def test_handler():
@@ -373,3 +374,18 @@ def test_notes() -> None:
         traceback = Traceback()
 
         assert traceback.trace.stacks[0].notes == ["Hello", "World"]
+
+
+def test_path_highlighter() -> None:
+    """Check that PathHighlighter correctly highlights both win32 and *nix paths"""
+    path_highlighter = PathHighlighter()
+
+    assert path_highlighter("/foo/bar/baz").spans == [
+        Span(0, 9, "dim"),
+        Span(9, 12, "bold"),
+    ]
+
+    assert path_highlighter("'\\\\?\\C:\\foo\\bar\\baz").spans == [
+        Span(0, 16, "dim"),
+        Span(16, 19, "bold"),
+    ]