From c332718c313a741856f2106ea2cf60a98934f7c4 Mon Sep 17 00:00:00 2001
From: Troy Zhong <troyz@umich.edu>
Date: Mon, 29 Sep 2025 14:44:41 -0400
Subject: [PATCH] fix(ReprHighlighter): only match standalone hex literals;
 support 0X, sign, underscores; add boundary tests

---
 rich/highlighter.py       |  2 +-
 tests/test_highlighter.py | 36 ++++++++++++++++++++++++++++++++++++
 2 files changed, 37 insertions(+), 1 deletion(-)

diff --git a/rich/highlighter.py b/rich/highlighter.py
index e4c462e2b6..ebd1982b33 100644
--- a/rich/highlighter.py
+++ b/rich/highlighter.py
@@ -95,7 +95,7 @@ class ReprHighlighter(RegexHighlighter):
             r"\b(?P<bool_true>True)\b|\b(?P<bool_false>False)\b|\b(?P<none>None)\b",
             r"(?P<ellipsis>\.\.\.)",
             r"(?P<number_complex>(?<!\w)(?:\-?[0-9]+\.?[0-9]*(?:e[-+]?\d+?)?)(?:[-+](?:[0-9]+\.?[0-9]*(?:e[-+]?\d+)?))?j)",
-            r"(?P<number>(?<!\w)\-?[0-9]+\.?[0-9]*(e[-+]?\d+?)?\b|0x[0-9a-fA-F]*)",
+            r"(?P<number>(?<!\w)\-?[0-9]+\.?[0-9]*(e[-+]?\d+?)?\b|(?<![0-9A-Za-z_])[+-]?0[xX][0-9A-Fa-f](?:_?[0-9A-Fa-f])*(?![0-9A-Za-z_]))",
             r"(?P<path>\B(/[-\w._+]+)*\/)(?P<filename>[-\w._+]*)?",
             r"(?<![\\\w])(?P<str>b?'''.*?(?<!\\)'''|b?'.*?(?<!\\)'|b?\"\"\".*?(?<!\\)\"\"\"|b?\".*?(?<!\\)\")",
             r"(?P<url>(file|https|http|ws|wss)://[-0-9a-zA-Z$_+!`(),.?/;:&=%#~@]*)",
diff --git a/tests/test_highlighter.py b/tests/test_highlighter.py
index d19928274a..2ee97beab1 100644
--- a/tests/test_highlighter.py
+++ b/tests/test_highlighter.py
@@ -1,5 +1,7 @@
 """Tests for the highlighter classes."""
+
 import json
+import re
 from typing import List
 
 import pytest
@@ -12,6 +14,8 @@
 )
 from rich.text import Span, Text
 
+HEX_LITERAL_RE = re.compile(r"[+-]?0x[0-9a-f](?:_?[0-9a-f])*$", re.IGNORECASE)
+
 
 def test_wrong_type():
     highlighter = NullHighlighter()
@@ -167,6 +171,38 @@ def test_highlight_regex(test: str, spans: List[Span]):
     assert text.spans == spans
 
 
+@pytest.mark.parametrize(
+    "literal, should_highlight",
+    [
+        ("0xFF", True),
+        ("0Xff", True),
+        ("-0x1A", True),
+        ("+0x2a", True),
+        ("0xdead_beef", True),
+        ("0xDEAD_BEEF", True),
+        ("(0x2A)", True),
+        (",0x2A", True),
+        ("1920x1080", False),
+        ("abc0x123", False),
+        ("eth0x1", False),
+        ("foo0xFFbar", False),
+        ("0xdead__beef", False),
+        ("0x_deadbeef", False),
+        ("0x123_", False),
+    ],
+)
+def test_hex_boundaries(literal: str, should_highlight: bool) -> None:
+    text = Text(literal)
+    highlighter = ReprHighlighter()
+    highlighter.highlight(text)
+    has_hex_highlight = any(
+        span.style == "repr.number"
+        and HEX_LITERAL_RE.fullmatch(text.plain[span.start : span.end])
+        for span in text.spans
+    )
+    assert has_hex_highlight is should_highlight
+
+
 def test_highlight_json_with_indent():
     json_string = json.dumps({"name": "apple", "count": 1}, indent=4)
     text = Text(json_string)