Increase URL parsing speed by approximately 2 times

src/httpx2/CHANGELOG.md

@@ -11,6 +11,10 @@ The format is based on [Keep a Changelog](https://keepachangelog.com/en/1.0.0/).
 * Add the public `Origin` value object and `URL.origin` property for normalized,
   hashable origin comparisons. ([#1134](https://github.com/pydantic/httpx2/pull/1134))
 
+### Changed
+
+* Improve URL parsing performance by approximately 2x. ([#1139](https://github.com/pydantic/httpx2/pull/1139))
+
 ## 2.10.0 (August 9th, 2026)
 
 ### Added

src/httpx2/httpx2/_urlparse.py

@@ -34,6 +34,10 @@
 
 PERCENT_ENCODED_REGEX = re.compile("%[A-Fa-f0-9]{2}")
 
+# These are the ASCII characters that are not printable: the C0 control
+# characters and DEL. One regex search is faster than a test of each character.
+NON_PRINTABLE_ASCII_REGEX = re.compile("[\x00-\x1f\x7f]")
+
 # https://url.spec.whatwg.org/#percent-encoded-bytes
 
 # The fragment percent-encode set is the C0 control percent-encode set
@@ -208,9 +212,9 @@ def urlparse(url: str = "", **kwargs: str | None) -> ParseResult:
 
     # If a URL includes any ASCII control characters including \t, \r, \n,
     # then treat it as invalid.
-    if any(char.isascii() and not char.isprintable() for char in url):
-        char = next(char for char in url if char.isascii() and not char.isprintable())
-        idx = url.find(char)
+    if (match := NON_PRINTABLE_ASCII_REGEX.search(url)) is not None:
+        char = match.group()
+        idx = match.start()
         error = f"Invalid non-printable ASCII character in URL, {char!r} at position {idx}."
         raise InvalidURL(error)
 
@@ -256,9 +260,9 @@ def urlparse(url: str = "", **kwargs: str | None) -> ParseResult:
 
             # If a component includes any ASCII control characters including \t, \r, \n,
             # then treat it as invalid.
-            if any(char.isascii() and not char.isprintable() for char in value):
-                char = next(char for char in value if char.isascii() and not char.isprintable())
-                idx = value.find(char)
+            if (match := NON_PRINTABLE_ASCII_REGEX.search(value)) is not None:
+                char = match.group()
+                idx = match.start()
                 error = f"Invalid non-printable ASCII character in URL {key} component, {char!r} at position {idx}."
                 raise InvalidURL(error)
 
@@ -480,9 +484,13 @@ def quote(string: str, safe: str) -> str:
         need to be escaped. Unreserved characters are always treated as safe.
         See: https://www.rfc-editor.org/rfc/rfc3986#section-2.3
     """
+    # Fast path for strings that contain no '%xx' escape sequence.
+    if "%" not in string:
+        return percent_encoded(string, safe=safe)
+
     parts: list[str] = []
     current_position = 0
-    for match in re.finditer(PERCENT_ENCODED_REGEX, string):
+    for match in PERCENT_ENCODED_REGEX.finditer(string):
         start_position, end_position = match.start(), match.end()
         matched_text = match.group(0)
         # Add any text up to the '%xx' escape sequence.

tests/httpx2/models/test_url.py

@@ -452,6 +452,52 @@ def test_url_non_printing_character_in_component() -> None:
     assert str(exc.value) == ("Invalid non-printable ASCII character in URL path component, '\\n' at position 1.")
 
 
+# The limits of the control character ranges (0x00, 0x1f, 0x7f), and CR, which
+# a URL must not contain.
+CONTROL_CHARACTERS = [0x00, 0x0D, 0x1F, 0x7F]
+
+
+@pytest.mark.parametrize("code", CONTROL_CHARACTERS)
+def test_url_ascii_control_character_in_url(code: int) -> None:
+    char = chr(code)
+    with pytest.raises(httpx2.InvalidURL) as exc:
+        httpx2.URL("https://www.example.com/" + char)
+    assert str(exc.value) == (f"Invalid non-printable ASCII character in URL, {char!r} at position 24.")
+
+
+@pytest.mark.parametrize("code", CONTROL_CHARACTERS)
+def test_url_ascii_control_character_in_component(code: int) -> None:
+    char = chr(code)
+    with pytest.raises(httpx2.InvalidURL) as exc:
+        httpx2.URL("https://www.example.com", path="/" + char)
+    assert str(exc.value) == (f"Invalid non-printable ASCII character in URL path component, {char!r} at position 1.")
+
+
+@pytest.mark.parametrize(("code", "expected"), [(0x20, "%20"), (0x7E, "~")])
+def test_url_printable_ascii_next_to_control_range_is_allowed(code: int, expected: str) -> None:
+    # Space (0x20) and '~' (0x7e) are adjacent to the control character ranges.
+    # The parser must not reject them.
+    char = chr(code)
+    assert char.isprintable()
+    assert str(httpx2.URL("https://www.example.com/" + char)) == "https://www.example.com/" + expected
+
+
+@pytest.mark.parametrize("code", [0x85, 0xA0, 0x200B])
+def test_url_non_printing_character_outside_ascii_is_allowed(code: int) -> None:
+    # These characters are not printable, but they are also not ASCII.
+    # The parser applies percent-encoding to them and does not reject them.
+    char = chr(code)
+    assert not char.isprintable() and not char.isascii()
+    percent_encoded = "".join(f"%{byte:02X}" for byte in char.encode("utf-8"))
+    assert str(httpx2.URL("https://www.example.com/" + char)) == "https://www.example.com/" + percent_encoded
+
+
+def test_url_reports_first_control_character_position() -> None:
+    with pytest.raises(httpx2.InvalidURL) as exc:
+        httpx2.URL("https://www.example.com/a\tb\nc")
+    assert str(exc.value) == ("Invalid non-printable ASCII character in URL, '\\t' at position 25.")
+
+
 # Test for url components
 
 

tests/test_benchmark.py

@@ -16,6 +16,11 @@
 
 TYPICAL_URL = "https://www.example.org:8443/path/to/resource?key=value&other=1#frag"
 
+# The cost to parse a URL increases with its length. These constants give a long
+# URL and a URL that contains '%xx' escape sequences.
+LONG_QUERY_URL = "https://www.example.org/search?" + "&".join(f"field{i}=value{i}" for i in range(60))
+PERCENT_ENCODED_URL = "https://www.example.org/path%2Fto%2Fresource?key=a%20value&other=%C3%A9"
+
 HEADERS: list[tuple[str, str]] = [
     ("host", "example.org"),
     ("user-agent", "httpx2-bench/1.0"),
@@ -53,6 +58,14 @@ def test_bench_url_parse(benchmark: BenchmarkFixture) -> None:
     benchmark(httpx2.URL, TYPICAL_URL)
 
 
+def test_bench_url_parse_long_query(benchmark: BenchmarkFixture) -> None:
+    benchmark(httpx2.URL, LONG_QUERY_URL)
+
+
+def test_bench_url_parse_percent_encoded(benchmark: BenchmarkFixture) -> None:
+    benchmark(httpx2.URL, PERCENT_ENCODED_URL)
+
+
 def test_bench_url_join(benchmark: BenchmarkFixture) -> None:
     base = httpx2.URL(TYPICAL_URL)
     benchmark(base.join, "/path/to/resource?key=value")