changes made as per reviews

Author: Davda-James

Lib/test/test_urlparse.py

@@ -1229,10 +1229,10 @@ def test_parse_qs_encoding(self):
 
     def test_qsl_strict_parsing_raises(self):
         with self.assertRaises(ValueError):
-            urllib.parse.parse_qsl("foo", strict_parsing=True)
+            urllib.parse.parse_qsl("foo=^", strict_parsing=True)
 
         with self.assertRaises(ValueError):
-            urllib.parse.parse_qsl(b"foo", strict_parsing=True)
+            urllib.parse.parse_qsl(b"foo=`", strict_parsing=True)
 
     def test_parse_qsl_encoding(self):
         result = urllib.parse.parse_qsl("key=\u0141%E9", encoding="latin-1")

Lib/urllib/parse.py

@@ -91,8 +91,8 @@
 # Unsafe bytes to be removed per WHATWG spec
 _UNSAFE_URL_BYTES_TO_REMOVE = ['\t', '\r', '\n']
 
-# Allowed valid characters in parse_qsl
-_VALID_QUERY_CHARS = "-._~!$&'()*+,;=:@/?%"
+# Allowed valid characters in parse_qsl as per RFC 3986.
+_VALID_RFC3986_QUERY_CHARS = "-._~!$&'()*+,;=:@/?%"
 
 def clear_cache():
     """Clear internal performance caches. Undocumented; some tests want it."""
@@ -781,12 +781,12 @@ def parse_qs(qs, keep_blank_values=False, strict_parsing=False,
             parsed_result[name] = [value]
     return parsed_result
 
-def _is_valid_query(to_check: str) -> bool:
+def _is_valid_rfc3986_query(chars):
     """Return True if all characters are valid per RFC 3986."""
-    for ch in to_check:
+    for ch in chars:
         if not ch.isascii():
             return False
-        if ch.isalnum() or ch in _VALID_QUERY_CHARS:
+        if ch.isalnum() or ch in _VALID_RFC3986_QUERY_CHARS:
             continue
         return False
     return True
@@ -868,8 +868,10 @@ def _unquote(s):
                 raise ValueError("bad query field: %r" % (name_value,))
             if strict_parsing:
                 # Validate RFC3986 characters
-                to_check = (name_value.decode() if isinstance(name_value, bytes) else name_value)
-                if not _is_valid_query(to_check):
+                to_check = _unquote(name_value)
+                if isinstance(to_check, (bytes, bytearray)):
+                    to_check = to_check.decode(encoding, errors)
+                if not _is_valid_rfc3986_query(to_check):
                     raise ValueError(f"Invalid characters in query string per RFC 3986: {name_value!r}")
             if value or keep_blank_values:
                 name = _unquote(name)