From 0d022db3e0a4c68b8ad872761f96d520dcacd27f Mon Sep 17 00:00:00 2001
From: Sigurd Spieckermann <sigurd.spieckermann@gmail.com>
Date: Tue, 20 Sep 2022 00:17:40 +0200
Subject: [PATCH 1/3] Fix field regex with StrictStr type annotation

---
 pydantic/types.py   | 16 +++++++++++-----
 tests/test_types.py | 39 +++++++++++++++++++++++++++++++++++++++
 2 files changed, 50 insertions(+), 5 deletions(-)

diff --git a/pydantic/types.py b/pydantic/types.py
index f98dba3de4..1977b8aa17 100644
--- a/pydantic/types.py
+++ b/pydantic/types.py
@@ -403,16 +403,17 @@ class ConstrainedStr(str):
     min_length: OptionalInt = None
     max_length: OptionalInt = None
     curtail_length: OptionalInt = None
-    regex: Optional[Pattern[str]] = None
+    regex: Optional[Union[str, Pattern[str]]] = None
     strict = False
 
     @classmethod
     def __modify_schema__(cls, field_schema: Dict[str, Any]) -> None:
+        regex = cls._regex()
         update_not_none(
             field_schema,
             minLength=cls.min_length,
             maxLength=cls.max_length,
-            pattern=cls.regex and cls.regex.pattern,
+            pattern=regex and regex.pattern,
         )
 
     @classmethod
@@ -429,12 +430,17 @@ def validate(cls, value: Union[str]) -> Union[str]:
         if cls.curtail_length and len(value) > cls.curtail_length:
             value = value[: cls.curtail_length]
 
-        if cls.regex:
-            if not cls.regex.match(value):
-                raise errors.StrRegexError(pattern=cls.regex.pattern)
+        regex = cls._regex()
+        if regex:
+            if not regex.match(value):
+                raise errors.StrRegexError(pattern=regex.pattern)
 
         return value
 
+    @classmethod
+    def _regex(cls) -> Optional[Pattern[str]]:
+        return re.compile(cls.regex) if isinstance(cls.regex, str) else cls.regex
+
 
 def constr(
     *,
diff --git a/tests/test_types.py b/tests/test_types.py
index af4a91ef1d..785e335b91 100644
--- a/tests/test_types.py
+++ b/tests/test_types.py
@@ -1759,6 +1759,45 @@ class Model(BaseModel):
         Model(u='1234567')
 
 
+def test_strict_str_regex():
+    class Model(BaseModel):
+        u: StrictStr = Field(..., regex=r'^[0-9]+$')
+
+    assert Model(u='123').u == '123'
+
+    with pytest.raises(ValidationError, match='str type expected'):
+        Model(u=123)
+
+    with pytest.raises(ValidationError) as exc_info:
+        Model(u='abc')
+    assert exc_info.value.errors() == [
+        {
+            'loc': ('u',),
+            'msg': 'string does not match regex "^[0-9]+$"',
+            'type': 'value_error.str.regex',
+            'ctx': {'pattern': '^[0-9]+$'},
+        }
+    ]
+
+
+def test_string_regex():
+    class Model(BaseModel):
+        u: str = Field(..., regex=r'^[0-9]+$')
+
+    assert Model(u='123').u == '123'
+
+    with pytest.raises(ValidationError) as exc_info:
+        Model(u='abc')
+    assert exc_info.value.errors() == [
+        {
+            'loc': ('u',),
+            'msg': 'string does not match regex "^[0-9]+$"',
+            'type': 'value_error.str.regex',
+            'ctx': {'pattern': '^[0-9]+$'},
+        }
+    ]
+
+
 def test_strict_bool():
     class Model(BaseModel):
         v: StrictBool

From f4e084a80b2b7632a8aa23a12700da0e5e7e952a Mon Sep 17 00:00:00 2001
From: Sigurd Spieckermann <sigurd.spieckermann@gmail.com>
Date: Tue, 20 Sep 2022 00:44:50 +0200
Subject: [PATCH 2/3] Add change file

---
 changes/4538-sisp.md | 1 +
 1 file changed, 1 insertion(+)
 create mode 100644 changes/4538-sisp.md

diff --git a/changes/4538-sisp.md b/changes/4538-sisp.md
new file mode 100644
index 0000000000..afb3312ba5
--- /dev/null
+++ b/changes/4538-sisp.md
@@ -0,0 +1 @@
+Fix field regex with `StrictStr` type annotation.

From 897d4c1fd488089ab747b1b17de6c9e810618821 Mon Sep 17 00:00:00 2001
From: Sigurd Spieckermann <sigurd.spieckermann@gmail.com>
Date: Tue, 20 Sep 2022 12:28:37 +0200
Subject: [PATCH 3/3] Improve regex caching

---
 pydantic/types.py | 16 +++++++---------
 1 file changed, 7 insertions(+), 9 deletions(-)

diff --git a/pydantic/types.py b/pydantic/types.py
index 1977b8aa17..eaf679d48e 100644
--- a/pydantic/types.py
+++ b/pydantic/types.py
@@ -408,12 +408,11 @@ class ConstrainedStr(str):
 
     @classmethod
     def __modify_schema__(cls, field_schema: Dict[str, Any]) -> None:
-        regex = cls._regex()
         update_not_none(
             field_schema,
             minLength=cls.min_length,
             maxLength=cls.max_length,
-            pattern=regex and regex.pattern,
+            pattern=cls.regex and cls._get_pattern(cls.regex),
         )
 
     @classmethod
@@ -430,16 +429,15 @@ def validate(cls, value: Union[str]) -> Union[str]:
         if cls.curtail_length and len(value) > cls.curtail_length:
             value = value[: cls.curtail_length]
 
-        regex = cls._regex()
-        if regex:
-            if not regex.match(value):
-                raise errors.StrRegexError(pattern=regex.pattern)
+        if cls.regex:
+            if not re.match(cls.regex, value):
+                raise errors.StrRegexError(pattern=cls._get_pattern(cls.regex))
 
         return value
 
-    @classmethod
-    def _regex(cls) -> Optional[Pattern[str]]:
-        return re.compile(cls.regex) if isinstance(cls.regex, str) else cls.regex
+    @staticmethod
+    def _get_pattern(regex: Union[str, Pattern[str]]) -> str:
+        return regex if isinstance(regex, str) else regex.pattern
 
 
 def constr(