From 54568aeb967187cd5ef910881cf0594f3a170179 Mon Sep 17 00:00:00 2001
From: dchhh <hudacong@geetest.com>
Date: Thu, 21 May 2020 21:47:41 +0800
Subject: [PATCH 1/3] fix issure #1155

---
 pydantic/fields.py       |  8 ++++----
 tests/test_validators.py | 19 +++++++++++++++++++
 2 files changed, 23 insertions(+), 4 deletions(-)

diff --git a/pydantic/fields.py b/pydantic/fields.py
index c49ad7f047..37f8c1ea8b 100644
--- a/pydantic/fields.py
+++ b/pydantic/fields.py
@@ -354,10 +354,6 @@ def prepare(self) -> None:
             # user will need to call model.update_forward_refs()
             return
 
-        self.validate_always = getattr(self.type_, 'validate_always', False) or any(
-            v.always for v in self.class_validators.values()
-        )
-
         if self.required is False and default_value is None:
             self.allow_none = True
 
@@ -500,6 +496,10 @@ def populate_validators(self) -> None:
         and class validators. This method should be idempotent, e.g. it should be safe to call multiple times
         without mis-configuring the field.
         """
+        self.validate_always = getattr(self.type_, 'validate_always', False) or any(
+            v.always for v in self.class_validators.values()
+        )
+
         class_validators_ = self.class_validators.values()
         if not self.sub_fields or self.shape == SHAPE_GENERIC:
             get_validators = getattr(self.type_, '__get_validators__', None)
diff --git a/tests/test_validators.py b/tests/test_validators.py
index 386fbbeb77..28d05c62e3 100644
--- a/tests/test_validators.py
+++ b/tests/test_validators.py
@@ -286,6 +286,25 @@ def check_a(cls, v):
     assert check_calls == 2
 
 
+def test_validate_always_on_inheritance():
+    check_calls = 0
+
+    class ParentModel(BaseModel):
+        a: str = None
+
+    class Model(ParentModel):
+        @validator('a', pre=True, always=True)
+        def check_a(cls, v):
+            nonlocal check_calls
+            check_calls += 1
+            return v or 'xxx'
+
+    assert Model().a == 'xxx'
+    assert check_calls == 1
+    assert Model(a='y').a == 'y'
+    assert check_calls == 2
+
+
 def test_validate_not_always():
     check_calls = 0
 

From 627948591cae54330b3ba812d8c5cf56b15a3641 Mon Sep 17 00:00:00 2001
From: dchhh <hudacong@geetest.com>
Date: Sun, 28 Jun 2020 23:35:53 +0800
Subject: [PATCH 2/3] add changes.1545-dcHHH.md

---
 changes/1545-dcHHH.md | 1 +
 1 file changed, 1 insertion(+)
 create mode 100644 changes/1545-dcHHH.md

diff --git a/changes/1545-dcHHH.md b/changes/1545-dcHHH.md
new file mode 100644
index 0000000000..748509f171
--- /dev/null
+++ b/changes/1545-dcHHH.md
@@ -0,0 +1 @@
+Move the assignment of field.validate_always in fields.py to make 'always' parameter of validator works on inheritance.
\ No newline at end of file

From 0d5caf2f8afc5e0b2f7e56be8889eaa9128da09d Mon Sep 17 00:00:00 2001
From: Samuel Colvin <samcolvin@gmail.com>
Date: Mon, 29 Jun 2020 09:26:13 +0100
Subject: [PATCH 3/3] improve change description

---
 changes/1545-dcHHH.md | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/changes/1545-dcHHH.md b/changes/1545-dcHHH.md
index 748509f171..a5ccad5f78 100644
--- a/changes/1545-dcHHH.md
+++ b/changes/1545-dcHHH.md
@@ -1 +1 @@
-Move the assignment of field.validate_always in fields.py to make 'always' parameter of validator works on inheritance.
\ No newline at end of file
+Move the assignment of `field.validate_always` in `fields.py` so the `always` parameter of validators work on inheritance.