Don't decode bytes (which may not be UTF8) when displaying SecretBytes (

#8012)

pydantic/types.py

@@ -1495,8 +1495,6 @@ def get_json_schema(_core_schema: core_schema.CoreSchema, handler: GetJsonSchema
 
 
 def _secret_display(value: str | bytes) -> str:
-    if isinstance(value, bytes):
-        value = value.decode()
     return '**********' if value else ''
 
 

tests/test_types.py

@@ -4174,7 +4174,9 @@ class Foobar(BaseModel):
         empty_password: SecretBytes
 
     # Initialize the model.
-    f = Foobar(password=b'wearebytes', empty_password=b'')
+    # Use bytes that can't be decoded with UTF8 (https://github.com/pydantic/pydantic/issues/7971)
+    password = b'\x89PNG\r\n\x1a\n'
+    f = Foobar(password=password, empty_password=b'')
 
     # Assert correct types.
     assert f.password.__class__.__name__ == 'SecretBytes'
@@ -4187,7 +4189,7 @@ class Foobar(BaseModel):
     assert repr(f.empty_password) == "SecretBytes(b'')"
 
     # Assert retrieval of secret value is correct
-    assert f.password.get_secret_value() == b'wearebytes'
+    assert f.password.get_secret_value() == password
     assert f.empty_password.get_secret_value() == b''
 
     # Assert that SecretBytes is equal to SecretBytes if the secret is the same.