S3: Allow in place copies when bucket versioning is enabled (#7303)

Author: arpad-m

moto/s3/models.py

@@ -108,7 +108,7 @@ def __init__(
         storage: Optional[str] = "STANDARD",
         etag: Optional[str] = None,
         is_versioned: bool = False,
-        version_id: str = "null",
+        version_id: Optional[str] = None,
         max_buffer_size: Optional[int] = None,
         multipart: Optional["FakeMultipart"] = None,
         bucket_name: Optional[str] = None,
@@ -170,7 +170,7 @@ def safe_name(self, encoding_type: Optional[str] = None) -> str:
 
     @property
     def version_id(self) -> str:
-        return self._version_id
+        return self._version_id or "null"
 
     @property
     def value(self) -> bytes:
@@ -2674,6 +2674,7 @@ def copy_object(
                     mdirective == "REPLACE",
                     website_redirect_location,
                     bucket.encryption,  # S3 will allow copy in place if the bucket has encryption configured
+                    src_key._version_id and bucket.is_versioned,
                 )
             ):
                 raise CopyObjectMustChangeSomething

tests/test_s3/test_s3_copyobject.py

@@ -783,6 +783,58 @@ def test_copy_object_in_place_with_bucket_encryption():
     assert response["ServerSideEncryption"] == "AES256"
 
 
+@mock_aws
+def test_copy_object_in_place_with_versioning():
+    # If a bucket has versioning enabled, it will allow copy in place
+    client = boto3.client("s3", region_name=DEFAULT_REGION_NAME)
+    bucket_name = "testbucket"
+    client.create_bucket(Bucket=bucket_name)
+    key = "source-key"
+
+    response = client.put_object(
+        Body=b"",
+        Bucket=bucket_name,
+        Key=key,
+    )
+
+    response = client.put_bucket_versioning(
+        Bucket=bucket_name,
+        VersioningConfiguration={
+            "MFADelete": "Disabled",
+            "Status": "Enabled",
+        },
+    )
+    assert response["ResponseMetadata"]["HTTPStatusCode"] == 200
+
+    response = client.put_object(
+        Body=b"",
+        Bucket=bucket_name,
+        Key=key,
+    )
+    version_id = response["ResponseMetadata"]["HTTPHeaders"]["x-amz-version-id"]
+    assert version_id and version_id != "null"
+
+    response = client.copy_object(
+        Bucket=bucket_name,
+        CopySource={"Bucket": bucket_name, "Key": key, "VersionId": version_id},
+        Key=key,
+    )
+    assert response["ResponseMetadata"]["HTTPStatusCode"] == 200
+
+    response = client.copy_object(
+        Bucket=bucket_name,
+        CopySource={"Bucket": bucket_name, "Key": key, "VersionId": "null"},
+        Key=key,
+    )
+    assert response["ResponseMetadata"]["HTTPStatusCode"] == 200
+
+    response = client.list_object_versions(
+        Bucket=bucket_name,
+        Prefix=key,
+    )
+    assert len(response["Versions"]) == 4
+
+
 @mock_aws
 @pytest.mark.parametrize(
     "algorithm",