Repository: googleapis/python-storage

Issue:
'Blob.custom_time' setter doesnt update '_changes'
i think the `custom_time setter` code should be:

```python
        self._patch_property('customTime', value)
```

instead of 

```python
        self._properties["customTime"] = value
```

Discussion:
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haim0n: > Thanks for the patch. Please add unit test assertions (as I did in PR #325, which I am closing in favor of this one).

done

Patch:
diff --git a/google/cloud/storage/blob.py b/google/cloud/storage/blob.py
index 18006d5..38da243 100644
--- a/google/cloud/storage/blob.py
+++ b/google/cloud/storage/blob.py
@@ -3613,7 +3613,7 @@ class Blob(_PropertyMixin):
         if value is not None:
             value = _datetime_to_rfc3339(value)
 
-        self._properties["customTime"] = value
+        self._patch_property("customTime", value)
 
 
 def _get_encryption_headers(key, source=False):


Test patch:
diff --git a/tests/unit/test_blob.py b/tests/unit/test_blob.py
index bc99186..5f93bc2 100644
--- a/tests/unit/test_blob.py
+++ b/tests/unit/test_blob.py
@@ -3987,6 +3987,7 @@ class Test_Blob(unittest.TestCase):
             if_generation_match=GENERATION_NUMBER,
             if_source_generation_match=SOURCE_GENERATION_NUMBER,
         )
+
         self.assertEqual(blob.storage_class, "NEARLINE")
 
         kw = connection._requested
@@ -4236,6 +4237,7 @@ class Test_Blob(unittest.TestCase):
         self.assertIsNone(blob.metadata)
         blob.metadata = METADATA
         self.assertEqual(blob.metadata, METADATA)
+        self.assertIn("metadata", blob._changes)
 
     def test_metadata_setter_w_nan(self):
         BLOB_NAME = "blob-name"
@@ -4246,6 +4248,7 @@ class Test_Blob(unittest.TestCase):
         blob.metadata = METADATA
         value = blob.metadata["foo"]
         self.assertIsInstance(value, str)
+        self.assertIn("metadata", blob._changes)
 
     def test_metageneration(self):
         BUCKET = object()
@@ -4444,6 +4447,7 @@ class Test_Blob(unittest.TestCase):
         self.assertIsNone(blob.custom_time)
         blob.custom_time = TIMESTAMP
         self.assertEqual(blob.custom_time, TIMESTAMP)
+        self.assertIn("customTime", blob._changes)
 
     def test_custom_time_setter_none_value(self):
         from google.cloud._helpers import _RFC3339_MICROS