feat: support assigning to columns like a property (#304)

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Fixes #<issue_number_goes_here> 🦕

Author: TrevorBergeron

bigframes/core/log_adapter.py

@@ -19,12 +19,13 @@
 _lock = threading.Lock()
 MAX_LABELS_COUNT = 64
 _api_methods: List = []
+_excluded_methods = ["__setattr__", "__getattr__"]
 
 
 def class_logger(decorated_cls):
     """Decorator that adds logging functionality to each method of the class."""
     for attr_name, attr_value in decorated_cls.__dict__.items():
-        if callable(attr_value):
+        if callable(attr_value) and (attr_name not in _excluded_methods):
             setattr(decorated_cls, attr_name, method_logger(attr_value, decorated_cls))
     return decorated_cls
 

bigframes/dataframe.py

@@ -251,6 +251,15 @@ def index(
     ) -> indexes.Index:
         return indexes.Index(self)
 
+    @index.setter
+    def index(self, value):
+        # TODO: Handle assigning MultiIndex
+        result = self._assign_single_item("_new_bf_index", value).set_index(
+            "_new_bf_index"
+        )
+        self._set_block(result._get_block())
+        self.index.name = value.name if hasattr(value, "name") else None
+
     @property
     def loc(self) -> indexers.LocDataFrameIndexer:
         return indexers.LocDataFrameIndexer(self)
@@ -545,6 +554,29 @@ def __getattr__(self, key: str):
         else:
             raise AttributeError(key)
 
+    def __setattr__(self, key: str, value):
+        if key in ["_block", "_query_job"]:
+            object.__setattr__(self, key, value)
+            return
+        # Can this be removed???
+        try:
+            # boring attributes go through boring old path
+            object.__getattribute__(self, key)
+            return object.__setattr__(self, key, value)
+        except AttributeError:
+            pass
+
+        # if this fails, go on to more involved attribute setting
+        # (note that this matches __getattr__, above).
+        try:
+            if key in self.columns:
+                self[key] = value
+            else:
+                object.__setattr__(self, key, value)
+        # Can this be removed?
+        except (AttributeError, TypeError):
+            object.__setattr__(self, key, value)
+
     def __repr__(self) -> str:
         """Converts a DataFrame to a string. Calls to_pandas.
 
@@ -1265,6 +1297,15 @@ def _assign_single_item_listlike(self, k: str, v: Sequence) -> DataFrame:
                 [get_column_left[col_id] for col_id in original_index_column_ids],
                 index_labels=self._block.index_labels,
             )
+            src_col = get_column_right[new_column_block.value_columns[0]]
+            # Check to see if key exists, and modify in place
+            col_ids = self._block.cols_matching_label(k)
+            for col_id in col_ids:
+                result_block = result_block.copy_values(
+                    src_col, get_column_left[col_id]
+                )
+            if len(col_ids) > 0:
+                result_block = result_block.drop_columns([src_col])
         return DataFrame(result_block)
 
     def _assign_scalar(self, label: str, value: Union[int, float]) -> DataFrame:

bigframes/series.py

@@ -139,6 +139,10 @@ def struct(self) -> structs.StructAccessor:
     def T(self) -> Series:
         return self.transpose()
 
+    @property
+    def _info_axis(self) -> indexes.Index:
+        return self.index
+
     def transpose(self) -> Series:
         return self
 

tests/system/small/test_dataframe.py

@@ -3140,17 +3140,65 @@ def test_df___array__(scalars_df_index, scalars_pandas_df_index):
     )
 
 
-def test_getattr_attribute_error_when_pandas_has(scalars_df_index):
+def test_df_getattr_attribute_error_when_pandas_has(scalars_df_index):
     # swapaxes is implemented in pandas but not in bigframes
     with pytest.raises(AttributeError):
         scalars_df_index.swapaxes()
 
 
-def test_getattr_attribute_error(scalars_df_index):
+def test_df_getattr_attribute_error(scalars_df_index):
     with pytest.raises(AttributeError):
         scalars_df_index.not_a_method()
 
 
+def test_df_getattr_axes():
+    df = dataframe.DataFrame(
+        [[1, 1, 1], [1, 1, 1]], columns=["index", "columns", "my_column"]
+    )
+    assert isinstance(df.index, bigframes.core.indexes.Index)
+    assert isinstance(df.columns, pandas.Index)
+    assert isinstance(df.my_column, series.Series)
+
+
+def test_df_setattr_index():
+    pd_df = pandas.DataFrame(
+        [[1, 1, 1], [1, 1, 1]], columns=["index", "columns", "my_column"]
+    )
+    bf_df = dataframe.DataFrame(pd_df)
+    pd_df.index = [4, 5]
+    bf_df.index = [4, 5]
+
+    assert_pandas_df_equal(
+        pd_df, bf_df.to_pandas(), check_index_type=False, check_dtype=False
+    )
+
+
+def test_df_setattr_columns():
+    pd_df = pandas.DataFrame(
+        [[1, 1, 1], [1, 1, 1]], columns=["index", "columns", "my_column"]
+    )
+    bf_df = dataframe.DataFrame(pd_df)
+    pd_df.columns = [4, 5, 6]
+    bf_df.columns = [4, 5, 6]
+
+    assert_pandas_df_equal(
+        pd_df, bf_df.to_pandas(), check_index_type=False, check_dtype=False
+    )
+
+
+def test_df_setattr_modify_column():
+    pd_df = pandas.DataFrame(
+        [[1, 1, 1], [1, 1, 1]], columns=["index", "columns", "my_column"]
+    )
+    bf_df = dataframe.DataFrame(pd_df)
+    pd_df.my_column = [4, 5]
+    bf_df.my_column = [4, 5]
+
+    assert_pandas_df_equal(
+        pd_df, bf_df.to_pandas(), check_index_type=False, check_dtype=False
+    )
+
+
 def test_loc_list_string_index(scalars_df_index, scalars_pandas_df_index):
     index_list = scalars_pandas_df_index.string_col.iloc[[0, 1, 1, 5]].values