not raise error when partion_on is used in fastparquet

add a blank line before the versionadded

Author: anjsudh

pandas/core/frame.py

@@ -2004,6 +2004,7 @@ def to_parquet(self, fname, engine='auto', compression='snappy',
             Columns are partitioned in the order they are given
             The behaviour applies only to pyarrow >= 0.7.0 and fastparquet
             For other versions, this argument will be ignored.
+
             .. versionadded:: 0.24.0
 
         **kwargs

pandas/io/parquet.py

@@ -225,7 +225,8 @@ def write(self, df, path, compression='snappy', index=None,
         # Use tobytes() instead.
 
         if 'partition_on' in kwargs:
-            raise ValueError("must use 'partition_cols' instead of 'partition_on'")
+            partition_cols = kwargs['partition_on']
+            del kwargs['partition_on']
 
         if partition_cols is not None:
             kwargs['file_scheme'] = 'hive'

pandas/tests/io/test_parquet.py

@@ -491,15 +491,14 @@ def test_partition_cols_supported(self, pa_ge_070, df_full):
             assert len(dataset.partitions.partition_names) == 2
             assert dataset.partitions.partition_names == set(partition_cols)
 
-    def test_ignore_partition_cols_lt_070(self, pa_lt_070, df_full):
+    def test_partition_cols_not_supported_pa_lt_70(self, pa_lt_070, df_full):
         # GH #23283
         partition_cols = ['bool', 'int']
-        pa = pa_lt_070
         df = df_full
-        with tm.ensure_clean_dir() as path:
-            df.to_parquet(path, partition_cols=partition_cols,
-                          compression=None)
-        pytest.raises(ValueError)
+        with pytest.raises(ValueError):
+            with tm.ensure_clean_dir() as path:
+                df.to_parquet(path, partition_cols=partition_cols,
+                              compression=None)
 
 
 class TestParquetFastParquet(Base):
@@ -572,17 +571,21 @@ def test_partition_cols_supported(self, fp, df_full):
         partition_cols = ['bool', 'int']
         df = df_full
         with tm.ensure_clean_dir() as path:
-            df.to_parquet(path, partition_cols=partition_cols,
-                          compression=None)
+            df.to_parquet(path, engine="fastparquet",
+                          partition_cols=partition_cols, compression=None)
             assert os.path.exists(path)
             import fastparquet
             actual_partition_cols = fastparquet.ParquetFile(path, False).cats
             assert len(actual_partition_cols) == 2
 
-    def test_partition_on_not_supported(self, fp, df_full):
+    def test_partition_on_supported(self, fp, df_full):
         # GH #23283
         partition_cols = ['bool', 'int']
         df = df_full
-        with pytest.raises(ValueError):
-            df.to_parquet("", compression=None,
-              partition_on=partition_cols)
+        with tm.ensure_clean_dir() as path:
+            df.to_parquet(path, engine="fastparquet", compression=None,
+                          partition_on=partition_cols)
+            assert os.path.exists(path)
+            import fastparquet
+            actual_partition_cols = fastparquet.ParquetFile(path, False).cats
+            assert len(actual_partition_cols) == 2