Add tests for new reader and writer api (#17)

Author: yuzelin

paimon_python_java/tests/test_write_and_read.py

@@ -219,3 +219,81 @@ def testParallelRead(self):
         # check data (ignore index)
         pd.testing.assert_frame_equal(
             result.reset_index(drop=True), expected_df.reset_index(drop=True))
+
+    def testAllWriteAndReadApi(self):
+        schema = Schema(self.simple_pa_schema)
+        self.catalog.create_table('default.test_all_api', schema, False)
+        table = self.catalog.get_table('default.test_all_api')
+        write_builder = table.new_batch_write_builder()
+
+        # write_arrow
+        table_write = write_builder.new_write()
+        table_commit = write_builder.new_commit()
+        data1 = {
+            'f0': [1, 2, 3],
+            'f1': ['a', 'b', 'c'],
+        }
+        pa_table = pa.Table.from_pydict(data1, schema=self.simple_pa_schema)
+        table_write.write_arrow(pa_table)
+        table_commit.commit(table_write.prepare_commit())
+        table_write.close()
+        table_commit.close()
+
+        # write_arrow_batch
+        table_write = write_builder.new_write()
+        table_commit = write_builder.new_commit()
+        data2 = {
+            'f0': [4, 5, 6],
+            'f1': ['d', 'e', 'f'],
+        }
+        df = pd.DataFrame(data2)
+        record_batch = pa.RecordBatch.from_pandas(df, schema=self.simple_pa_schema)
+        table_write.write_arrow_batch(record_batch)
+        table_commit.commit(table_write.prepare_commit())
+        table_write.close()
+        table_commit.close()
+
+        # write_pandas
+        table_write = write_builder.new_write()
+        table_commit = write_builder.new_commit()
+        data3 = {
+            'f0': [7, 8, 9],
+            'f1': ['g', 'h', 'i'],
+        }
+        df = pd.DataFrame(data3)
+        table_write.write_pandas(df)
+        table_commit.commit(table_write.prepare_commit())
+        table_write.close()
+        table_commit.close()
+
+        read_builder = table.new_read_builder()
+        table_scan = read_builder.new_scan()
+        table_read = read_builder.new_read()
+        splits = table_scan.plan().splits()
+
+        # to_arrow
+        actual = table_read.to_arrow(splits)
+        expected = pa.Table.from_pydict({
+            'f0': [1, 2, 3, 4, 5, 6, 7, 8, 9],
+            'f1': ['a', 'b', 'c', 'd', 'e', 'f', 'g', 'h', 'i'],
+        }, schema=self.simple_pa_schema)
+        self.assertEqual(actual, expected)
+
+        # to_arrow_batch_reader
+        data_frames = [
+            batch.to_pandas()
+            for batch in table_read.to_arrow_batch_reader(splits)
+        ]
+        actual = pd.concat(data_frames)
+        expected = pd.DataFrame({
+            'f0': [1, 2, 3, 4, 5, 6, 7, 8, 9],
+            'f1': ['a', 'b', 'c', 'd', 'e', 'f', 'g', 'h', 'i'],
+        })
+        expected['f0'] = expected['f0'].astype('int32')
+        pd.testing.assert_frame_equal(
+            actual.reset_index(drop=True), expected.reset_index(drop=True))
+
+        # to_pandas
+        actual = table_read.to_pandas(splits)
+        pd.testing.assert_frame_equal(
+            actual.reset_index(drop=True), expected.reset_index(drop=True))