GH-47389: [Python] CSV and JSON options lack a nice repr/str (#47397)

thisisnic · AlenkaF · web-flow · commit 618d5fbe84ba · 2026-03-25T09:38:36.000+01:00
### Rationale for this change CSV and JSON options lack a nice repr/str dunder method ### What changes are included in this PR? Add both these methods ### Are these changes tested? Will be once it's ready for review ### Are there any user-facing changes? No * GitHub Issue: #47389 Lead-authored-by: Nic Crane <thisisnic@gmail.com> Co-authored-by: AlenkaF <frim.alenka@gmail.com> Co-authored-by: Alenka Frim <AlenkaF@users.noreply.github.com> Signed-off-by: AlenkaF <frim.alenka@gmail.com>
diff --git a/python/pyarrow/_csv.pyx b/python/pyarrow/_csv.pyx
@@ -332,6 +332,22 @@ cdef class ReadOptions(_Weakrefable):
         except TypeError:
             return False
 
+    def _repr_base(self):
+        return (f"""
+    use_threads={self.use_threads},
+    block_size={self.block_size},
+    skip_rows={self.skip_rows},
+    skip_rows_after_names={self.skip_rows_after_names},
+    column_names={self.column_names},
+    autogenerate_column_names={self.autogenerate_column_names},
+    encoding={self.encoding!r}""")
+
+    def __repr__(self):
+        return (f"<pyarrow.csv.ReadOptions>({self._repr_base()})")
+
+    def __str__(self):
+        return (f"ReadOptions({self._repr_base()})")
+
 
 cdef class ParseOptions(_Weakrefable):
     """
@@ -585,6 +601,23 @@ cdef class ParseOptions(_Weakrefable):
         except TypeError:
             return False
 
+    def _repr_base(self):
+        return (f"""
+    delimiter={self.delimiter!r},
+    quote_char={self.quote_char!r},
+    double_quote={self.double_quote},
+    escape_char={self.escape_char!r},
+    newlines_in_values={self.newlines_in_values},
+    ignore_empty_lines={self.ignore_empty_lines},
+    invalid_row_handler={getattr(self.invalid_row_handler, '__name__',
+                                 self.invalid_row_handler)}""")
+
+    def __repr__(self):
+        return (f"<pyarrow.csv.ParseOptions>({self._repr_base()})")
+
+    def __str__(self):
+        return (f"ParseOptions({self._repr_base()})")
+
 
 cdef class _ISO8601(_Weakrefable):
     """
@@ -1108,6 +1141,28 @@ cdef class ConvertOptions(_Weakrefable):
         except TypeError:
             return False
 
+    def _repr_base(self):
+        return (f"""
+    check_utf8={self.check_utf8},
+    column_types={self.column_types},
+    null_values={self.null_values},
+    true_values={self.true_values},
+    false_values={self.false_values},
+    decimal_point={self.decimal_point!r},
+    strings_can_be_null={self.strings_can_be_null},
+    quoted_strings_can_be_null={self.quoted_strings_can_be_null},
+    include_columns={self.include_columns},
+    include_missing_columns={self.include_missing_columns},
+    auto_dict_encode={self.auto_dict_encode},
+    auto_dict_max_cardinality={self.auto_dict_max_cardinality},
+    timestamp_parsers={[str(i) for i in self.timestamp_parsers]}""")
+
+    def __repr__(self):
+        return (f"<pyarrow.csv.ConvertOptions>({self._repr_base()})")
+
+    def __str__(self):
+        return (f"ConvertOptions({self._repr_base()})")
+
 
 cdef _get_reader(input_file, ReadOptions read_options,
                  shared_ptr[CInputStream]* out):
@@ -1459,6 +1514,19 @@ cdef class WriteOptions(_Weakrefable):
     def validate(self):
         check_status(self.options.get().Validate())
 
+    def _repr_base(self):
+        return (f"""
+    include_header={self.include_header},
+    batch_size={self.batch_size},
+    delimiter={self.delimiter!r},
+    quoting_style={self.quoting_style!r}""")
+
+    def __repr__(self):
+        return (f"<pyarrow.csv.WriteOptions>({self._repr_base()})")
+
+    def __str__(self):
+        return (f"WriteOptions({self._repr_base()})")
+
 
 cdef _get_write_options(WriteOptions write_options, CCSVWriteOptions* out):
     if write_options is None:
diff --git a/python/pyarrow/_json.pyx b/python/pyarrow/_json.pyx
@@ -105,6 +105,16 @@ cdef class ReadOptions(_Weakrefable):
         except TypeError:
             return False
 
+    def __repr__(self):
+        return (f"""<pyarrow.json.ReadOptions>(
+    use_threads={self.use_threads},
+    block_size={self.block_size})""")
+
+    def __str__(self):
+        return (f"""ReadOptions(
+    use_threads={self.use_threads},
+    block_size={self.block_size})""")
+
     @staticmethod
     cdef ReadOptions wrap(CJSONReadOptions options):
         out = ReadOptions()
@@ -244,6 +254,18 @@ cdef class ParseOptions(_Weakrefable):
         except TypeError:
             return False
 
+    def _repr_base(self):
+        return (f"""
+    explicit_schema={self.explicit_schema},
+    newlines_in_values={self.newlines_in_values},
+    unexpected_field_behavior={self.unexpected_field_behavior!r}""")
+
+    def __repr__(self):
+        return (f"<pyarrow.json.ParseOptions>({self._repr_base()})")
+
+    def __str__(self):
+        return (f"ParseOptions({self._repr_base()})")
+
     @staticmethod
     cdef ParseOptions wrap(CJSONParseOptions options):
         out = ParseOptions()
diff --git a/python/pyarrow/tests/test_csv.py b/python/pyarrow/tests/test_csv.py
@@ -213,6 +213,18 @@ def test_read_options(pickle_module):
         opts.column_names = ('a', 'b')
         opts.validate()
 
+    expected_repr_inner = """
+    use_threads=True,
+    block_size=1048576,
+    skip_rows=0,
+    skip_rows_after_names=0,
+    column_names=['a', 'b'],
+    autogenerate_column_names=True,
+    encoding='utf8'"""
+
+    assert repr(opts) == f"<pyarrow.csv.ReadOptions>({expected_repr_inner})"
+    assert str(opts) == f"ReadOptions({expected_repr_inner})"
+
 
 def test_parse_options(pickle_module):
     cls = ParseOptions
@@ -273,6 +285,18 @@ def test_parse_options(pickle_module):
         opts.escape_char = "\r"
         opts.validate()
 
+    expected_repr_inner = r"""
+    delimiter=',',
+    quote_char='"',
+    double_quote=True,
+    escape_char='\r',
+    newlines_in_values=False,
+    ignore_empty_lines=True,
+    invalid_row_handler=None"""
+
+    assert repr(opts) == f"<pyarrow.csv.ParseOptions>({expected_repr_inner})"
+    assert str(opts) == f"ParseOptions({expected_repr_inner})"
+
 
 def test_convert_options(pickle_module):
     cls = ConvertOptions
@@ -354,6 +378,23 @@ def test_convert_options(pickle_module):
     assert opts.auto_dict_max_cardinality == 999
     assert opts.timestamp_parsers == [ISO8601, '%Y-%m-%d']
 
+    expected_repr_inner = ("""
+    check_utf8=True,
+    column_types={'a': DataType(null)},
+    null_values=['N', 'nn'],
+    true_values=['T', 'tt'],
+    false_values=['F', 'ff'],
+    decimal_point='.',
+    strings_can_be_null=False,
+    quoted_strings_can_be_null=True,
+    include_columns=[],
+    include_missing_columns=False,
+    auto_dict_encode=False,
+    auto_dict_max_cardinality=999,
+    timestamp_parsers=['ISO8601', '%Y-%m-%d']""")
+    assert repr(opts) == f"<pyarrow.csv.ConvertOptions>({expected_repr_inner})"
+    assert str(opts) == f"ConvertOptions({expected_repr_inner})"
+
 
 def test_write_options():
     cls = WriteOptions
@@ -378,6 +419,15 @@ def test_write_options():
         opts.batch_size = 0
         opts.validate()
 
+    expected_repr_inner = """
+    include_header=True,
+    batch_size=0,
+    delimiter=',',
+    quoting_style='needed'"""
+
+    assert repr(opts) == f"<pyarrow.csv.WriteOptions>({expected_repr_inner})"
+    assert str(opts) == f"WriteOptions({expected_repr_inner})"
+
 
 class BaseTestCSV(abc.ABC):
     """Common tests which are shared by streaming and non streaming readers"""
diff --git a/python/pyarrow/tests/test_json.py b/python/pyarrow/tests/test_json.py
@@ -80,6 +80,13 @@ def test_read_options(pickle_module):
     assert opts.block_size == 1234
     assert opts.use_threads is False
 
+    expected_repr_inner = """
+    use_threads=False,
+    block_size=1234"""
+
+    assert repr(opts) == f"<pyarrow.json.ReadOptions>({expected_repr_inner})"
+    assert str(opts) == f"ReadOptions({expected_repr_inner})"
+
     check_options_class_pickling(cls, pickler=pickle_module,
                                  block_size=1234,
                                  use_threads=False)
@@ -94,6 +101,14 @@ def test_parse_options(pickle_module):
     opts.newlines_in_values = True
     assert opts.newlines_in_values is True
 
+    expected_repr_inner = """
+    explicit_schema=None,
+    newlines_in_values=True,
+    unexpected_field_behavior='infer'"""
+
+    assert repr(opts) == f"<pyarrow.json.ParseOptions>({expected_repr_inner})"
+    assert str(opts) == f"ParseOptions({expected_repr_inner})"
+
     schema = pa.schema([pa.field('foo', pa.int32())])
     opts.explicit_schema = schema
     assert opts.explicit_schema == schema
