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BUG: read_csv with pyarrow engine cannot handle single-line CSV files #62643

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BUG: read_csv with pyarrow engine cannot handle single-line CSV files #62643

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b613a16
Fix bug read_csv with pyarrow engine cannot handle single-line CSV files
khemkaran10 Oct 10, 2025
ddeaafd
Merge remote-tracking branch 'upstream/main' into issue_62635
khemkaran10 Oct 10, 2025
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1 change: 1 addition & 0 deletions pandas/io/parsers/arrow_parser_wrapper.py
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Original file line number Diff line number Diff line change
Expand Up @@ -140,6 +140,7 @@ def handle_warning(invalid_row) -> str:
]

self.read_options = {
"column_names": [] if self.header is None else self.kwds["names"],
"autogenerate_column_names": self.header is None,
"skip_rows": self.header
if self.header is not None
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11 changes: 11 additions & 0 deletions pandas/tests/io/parser/common/test_common_basic.py
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Expand Up @@ -119,6 +119,17 @@ def test_csv_mixed_type(all_parsers):
tm.assert_frame_equal(result, expected)


def test_read_csv_single_line(all_parsers):
# GH62635
parser = all_parsers
table = parser.read_csv(
StringIO("1,2,3\n"),
names=["col1", "col2", "col3"],
)
expected = DataFrame({"col1": [1], "col2": [2], "col3": [3]})
tm.assert_frame_equal(table, expected)


def test_read_csv_low_memory_no_rows_with_index(all_parsers):
# see gh-21141
parser = all_parsers
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