feat(python): implement __repr__ for CellError and CellErrors (#461)

relates to #458

Signed-off-by: Luka Peschke <luka.peschke@toucantoco.com>

Author: lukapeschke

python/fastexcel/_fastexcel.pyi

@@ -76,10 +76,12 @@ class CellError:
     def offset_position(self) -> tuple[int, int]: ...
     @property
     def detail(self) -> str: ...
+    def __repr__(self) -> str: ...
 
 class CellErrors:
     @property
     def errors(self) -> list[CellError]: ...
+    def __repr__(self) -> str: ...
 
 class _ExcelSheet:
     @property

python/tests/test_errors.py

@@ -6,6 +6,16 @@
 from .utils import path_for_fixture
 
 
+def test_cell_error_repr() -> None:
+    excel_reader = fastexcel.read_excel(path_for_fixture("fixture-type-errors.xlsx"))
+    _, cell_errors = excel_reader.load_sheet(0, dtypes={"Column": "int"}).to_arrow_with_errors()
+    assert cell_errors is not None
+    assert (
+        repr(cell_errors.errors[0])
+        == """CellError(position=(2, 0), offset_position=(1, 0), row_offset=1, detail="Expected int but got 'String(\\"foo\\")'")"""  # noqa: E501
+    )
+
+
 def test_read_excel_bad_type() -> None:
     expected_message = "source must be a string or bytes"
     with pytest.raises(fastexcel.InvalidParametersError, match=expected_message):

src/types/excelsheet/python.rs

@@ -142,6 +142,16 @@ impl CellError {
         let (row, col) = self.position;
         (row - self.row_offset, col)
     }
+
+    pub fn __repr__(&self) -> String {
+        let (row, col) = self.position;
+        let (offset_row, offset_col) = self.offset_position();
+        format!(
+            "CellError(position=({row}, {col}), offset_position=({offset_row}, {offset_col}), row_offset={row_offset}, detail={detail:?})",
+            row_offset = self.row_offset,
+            detail = &self.detail,
+        )
+    }
 }
 
 #[pyclass]
@@ -155,6 +165,11 @@ impl CellErrors {
     pub fn errors<'p>(&'p self, _py: Python<'p>) -> Vec<CellError> {
         self.errors.clone()
     }
+
+    pub fn __repr__(&self) -> String {
+        let errors_repr: Vec<String> = self.errors.iter().map(|e| e.__repr__()).collect();
+        format!("CellErrors(errors=[{}])", errors_repr.join(", "))
+    }
 }
 
 impl FromPyObject<'_> for SkipRows {