fix(python): Require exact checking for Decimals in assertion utils (#…

…14357)

py-polars/polars/testing/asserts/series.py

@@ -6,8 +6,6 @@
     FLOAT_DTYPES,
     Array,
     Categorical,
-    Decimal,
-    Float64,
     List,
     String,
     Struct,
@@ -129,14 +127,6 @@ def _assert_series_values_equal(
         if right.dtype == Categorical:
             right = right.cast(String)
 
-    # Handle decimals
-    # TODO: Delete this branch when Decimal equality is implemented
-    # https://github.com/pola-rs/polars/issues/12118
-    if left.dtype == Decimal:
-        left = left.cast(Float64)
-    if right.dtype == Decimal:
-        right = right.cast(Float64)
-
     # Determine unequal elements
     try:
         unequal = left.ne_missing(right)

py-polars/tests/unit/testing/test_assert_series_equal.py

@@ -619,24 +619,16 @@ def test_series_equal_nested_lengths_mismatch() -> None:
         assert_series_equal(s1, s2)
 
 
-def test_series_equal_decimals_exact() -> None:
-    s1 = pl.Series([D("1.00000"), D("2.00000")], dtype=pl.Decimal)
-    s2 = pl.Series([D("1.00000"), D("2.00001")], dtype=pl.Decimal)
-    with pytest.raises(AssertionError, match="exact value mismatch"):
-        assert_series_equal(s1, s2, check_exact=True)
-
-
-def test_series_equal_decimals_inexact() -> None:
+@pytest.mark.parametrize("check_exact", [True, False])
+def test_series_equal_decimals(check_exact: bool) -> None:
     s1 = pl.Series([D("1.00000"), D("2.00000")], dtype=pl.Decimal)
     s2 = pl.Series([D("1.00000"), D("2.00001")], dtype=pl.Decimal)
-    assert_series_equal(s1, s2, check_exact=False)
 
+    assert_series_equal(s1, s1, check_exact=check_exact)
+    assert_series_equal(s2, s2, check_exact=check_exact)
 
-def test_series_equal_decimals_inexact_fail() -> None:
-    s1 = pl.Series([D("1.00000"), D("2.00000")], dtype=pl.Decimal)
-    s2 = pl.Series([D("1.00000"), D("2.00001")], dtype=pl.Decimal)
-    with pytest.raises(AssertionError, match="value mismatch"):
-        assert_series_equal(s1, s2, check_exact=False, rtol=0)
+    with pytest.raises(AssertionError, match="exact value mismatch"):
+        assert_series_equal(s1, s2, check_exact=check_exact)
 
 
 def test_assert_series_equal_w_large_integers_12328() -> None: