fix[python]: fix "assert_series_equal" for specific arrangements of n…

…ull (#4683)
pola-rs · Sep 2, 2022 · 383fdb7 · 383fdb7
1 parent 0f60051
commit 383fdb7
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Showing 3 changed files with 25 additions and 5 deletions.
diff --git a/py-polars/polars/testing.py b/py-polars/polars/testing.py
@@ -257,7 +257,9 @@ def _assert_series_inner(
         else:
             # apply check with tolerance, but only to the known-unequal matches
             left, right = left.filter(unequal), right.filter(unequal)
-            if ((left - right).abs() > (atol + rtol * right.abs())).sum() != 0:
+            if (((left - right).abs() > (atol + rtol * right.abs())).sum() != 0) or (
+                (left.is_null() != right.is_null()).any()
+            ):
                 raise_assert_detail(
                     obj, "Value mismatch", left=list(left), right=list(right)
                 )

diff --git a/py-polars/tests/test_series.py b/py-polars/tests/test_series.py
@@ -1873,9 +1873,20 @@ def test_exp() -> None:
 
 def test_cumulative_eval() -> None:
     s = pl.Series("values", [1, 2, 3, 4, 5])
-    expr = pl.element().first() - pl.element().last() ** 2
-    expected = pl.Series("values", [None, -3.0, -8.0, -15.0, -24.0])
-    verify_series_and_expr_api(s, expected, "cumulative_eval", expr)
+
+    # evaluate expressions individually
+    expr1 = pl.element().first()
+    expr2 = pl.element().last() ** 2
+
+    expected1 = pl.Series("values", [1, 1, 1, 1, 1])
+    expected2 = pl.Series("values", [1.0, 4.0, 9.0, 16.0, 25.0])
+    verify_series_and_expr_api(s, expected1, "cumulative_eval", expr1)
+    verify_series_and_expr_api(s, expected2, "cumulative_eval", expr2)
+
+    # evaluate combined expressions and validate
+    expr3 = expr1 - expr2
+    expected3 = pl.Series("values", [0.0, -3.0, -8.0, -15.0, -24.0])
+    verify_series_and_expr_api(s, expected3, "cumulative_eval", expr3)
 
 
 def test_drop_nan_ignore_null_3525() -> None:

diff --git a/py-polars/tests/test_testing.py b/py-polars/tests/test_testing.py
@@ -33,11 +33,18 @@ def test_compare_series_nans_assert_equal() -> None:
         assert_series_equal(srs1, srs2, check_exact=True)
 
 
-def test_compare_series_nulls_are_equal() -> None:
+def test_compare_series_nulls() -> None:
     srs1 = pl.Series([1, 2, None])
     srs2 = pl.Series([1, 2, None])
     assert_series_equal(srs1, srs2)
 
+    srs1 = pl.Series([1, 2, 3])
+    srs2 = pl.Series([1, None, None])
+    with pytest.raises(AssertionError, match="Value mismatch"):
+        assert_series_equal(srs1, srs2)
+    with pytest.raises(AssertionError, match="Exact value mismatch"):
+        assert_series_equal(srs1, srs2, check_exact=True)
+
 
 def test_compare_series_value_mismatch_string() -> None:
     srs1 = pl.Series(["hello", "no"])