Changed default behavior to True to avoid breaking change.

crates/polars-sql/src/functions.rs

@@ -987,7 +987,7 @@ impl SQLFunctionVisitor<'_> {
             // Array functions
             // ----
             ArrayContains => self.visit_binary::<Expr>(|e, s| e.list().contains(s)),
-            ArrayGet => self.visit_binary(|e, i| e.list().get(i, false)),
+            ArrayGet => self.visit_binary(|e, i| e.list().get(i, true)),
             ArrayLength => self.visit_unary(|e| e.list().len()),
             ArrayMax => self.visit_unary(|e| e.list().max()),
             ArrayMean => self.visit_unary(|e| e.list().mean()),

py-polars/polars/expr/list.py

@@ -509,7 +509,7 @@ def get(
         self,
         index: int | Expr | str,
         *,
-        null_on_oob: bool = False,
+        null_on_oob: bool = True,
     ) -> Expr:
         """
         Get the value by index in the sublists.
@@ -530,7 +530,7 @@ def get(
         Examples
         --------
         >>> df = pl.DataFrame({"a": [[3, 2, 1], [], [1, 2]]})
-        >>> df.with_columns(get=pl.col("a").list.get(0, null_on_oob=True))
+        >>> df.with_columns(get=pl.col("a").list.get(0))
         shape: (3, 2)
         ┌───────────┬──────┐
         │ a         ┆ get  │
@@ -650,7 +650,7 @@ def first(self) -> Expr:
         │ [1, 2]    ┆ 1     │
         └───────────┴───────┘
         """
-        return self.get(0, null_on_oob=True)
+        return self.get(0)
 
     def last(self) -> Expr:
         """
@@ -671,7 +671,7 @@ def last(self) -> Expr:
         │ [1, 2]    ┆ 2    │
         └───────────┴──────┘
         """
-        return self.get(-1, null_on_oob=True)
+        return self.get(-1)
 
     def contains(
         self, item: float | str | bool | int | date | datetime | time | IntoExprColumn

py-polars/tests/unit/namespaces/list/test_list.py

@@ -11,7 +11,7 @@
 
 def test_list_arr_get() -> None:
     a = pl.Series("a", [[1, 2, 3], [4, 5], [6, 7, 8, 9]])
-    out = a.list.get(0)
+    out = a.list.get(0, null_on_oob=False)
     expected = pl.Series("a", [1, 4, 6])
     assert_series_equal(out, expected)
     out = a.list[0]
@@ -22,7 +22,7 @@ def test_list_arr_get() -> None:
     out = pl.select(pl.lit(a).list.first()).to_series()
     assert_series_equal(out, expected)
 
-    out = a.list.get(-1)
+    out = a.list.get(-1, null_on_oob=False)
     expected = pl.Series("a", [3, 5, 9])
     assert_series_equal(out, expected)
     out = a.list.last()
@@ -31,30 +31,35 @@ def test_list_arr_get() -> None:
     assert_series_equal(out, expected)
 
     with pytest.raises(pl.ComputeError, match="get index is out of bounds"):
-        a.list.get(3)
+        a.list.get(3, null_on_oob=False)
 
     # Null index.
-    out_df = a.to_frame().select(pl.col.a.list.get(pl.lit(None)))
+    out_df = a.to_frame().select(pl.col.a.list.get(pl.lit(None), null_on_oob=False))
     expected_df = pl.Series("a", [None, None, None], dtype=pl.Int64).to_frame()
     assert_frame_equal(out_df, expected_df)
 
     a = pl.Series("a", [[1, 2, 3], [4, 5], [6, 7, 8, 9]])
 
     with pytest.raises(pl.ComputeError, match="get index is out of bounds"):
-        a.list.get(-3)
+        a.list.get(-3, null_on_oob=False)
 
     with pytest.raises(pl.ComputeError, match="get index is out of bounds"):
         pl.DataFrame(
             {"a": [[1], [2], [3], [4, 5, 6], [7, 8, 9], [None, 11]]}
         ).with_columns(
-            [pl.col("a").list.get(i).alias(f"get_{i}") for i in range(4)]
-        ).to_dict(as_series=False)
+            [
+                pl.col("a").list.get(i, null_on_oob=False).alias(f"get_{i}")
+                for i in range(4)
+            ]
+        )
 
     # get by indexes where some are out of bounds
     df = pl.DataFrame({"cars": [[1, 2, 3], [2, 3], [4], []], "indexes": [-2, 1, -3, 0]})
 
     with pytest.raises(pl.ComputeError, match="get index is out of bounds"):
-        df.select([pl.col("cars").list.get("indexes")]).to_dict(as_series=False)
+        df.select([pl.col("cars").list.get("indexes", null_on_oob=False)]).to_dict(
+            as_series=False
+        )
 
     # exact on oob boundary
     df = pl.DataFrame(
@@ -65,15 +70,15 @@ def test_list_arr_get() -> None:
     )
 
     with pytest.raises(pl.ComputeError, match="get index is out of bounds"):
-        df.select(pl.col("lists").list.get(3)).to_dict(as_series=False)
+        df.select(pl.col("lists").list.get(3, null_on_oob=False))
 
     with pytest.raises(pl.ComputeError, match="get index is out of bounds"):
-        df.select(pl.col("lists").list.get(pl.col("index"))).to_dict(as_series=False)
+        df.select(pl.col("lists").list.get(pl.col("index"), null_on_oob=False))
 
 
 def test_list_arr_get_null_on_oob() -> None:
     a = pl.Series("a", [[1, 2, 3], [4, 5], [6, 7, 8, 9]])
-    out = a.list.first()
+    out = a.list.get(0, null_on_oob=True)
     expected = pl.Series("a", [1, 4, 6])
     assert_series_equal(out, expected)
     out = a.list[0]