feat: add duckdb .str.to_datetime (#1916)

feat: duckdb str to_datetime

Author: FBruzzesi

narwhals/_duckdb/expr_str.py

@@ -126,3 +126,16 @@ def replace(
     ) -> NoReturn:
         msg = "`replace` is currently not supported for DuckDB"
         raise NotImplementedError(msg)
+
+    def to_datetime(self: Self, format: str | None) -> DuckDBExpr:  # noqa: A002
+        if format is None:
+            msg = "Cannot infer format with DuckDB backend"
+            raise NotImplementedError(msg)
+
+        return self._compliant_expr._from_call(
+            lambda _input: FunctionExpression(
+                "strptime", _input, ConstantExpression(format)
+            ),
+            "to_datetime",
+            expr_kind=self._compliant_expr._expr_kind,
+        )

tests/expr_and_series/str/to_datetime_test.py

@@ -18,9 +18,7 @@
 data = {"a": ["2020-01-01T12:34:56"]}
 
 
-def test_to_datetime(constructor: Constructor, request: pytest.FixtureRequest) -> None:
-    if "duckdb" in str(constructor):
-        request.applymarker(pytest.mark.xfail)
+def test_to_datetime(constructor: Constructor) -> None:
     if "cudf" in str(constructor):
         expected = "2020-01-01T12:34:56.000000000"
     else: