Add apply to make macros/callables useful in filters and tests

homeassistant/helpers/template.py

@@ -2019,6 +2019,11 @@ def add(value, amount, default=_SENTINEL):
         return default
 
 
+def apply(value, fn, *args, **kwargs):
+    """Call the given callable with the provided arguments and keyword arguments."""
+    return fn(value, *args, **kwargs)
+
+
 def logarithm(value, base=math.e, default=_SENTINEL):
     """Filter and function to get logarithm of the value with a specific base."""
     try:
@@ -3110,6 +3115,7 @@ def __init__(
 
         self.filters["acos"] = arc_cosine
         self.filters["add"] = add
+        self.filters["apply"] = apply
         self.filters["as_datetime"] = as_datetime
         self.filters["as_local"] = dt_util.as_local
         self.filters["as_timedelta"] = as_timedelta
@@ -3169,6 +3175,7 @@ def __init__(
         self.filters["unpack"] = struct_unpack
         self.filters["version"] = version
 
+        self.tests["apply"] = apply
         self.tests["contains"] = contains
         self.tests["datetime"] = _is_datetime
         self.tests["is_number"] = is_number

tests/helpers/test_template.py

@@ -772,6 +772,62 @@ def test_add(hass: HomeAssistant) -> None:
     assert render(hass, "{{ 'no_number' | add(10, default=1) }}") == 1
 
 
+def test_apply(hass: HomeAssistant) -> None:
+    """Test apply."""
+    assert template.Template(
+        """
+        {%- macro add_foo(arg) -%}
+        {{arg}}foo
+        {%- endmacro -%}
+        {{ ["a", "b", "c"] | map('apply', add_foo) | list }}
+        """,
+        hass,
+    ).async_render() == ["afoo", "bfoo", "cfoo"]
+
+    assert template.Template(
+        """
+        {{ ['1', '2', '3', '4', '5'] | map('apply', int) | list }}
+        """,
+        hass,
+    ).async_render() == [1, 2, 3, 4, 5]
+
+
+def test_apply_macro_with_arguments(hass: HomeAssistant) -> None:
+    """Test apply macro with positional, named, and mixed arguments."""
+    # Test macro with positional arguments
+    assert template.Template(
+        """
+        {%- macro greet(name, greeting) -%}
+        {{ greeting }}, {{ name }}!
+        {%- endmacro %}
+        {{ ["Alice", "Bob"] | map('apply', greet, "Hello") | list }}
+        """,
+        hass,
+    ).async_render() == ["Hello, Alice!", "Hello, Bob!"]
+
+    # Test macro with named arguments
+    assert template.Template(
+        """
+        {%- macro greet(name, greeting="Hi") -%}
+        {{ greeting }}, {{ name }}!
+        {%- endmacro %}
+        {{ ["Alice", "Bob"] | map('apply', greet, greeting="Hello") | list }}
+        """,
+        hass,
+    ).async_render() == ["Hello, Alice!", "Hello, Bob!"]
+
+    # Test macro with mixed positional and named arguments
+    assert template.Template(
+        """
+        {%- macro greet(name, separator, greeting="Hi") -%}
+        {{ greeting }}{{separator}} {{ name }}!
+        {%- endmacro %}
+        {{ ["Alice", "Bob"] | map('apply', greet, "," , greeting="Hey") | list }}
+        """,
+        hass,
+    ).async_render() == ["Hey, Alice!", "Hey, Bob!"]
+
+
 def test_logarithm(hass: HomeAssistant) -> None:
     """Test logarithm."""
     tests = [