[core] Use placement new allocation for Pvariables (#15079)

Co-authored-by: J. Nick Koston <nick@home-assistant.io>
Co-authored-by: J. Nick Koston <nick@koston.org>

tests/component_tests/binary_sensor/test_binary_sensor.py

@@ -15,7 +15,7 @@ def test_binary_sensor_is_setup(generate_main):
     )
 
     # Then
-    assert "new gpio::GPIOBinarySensor();" in main_cpp
+    assert "static gpio::GPIOBinarySensor *const" in main_cpp
     assert "App.register_binary_sensor" in main_cpp
 
 

tests/component_tests/button/test_button.py

@@ -13,7 +13,8 @@ def test_button_is_setup(generate_main):
     main_cpp = generate_main("tests/component_tests/button/test_button.yaml")
 
     # Then
-    assert "new wake_on_lan::WakeOnLanButton();" in main_cpp
+    assert "static wake_on_lan::WakeOnLanButton *const" in main_cpp
+    assert ") wake_on_lan::WakeOnLanButton();" in main_cpp
     assert "App.register_button" in main_cpp
     assert "App.register_component" in main_cpp
 

tests/component_tests/conftest.py

@@ -134,7 +134,7 @@ def generate_main() -> Generator[Callable[[str | Path], str]]:
         CORE.config_path = Path(path)
         CORE.config = read_config({})
         generate_cpp_contents(CORE.config)
-        return CORE.cpp_main_section
+        return CORE.cpp_global_section + CORE.cpp_main_section
 
     yield generator
 

tests/component_tests/deep_sleep/test_deep_sleep.py

@@ -7,7 +7,11 @@ def test_deep_sleep_setup(generate_main):
     """
     main_cpp = generate_main("tests/component_tests/deep_sleep/test_deep_sleep1.yaml")
 
-    assert "deepsleep = new deep_sleep::DeepSleepComponent();" in main_cpp
+    assert (
+        "static deep_sleep::DeepSleepComponent *const deepsleep = reinterpret_cast<deep_sleep::DeepSleepComponent *>(deepsleep__pstorage);"
+        in main_cpp
+    )
+    assert "new(deepsleep) deep_sleep::DeepSleepComponent();" in main_cpp
     assert "App.register_component_(deepsleep);" in main_cpp
 
 

tests/component_tests/globals/config/globals_test.yaml

@@ -0,0 +1,16 @@
+esphome:
+  name: test
+
+esp32:
+  board: esp32dev
+
+globals:
+  - id: my_global_int
+    type: int
+    initial_value: "42"
+  - id: my_global_float
+    type: float
+    initial_value: "1.5"
+  - id: my_global_bool
+    type: bool
+    initial_value: "true"

tests/component_tests/globals/test_globals.py

@@ -0,0 +1,27 @@
+"""Tests for the globals component."""
+
+from __future__ import annotations
+
+from collections.abc import Callable
+from pathlib import Path
+
+
+def test_globals_placement_new_with_template_args(
+    generate_main: Callable[[str | Path], str],
+    component_config_path: Callable[[str], Path],
+) -> None:
+    """Test that globals uses placement new with template arguments preserved."""
+    main_cpp = generate_main(component_config_path("globals_test.yaml"))
+
+    # Globals uses Pvariable with Type.new(template_args, initial_value)
+    # which exercises the template_args preservation in placement new.
+    assert "static globals::GlobalsComponent<int> *const my_global_int" in main_cpp
+    assert "sizeof(globals::GlobalsComponent<int>)" in main_cpp
+    assert "new(my_global_int) globals::GlobalsComponent<int>" in main_cpp
+
+    # Verify initial value is passed as constructor arg
+    assert "42" in main_cpp
+
+    # Check other globals are also generated
+    assert "sizeof(globals::GlobalsComponent<float>)" in main_cpp
+    assert "sizeof(globals::GlobalsComponent<bool>)" in main_cpp

tests/component_tests/gpio/test_gpio_binary_sensor.py

@@ -16,7 +16,8 @@ def test_gpio_binary_sensor_basic_setup(
     """
     main_cpp = generate_main("tests/component_tests/gpio/test_gpio_binary_sensor.yaml")
 
-    assert "new gpio::GPIOBinarySensor();" in main_cpp
+    assert "static gpio::GPIOBinarySensor *const" in main_cpp
+    assert ") gpio::GPIOBinarySensor();" in main_cpp
     assert "App.register_binary_sensor" in main_cpp
     # set_use_interrupt(true) should NOT be generated (uses C++ default)
     assert "bs_gpio->set_use_interrupt(true);" not in main_cpp

tests/component_tests/image/test_init.py

@@ -242,7 +242,15 @@ def test_image_generation(
     main_cpp = generate_main(component_config_path("image_test.yaml"))
     assert "uint8_t_id[] PROGMEM = {0x24, 0x21, 0x24, 0x21" in main_cpp
     assert (
-        "cat_img = new image::Image(uint8_t_id, 32, 24, image::IMAGE_TYPE_RGB565, image::TRANSPARENCY_OPAQUE);"
+        "alignas(image::Image) static unsigned char cat_img__pstorage[sizeof(image::Image)];"
+        in main_cpp
+    )
+    assert (
+        "static image::Image *const cat_img = reinterpret_cast<image::Image *>(cat_img__pstorage);"
+        in main_cpp
+    )
+    assert (
+        "new(cat_img) image::Image(uint8_t_id, 32, 24, image::IMAGE_TYPE_RGB565, image::TRANSPARENCY_OPAQUE);"
         in main_cpp
     )
 

tests/component_tests/logger/test_logger.py

@@ -22,6 +22,10 @@ def test_logger_pre_setup_before_other_components(generate_main):
 
     # Find all "new " allocations (component creation)
     new_allocations = list(re.finditer(r"\bnew [\w:]+", main_cpp))
+    # Find all "new(" allocations (component creation) and combine them
+    new_allocations.extend(re.finditer(r"\bnew\([^)]+\) [\w:]+", main_cpp))
+    # Sort allocations by position in the file
+    new_allocations.sort(key=lambda m: m.start())
     assert len(new_allocations) > 0, "No component allocations found"
 
     # Separate logger and non-logger allocations

tests/component_tests/mipi_dsi/test_mipi_dsi_config.py

@@ -119,7 +119,15 @@ def test_code_generation(
 
     main_cpp = generate_main(component_fixture_path("mipi_dsi.yaml"))
     assert (
-        "p4_nano = new mipi_dsi::MIPI_DSI(800, 1280, display::COLOR_BITNESS_565, 16);"
+        "alignas(mipi_dsi::MIPI_DSI) static unsigned char p4_nano__pstorage[sizeof(mipi_dsi::MIPI_DSI)];"
+        in main_cpp
+    )
+    assert (
+        "static mipi_dsi::MIPI_DSI *const p4_nano = reinterpret_cast<mipi_dsi::MIPI_DSI *>(p4_nano__pstorage);"
+        in main_cpp
+    )
+    assert (
+        "new(p4_nano) mipi_dsi::MIPI_DSI(800, 1280, display::COLOR_BITNESS_565, 16);"
         in main_cpp
     )
     assert "set_init_sequence({224, 1, 0, 225, 1, 147, 226, 1," in main_cpp

tests/component_tests/status_led/config/status_led_test.yaml

@@ -0,0 +1,8 @@
+esphome:
+  name: test
+
+esp32:
+  board: esp32dev
+
+status_led:
+  pin: GPIO2

tests/component_tests/status_led/test_status_led.py

@@ -0,0 +1,23 @@
+"""Tests for status_led."""
+
+from __future__ import annotations
+
+from collections.abc import Callable
+from pathlib import Path
+
+
+def test_status_led_generation(
+    generate_main: Callable[[str | Path], str],
+    component_config_path: Callable[[str], Path],
+) -> None:
+    """Test status_led generation."""
+    main_cpp = generate_main(component_config_path("status_led_test.yaml"))
+    assert (
+        "alignas(status_led::StatusLED) static unsigned char status_led_statusled_id__pstorage[sizeof(status_led::StatusLED)];"
+        in main_cpp
+    )
+    assert (
+        "static status_led::StatusLED *const status_led_statusled_id = reinterpret_cast<status_led::StatusLED *>(status_led_statusled_id__pstorage);"
+        in main_cpp
+    )
+    assert "new(status_led_statusled_id) status_led::StatusLED(" in main_cpp

tests/component_tests/text/test_text.py

@@ -13,7 +13,8 @@ def test_text_is_setup(generate_main):
     main_cpp = generate_main("tests/component_tests/text/test_text.yaml")
 
     # Then
-    assert "new template_::TemplateText();" in main_cpp
+    assert "static template_::TemplateText *const" in main_cpp
+    assert ") template_::TemplateText();" in main_cpp
     assert "App.register_text" in main_cpp
 
 

tests/component_tests/text_sensor/test_text_sensor.py

@@ -13,7 +13,8 @@ def test_text_sensor_is_setup(generate_main):
     main_cpp = generate_main("tests/component_tests/text_sensor/test_text_sensor.yaml")
 
     # Then
-    assert "new template_::TemplateTextSensor();" in main_cpp
+    assert "static template_::TemplateTextSensor *const" in main_cpp
+    assert ") template_::TemplateTextSensor();" in main_cpp
     assert "App.register_text_sensor" in main_cpp