[output] Skip the power limit setters when they match the defaults (#19225)

esphome/components/output/__init__.py

@@ -53,12 +53,17 @@ async def setup_output_platform_(obj, config):
     if CONF_POWER_SUPPLY in config:
         power_supply_ = await cg.get_variable(config[CONF_POWER_SUPPLY])
         cg.add(obj.set_power_supply(power_supply_))
-    if CONF_MAX_POWER in config:
+    # The C++ initializers are max_power 1.0 and min_power 0.0; skip the setter when
+    # the config matches them. The define stays whenever the key is present because
+    # platforms such as ac_dimmer read the scaling fields directly.
+    if (max_power := config.get(CONF_MAX_POWER)) is not None:
         cg.add_define("USE_OUTPUT_FLOAT_POWER_SCALING")
-        cg.add(obj.set_max_power(config[CONF_MAX_POWER]))
-    if CONF_MIN_POWER in config:
+        if max_power != 1.0:
+            cg.add(obj.set_max_power(max_power))
+    if (min_power := config.get(CONF_MIN_POWER)) is not None:
         cg.add_define("USE_OUTPUT_FLOAT_POWER_SCALING")
-        cg.add(obj.set_min_power(config[CONF_MIN_POWER]))
+        if min_power != 0.0:
+            cg.add(obj.set_min_power(min_power))
     # Only emit when zero_means_zero is actually enabled. The schema defaults to False
     # so this key is always present; emitting unconditionally would force
     # USE_OUTPUT_FLOAT_POWER_SCALING on for every output, defeating the gate.

esphome/components/output/float_output.h

@@ -123,6 +123,7 @@ class FloatOutput : public BinaryOutput {
   virtual void write_state(float state) = 0;
 
 #ifdef USE_OUTPUT_FLOAT_POWER_SCALING
+  // Codegen skips the setters for these values; keep in sync with output/__init__.py
   float max_power_{1.0f};
   float min_power_{0.0f};
   bool zero_means_zero_{false};

tests/component_tests/output/config/ac_dimmer_min_power_zero.yaml

@@ -0,0 +1,13 @@
+---
+esphome:
+  name: test
+
+esp32:
+  board: esp32dev
+
+output:
+  - platform: ac_dimmer
+    id: dimmer
+    gate_pin: GPIO4
+    zero_cross_pin: GPIO5
+    min_power: 0%

tests/component_tests/output/config/power_limits.yaml

@@ -0,0 +1,18 @@
+---
+esphome:
+  name: test
+
+esp32:
+  board: esp32dev
+
+output:
+  - platform: ledc
+    id: default_power
+    pin: GPIO4
+    max_power: 100%
+    min_power: 0%
+  - platform: ledc
+    id: custom_power
+    pin: GPIO5
+    max_power: 90%
+    min_power: 1%

tests/component_tests/output/test_output.py

@@ -0,0 +1,31 @@
+"""Tests for the output platform codegen."""
+
+from collections.abc import Callable
+from pathlib import Path
+
+from esphome.core import CORE
+
+
+def test_default_power_limits_are_not_emitted(
+    generate_main: Callable[[str | Path], str],
+    component_config_path: Callable[[str], Path],
+) -> None:
+    """max_power 100% and min_power 0% already live in the C++ initializers."""
+    main_cpp = generate_main(component_config_path("power_limits.yaml"))
+
+    assert "default_power->set_max_power(" not in main_cpp
+    assert "default_power->set_min_power(" not in main_cpp
+    assert "custom_power->set_max_power(0.9f);" in main_cpp
+    assert "custom_power->set_min_power(0.01f);" in main_cpp
+    assert "USE_OUTPUT_FLOAT_POWER_SCALING" in {d.name for d in CORE.defines}
+
+
+def test_default_min_power_keeps_scaling_fields(
+    generate_main: Callable[[str | Path], str],
+    component_config_path: Callable[[str], Path],
+) -> None:
+    """ac_dimmer reads min_power_ directly, so the define must stay on for min_power 0%."""
+    main_cpp = generate_main(component_config_path("ac_dimmer_min_power_zero.yaml"))
+
+    assert "dimmer->set_min_power(" not in main_cpp
+    assert "USE_OUTPUT_FLOAT_POWER_SCALING" in {d.name for d in CORE.defines}

tests/components/ac_dimmer/common.yaml

@@ -4,3 +4,4 @@ output:
     gate_pin: ${gate_pin}
     zero_cross_pin: ${zero_cross_pin}
     zero_cross_interrupt_type: ANY
+    min_power: 0%