[output] Add ApplyFloatOutput and ApplyBinaryOutput

esphome/components/output/__init__.py

@@ -13,7 +13,9 @@ from esphome.const import (
     CONF_MIN_POWER,
     CONF_POWER_SUPPLY,
 )
-from esphome.core import CORE
+from esphome.core import CORE, ID
+from esphome.core.entity_helpers import ApplyEntity, SubEntities
+from esphome.cpp_generator import MockObj, SafeExpType
 from esphome.types import ConfigType
 
 CODEOWNERS = ["@esphome/core"]
@@ -54,6 +56,8 @@ BinaryOutput = output_ns.class_("BinaryOutput")
 BinaryOutputPtr = BinaryOutput.operator("ptr")
 FloatOutput = output_ns.class_("FloatOutput", BinaryOutput)
 FloatOutputPtr = FloatOutput.operator("ptr")
+ApplyBinaryOutput = output_ns.class_("ApplyBinaryOutput", BinaryOutput)
+ApplyFloatOutput = output_ns.class_("ApplyFloatOutput", FloatOutput)
 
 
 async def setup_output_platform_(obj, config):
@@ -84,6 +88,34 @@ async def register_output(var, config):
     await setup_output_platform_(var, config)
 
 
+async def new_output(config: ConfigType, *args: SafeExpType) -> MockObj:
+    var = cg.new_Pvariable(config[CONF_ID], *args)
+    await register_output(var, config)
+    return var
+
+
+BINARY_APPLY_ENTITY = ApplyEntity(
+    ApplyBinaryOutput, ((BinaryOutputPtr, "entity"), (cg.bool_, "state"))
+)
+FLOAT_APPLY_ENTITY = ApplyEntity(
+    ApplyFloatOutput, ((FloatOutputPtr, "entity"), (cg.float_, "state"))
+)
+
+
+def sub_binary_outputs(
+    config: ConfigType, *, parent: MockObj | ID | None = None
+) -> SubEntities:
+    """Return a SubEntities bound to new_output; ``apply`` statements can use ``entity`` and ``state``."""
+    return SubEntities(new_output, config, parent, BINARY_APPLY_ENTITY)
+
+
+def sub_float_outputs(
+    config: ConfigType, *, parent: MockObj | ID | None = None
+) -> SubEntities:
+    """Return a SubEntities bound to new_output; ``apply`` gets the scaled level as ``state``."""
+    return SubEntities(new_output, config, parent, FLOAT_APPLY_ENTITY)
+
+
 BINARY_OUTPUT_ACTION_SCHEMA = maybe_simple_id(
     {
         cv.Required(CONF_ID): cv.use_id(BinaryOutput),

esphome/components/output/binary_output.h

@@ -68,4 +68,14 @@ class BinaryOutput {
 #endif
 };
 
+/// Calls the codegen-generated Fn(this, state) on a state write; the hub is baked into Fn.
+template<auto Fn> class ApplyBinaryOutput final : public BinaryOutput {
+ public:
+  // Not "= default": placement new would zero-fill .bss that is already zero.
+  ApplyBinaryOutput() {}
+
+ protected:
+  void write_state(bool state) override { Fn(this, state); }
+};
+
 }  // namespace esphome::output

esphome/components/output/float_output.h

@@ -130,4 +130,14 @@ class FloatOutput : public BinaryOutput {
 #endif
 };
 
+/// Calls the codegen-generated Fn(this, state) with the scaled, inverted level; the hub is baked into Fn.
+template<auto Fn> class ApplyFloatOutput final : public FloatOutput {
+ public:
+  // Not "= default": placement new would zero-fill .bss that is already zero.
+  ApplyFloatOutput() {}
+
+ protected:
+  void write_state(float state) override { Fn(this, state); }
+};
+
 }  // namespace esphome::output

tests/components/output/apply_output_test.cpp

@@ -0,0 +1,67 @@
+#include <gtest/gtest.h>
+
+#include <vector>
+
+#include "esphome/components/output/binary_output.h"
+#include "esphome/components/output/float_output.h"
+
+namespace esphome::output::testing {
+
+static void *last_output = nullptr;    // NOLINT(cppcoreguidelines-avoid-non-const-global-variables)
+static std::vector<bool> bool_writes;  // NOLINT(cppcoreguidelines-avoid-non-const-global-variables)
+static std::vector<float> levels;      // NOLINT(cppcoreguidelines-avoid-non-const-global-variables)
+
+static void on_binary_write(BinaryOutput *output, bool state) {
+  last_output = output;
+  bool_writes.push_back(state);
+}
+
+static void on_float_write(FloatOutput *output, float state) {
+  last_output = output;
+  levels.push_back(state);
+}
+
+TEST(ApplyBinaryOutput, WriteRunsTheFunctionWithTheState) {
+  last_output = nullptr;
+  bool_writes.clear();
+  ApplyBinaryOutput<on_binary_write> out;
+  out.turn_on();
+  out.turn_off();
+  EXPECT_EQ(bool_writes, (std::vector<bool>{true, false}));
+  EXPECT_EQ(last_output, &out);
+}
+
+TEST(ApplyBinaryOutput, InversionIsAppliedBeforeTheFunction) {
+  bool_writes.clear();
+  ApplyBinaryOutput<on_binary_write> out;
+  out.set_inverted(true);
+  out.turn_on();
+  EXPECT_EQ(bool_writes, (std::vector<bool>{false}));
+}
+
+TEST(ApplyFloatOutput, WriteRunsTheFunctionWithTheLevel) {
+  last_output = nullptr;
+  levels.clear();
+  ApplyFloatOutput<on_float_write> out;
+  out.set_level(0.25f);
+  out.turn_on();
+  out.turn_off();
+  EXPECT_EQ(levels, (std::vector<float>{0.25f, 1.0f, 0.0f}));
+  EXPECT_EQ(last_output, &out);
+}
+
+TEST(ApplyFloatOutput, InversionAndClampAreAppliedBeforeTheFunction) {
+  levels.clear();
+  ApplyFloatOutput<on_float_write> out;
+  out.set_inverted(true);
+  out.set_level(0.25f);
+  out.set_level(2.0f);
+  EXPECT_EQ(levels, (std::vector<float>{0.75f, 0.0f}));
+}
+
+TEST(ApplyOutput, HoldsNoMoreThanTheBase) {
+  EXPECT_EQ(sizeof(ApplyBinaryOutput<on_binary_write>), sizeof(BinaryOutput));
+  EXPECT_EQ(sizeof(ApplyFloatOutput<on_float_write>), sizeof(FloatOutput));
+}
+
+}  // namespace esphome::output::testing

tests/unit_tests/core/test_entity_helpers.py

@@ -8,7 +8,7 @@ from typing import Any
 import pytest
 
 import esphome.codegen as cg
-from esphome.components import button, number, select, switch
+from esphome.components import button, number, output, select, switch
 from esphome.config_validation import Invalid
 from esphome.const import (
     CONF_DEVICE_CLASS,
@@ -1565,6 +1565,18 @@ async def test_sub_entities_apply_needs_parent(
             "select::Select * entity, size_t index",
             "entity->publish_state(index);",
         ),
+        (
+            output.sub_binary_outputs,
+            output.ApplyBinaryOutput,
+            "output::BinaryOutput * entity, bool state",
+            None,
+        ),
+        (
+            output.sub_float_outputs,
+            output.ApplyFloatOutput,
+            "output::FloatOutput * entity, float state",
+            None,
+        ),
     ],
 )
 def test_domain_apply_entities(