From 5e4a551a77627d3b66f4d331b2de19b7ec8b719f Mon Sep 17 00:00:00 2001
From: "J. Nick Koston" <nick@home-assistant.io>
Date: Sun, 26 Oct 2025 09:32:43 -0700
Subject: [PATCH] over engineered

---
 esphome/cpp_generator.py                |  7 +++----
 tests/component_tests/text/test_text.py |  2 +-
 tests/unit_tests/test_cpp_generator.py  | 18 ++++++++----------
 3 files changed, 12 insertions(+), 15 deletions(-)

diff --git a/esphome/cpp_generator.py b/esphome/cpp_generator.py
index 4e286dfa2c..a2da424e5a 100644
--- a/esphome/cpp_generator.py
+++ b/esphome/cpp_generator.py
@@ -198,10 +198,9 @@ class LambdaExpression(Expression):
         self.return_type = safe_exp(return_type) if return_type is not None else None
 
     def __str__(self):
-        # Unary + converts stateless lambda to function pointer
-        # This allows implicit conversion to void (*)() or bool (*)()
-        prefix = "+" if self.capture == "" else ""
-        cpp = f"{prefix}[{self.capture}]({self.parameters})"
+        # Stateless lambdas (empty capture) implicitly convert to function pointers
+        # when assigned to function pointer types - no unary + needed
+        cpp = f"[{self.capture}]({self.parameters})"
         if self.return_type is not None:
             cpp += f" -> {self.return_type}"
         cpp += " {\n"
diff --git a/tests/component_tests/text/test_text.py b/tests/component_tests/text/test_text.py
index 6eec86de9f..99ddd78ee7 100644
--- a/tests/component_tests/text/test_text.py
+++ b/tests/component_tests/text/test_text.py
@@ -66,5 +66,5 @@ def test_text_config_lamda_is_set(generate_main):
     main_cpp = generate_main("tests/component_tests/text/test_text.yaml")
 
     # Then
-    assert "it_4->set_template(+[]() -> esphome::optional<std::string> {" in main_cpp
+    assert "it_4->set_template([]() -> esphome::optional<std::string> {" in main_cpp
     assert 'return std::string{"Hello"};' in main_cpp
diff --git a/tests/unit_tests/test_cpp_generator.py b/tests/unit_tests/test_cpp_generator.py
index f42ad180c7..2c9f760c8e 100644
--- a/tests/unit_tests/test_cpp_generator.py
+++ b/tests/unit_tests/test_cpp_generator.py
@@ -174,7 +174,7 @@ class TestLambdaExpression:
         )
 
     def test_str__stateless_no_return(self):
-        """Test stateless lambda (empty capture) gets unary + prefix"""
+        """Test stateless lambda (empty capture) generates correctly"""
         target = cg.LambdaExpression(
             ('ESP_LOGD("main", "Test message");',),
             (),  # No parameters
@@ -183,10 +183,10 @@ class TestLambdaExpression:
 
         actual = str(target)
 
-        assert actual == ('+[]() {\n  ESP_LOGD("main", "Test message");\n}')
+        assert actual == ('[]() {\n  ESP_LOGD("main", "Test message");\n}')
 
     def test_str__stateless_with_return(self):
-        """Test stateless lambda with return type gets unary + prefix"""
+        """Test stateless lambda with return type generates correctly"""
         target = cg.LambdaExpression(
             ("return global_value > 0;",),
             (),  # No parameters
@@ -196,10 +196,10 @@ class TestLambdaExpression:
 
         actual = str(target)
 
-        assert actual == ("+[]() -> bool {\n  return global_value > 0;\n}")
+        assert actual == ("[]() -> bool {\n  return global_value > 0;\n}")
 
     def test_str__stateless_with_params(self):
-        """Test stateless lambda with parameters gets unary + prefix"""
+        """Test stateless lambda with parameters generates correctly"""
         target = cg.LambdaExpression(
             ("return foo + bar;",),
             ((int, "foo"), (float, "bar")),
@@ -210,11 +210,11 @@ class TestLambdaExpression:
         actual = str(target)
 
         assert actual == (
-            "+[](int32_t foo, float bar) -> float {\n  return foo + bar;\n}"
+            "[](int32_t foo, float bar) -> float {\n  return foo + bar;\n}"
         )
 
-    def test_str__with_capture_no_prefix(self):
-        """Test lambda with capture (not stateless) does NOT get + prefix"""
+    def test_str__with_capture(self):
+        """Test lambda with capture generates correctly"""
         target = cg.LambdaExpression(
             ("return captured_var + x;",),
             ((int, "x"),),
@@ -224,11 +224,9 @@ class TestLambdaExpression:
 
         actual = str(target)
 
-        # Should NOT have + prefix
         assert actual == (
             "[captured_var](int32_t x) -> int32_t {\n  return captured_var + x;\n}"
         )
-        assert not actual.startswith("+")
 
 
 class TestLiterals: