Merge remote-tracking branch 'upstream/dev' into integration

esphome/components/esp32_improv/__init__.py

@@ -112,7 +112,7 @@ async def to_code(config):
 
     cg.add_define("USE_IMPROV")
 
-    await improv_base.setup_improv_core(var, config)
+    await improv_base.setup_improv_core(var, config, "esp32_improv")
 
     cg.add(var.set_identify_duration(config[CONF_IDENTIFY_DURATION]))
     cg.add(var.set_authorized_duration(config[CONF_AUTHORIZED_DURATION]))

esphome/components/esp32_improv/esp32_improv_component.cpp

@@ -389,11 +389,13 @@ void ESP32ImprovComponent::check_wifi_connection_() {
     std::string url_strings[3];
     size_t url_count = 0;
 
+#ifdef USE_ESP32_IMPROV_NEXT_URL
     // Add next_url if configured (should be first per Improv BLE spec)
     std::string next_url = this->get_formatted_next_url_();
     if (!next_url.empty()) {
       url_strings[url_count++] = std::move(next_url);
     }
+#endif
 
     // Add default URLs for backward compatibility
     url_strings[url_count++] = ESPHOME_MY_LINK;

esphome/components/improv_base/__init__.py

@@ -3,6 +3,8 @@ import re
 import esphome.codegen as cg
 import esphome.config_validation as cv
 from esphome.const import __version__
+from esphome.cpp_generator import MockObj
+from esphome.types import ConfigType
 
 CODEOWNERS = ["@esphome/core"]
 
@@ -35,7 +37,9 @@ def _process_next_url(url: str):
     return url
 
 
-async def setup_improv_core(var, config):
-    if CONF_NEXT_URL in config:
-        cg.add(var.set_next_url(_process_next_url(config[CONF_NEXT_URL])))
+async def setup_improv_core(var: MockObj, config: ConfigType, component: str):
+    if next_url := config.get(CONF_NEXT_URL):
+        cg.add(var.set_next_url(_process_next_url(next_url)))
+        cg.add_define(f"USE_{component.upper()}_NEXT_URL")
+
     cg.add_library("improv/Improv", "1.2.4")

esphome/components/improv_base/improv_base.cpp

@@ -2,10 +2,12 @@
 
 #include "esphome/components/network/util.h"
 #include "esphome/core/application.h"
+#include "esphome/core/defines.h"
 
 namespace esphome {
 namespace improv_base {
 
+#if defined(USE_ESP32_IMPROV_NEXT_URL) || defined(USE_IMPROV_SERIAL_NEXT_URL)
 static constexpr const char DEVICE_NAME_PLACEHOLDER[] = "{{device_name}}";
 static constexpr size_t DEVICE_NAME_PLACEHOLDER_LEN = sizeof(DEVICE_NAME_PLACEHOLDER) - 1;
 static constexpr const char IP_ADDRESS_PLACEHOLDER[] = "{{ip_address}}";
@@ -43,6 +45,7 @@ std::string ImprovBase::get_formatted_next_url_() {
 
   return formatted_url;
 }
+#endif
 
 }  // namespace improv_base
 }  // namespace esphome

esphome/components/improv_base/improv_base.h

@@ -1,17 +1,22 @@
 #pragma once
 
 #include <string>
+#include "esphome/core/defines.h"
 
 namespace esphome {
 namespace improv_base {
 
 class ImprovBase {
  public:
+#if defined(USE_ESP32_IMPROV_NEXT_URL) || defined(USE_IMPROV_SERIAL_NEXT_URL)
   void set_next_url(const std::string &next_url) { this->next_url_ = next_url; }
+#endif
 
  protected:
+#if defined(USE_ESP32_IMPROV_NEXT_URL) || defined(USE_IMPROV_SERIAL_NEXT_URL)
   std::string get_formatted_next_url_();
   std::string next_url_;
+#endif
 };
 
 }  // namespace improv_base

esphome/components/improv_serial/__init__.py

@@ -43,4 +43,4 @@ FINAL_VALIDATE_SCHEMA = validate_logger
 async def to_code(config):
     var = cg.new_Pvariable(config[CONF_ID])
     await cg.register_component(var, config)
-    await improv_base.setup_improv_core(var, config)
+    await improv_base.setup_improv_core(var, config, "improv_serial")

esphome/components/improv_serial/improv_serial_component.cpp

@@ -146,9 +146,11 @@ void ImprovSerialComponent::loop() {
 
 std::vector<uint8_t> ImprovSerialComponent::build_rpc_settings_response_(improv::Command command) {
   std::vector<std::string> urls;
+#ifdef USE_IMPROV_SERIAL_NEXT_URL
   if (!this->next_url_.empty()) {
     urls.push_back(this->get_formatted_next_url_());
   }
+#endif
 #ifdef USE_WEBSERVER
   for (auto &ip : wifi::global_wifi_component->wifi_sta_ip_addresses()) {
     if (ip.is_ip4()) {

esphome/components/text_sensor/filter.cpp

@@ -62,7 +62,8 @@ optional<std::string> AppendFilter::new_value(std::string value) { return value
 optional<std::string> PrependFilter::new_value(std::string value) { return this->prefix_ + value; }
 
 // Substitute
-SubstituteFilter::SubstituteFilter(std::initializer_list<Substitution> substitutions) : substitutions_(substitutions) {}
+SubstituteFilter::SubstituteFilter(const std::initializer_list<Substitution> &substitutions)
+    : substitutions_(substitutions) {}
 
 optional<std::string> SubstituteFilter::new_value(std::string value) {
   std::size_t pos;
@@ -74,7 +75,7 @@ optional<std::string> SubstituteFilter::new_value(std::string value) {
 }
 
 // Map
-MapFilter::MapFilter(std::initializer_list<Substitution> mappings) : mappings_(mappings) {}
+MapFilter::MapFilter(const std::initializer_list<Substitution> &mappings) : mappings_(mappings) {}
 
 optional<std::string> MapFilter::new_value(std::string value) {
   for (const auto &mapping : this->mappings_) {

esphome/components/text_sensor/filter.h

@@ -102,7 +102,7 @@ struct Substitution {
 /// A simple filter that replaces a substring with another substring
 class SubstituteFilter : public Filter {
  public:
-  explicit SubstituteFilter(std::initializer_list<Substitution> substitutions);
+  explicit SubstituteFilter(const std::initializer_list<Substitution> &substitutions);
   optional<std::string> new_value(std::string value) override;
 
  protected:
@@ -135,7 +135,7 @@ class SubstituteFilter : public Filter {
  */
 class MapFilter : public Filter {
  public:
-  explicit MapFilter(std::initializer_list<Substitution> mappings);
+  explicit MapFilter(const std::initializer_list<Substitution> &mappings);
   optional<std::string> new_value(std::string value) override;
 
  protected:

esphome/const.py

@@ -471,6 +471,7 @@ CONF_IMPORT_REACTIVE_ENERGY = "import_reactive_energy"
 CONF_INC_PIN = "inc_pin"
 CONF_INCLUDE_INTERNAL = "include_internal"
 CONF_INCLUDES = "includes"
+CONF_INCLUDES_C = "includes_c"
 CONF_INDEX = "index"
 CONF_INDOOR = "indoor"
 CONF_INFRARED = "infrared"

esphome/core/config.py

@@ -21,6 +21,7 @@ from esphome.const import (
     CONF_FRIENDLY_NAME,
     CONF_ID,
     CONF_INCLUDES,
+    CONF_INCLUDES_C,
     CONF_LIBRARIES,
     CONF_MIN_VERSION,
     CONF_NAME,
@@ -227,6 +228,7 @@ CONFIG_SCHEMA = cv.All(
                 }
             ),
             cv.Optional(CONF_INCLUDES, default=[]): cv.ensure_list(valid_include),
+            cv.Optional(CONF_INCLUDES_C, default=[]): cv.ensure_list(valid_include),
             cv.Optional(CONF_LIBRARIES, default=[]): cv.ensure_list(cv.string_strict),
             cv.Optional(CONF_NAME_ADD_MAC_SUFFIX, default=False): cv.boolean,
             cv.Optional(CONF_DEBUG_SCHEDULER, default=False): cv.boolean,
@@ -302,6 +304,17 @@ def _list_target_platforms():
     return target_platforms
 
 
+def _sort_includes_by_type(includes: list[str]) -> tuple[list[str], list[str]]:
+    system_includes = []
+    other_includes = []
+    for include in includes:
+        if include.startswith("<") and include.endswith(">"):
+            system_includes.append(include)
+        else:
+            other_includes.append(include)
+    return system_includes, other_includes
+
+
 def preload_core_config(config, result) -> str:
     with cv.prepend_path(CONF_ESPHOME):
         conf = PRELOAD_CONFIG_SCHEMA(config[CONF_ESPHOME])
@@ -339,7 +352,7 @@ def preload_core_config(config, result) -> str:
     return target_platforms[0]
 
 
-def include_file(path: Path, basename: Path):
+def include_file(path: Path, basename: Path, is_c_header: bool = False):
     parts = basename.parts
     dst = CORE.relative_src_path(*parts)
     copy_file_if_changed(path, dst)
@@ -347,7 +360,14 @@ def include_file(path: Path, basename: Path):
     ext = path.suffix
     if ext in [".h", ".hpp", ".tcc"]:
         # Header, add include statement
-        cg.add_global(cg.RawStatement(f'#include "{basename}"'))
+        if is_c_header:
+            # Wrap in extern "C" block for C headers
+            cg.add_global(
+                cg.RawStatement(f'extern "C" {{\n  #include "{basename}"\n}}')
+            )
+        else:
+            # Regular include
+            cg.add_global(cg.RawStatement(f'#include "{basename}"'))
 
 
 ARDUINO_GLUE_CODE = """\
@@ -377,7 +397,7 @@ async def add_arduino_global_workaround():
 
 
 @coroutine_with_priority(CoroPriority.FINAL)
-async def add_includes(includes: list[str]) -> None:
+async def add_includes(includes: list[str], is_c_header: bool = False) -> None:
     # Add includes at the very end, so that the included files can access global variables
     for include in includes:
         path = CORE.relative_config_path(include)
@@ -385,11 +405,11 @@ async def add_includes(includes: list[str]) -> None:
             # Directory, copy tree
             for p in walk_files(path):
                 basename = p.relative_to(path.parent)
-                include_file(p, basename)
+                include_file(p, basename, is_c_header)
         else:
             # Copy file
             basename = Path(path.name)
-            include_file(path, basename)
+            include_file(path, basename, is_c_header)
 
 
 @coroutine_with_priority(CoroPriority.FINAL)
@@ -494,19 +514,25 @@ async def to_code(config: ConfigType) -> None:
         CORE.add_job(add_arduino_global_workaround)
 
     if config[CONF_INCLUDES]:
-        # Get the <...> includes
-        system_includes = []
-        other_includes = []
-        for include in config[CONF_INCLUDES]:
-            if include.startswith("<") and include.endswith(">"):
-                system_includes.append(include)
-            else:
-                other_includes.append(include)
+        system_includes, other_includes = _sort_includes_by_type(config[CONF_INCLUDES])
         # <...> includes should be at the start
         for include in system_includes:
             cg.add_global(cg.RawStatement(f"#include {include}"), prepend=True)
         # Other includes should be at the end
-        CORE.add_job(add_includes, other_includes)
+        CORE.add_job(add_includes, other_includes, False)
+
+    if config[CONF_INCLUDES_C]:
+        system_includes, other_includes = _sort_includes_by_type(
+            config[CONF_INCLUDES_C]
+        )
+        # <...> includes should be at the start
+        for include in system_includes:
+            cg.add_global(
+                cg.RawStatement(f'extern "C" {{\n  #include {include}\n}}'),
+                prepend=True,
+            )
+        # Other includes should be at the end
+        CORE.add_job(add_includes, other_includes, True)
 
     if project_conf := config.get(CONF_PROJECT):
         cg.add_define("ESPHOME_PROJECT_NAME", project_conf[CONF_NAME])

esphome/core/defines.h

@@ -44,6 +44,7 @@
 #define USE_GRAPHICAL_DISPLAY_MENU
 #define USE_HOMEASSISTANT_TIME
 #define USE_HTTP_REQUEST_OTA_WATCHDOG_TIMEOUT 8000  // NOLINT
+#define USE_IMPROV_SERIAL_NEXT_URL
 #define USE_JSON
 #define USE_LIGHT
 #define USE_LOCK
@@ -186,6 +187,7 @@
 #define USE_ESP32_CAMERA_JPEG_ENCODER
 #define USE_I2C
 #define USE_IMPROV
+#define USE_ESP32_IMPROV_NEXT_URL
 #define USE_MICROPHONE
 #define USE_PSRAM
 #define USE_SOCKET_IMPL_BSD_SOCKETS

script/determine-jobs.py

@@ -57,6 +57,7 @@ from helpers import (
     get_component_from_path,
     get_component_test_files,
     get_components_from_integration_fixtures,
+    git_ls_files,
     parse_test_filename,
     root_path,
 )
@@ -162,6 +163,26 @@ def should_run_integration_tests(branch: str | None = None) -> bool:
     return False
 
 
+@cache
+def _is_clang_tidy_full_scan() -> bool:
+    """Check if clang-tidy configuration changed (requires full scan).
+
+    Returns:
+        True if full scan is needed (hash changed), False otherwise.
+    """
+    try:
+        result = subprocess.run(
+            [os.path.join(root_path, "script", "clang_tidy_hash.py"), "--check"],
+            capture_output=True,
+            check=False,
+        )
+        # Exit 0 means hash changed (full scan needed)
+        return result.returncode == 0
+    except Exception:
+        # If hash check fails, run full scan to be safe
+        return True
+
+
 def should_run_clang_tidy(branch: str | None = None) -> bool:
     """Determine if clang-tidy should run based on changed files.
 
@@ -198,17 +219,7 @@ def should_run_clang_tidy(branch: str | None = None) -> bool:
         True if clang-tidy should run, False otherwise.
     """
     # First check if clang-tidy configuration changed (full scan needed)
-    try:
-        result = subprocess.run(
-            [os.path.join(root_path, "script", "clang_tidy_hash.py"), "--check"],
-            capture_output=True,
-            check=False,
-        )
-        # Exit 0 means hash changed (full scan needed)
-        if result.returncode == 0:
-            return True
-    except Exception:
-        # If hash check fails, run clang-tidy to be safe
+    if _is_clang_tidy_full_scan():
         return True
 
     # Check if .clang-tidy.hash file itself was changed
@@ -586,13 +597,37 @@ def main() -> None:
     # Detect components for memory impact analysis (merged config)
     memory_impact = detect_memory_impact_config(args.branch)
 
+    # Determine clang-tidy mode based on actual files that will be checked
     if run_clang_tidy:
-        if changed_cpp_file_count < CLANG_TIDY_SPLIT_THRESHOLD:
-            clang_tidy_mode = "nosplit"
-        else:
+        is_full_scan = _is_clang_tidy_full_scan()
+
+        if is_full_scan:
+            # Full scan checks all files - always use split mode for efficiency
             clang_tidy_mode = "split"
+            files_to_check_count = -1  # Sentinel value for "all files"
+        else:
+            # Targeted scan - calculate actual files that will be checked
+            # This accounts for component dependencies, not just directly changed files
+            if changed_components:
+                # Count C++ files in all changed components (including dependencies)
+                all_cpp_files = list(git_ls_files(["*.cpp"]).keys())
+                component_set = set(changed_components)
+                files_to_check_count = sum(
+                    1
+                    for f in all_cpp_files
+                    if get_component_from_path(f) in component_set
+                )
+            else:
+                # If no components changed, use the simple count of changed C++ files
+                files_to_check_count = changed_cpp_file_count
+
+            if files_to_check_count < CLANG_TIDY_SPLIT_THRESHOLD:
+                clang_tidy_mode = "nosplit"
+            else:
+                clang_tidy_mode = "split"
     else:
         clang_tidy_mode = "disabled"
+        files_to_check_count = 0
 
     # Build output
     output: dict[str, Any] = {

script/test_build_components.py

@@ -966,11 +966,33 @@ def test_components(
     # Find all component tests
     all_tests = {}
     for pattern in component_patterns:
+        # Skip empty patterns (happens when components list is empty string)
+        if not pattern:
+            continue
         all_tests.update(find_component_tests(tests_dir, pattern, base_only))
 
+    # If no components found, build a reference configuration for baseline comparison
+    # Create a synthetic "empty" component test that will build just the base config
     if not all_tests:
         print(f"No components found matching: {component_patterns}")
-        return 1
+        print(
+            "Building reference configuration with no components for baseline comparison..."
+        )
+
+        # Create empty test files for each platform (or filtered platform)
+        reference_tests: list[Path] = []
+        for platform_name, base_file in platform_bases.items():
+            if platform_filter and not platform_name.startswith(platform_filter):
+                continue
+            # Create an empty test file named to match the platform
+            empty_test_file = build_dir / f"reference.{platform_name}.yaml"
+            empty_test_file.write_text(
+                "# Empty component test for baseline reference\n"
+            )
+            reference_tests.append(empty_test_file)
+
+        # Add to all_tests dict with component name "reference"
+        all_tests["reference"] = reference_tests
 
     print(f"Found {len(all_tests)} components to test")
 

tests/script/test_determine_jobs.py

@@ -71,6 +71,12 @@ def mock_changed_files() -> Generator[Mock, None, None]:
         yield mock
 
 
+@pytest.fixture(autouse=True)
+def clear_clang_tidy_cache() -> None:
+    """Clear the clang-tidy full scan cache before each test."""
+    determine_jobs._is_clang_tidy_full_scan.cache_clear()
+
+
 def test_main_all_tests_should_run(
     mock_should_run_integration_tests: Mock,
     mock_should_run_clang_tidy: Mock,
@@ -98,7 +104,10 @@ def test_main_all_tests_should_run(
     mock_subprocess_run.return_value = mock_result
 
     # Run main function with mocked argv
-    with patch("sys.argv", ["determine-jobs.py"]):
+    with (
+        patch("sys.argv", ["determine-jobs.py"]),
+        patch.object(determine_jobs, "_is_clang_tidy_full_scan", return_value=False),
+    ):
         determine_jobs.main()
 
     # Check output
@@ -224,7 +233,10 @@ def test_main_with_branch_argument(
     )
     mock_subprocess_run.return_value = mock_result
 
-    with patch("sys.argv", ["script.py", "-b", "main"]):
+    with (
+        patch("sys.argv", ["script.py", "-b", "main"]),
+        patch.object(determine_jobs, "_is_clang_tidy_full_scan", return_value=False),
+    ):
         determine_jobs.main()
 
     # Check that functions were called with branch
@@ -363,16 +375,6 @@ def test_should_run_clang_tidy_hash_check_exception() -> None:
         result = determine_jobs.should_run_clang_tidy()
         assert result is True  # Fail safe - run clang-tidy
 
-    # Even with C++ files, exception should trigger clang-tidy
-    with (
-        patch.object(
-            determine_jobs, "changed_files", return_value=["esphome/core.cpp"]
-        ),
-        patch("subprocess.run", side_effect=Exception("Hash check failed")),
-    ):
-        result = determine_jobs.should_run_clang_tidy()
-        assert result is True
-
 
 def test_should_run_clang_tidy_with_branch() -> None:
     """Test should_run_clang_tidy with branch argument."""
@@ -763,3 +765,120 @@ def test_detect_memory_impact_config_skips_base_bus_components(tmp_path: Path) -
     assert result["should_run"] == "true"
     assert result["components"] == ["wifi"]
     assert "i2c" not in result["components"]
+
+
+# Tests for clang-tidy split mode logic
+
+
+def test_clang_tidy_mode_full_scan(
+    mock_should_run_integration_tests: Mock,
+    mock_should_run_clang_tidy: Mock,
+    mock_should_run_clang_format: Mock,
+    mock_should_run_python_linters: Mock,
+    mock_subprocess_run: Mock,
+    mock_changed_files: Mock,
+    capsys: pytest.CaptureFixture[str],
+    monkeypatch: pytest.MonkeyPatch,
+) -> None:
+    """Test that full scan (hash changed) always uses split mode."""
+    monkeypatch.delenv("GITHUB_ACTIONS", raising=False)
+
+    mock_should_run_integration_tests.return_value = False
+    mock_should_run_clang_tidy.return_value = True
+    mock_should_run_clang_format.return_value = False
+    mock_should_run_python_linters.return_value = False
+
+    # Mock list-components.py output
+    mock_result = Mock()
+    mock_result.stdout = json.dumps({"directly_changed": [], "all_changed": []})
+    mock_subprocess_run.return_value = mock_result
+
+    # Mock full scan (hash changed)
+    with (
+        patch("sys.argv", ["determine-jobs.py"]),
+        patch.object(determine_jobs, "_is_clang_tidy_full_scan", return_value=True),
+    ):
+        determine_jobs.main()
+
+    captured = capsys.readouterr()
+    output = json.loads(captured.out)
+
+    # Full scan should always use split mode
+    assert output["clang_tidy_mode"] == "split"
+
+
+@pytest.mark.parametrize(
+    ("component_count", "files_per_component", "expected_mode"),
+    [
+        # Small PR: 5 files in 1 component -> nosplit
+        (1, 5, "nosplit"),
+        # Medium PR: 30 files in 2 components -> nosplit
+        (2, 15, "nosplit"),
+        # Medium PR: 64 files total -> nosplit (just under threshold)
+        (2, 32, "nosplit"),
+        # Large PR: 65 files total -> split (at threshold)
+        (2, 33, "split"),  # 2 * 33 = 66 files
+        # Large PR: 100 files in 10 components -> split
+        (10, 10, "split"),
+    ],
+    ids=[
+        "1_comp_5_files_nosplit",
+        "2_comp_30_files_nosplit",
+        "2_comp_64_files_nosplit_under_threshold",
+        "2_comp_66_files_split_at_threshold",
+        "10_comp_100_files_split",
+    ],
+)
+def test_clang_tidy_mode_targeted_scan(
+    component_count: int,
+    files_per_component: int,
+    expected_mode: str,
+    mock_should_run_integration_tests: Mock,
+    mock_should_run_clang_tidy: Mock,
+    mock_should_run_clang_format: Mock,
+    mock_should_run_python_linters: Mock,
+    mock_subprocess_run: Mock,
+    mock_changed_files: Mock,
+    capsys: pytest.CaptureFixture[str],
+    monkeypatch: pytest.MonkeyPatch,
+) -> None:
+    """Test clang-tidy mode selection based on files_to_check count."""
+    monkeypatch.delenv("GITHUB_ACTIONS", raising=False)
+
+    mock_should_run_integration_tests.return_value = False
+    mock_should_run_clang_tidy.return_value = True
+    mock_should_run_clang_format.return_value = False
+    mock_should_run_python_linters.return_value = False
+
+    # Create component names
+    components = [f"comp{i}" for i in range(component_count)]
+
+    # Mock list-components.py output
+    mock_result = Mock()
+    mock_result.stdout = json.dumps(
+        {"directly_changed": components, "all_changed": components}
+    )
+    mock_subprocess_run.return_value = mock_result
+
+    # Mock git_ls_files to return files for each component
+    cpp_files = {
+        f"esphome/components/{comp}/file{i}.cpp": 0
+        for comp in components
+        for i in range(files_per_component)
+    }
+
+    # Create a mock that returns the cpp_files dict for any call
+    def mock_git_ls_files(patterns=None):
+        return cpp_files
+
+    with (
+        patch("sys.argv", ["determine-jobs.py"]),
+        patch.object(determine_jobs, "_is_clang_tidy_full_scan", return_value=False),
+        patch.object(determine_jobs, "git_ls_files", side_effect=mock_git_ls_files),
+    ):
+        determine_jobs.main()
+
+    captured = capsys.readouterr()
+    output = json.loads(captured.out)
+
+    assert output["clang_tidy_mode"] == expected_mode

tests/unit_tests/core/test_config.py

@@ -517,6 +517,35 @@ def test_include_file_cpp(tmp_path: Path, mock_copy_file_if_changed: Mock) -> No
         mock_cg.add_global.assert_not_called()
 
 
+def test_include_file_with_c_header(
+    tmp_path: Path, mock_copy_file_if_changed: Mock
+) -> None:
+    """Test include_file wraps header in extern C block when is_c_header is True."""
+    src_file = tmp_path / "c_library.h"
+    src_file.write_text("// C library header")
+
+    CORE.build_path = tmp_path / "build"
+
+    with patch("esphome.core.config.cg") as mock_cg:
+        # Mock RawStatement to capture the text
+        mock_raw_statement = MagicMock()
+        mock_raw_statement.text = ""
+
+        def raw_statement_side_effect(text):
+            mock_raw_statement.text = text
+            return mock_raw_statement
+
+        mock_cg.RawStatement.side_effect = raw_statement_side_effect
+
+        config.include_file(src_file, Path("c_library.h"), is_c_header=True)
+
+        mock_copy_file_if_changed.assert_called_once()
+        mock_cg.add_global.assert_called_once()
+        # Check that include statement is wrapped in extern "C" block
+        assert 'extern "C"' in mock_raw_statement.text
+        assert '#include "c_library.h"' in mock_raw_statement.text
+
+
 def test_get_usable_cpu_count() -> None:
     """Test get_usable_cpu_count returns CPU count."""
     count = config.get_usable_cpu_count()