[esp32] Keep the sscanf wrap independent of enable_full_printf and say the override aborts

esphome/components/esp32/__init__.py

@@ -2337,9 +2337,15 @@ async def _add_sscanf_stub(enable_full_scanf: bool | None, variant: str) -> None
 
     FINAL priority so every request_bluetooth() call has happened.
     """
-    if variant in ROM_SSCANF_VARIANTS or not _network_sdkconfig().bluetooth:
+    if (
+        variant in ROM_SSCANF_VARIANTS
+        or idf_version() >= cv.Version(6, 0, 0)  # picolibc, unmeasured
+        or not _network_sdkconfig().bluetooth
+    ):
         return
-    if keep_float_scanf(enable_full_scanf, CORE.config, "~13KB flash"):
+    if keep_float_scanf(
+        enable_full_scanf, CORE.config, "~13KB flash", "that call will abort the device"
+    ):
         return
     _add_wrap_stub("sscanf", "USE_ESP32_SSCANF_STUB")
 
@@ -2702,12 +2708,12 @@ async def to_code(config):
             # ROM. See vasprintf_stubs.cpp.
             if variant in ROM_VSNPRINTF_WITHOUT_VASPRINTF_VARIANTS:
                 _add_wrap_stub("vasprintf", "USE_ESP32_VASPRINTF_STUB")
-            # bluedroid's sscanf calls; see sscanf_stubs.cpp
-            CORE.add_job(
-                _add_sscanf_stub,
-                conf[CONF_ADVANCED].get(CONF_ENABLE_FULL_SCANF),
-                variant,
-            )
+        # bluedroid's sscanf calls; see sscanf_stubs.cpp
+        CORE.add_job(
+            _add_sscanf_stub,
+            conf[CONF_ADVANCED].get(CONF_ENABLE_FULL_SCANF),
+            variant,
+        )
     else:
         cg.add_build_flag("-DUSE_ARDUINO")
         cg.add_build_flag("-DUSE_ESP32_FRAMEWORK_ARDUINO")

esphome/components/esp8266/__init__.py

@@ -274,7 +274,10 @@ async def to_code(config: ConfigType) -> None:
     cg.add_define("USE_ESP8266_CRASH_HANDLER")
 
     enable_scanf_float = keep_float_scanf(
-        config.get(CONF_ENABLE_SCANF_FLOAT), CORE.config, "~8KB flash"
+        config.get(CONF_ENABLE_SCANF_FLOAT),
+        CORE.config,
+        "~8KB flash",
+        "that call will not parse",
     )
 
     extra_scripts = [

esphome/config_helpers.py

@@ -278,10 +278,13 @@ def user_code_uses_scanf_float(config: ConfigType) -> bool:
     return lambdas_use_scanf_float(config) or includes_use_scanf_float(config)
 
 
-def keep_float_scanf(option: bool | None, config: ConfigType, flash_note: str) -> bool:
+def keep_float_scanf(
+    option: bool | None, config: ConfigType, flash_note: str, override_note: str
+) -> bool:
     """Resolve a tri-state float-scanf option: unset means "only if user code scans a float".
 
-    Logs when user code decides it, or when an explicit ``false`` overrides it.
+    Logs when user code decides it, or (with ``override_note``, the consequence)
+    when an explicit ``false`` overrides it.
     """
     if option is None:
         if not user_code_uses_scanf_float(config):
@@ -295,6 +298,7 @@ def keep_float_scanf(option: bool | None, config: ConfigType, flash_note: str) -
     if not option and user_code_uses_scanf_float(config):
         _LOGGER.warning(
             "Float scanf support is disabled but a lambda or include uses scanf "
-            "with a float format specifier; that call will not parse"
+            "with a float format specifier; %s",
+            override_note,
         )
     return option

tests/component_tests/esp32/config/sscanf_stub_ble_full_printf.yaml

@@ -0,0 +1,11 @@
+esphome:
+  name: test
+
+esp32:
+  board: esp32dev
+  framework:
+    type: esp-idf
+    advanced:
+      enable_full_printf: true
+
+esp32_ble_tracker:

tests/component_tests/esp32/test_esp32.py

@@ -1449,6 +1449,9 @@ def test_mbedtls_tls_openthread_requires_server_and_extras(
             id="sscanf_lambda_float_forced",
         ),
         pytest.param("sscanf_stub_ble_c2.yaml", "sscanf", False, id="sscanf_c2_rom"),
+        pytest.param(
+            "sscanf_stub_ble_full_printf.yaml", "sscanf", True, id="sscanf_full_printf"
+        ),
         pytest.param("exclusion_reincludes.yaml", "sscanf", False, id="sscanf_no_ble"),
     ],
 )

tests/unit_tests/test_config_helpers.py

@@ -288,7 +288,7 @@ def test_keep_float_scanf() -> None:
     """Explicit values win; unset follows whether user code scans a float."""
     float_config: ConfigType = {"test": [Lambda('sscanf(b, "%f", &v)')]}
     int_config: ConfigType = {"test": [Lambda('sscanf(b, "%d", &v)')]}
-    assert keep_float_scanf(True, int_config, "x") is True
-    assert keep_float_scanf(False, float_config, "x") is False
-    assert keep_float_scanf(None, float_config, "x") is True
-    assert keep_float_scanf(None, int_config, "x") is False
+    assert keep_float_scanf(True, int_config, "x", "y") is True
+    assert keep_float_scanf(False, float_config, "x", "y") is False
+    assert keep_float_scanf(None, float_config, "x", "y") is True
+    assert keep_float_scanf(None, int_config, "x", "y") is False