[lvgl] Fix lambdas in canvas actions called from outside LVGL context (#12671)

esphome/components/lvgl/defines.py

@@ -5,7 +5,7 @@ Constants already defined in esphome.const are not duplicated here and must be i
 """
 
 import logging
-from typing import TYPE_CHECKING, Any
+from typing import Any
 
 from esphome import codegen as cg, config_validation as cv
 from esphome.const import CONF_ITEMS
@@ -96,13 +96,9 @@ class LValidator:
             return None
         if isinstance(value, Lambda):
             # Local import to avoid circular import
-            from .lvcode import CodeContext, LambdaContext
+            from .lvcode import get_lambda_context_args
 
-            if TYPE_CHECKING:
-                # CodeContext does not have get_automation_parameters
-                # so we need to assert the type here
-                assert isinstance(CodeContext.code_context, LambdaContext)
-            args = args or CodeContext.code_context.get_automation_parameters()
+            args = args or get_lambda_context_args()
             return cg.RawExpression(
                 call_lambda(
                     await cg.process_lambda(value, args, return_type=self.rtype)

esphome/components/lvgl/lv_validation.py

@@ -1,5 +1,5 @@
 import re
-from typing import TYPE_CHECKING, Any
+from typing import Any
 
 import esphome.codegen as cg
 from esphome.components import image
@@ -404,14 +404,9 @@ class TextValidator(LValidator):
         self, value: Any, args: list[tuple[SafeExpType, str]] | None = None
     ) -> Expression:
         # Local import to avoid circular import at module level
+        from .lvcode import get_lambda_context_args
 
-        from .lvcode import CodeContext, LambdaContext
-
-        if TYPE_CHECKING:
-            # CodeContext does not have get_automation_parameters
-            # so we need to assert the type here
-            assert isinstance(CodeContext.code_context, LambdaContext)
-        args = args or CodeContext.code_context.get_automation_parameters()
+        args = args or get_lambda_context_args()
 
         if isinstance(value, dict):
             if format_str := value.get(CONF_FORMAT):

esphome/components/lvgl/lvcode.py

@@ -1,4 +1,5 @@
 import abc
+from typing import TYPE_CHECKING
 
 from esphome import codegen as cg
 from esphome.config import Config
@@ -200,6 +201,21 @@ class LvContext(LambdaContext):
         return self.add(*args)
 
 
+def get_lambda_context_args() -> list[tuple[SafeExpType, str]]:
+    """Get automation parameters from the current lambda context if available.
+
+    When called from outside LVGL's context (e.g., from interval),
+    CodeContext.code_context will be None, so return empty args.
+    """
+    if CodeContext.code_context is None:
+        return []
+    if TYPE_CHECKING:
+        # CodeContext base class doesn't define get_automation_parameters(),
+        # but LambdaContext and LvContext (the concrete implementations) do.
+        assert isinstance(CodeContext.code_context, LambdaContext)
+    return CodeContext.code_context.get_automation_parameters()
+
+
 class LocalVariable(MockObj):
     """
     Create a local variable and enclose the code using it within a block.