[lvgl] Improve error messages from text validation (#8872)

esphome/components/lvgl/schemas.py

@@ -36,29 +36,43 @@ from .types import (
 # this will be populated later, in __init__.py to avoid circular imports.
 WIDGET_TYPES: dict = {}
 
+TIME_TEXT_SCHEMA = cv.Schema(
+    {
+        cv.Required(CONF_TIME_FORMAT): cv.string,
+        cv.GenerateID(CONF_TIME): cv.templatable(cv.use_id(RealTimeClock)),
+    }
+)
+
+PRINTF_TEXT_SCHEMA = cv.All(
+    cv.Schema(
+        {
+            cv.Required(CONF_FORMAT): cv.string,
+            cv.Optional(CONF_ARGS, default=list): cv.ensure_list(cv.lambda_),
+        },
+    ),
+    validate_printf,
+)
+
+
+def _validate_text(value):
+    """
+    Do some sanity checking of the format to get better error messages
+    than using cv.Any
+    """
+    if value is None:
+        raise cv.Invalid("No text specified")
+    if isinstance(value, dict):
+        if CONF_TIME_FORMAT in value:
+            return TIME_TEXT_SCHEMA(value)
+        return PRINTF_TEXT_SCHEMA(value)
+
+    return cv.templatable(cv.string)(value)
+
+
 # A schema for text properties
 TEXT_SCHEMA = cv.Schema(
     {
-        cv.Optional(CONF_TEXT): cv.Any(
+        cv.Optional(CONF_TEXT): _validate_text,
-            cv.All(
-                cv.Schema(
-                    {
-                        cv.Required(CONF_FORMAT): cv.string,
-                        cv.Optional(CONF_ARGS, default=list): cv.ensure_list(
-                            cv.lambda_
-                        ),
-                    },
-                ),
-                validate_printf,
-            ),
-            cv.Schema(
-                {
-                    cv.Required(CONF_TIME_FORMAT): cv.string,
-                    cv.GenerateID(CONF_TIME): cv.templatable(cv.use_id(RealTimeClock)),
-                }
-            ),
-            cv.templatable(cv.string),
-        )
     }
 )