Fixed Syntax validation and autocompletion. Fixed unit tests

src/myfasthtml/core/dsl/base_completion.py

@@ -128,8 +128,8 @@ class BaseCompletionEngine(ABC):
     Generate suggestions for the given context.
 
     Args:
-        context: The detected completion context
-        scope: The detected scope
+        context: The detected completion context (from the parser)
+        scope: The detected scope (table, column, row, cell...)
         prefix: The current word prefix (for filtering)
 
     Returns:

src/myfasthtml/core/dsl/exceptions.py

@@ -0,0 +1,50 @@
+"""
+Common DSL exceptions shared across all DSL implementations.
+"""
+
+
+class DSLError(Exception):
+  """Base exception for DSL errors."""
+  pass
+
+
+class DSLSyntaxError(DSLError):
+  """
+  Raised when a DSL input has syntax errors.
+
+  Attributes:
+      message: Error description
+      line: Line number where error occurred (1-based)
+      column: Column number where error occurred (1-based)
+      context: The problematic line or snippet
+  """
+  
+  def __init__(self, message: str, line: int = None, column: int = None, context: str = None):
+    self.message = message
+    self.line = line
+    self.column = column
+    self.context = context
+    super().__init__(self._format_message())
+  
+  def _format_message(self) -> str:
+    parts = [self.message]
+    if self.line is not None:
+      parts.append(f"at line {self.line}")
+      if self.column is not None:
+        parts[1] = f"at line {self.line}, column {self.column}"
+    if self.context:
+      parts.append(f"\n  {self.context}")
+      if self.column is not None:
+        parts.append(f"\n  {' ' * (self.column - 1)}^")
+    return " ".join(parts[:2]) + "".join(parts[2:])
+
+
+class DSLValidationError(DSLError):
+  """
+  Raised when a DSL is syntactically correct but semantically invalid.
+  """
+  
+  def __init__(self, message: str, line: int = None):
+    self.message = message
+    self.line = line
+    super().__init__(f"{message}" + (f" at line {line}" if line else ""))