message: Fix edge case check for transitions.
diff: @@ -504,7 +504,7 @@ export class Lexer {
  modeStack.length === 1 &&
  // if we have both a POP_MODE and a PUSH_MODE this is in-fact a "transition"
  // So no error should occur.
  - popToken.PUSH_MODE === undefined
  + popToken.type.PUSH_MODE === undefined
  ) {
  // if we try to pop the last mode there lexer will no longer have ANY mode.
  // thus the pop is ignored, an error will be created and the lexer will continue parsing in the previous mode.
  