difftastic/vendored_parsers/tree-sitter-hack/test/cases/expressions/update.exp

(script
  (expression_statement
    (prefix_unary_expression
      operand: (variable)))
  (expression_statement
    (prefix_unary_expression
      operand: (variable)))
  (expression_statement
    (postfix_unary_expression
      (variable)))
  (expression_statement
    (postfix_unary_expression
      (variable))))