def p_postfix_expression(self, p):
"""postfix_expression : left_hand_side_expression
| left_hand_side_expression PLUSPLUS
| left_hand_side_expression MINUSMINUS"""
if len(p) == 2:
p[0] = p[1]
else:
p[0] = ast.UnaryOp(op='postfix' + p[2], expression=p[1])
def p_unary_expression(self, p):
"""unary_expression : postfix_expression
| DELETE unary_expression
| VOID unary_expression
| TYPEOF unary_expression
| PLUSPLUS unary_expression
| MINUSMINUS unary_expression
| PLUS unary_expression
| MINUS unary_expression
| NOT unary_expression
| LNOT unary_expression"""
if len(p) == 2:
p[0] = p[1]
else:
p[0] = ast.UnaryOp(op=p[1], expression=p[2])
def test_parse_prefix_op(self):
self.assertEqual(
self.parser.parse('++x'),
ast.UnaryOp(op='++', expression=ast.Identifier(name='x')))
def test_parse_unary_op(self):
self.assertEqual(
self.parser.parse('+-1'),
ast.UnaryOp(op='+',
expression=ast.UnaryOp(
op='-', expression=ast.Literal(value=1))))