tests/test_c_ast.py

import pprint
import re
import sys
import unittest
import weakref

sys.path.insert(0, '..')
import pycparser.c_ast as c_ast
import pycparser.plyparser as plyparser


class Test_c_ast(unittest.TestCase):
    def test_BinaryOp(self):
        b1 = c_ast.BinaryOp(
            op='+',
            left=c_ast.Constant(type='int', value='6'),
            right=c_ast.ID(name='joe'))

        self.failUnless(isinstance(b1.left, c_ast.Constant))
        self.assertEqual(b1.left.type, 'int')
        self.assertEqual(b1.left.value, '6')

        self.failUnless(isinstance(b1.right, c_ast.ID))
        self.assertEqual(b1.right.name, 'joe')

    def test_weakref_works_on_nodes(self):
        c1 = c_ast.Constant(type='float', value='3.14')
        wr = weakref.ref(c1)
        cref = wr()
        self.assertEqual(cref.type, 'float')
        self.assertEqual(weakref.getweakrefcount(c1), 1)

    def test_weakref_works_on_coord(self):
        coord = plyparser.Coord(file='a', line=2)
        wr = weakref.ref(coord)
        cref = wr()
        self.assertEqual(cref.line, 2)
        self.assertEqual(weakref.getweakrefcount(coord), 1)



class TestNodeVisitor(unittest.TestCase):
    class ConstantVisitor(c_ast.NodeVisitor):
        def __init__(self):
            self.values = []

        def visit_Constant(self, node):
            self.values.append(node.value)

    def test_scalar_children(self):
        b1 = c_ast.BinaryOp(
            op='+',
            left=c_ast.Constant(type='int', value='6'),
            right=c_ast.ID(name='joe'))

        cv = self.ConstantVisitor()
        cv.visit(b1)

        self.assertEqual(cv.values, ['6'])

        b2 = c_ast.BinaryOp(
            op='*',
            left=c_ast.Constant(type='int', value='111'),
            right=b1)

        b3 = c_ast.BinaryOp(
            op='^',
            left=b2,
            right=b1)

        cv = self.ConstantVisitor()
        cv.visit(b3)

        self.assertEqual(cv.values, ['111', '6', '6'])

    def tests_list_children(self):
        c1 = c_ast.Constant(type='float', value='5.6')
        c2 = c_ast.Constant(type='char', value='t')

        b1 = c_ast.BinaryOp(
            op='+',
            left=c1,
            right=c2)

        b2 = c_ast.BinaryOp(
            op='-',
            left=b1,
            right=c2)

        comp = c_ast.Compound(
            block_items=[b1, b2, c1, c2])

        cv = self.ConstantVisitor()
        cv.visit(comp)

        self.assertEqual(cv.values,
            ['5.6', 't', '5.6', 't', 't', '5.6', 't'])


if __name__ == '__main__':
    unittest.main()