def test_freevars(self):
env = Env()
env = env.extend('a', 3)
env = env.extend('b', 17)
env = env.extend('c', 6)
for x in range(10):
env = env.extend('b', x)
env = env.extend('b', 55)
env = env.extend('c', 12)
self.assertEqual(3, env['a'])
self.assertEqual(55, env['b'])
self.assertEqual(12, env['c'])
# Check local stack does not have excessive content
self.assertEqual(3, len(env.local_stack))
def test_shadowing(self):
env = Env()
new_env_a = env.extend('x', 2)
new_env_b = new_env_a.extend('x', 5)
# Make sure new_env didnt change, but new_env_2 did
with self.assertRaises(ValueError):
env['x']
self.assertEqual(2, new_env_a['x'])
self.assertEqual(5, new_env_b['x'])
def test_extend(self):
env = Env()
env['a'] = 1
new_env = env.extend('x', 2)
# Original environment should not change
self.assertEqual(1, env['a'])
with self.assertRaises(ValueError):
env['x']
self.assertEqual(1, new_env['a'])
self.assertEqual(2, new_env['x'])
def test_set_local_doesnt_bleed(self):
env = Env()
env['a'] = 12 # Global frame
extended_env = env.extend('a', 16) # local shadowing
self.assertEqual(12, env['a'])
self.assertEqual(16, extended_env['a'])
# Now update global 'a' in original env - check it doesnt bleed into extended
env['a'] = 50
self.assertEqual(50, env['a'])
self.assertEqual(16, extended_env['a'])
# Update 'a' in extended_env, check no bleeding again
extended_env.set_local('a', 46)
self.assertEqual(50, env['a'])
self.assertEqual(46, extended_env['a'])
def test_contains(self):
env = Env()
self.assertFalse('a' in env)
extended_env = env.extend('a', 16)
self.assertFalse('a' in env)
self.assertTrue('a' in extended_env)
