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      1 """Tests for the asdl parser in Parser/asdl.py"""
      2 
      3 import importlib.machinery
      4 import os
      5 from os.path import dirname
      6 import sys
      7 import sysconfig
      8 import unittest
      9 
     10 
     11 # This test is only relevant for from-source builds of Python.
     12 if not sysconfig.is_python_build():
     13     raise unittest.SkipTest('test irrelevant for an installed Python')
     14 
     15 src_base = dirname(dirname(dirname(__file__)))
     16 parser_dir = os.path.join(src_base, 'Parser')
     17 
     18 
     19 class TestAsdlParser(unittest.TestCase):
     20     @classmethod
     21     def setUpClass(cls):
     22         # Loads the asdl module dynamically, since it's not in a real importable
     23         # package.
     24         # Parses Python.asdl into an ast.Module and run the check on it.
     25         # There's no need to do this for each test method, hence setUpClass.
     26         sys.path.insert(0, parser_dir)
     27         loader = importlib.machinery.SourceFileLoader(
     28                 'asdl', os.path.join(parser_dir, 'asdl.py'))
     29         cls.asdl = loader.load_module()
     30         cls.mod = cls.asdl.parse(os.path.join(parser_dir, 'Python.asdl'))
     31         cls.assertTrue(cls.asdl.check(cls.mod), 'Module validation failed')
     32 
     33     @classmethod
     34     def tearDownClass(cls):
     35         del sys.path[0]
     36 
     37     def setUp(self):
     38         # alias stuff from the class, for convenience
     39         self.asdl = TestAsdlParser.asdl
     40         self.mod = TestAsdlParser.mod
     41         self.types = self.mod.types
     42 
     43     def test_module(self):
     44         self.assertEqual(self.mod.name, 'Python')
     45         self.assertIn('stmt', self.types)
     46         self.assertIn('expr', self.types)
     47         self.assertIn('mod', self.types)
     48 
     49     def test_definitions(self):
     50         defs = self.mod.dfns
     51         self.assertIsInstance(defs[0], self.asdl.Type)
     52         self.assertIsInstance(defs[0].value, self.asdl.Sum)
     53 
     54         self.assertIsInstance(self.types['withitem'], self.asdl.Product)
     55         self.assertIsInstance(self.types['alias'], self.asdl.Product)
     56 
     57     def test_product(self):
     58         alias = self.types['alias']
     59         self.assertEqual(
     60             str(alias),
     61             'Product([Field(identifier, name), Field(identifier, asname, opt=True)])')
     62 
     63     def test_attributes(self):
     64         stmt = self.types['stmt']
     65         self.assertEqual(len(stmt.attributes), 2)
     66         self.assertEqual(str(stmt.attributes[0]), 'Field(int, lineno)')
     67         self.assertEqual(str(stmt.attributes[1]), 'Field(int, col_offset)')
     68 
     69     def test_constructor_fields(self):
     70         ehandler = self.types['excepthandler']
     71         self.assertEqual(len(ehandler.types), 1)
     72         self.assertEqual(len(ehandler.attributes), 2)
     73 
     74         cons = ehandler.types[0]
     75         self.assertIsInstance(cons, self.asdl.Constructor)
     76         self.assertEqual(len(cons.fields), 3)
     77 
     78         f0 = cons.fields[0]
     79         self.assertEqual(f0.type, 'expr')
     80         self.assertEqual(f0.name, 'type')
     81         self.assertTrue(f0.opt)
     82 
     83         f1 = cons.fields[1]
     84         self.assertEqual(f1.type, 'identifier')
     85         self.assertEqual(f1.name, 'name')
     86         self.assertTrue(f1.opt)
     87 
     88         f2 = cons.fields[2]
     89         self.assertEqual(f2.type, 'stmt')
     90         self.assertEqual(f2.name, 'body')
     91         self.assertFalse(f2.opt)
     92         self.assertTrue(f2.seq)
     93 
     94     def test_visitor(self):
     95         class CustomVisitor(self.asdl.VisitorBase):
     96             def __init__(self):
     97                 super().__init__()
     98                 self.names_with_seq = []
     99 
    100             def visitModule(self, mod):
    101                 for dfn in mod.dfns:
    102                     self.visit(dfn)
    103 
    104             def visitType(self, type):
    105                 self.visit(type.value)
    106 
    107             def visitSum(self, sum):
    108                 for t in sum.types:
    109                     self.visit(t)
    110 
    111             def visitConstructor(self, cons):
    112                 for f in cons.fields:
    113                     if f.seq:
    114                         self.names_with_seq.append(cons.name)
    115 
    116         v = CustomVisitor()
    117         v.visit(self.types['mod'])
    118         self.assertEqual(v.names_with_seq, ['Module', 'Interactive', 'Suite'])
    119 
    120 
    121 if __name__ == '__main__':
    122     unittest.main()
    123