cpython/Lib/test/test_symtable.py

"""
Test the API of the symtable module.
"""
import symtable
import unittest

from test import support
from test.support import os_helper


TEST_CODE = """
import sys

glob = 42
some_var = 12
some_non_assigned_global_var = 11
some_assigned_global_var = 11

class Mine:
    instance_var = 24
    def a_method(p1, p2):
        pass

def spam(a, b, *var, **kw):
    global bar
    global some_assigned_global_var
    some_assigned_global_var = 12
    bar = 47
    some_var = 10
    x = 23
    glob
    def internal():
        return x
    def other_internal():
        nonlocal some_var
        some_var = 3
        return some_var
    return internal

def foo():
    pass

def namespace_test(): pass
def namespace_test(): pass

type Alias = int
type GenericAlias[T] = list[T]

def generic_spam[T](a):
    pass

class GenericMine[T: int]:
    pass
"""


def find_block(block, name):
    for ch in block.get_children():
        if ch.get_name() == name:
            return ch


class SymtableTest(unittest.TestCase):

    top = symtable.symtable(TEST_CODE, "?", "exec")
    # These correspond to scopes in TEST_CODE
    Mine = find_block(top, "Mine")
    a_method = find_block(Mine, "a_method")
    spam = find_block(top, "spam")
    internal = find_block(spam, "internal")
    other_internal = find_block(spam, "other_internal")
    foo = find_block(top, "foo")
    Alias = find_block(top, "Alias")
    GenericAlias = find_block(top, "GenericAlias")
    GenericAlias_inner = find_block(GenericAlias, "GenericAlias")
    generic_spam = find_block(top, "generic_spam")
    generic_spam_inner = find_block(generic_spam, "generic_spam")
    GenericMine = find_block(top, "GenericMine")
    GenericMine_inner = find_block(GenericMine, "GenericMine")
    T = find_block(GenericMine, "T")

    def test_type(self):
        self.assertEqual(self.top.get_type(), "module")
        self.assertEqual(self.Mine.get_type(), "class")
        self.assertEqual(self.a_method.get_type(), "function")
        self.assertEqual(self.spam.get_type(), "function")
        self.assertEqual(self.internal.get_type(), "function")
        self.assertEqual(self.foo.get_type(), "function")
        self.assertEqual(self.Alias.get_type(), "type alias")
        self.assertEqual(self.GenericAlias.get_type(), "type parameter")
        self.assertEqual(self.GenericAlias_inner.get_type(), "type alias")
        self.assertEqual(self.generic_spam.get_type(), "type parameter")
        self.assertEqual(self.generic_spam_inner.get_type(), "function")
        self.assertEqual(self.GenericMine.get_type(), "type parameter")
        self.assertEqual(self.GenericMine_inner.get_type(), "class")
        self.assertEqual(self.T.get_type(), "TypeVar bound")

    def test_id(self):
        self.assertGreater(self.top.get_id(), 0)
        self.assertGreater(self.Mine.get_id(), 0)
        self.assertGreater(self.a_method.get_id(), 0)
        self.assertGreater(self.spam.get_id(), 0)
        self.assertGreater(self.internal.get_id(), 0)
        self.assertGreater(self.foo.get_id(), 0)
        self.assertGreater(self.Alias.get_id(), 0)
        self.assertGreater(self.GenericAlias.get_id(), 0)
        self.assertGreater(self.generic_spam.get_id(), 0)
        self.assertGreater(self.GenericMine.get_id(), 0)

    def test_optimized(self):
        self.assertFalse(self.top.is_optimized())

        self.assertTrue(self.spam.is_optimized())

    def test_nested(self):
        self.assertFalse(self.top.is_nested())
        self.assertFalse(self.Mine.is_nested())
        self.assertFalse(self.spam.is_nested())
        self.assertTrue(self.internal.is_nested())

    def test_children(self):
        self.assertTrue(self.top.has_children())
        self.assertTrue(self.Mine.has_children())
        self.assertFalse(self.foo.has_children())

    def test_lineno(self):
        self.assertEqual(self.top.get_lineno(), 0)
        self.assertEqual(self.spam.get_lineno(), 14)

    def test_function_info(self):
        func = self.spam
        self.assertEqual(sorted(func.get_parameters()), ["a", "b", "kw", "var"])
        expected = ['a', 'b', 'internal', 'kw', 'other_internal', 'some_var', 'var', 'x']
        self.assertEqual(sorted(func.get_locals()), expected)
        self.assertEqual(sorted(func.get_globals()), ["bar", "glob", "some_assigned_global_var"])
        self.assertEqual(self.internal.get_frees(), ("x",))

    def test_globals(self):
        self.assertTrue(self.spam.lookup("glob").is_global())
        self.assertFalse(self.spam.lookup("glob").is_declared_global())
        self.assertTrue(self.spam.lookup("bar").is_global())
        self.assertTrue(self.spam.lookup("bar").is_declared_global())
        self.assertFalse(self.internal.lookup("x").is_global())
        self.assertFalse(self.Mine.lookup("instance_var").is_global())
        self.assertTrue(self.spam.lookup("bar").is_global())
        # Module-scope globals are both global and local
        self.assertTrue(self.top.lookup("some_non_assigned_global_var").is_global())
        self.assertTrue(self.top.lookup("some_assigned_global_var").is_global())

    def test_nonlocal(self):
        self.assertFalse(self.spam.lookup("some_var").is_nonlocal())
        self.assertTrue(self.other_internal.lookup("some_var").is_nonlocal())
        expected = ("some_var",)
        self.assertEqual(self.other_internal.get_nonlocals(), expected)

    def test_local(self):
        self.assertTrue(self.spam.lookup("x").is_local())
        self.assertFalse(self.spam.lookup("bar").is_local())
        # Module-scope globals are both global and local
        self.assertTrue(self.top.lookup("some_non_assigned_global_var").is_local())
        self.assertTrue(self.top.lookup("some_assigned_global_var").is_local())

    def test_free(self):
        self.assertTrue(self.internal.lookup("x").is_free())

    def test_referenced(self):
        self.assertTrue(self.internal.lookup("x").is_referenced())
        self.assertTrue(self.spam.lookup("internal").is_referenced())
        self.assertFalse(self.spam.lookup("x").is_referenced())

    def test_parameters(self):
        for sym in ("a", "var", "kw"):
            self.assertTrue(self.spam.lookup(sym).is_parameter())
        self.assertFalse(self.spam.lookup("x").is_parameter())

    def test_symbol_lookup(self):
        self.assertEqual(len(self.top.get_identifiers()),
                         len(self.top.get_symbols()))

        self.assertRaises(KeyError, self.top.lookup, "not_here")

    def test_namespaces(self):
        self.assertTrue(self.top.lookup("Mine").is_namespace())
        self.assertTrue(self.Mine.lookup("a_method").is_namespace())
        self.assertTrue(self.top.lookup("spam").is_namespace())
        self.assertTrue(self.spam.lookup("internal").is_namespace())
        self.assertTrue(self.top.lookup("namespace_test").is_namespace())
        self.assertFalse(self.spam.lookup("x").is_namespace())

        self.assertTrue(self.top.lookup("spam").get_namespace() is self.spam)
        ns_test = self.top.lookup("namespace_test")
        self.assertEqual(len(ns_test.get_namespaces()), 2)
        self.assertRaises(ValueError, ns_test.get_namespace)

        ns_test_2 = self.top.lookup("glob")
        self.assertEqual(len(ns_test_2.get_namespaces()), 0)
        self.assertRaises(ValueError, ns_test_2.get_namespace)

    def test_assigned(self):
        self.assertTrue(self.spam.lookup("x").is_assigned())
        self.assertTrue(self.spam.lookup("bar").is_assigned())
        self.assertTrue(self.top.lookup("spam").is_assigned())
        self.assertTrue(self.Mine.lookup("a_method").is_assigned())
        self.assertFalse(self.internal.lookup("x").is_assigned())

    def test_annotated(self):
        st1 = symtable.symtable('def f():\n    x: int\n', 'test', 'exec')
        st2 = st1.get_children()[0]
        self.assertTrue(st2.lookup('x').is_local())
        self.assertTrue(st2.lookup('x').is_annotated())
        self.assertFalse(st2.lookup('x').is_global())
        st3 = symtable.symtable('def f():\n    x = 1\n', 'test', 'exec')
        st4 = st3.get_children()[0]
        self.assertTrue(st4.lookup('x').is_local())
        self.assertFalse(st4.lookup('x').is_annotated())

        # Test that annotations in the global scope are valid after the
        # variable is declared as nonlocal.
        st5 = symtable.symtable('global x\nx: int', 'test', 'exec')
        self.assertTrue(st5.lookup("x").is_global())

        # Test that annotations for nonlocals are valid after the
        # variable is declared as nonlocal.
        st6 = symtable.symtable('def g():\n'
                                '    x = 2\n'
                                '    def f():\n'
                                '        nonlocal x\n'
                                '    x: int',
                                'test', 'exec')

    def test_imported(self):
        self.assertTrue(self.top.lookup("sys").is_imported())

    def test_name(self):
        self.assertEqual(self.top.get_name(), "top")
        self.assertEqual(self.spam.get_name(), "spam")
        self.assertEqual(self.spam.lookup("x").get_name(), "x")
        self.assertEqual(self.Mine.get_name(), "Mine")

    def test_class_info(self):
        self.assertEqual(self.Mine.get_methods(), ('a_method',))

    def test_filename_correct(self):
        ### Bug tickler: SyntaxError file name correct whether error raised
        ### while parsing or building symbol table.
        def checkfilename(brokencode, offset):
            try:
                symtable.symtable(brokencode, "spam", "exec")
            except SyntaxError as e:
                self.assertEqual(e.filename, "spam")
                self.assertEqual(e.lineno, 1)
                self.assertEqual(e.offset, offset)
            else:
                self.fail("no SyntaxError for %r" % (brokencode,))
        checkfilename("def f(x): foo)(", 14)  # parse-time
        checkfilename("def f(x): global x", 11)  # symtable-build-time
        symtable.symtable("pass", b"spam", "exec")
        with self.assertRaises(TypeError):
            symtable.symtable("pass", bytearray(b"spam"), "exec")
        with self.assertRaises(TypeError):
            symtable.symtable("pass", memoryview(b"spam"), "exec")
        with self.assertRaises(TypeError):
            symtable.symtable("pass", list(b"spam"), "exec")

    def test_eval(self):
        symbols = symtable.symtable("42", "?", "eval")

    def test_single(self):
        symbols = symtable.symtable("42", "?", "single")

    def test_exec(self):
        symbols = symtable.symtable("def f(x): return x", "?", "exec")

    def test_bytes(self):
        top = symtable.symtable(TEST_CODE.encode('utf8'), "?", "exec")
        self.assertIsNotNone(find_block(top, "Mine"))

        code = b'# -*- coding: iso8859-15 -*-\nclass \xb4: pass\n'

        top = symtable.symtable(code, "?", "exec")
        self.assertIsNotNone(find_block(top, "\u017d"))

    def test_symtable_repr(self):
        self.assertEqual(str(self.top), "<SymbolTable for module ?>")
        self.assertEqual(str(self.spam), "<Function SymbolTable for spam in ?>")

    def test_symbol_repr(self):
        self.assertEqual(repr(self.spam.lookup("glob")),
                         "<symbol 'glob': GLOBAL_IMPLICIT, USE>")
        self.assertEqual(repr(self.spam.lookup("bar")),
                         "<symbol 'bar': GLOBAL_EXPLICIT, DEF_GLOBAL|DEF_LOCAL>")
        self.assertEqual(repr(self.spam.lookup("a")),
                         "<symbol 'a': LOCAL, DEF_PARAM>")
        self.assertEqual(repr(self.spam.lookup("internal")),
                         "<symbol 'internal': LOCAL, USE|DEF_LOCAL>")
        self.assertEqual(repr(self.spam.lookup("other_internal")),
                         "<symbol 'other_internal': LOCAL, DEF_LOCAL>")
        self.assertEqual(repr(self.internal.lookup("x")),
                         "<symbol 'x': FREE, USE>")
        self.assertEqual(repr(self.other_internal.lookup("some_var")),
                         "<symbol 'some_var': FREE, USE|DEF_NONLOCAL|DEF_LOCAL>")

    def test_symtable_entry_repr(self):
        expected = f"<symtable entry top({self.top.get_id()}), line {self.top.get_lineno()}>"
        self.assertEqual(repr(self.top._table), expected)


class CommandLineTest(unittest.TestCase):
    maxDiff = None

    def test_file(self):
        filename = os_helper.TESTFN
        self.addCleanup(os_helper.unlink, filename)
        with open(filename, 'w') as f:
            f.write(TEST_CODE)
        with support.captured_stdout() as stdout:
            symtable.main([filename])
        out = stdout.getvalue()
        self.assertIn('\n\n', out)
        self.assertNotIn('\n\n\n', out)
        lines = out.splitlines()
        self.assertIn(f"symbol table for module from file {filename!r}:", lines)
        self.assertIn("    local symbol 'glob': def_local", lines)
        self.assertIn("        global_implicit symbol 'glob': use", lines)
        self.assertIn("    local symbol 'spam': def_local", lines)
        self.assertIn("    symbol table for function 'spam':", lines)

    def test_stdin(self):
        with support.captured_stdin() as stdin:
            stdin.write(TEST_CODE)
            stdin.seek(0)
            with support.captured_stdout() as stdout:
                symtable.main([])
            out = stdout.getvalue()
            stdin.seek(0)
            with support.captured_stdout() as stdout:
                symtable.main(['-'])
            self.assertEqual(stdout.getvalue(), out)
        lines = out.splitlines()
        self.assertIn("symbol table for module from file '<stdin>':", lines)


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