add a AST validator (closes #12575)
diff --git a/Lib/test/test_ast.py b/Lib/test/test_ast.py
index 77839c2..f56a44a 100644
--- a/Lib/test/test_ast.py
+++ b/Lib/test/test_ast.py
@@ -1,4 +1,6 @@
-import sys, unittest
+import os
+import sys
+import unittest
from test import support
import ast
@@ -490,8 +492,412 @@
self.assertEqual(ast.literal_eval('1.5 - 2j'), 1.5 - 2j)
+class ASTValidatorTests(unittest.TestCase):
+
+ def mod(self, mod, msg=None, mode="exec", *, exc=ValueError):
+ mod.lineno = mod.col_offset = 0
+ ast.fix_missing_locations(mod)
+ with self.assertRaises(exc) as cm:
+ compile(mod, "<test>", mode)
+ if msg is not None:
+ self.assertIn(msg, str(cm.exception))
+
+ def expr(self, node, msg=None, *, exc=ValueError):
+ mod = ast.Module([ast.Expr(node)])
+ self.mod(mod, msg, exc=exc)
+
+ def stmt(self, stmt, msg=None):
+ mod = ast.Module([stmt])
+ self.mod(mod, msg)
+
+ def test_module(self):
+ m = ast.Interactive([ast.Expr(ast.Name("x", ast.Store()))])
+ self.mod(m, "must have Load context", "single")
+ m = ast.Expression(ast.Name("x", ast.Store()))
+ self.mod(m, "must have Load context", "eval")
+
+ def _check_arguments(self, fac, check):
+ def arguments(args=None, vararg=None, varargannotation=None,
+ kwonlyargs=None, kwarg=None, kwargannotation=None,
+ defaults=None, kw_defaults=None):
+ if args is None:
+ args = []
+ if kwonlyargs is None:
+ kwonlyargs = []
+ if defaults is None:
+ defaults = []
+ if kw_defaults is None:
+ kw_defaults = []
+ args = ast.arguments(args, vararg, varargannotation, kwonlyargs,
+ kwarg, kwargannotation, defaults, kw_defaults)
+ return fac(args)
+ args = [ast.arg("x", ast.Name("x", ast.Store()))]
+ check(arguments(args=args), "must have Load context")
+ check(arguments(varargannotation=ast.Num(3)),
+ "varargannotation but no vararg")
+ check(arguments(varargannotation=ast.Name("x", ast.Store()), vararg="x"),
+ "must have Load context")
+ check(arguments(kwonlyargs=args), "must have Load context")
+ check(arguments(kwargannotation=ast.Num(42)),
+ "kwargannotation but no kwarg")
+ check(arguments(kwargannotation=ast.Name("x", ast.Store()),
+ kwarg="x"), "must have Load context")
+ check(arguments(defaults=[ast.Num(3)]),
+ "more positional defaults than args")
+ check(arguments(kw_defaults=[ast.Num(4)]),
+ "length of kwonlyargs is not the same as kw_defaults")
+ args = [ast.arg("x", ast.Name("x", ast.Load()))]
+ check(arguments(args=args, defaults=[ast.Name("x", ast.Store())]),
+ "must have Load context")
+ args = [ast.arg("a", ast.Name("x", ast.Load())),
+ ast.arg("b", ast.Name("y", ast.Load()))]
+ check(arguments(kwonlyargs=args,
+ kw_defaults=[None, ast.Name("x", ast.Store())]),
+ "must have Load context")
+
+ def test_funcdef(self):
+ a = ast.arguments([], None, None, [], None, None, [], [])
+ f = ast.FunctionDef("x", a, [], [], None)
+ self.stmt(f, "empty body on FunctionDef")
+ f = ast.FunctionDef("x", a, [ast.Pass()], [ast.Name("x", ast.Store())],
+ None)
+ self.stmt(f, "must have Load context")
+ f = ast.FunctionDef("x", a, [ast.Pass()], [],
+ ast.Name("x", ast.Store()))
+ self.stmt(f, "must have Load context")
+ def fac(args):
+ return ast.FunctionDef("x", args, [ast.Pass()], [], None)
+ self._check_arguments(fac, self.stmt)
+
+ def test_classdef(self):
+ def cls(bases=None, keywords=None, starargs=None, kwargs=None,
+ body=None, decorator_list=None):
+ if bases is None:
+ bases = []
+ if keywords is None:
+ keywords = []
+ if body is None:
+ body = [ast.Pass()]
+ if decorator_list is None:
+ decorator_list = []
+ return ast.ClassDef("myclass", bases, keywords, starargs,
+ kwargs, body, decorator_list)
+ self.stmt(cls(bases=[ast.Name("x", ast.Store())]),
+ "must have Load context")
+ self.stmt(cls(keywords=[ast.keyword("x", ast.Name("x", ast.Store()))]),
+ "must have Load context")
+ self.stmt(cls(starargs=ast.Name("x", ast.Store())),
+ "must have Load context")
+ self.stmt(cls(kwargs=ast.Name("x", ast.Store())),
+ "must have Load context")
+ self.stmt(cls(body=[]), "empty body on ClassDef")
+ self.stmt(cls(body=[None]), "None disallowed")
+ self.stmt(cls(decorator_list=[ast.Name("x", ast.Store())]),
+ "must have Load context")
+
+ def test_delete(self):
+ self.stmt(ast.Delete([]), "empty targets on Delete")
+ self.stmt(ast.Delete([None]), "None disallowed")
+ self.stmt(ast.Delete([ast.Name("x", ast.Load())]),
+ "must have Del context")
+
+ def test_assign(self):
+ self.stmt(ast.Assign([], ast.Num(3)), "empty targets on Assign")
+ self.stmt(ast.Assign([None], ast.Num(3)), "None disallowed")
+ self.stmt(ast.Assign([ast.Name("x", ast.Load())], ast.Num(3)),
+ "must have Store context")
+ self.stmt(ast.Assign([ast.Name("x", ast.Store())],
+ ast.Name("y", ast.Store())),
+ "must have Load context")
+
+ def test_augassign(self):
+ aug = ast.AugAssign(ast.Name("x", ast.Load()), ast.Add(),
+ ast.Name("y", ast.Load()))
+ self.stmt(aug, "must have Store context")
+ aug = ast.AugAssign(ast.Name("x", ast.Store()), ast.Add(),
+ ast.Name("y", ast.Store()))
+ self.stmt(aug, "must have Load context")
+
+ def test_for(self):
+ x = ast.Name("x", ast.Store())
+ y = ast.Name("y", ast.Load())
+ p = ast.Pass()
+ self.stmt(ast.For(x, y, [], []), "empty body on For")
+ self.stmt(ast.For(ast.Name("x", ast.Load()), y, [p], []),
+ "must have Store context")
+ self.stmt(ast.For(x, ast.Name("y", ast.Store()), [p], []),
+ "must have Load context")
+ e = ast.Expr(ast.Name("x", ast.Store()))
+ self.stmt(ast.For(x, y, [e], []), "must have Load context")
+ self.stmt(ast.For(x, y, [p], [e]), "must have Load context")
+
+ def test_while(self):
+ self.stmt(ast.While(ast.Num(3), [], []), "empty body on While")
+ self.stmt(ast.While(ast.Name("x", ast.Store()), [ast.Pass()], []),
+ "must have Load context")
+ self.stmt(ast.While(ast.Num(3), [ast.Pass()],
+ [ast.Expr(ast.Name("x", ast.Store()))]),
+ "must have Load context")
+
+ def test_if(self):
+ self.stmt(ast.If(ast.Num(3), [], []), "empty body on If")
+ i = ast.If(ast.Name("x", ast.Store()), [ast.Pass()], [])
+ self.stmt(i, "must have Load context")
+ i = ast.If(ast.Num(3), [ast.Expr(ast.Name("x", ast.Store()))], [])
+ self.stmt(i, "must have Load context")
+ i = ast.If(ast.Num(3), [ast.Pass()],
+ [ast.Expr(ast.Name("x", ast.Store()))])
+ self.stmt(i, "must have Load context")
+
+ def test_with(self):
+ p = ast.Pass()
+ self.stmt(ast.With([], [p]), "empty items on With")
+ i = ast.withitem(ast.Num(3), None)
+ self.stmt(ast.With([i], []), "empty body on With")
+ i = ast.withitem(ast.Name("x", ast.Store()), None)
+ self.stmt(ast.With([i], [p]), "must have Load context")
+ i = ast.withitem(ast.Num(3), ast.Name("x", ast.Load()))
+ self.stmt(ast.With([i], [p]), "must have Store context")
+
+ def test_raise(self):
+ r = ast.Raise(None, ast.Num(3))
+ self.stmt(r, "Raise with cause but no exception")
+ r = ast.Raise(ast.Name("x", ast.Store()), None)
+ self.stmt(r, "must have Load context")
+ r = ast.Raise(ast.Num(4), ast.Name("x", ast.Store()))
+ self.stmt(r, "must have Load context")
+
+ def test_try(self):
+ p = ast.Pass()
+ t = ast.Try([], [], [], [p])
+ self.stmt(t, "empty body on Try")
+ t = ast.Try([ast.Expr(ast.Name("x", ast.Store()))], [], [], [p])
+ self.stmt(t, "must have Load context")
+ t = ast.Try([p], [], [], [])
+ self.stmt(t, "Try has neither except handlers nor finalbody")
+ t = ast.Try([p], [], [p], [p])
+ self.stmt(t, "Try has orelse but no except handlers")
+ t = ast.Try([p], [ast.ExceptHandler(None, "x", [])], [], [])
+ self.stmt(t, "empty body on ExceptHandler")
+ e = [ast.ExceptHandler(ast.Name("x", ast.Store()), "y", [p])]
+ self.stmt(ast.Try([p], e, [], []), "must have Load context")
+ e = [ast.ExceptHandler(None, "x", [p])]
+ t = ast.Try([p], e, [ast.Expr(ast.Name("x", ast.Store()))], [p])
+ self.stmt(t, "must have Load context")
+ t = ast.Try([p], e, [p], [ast.Expr(ast.Name("x", ast.Store()))])
+ self.stmt(t, "must have Load context")
+
+ def test_assert(self):
+ self.stmt(ast.Assert(ast.Name("x", ast.Store()), None),
+ "must have Load context")
+ assrt = ast.Assert(ast.Name("x", ast.Load()),
+ ast.Name("y", ast.Store()))
+ self.stmt(assrt, "must have Load context")
+
+ def test_import(self):
+ self.stmt(ast.Import([]), "empty names on Import")
+
+ def test_importfrom(self):
+ imp = ast.ImportFrom(None, [ast.alias("x", None)], -42)
+ self.stmt(imp, "level less than -1")
+ self.stmt(ast.ImportFrom(None, [], 0), "empty names on ImportFrom")
+
+ def test_global(self):
+ self.stmt(ast.Global([]), "empty names on Global")
+
+ def test_nonlocal(self):
+ self.stmt(ast.Nonlocal([]), "empty names on Nonlocal")
+
+ def test_expr(self):
+ e = ast.Expr(ast.Name("x", ast.Store()))
+ self.stmt(e, "must have Load context")
+
+ def test_boolop(self):
+ b = ast.BoolOp(ast.And(), [])
+ self.expr(b, "less than 2 values")
+ b = ast.BoolOp(ast.And(), [ast.Num(3)])
+ self.expr(b, "less than 2 values")
+ b = ast.BoolOp(ast.And(), [ast.Num(4), None])
+ self.expr(b, "None disallowed")
+ b = ast.BoolOp(ast.And(), [ast.Num(4), ast.Name("x", ast.Store())])
+ self.expr(b, "must have Load context")
+
+ def test_unaryop(self):
+ u = ast.UnaryOp(ast.Not(), ast.Name("x", ast.Store()))
+ self.expr(u, "must have Load context")
+
+ def test_lambda(self):
+ a = ast.arguments([], None, None, [], None, None, [], [])
+ self.expr(ast.Lambda(a, ast.Name("x", ast.Store())),
+ "must have Load context")
+ def fac(args):
+ return ast.Lambda(args, ast.Name("x", ast.Load()))
+ self._check_arguments(fac, self.expr)
+
+ def test_ifexp(self):
+ l = ast.Name("x", ast.Load())
+ s = ast.Name("y", ast.Store())
+ for args in (s, l, l), (l, s, l), (l, l, s):
+ self.expr(ast.IfExp(*args), "must have Load context")
+
+ def test_dict(self):
+ d = ast.Dict([], [ast.Name("x", ast.Load())])
+ self.expr(d, "same number of keys as values")
+ d = ast.Dict([None], [ast.Name("x", ast.Load())])
+ self.expr(d, "None disallowed")
+ d = ast.Dict([ast.Name("x", ast.Load())], [None])
+ self.expr(d, "None disallowed")
+
+ def test_set(self):
+ self.expr(ast.Set([None]), "None disallowed")
+ s = ast.Set([ast.Name("x", ast.Store())])
+ self.expr(s, "must have Load context")
+
+ def _check_comprehension(self, fac):
+ self.expr(fac([]), "comprehension with no generators")
+ g = ast.comprehension(ast.Name("x", ast.Load()),
+ ast.Name("x", ast.Load()), [])
+ self.expr(fac([g]), "must have Store context")
+ g = ast.comprehension(ast.Name("x", ast.Store()),
+ ast.Name("x", ast.Store()), [])
+ self.expr(fac([g]), "must have Load context")
+ x = ast.Name("x", ast.Store())
+ y = ast.Name("y", ast.Load())
+ g = ast.comprehension(x, y, [None])
+ self.expr(fac([g]), "None disallowed")
+ g = ast.comprehension(x, y, [ast.Name("x", ast.Store())])
+ self.expr(fac([g]), "must have Load context")
+
+ def _simple_comp(self, fac):
+ g = ast.comprehension(ast.Name("x", ast.Store()),
+ ast.Name("x", ast.Load()), [])
+ self.expr(fac(ast.Name("x", ast.Store()), [g]),
+ "must have Load context")
+ def wrap(gens):
+ return fac(ast.Name("x", ast.Store()), gens)
+ self._check_comprehension(wrap)
+
+ def test_listcomp(self):
+ self._simple_comp(ast.ListComp)
+
+ def test_setcomp(self):
+ self._simple_comp(ast.SetComp)
+
+ def test_generatorexp(self):
+ self._simple_comp(ast.GeneratorExp)
+
+ def test_dictcomp(self):
+ g = ast.comprehension(ast.Name("y", ast.Store()),
+ ast.Name("p", ast.Load()), [])
+ c = ast.DictComp(ast.Name("x", ast.Store()),
+ ast.Name("y", ast.Load()), [g])
+ self.expr(c, "must have Load context")
+ c = ast.DictComp(ast.Name("x", ast.Load()),
+ ast.Name("y", ast.Store()), [g])
+ self.expr(c, "must have Load context")
+ def factory(comps):
+ k = ast.Name("x", ast.Load())
+ v = ast.Name("y", ast.Load())
+ return ast.DictComp(k, v, comps)
+ self._check_comprehension(factory)
+
+ def test_yield(self):
+ self.expr(ast.Yield(ast.Name("x", ast.Store())), "must have Load")
+
+ def test_compare(self):
+ left = ast.Name("x", ast.Load())
+ comp = ast.Compare(left, [ast.In()], [])
+ self.expr(comp, "no comparators")
+ comp = ast.Compare(left, [ast.In()], [ast.Num(4), ast.Num(5)])
+ self.expr(comp, "different number of comparators and operands")
+ comp = ast.Compare(ast.Num("blah"), [ast.In()], [left])
+ self.expr(comp, "non-numeric", exc=TypeError)
+ comp = ast.Compare(left, [ast.In()], [ast.Num("blah")])
+ self.expr(comp, "non-numeric", exc=TypeError)
+
+ def test_call(self):
+ func = ast.Name("x", ast.Load())
+ args = [ast.Name("y", ast.Load())]
+ keywords = [ast.keyword("w", ast.Name("z", ast.Load()))]
+ stararg = ast.Name("p", ast.Load())
+ kwarg = ast.Name("q", ast.Load())
+ call = ast.Call(ast.Name("x", ast.Store()), args, keywords, stararg,
+ kwarg)
+ self.expr(call, "must have Load context")
+ call = ast.Call(func, [None], keywords, stararg, kwarg)
+ self.expr(call, "None disallowed")
+ bad_keywords = [ast.keyword("w", ast.Name("z", ast.Store()))]
+ call = ast.Call(func, args, bad_keywords, stararg, kwarg)
+ self.expr(call, "must have Load context")
+ call = ast.Call(func, args, keywords, ast.Name("z", ast.Store()), kwarg)
+ self.expr(call, "must have Load context")
+ call = ast.Call(func, args, keywords, stararg,
+ ast.Name("w", ast.Store()))
+ self.expr(call, "must have Load context")
+
+ def test_num(self):
+ class subint(int):
+ pass
+ class subfloat(float):
+ pass
+ class subcomplex(complex):
+ pass
+ for obj in "0", "hello", subint(), subfloat(), subcomplex():
+ self.expr(ast.Num(obj), "non-numeric", exc=TypeError)
+
+ def test_attribute(self):
+ attr = ast.Attribute(ast.Name("x", ast.Store()), "y", ast.Load())
+ self.expr(attr, "must have Load context")
+
+ def test_subscript(self):
+ sub = ast.Subscript(ast.Name("x", ast.Store()), ast.Index(ast.Num(3)),
+ ast.Load())
+ self.expr(sub, "must have Load context")
+ x = ast.Name("x", ast.Load())
+ sub = ast.Subscript(x, ast.Index(ast.Name("y", ast.Store())),
+ ast.Load())
+ self.expr(sub, "must have Load context")
+ s = ast.Name("x", ast.Store())
+ for args in (s, None, None), (None, s, None), (None, None, s):
+ sl = ast.Slice(*args)
+ self.expr(ast.Subscript(x, sl, ast.Load()),
+ "must have Load context")
+ sl = ast.ExtSlice([])
+ self.expr(ast.Subscript(x, sl, ast.Load()), "empty dims on ExtSlice")
+ sl = ast.ExtSlice([ast.Index(s)])
+ self.expr(ast.Subscript(x, sl, ast.Load()), "must have Load context")
+
+ def test_starred(self):
+ left = ast.List([ast.Starred(ast.Name("x", ast.Load()), ast.Store())],
+ ast.Store())
+ assign = ast.Assign([left], ast.Num(4))
+ self.stmt(assign, "must have Store context")
+
+ def _sequence(self, fac):
+ self.expr(fac([None], ast.Load()), "None disallowed")
+ self.expr(fac([ast.Name("x", ast.Store())], ast.Load()),
+ "must have Load context")
+
+ def test_list(self):
+ self._sequence(ast.List)
+
+ def test_tuple(self):
+ self._sequence(ast.Tuple)
+
+ def test_stdlib_validates(self):
+ stdlib = os.path.dirname(ast.__file__)
+ tests = [fn for fn in os.listdir(stdlib) if fn.endswith(".py")]
+ tests.extend(["test/test_grammar.py", "test/test_unpack_ex.py"])
+ for module in tests:
+ fn = os.path.join(stdlib, module)
+ with open(fn, "r", encoding="utf-8") as fp:
+ source = fp.read()
+ mod = ast.parse(source)
+ compile(mod, fn, "exec")
+
+
def test_main():
- support.run_unittest(AST_Tests, ASTHelpers_Test)
+ support.run_unittest(AST_Tests, ASTHelpers_Test, ASTValidatorTests)
def main():
if __name__ != '__main__':