[Python-checkins] bpo-36332: Allow compile() to handle AST objects with assignment expressions (GH-12398)

Mon Mar 18 09:51:59 EDT 2019

https://github.com/python/cpython/commit/0c9258a6d299e0484538ef8d4b23f30515283db2
commit: 0c9258a6d299e0484538ef8d4b23f30515283db2
branch: master
author: Pablo Galindo <Pablogsal at gmail.com>
committer: GitHub <noreply at github.com>
date: 2019年03月18日T13:51:53Z
summary:
bpo-36332: Allow compile() to handle AST objects with assignment expressions (GH-12398)
files:
A Misc/NEWS.d/next/Core and Builtins/2019-03-18-09-27-54.bpo-36332.yEC-Vz.rst
M Lib/test/test_ast.py
M Python/ast.c

diff --git a/Lib/test/test_ast.py b/Lib/test/test_ast.py
index a7ee0da38d48..e39d1f2e17a8 100644
--- a/Lib/test/test_ast.py
+++ b/Lib/test/test_ast.py
@@ -135,6 +135,9 @@ def to_tuple(t):
 "@deco1\n at deco2()\nclass C: pass",
 # Decorator with generator argument
 "@deco(a for a in b)\ndef f(): pass",
+ # Simple assignment expression
+ "(a := 1)",
+
 ]
 
 # These are compiled through "single"
@@ -276,6 +279,13 @@ def test_snippets(self):
 with self.subTest(action="compiling", input=i, kind=kind):
 compile(ast_tree, "?", kind)
 
+ def test_ast_validation(self):
+ # compile() is the only function that calls PyAST_Validate
+ snippets_to_validate = exec_tests + single_tests + eval_tests
+ for snippet in snippets_to_validate:
+ tree = ast.parse(snippet)
+ compile(tree, '<string>', 'exec')
+
 def test_slice(self):
 slc = ast.parse("x[::]").body[0].value.slice
 self.assertIsNone(slc.upper)
@@ -1677,6 +1687,7 @@ def main():
 ('Module', [('AsyncFunctionDef', (3, 0), 'f', ('arguments', [], None, [], [], None, []), [('Pass', (3, 15))], [('Name', (1, 1), 'deco1', ('Load',)), ('Call', (2, 0), ('Name', (2, 1), 'deco2', ('Load',)), [], [])], None, None)], []),
 ('Module', [('ClassDef', (3, 0), 'C', [], [], [('Pass', (3, 9))], [('Name', (1, 1), 'deco1', ('Load',)), ('Call', (2, 0), ('Name', (2, 1), 'deco2', ('Load',)), [], [])])], []),
 ('Module', [('FunctionDef', (2, 0), 'f', ('arguments', [], None, [], [], None, []), [('Pass', (2, 9))], [('Call', (1, 1), ('Name', (1, 1), 'deco', ('Load',)), [('GeneratorExp', (1, 5), ('Name', (1, 6), 'a', ('Load',)), [('comprehension', ('Name', (1, 12), 'a', ('Store',)), ('Name', (1, 17), 'b', ('Load',)), [], 0)])], [])], None, None)], []),
+('Module', [('Expr', (1, 0), ('NamedExpr', (1, 1), ('Name', (1, 1), 'a', ('Store',)), ('Constant', (1, 6), 1, None)))], []),
 ]
 single_results = [
 ('Interactive', [('Expr', (1, 0), ('BinOp', (1, 0), ('Constant', (1, 0), 1, None), ('Add',), ('Constant', (1, 2), 2, None)))]),
diff --git a/Misc/NEWS.d/next/Core and Builtins/2019-03-18-09-27-54.bpo-36332.yEC-Vz.rst b/Misc/NEWS.d/next/Core and Builtins/2019-03-18-09-27-54.bpo-36332.yEC-Vz.rst
new file mode 100644
index 000000000000..2c69c1c56527
--- /dev/null
+++ b/Misc/NEWS.d/next/Core and Builtins/2019-03-18-09-27-54.bpo-36332.yEC-Vz.rst	
@@ -0,0 +1,2 @@
+The builtin :func:`compile` can now handle AST objects that contain
+assignment expressions. Patch by Pablo Galindo.
diff --git a/Python/ast.c b/Python/ast.c
index 971b8ddc8c24..e9154fecff06 100644
--- a/Python/ast.c
+++ b/Python/ast.c
@@ -316,13 +316,14 @@ validate_expr(expr_ty exp, expr_context_ty ctx)
 return validate_exprs(exp->v.List.elts, ctx, 0);
 case Tuple_kind:
 return validate_exprs(exp->v.Tuple.elts, ctx, 0);
+ case NamedExpr_kind:
+ return validate_expr(exp->v.NamedExpr.value, Load);
 /* This last case doesn't have any checking. */
 case Name_kind:
 return 1;
- default:
- PyErr_SetString(PyExc_SystemError, "unexpected expression");
- return 0;
 }
+ PyErr_SetString(PyExc_SystemError, "unexpected expression");
+ return 0;
 }
 
 static int
