https://github.com/python/cpython/commit/0f161b307969f86b4f8f31baf38f53f5462... commit: 0f161b307969f86b4f8f31baf38f53f5462a9874 branch: 3.7 author: Miss Islington (bot) <31488909+miss-islington@users.noreply.github.com> committer: GitHub <noreply@github.com> date: 2018-09-30T11:19:15-07:00 summary: bpo-34854: Fix compiling string annotations containing lambdas. (GH-9645) * Compiling a string annotation containing a lambda with keyword-only argument without default value caused a crash. * Remove the final "*" (it is incorrect syntax) in the representation of lambda without *args and keyword-only arguments when compile from AST. * Improve the representation of lambda without arguments. (cherry picked from commit 2a2940e5c3e6d92f4fac5e9d361a1e224bb2f12e) Co-authored-by: Serhiy Storchaka <storchaka@gmail.com> files: A Misc/NEWS.d/next/Core and Builtins/2018-09-30-19-27-13.bpo-34854.6TKTcB.rst M Lib/test/test_future.py M Python/ast_unparse.c diff --git a/Lib/test/test_future.py b/Lib/test/test_future.py index 61cd63479d85..70da0cf57040 100644 --- a/Lib/test/test_future.py +++ b/Lib/test/test_future.py @@ -178,11 +178,12 @@ def test_annotations(self): eq('-1') eq('~int and not v1 ^ 123 + v2 | True') eq('a + (not b)') + eq('lambda: None') eq('lambda arg: None') eq('lambda a=True: a') eq('lambda a, b, c=True: a') eq("lambda a, b, c=True, *, d=1 << v2, e='str': a") - eq("lambda a, b, c=True, *vararg, d=v1 << 2, e='str', **kwargs: a + b") + eq("lambda a, b, c=True, *vararg, d, e='str', **kwargs: a + b") eq('lambda x: lambda y: x + y') eq('1 if True else 2') eq('str or None if int or True else str or bytes or None') diff --git a/Misc/NEWS.d/next/Core and Builtins/2018-09-30-19-27-13.bpo-34854.6TKTcB.rst b/Misc/NEWS.d/next/Core and Builtins/2018-09-30-19-27-13.bpo-34854.6TKTcB.rst new file mode 100644 index 000000000000..4e04e1f157cd --- /dev/null +++ b/Misc/NEWS.d/next/Core and Builtins/2018-09-30-19-27-13.bpo-34854.6TKTcB.rst @@ -0,0 +1,2 @@ +Fixed a crash in compiling string annotations containing a lambda with a +keyword-only argument that doesn't have a default value. diff --git a/Python/ast_unparse.c b/Python/ast_unparse.c index 725ce31fe3c0..43453f567b05 100644 --- a/Python/ast_unparse.c +++ b/Python/ast_unparse.c @@ -212,7 +212,7 @@ append_ast_args(_PyUnicodeWriter *writer, arguments_ty args) } /* vararg, or bare '*' if no varargs but keyword-only arguments present */ - if (args->vararg || args->kwonlyargs) { + if (args->vararg || asdl_seq_LEN(args->kwonlyargs)) { APPEND_STR_IF_NOT_FIRST(", "); APPEND_STR("*"); if (args->vararg) { @@ -229,8 +229,11 @@ append_ast_args(_PyUnicodeWriter *writer, arguments_ty args) di = i - arg_count + default_count; if (di >= 0) { - APPEND_STR("="); - APPEND_EXPR((expr_ty)asdl_seq_GET(args->kw_defaults, di), PR_TEST); + expr_ty default_ = (expr_ty)asdl_seq_GET(args->kw_defaults, di); + if (default_) { + APPEND_STR("="); + APPEND_EXPR(default_, PR_TEST); + } } } @@ -248,7 +251,7 @@ static int append_ast_lambda(_PyUnicodeWriter *writer, expr_ty e, int level) { APPEND_STR_IF(level > PR_TEST, "("); - APPEND_STR("lambda "); + APPEND_STR(asdl_seq_LEN(e->v.Lambda.args->args) ? "lambda " : "lambda"); APPEND(args, e->v.Lambda.args); APPEND_STR(": "); APPEND_EXPR(e->v.Lambda.body, PR_TEST);