bpo-40334: Use old compiler when compile mode is func_type (GH-19692)

gvanrossum · web-flow · commit bc28805570ae · 2020-04-23T15:42:56.000-07:00
This is invoked by mypy, using ast.parse(source, "<func_type>", "func_type"). Since the new grammar doesn't yet support the func_type_input start symbol we must use the old compiler in this case to prevent a crash. https://bugs.python.org/issue40334
diff --git a/Python/bltinmodule.c b/Python/bltinmodule.c
@@ -817,7 +817,7 @@ builtin_compile_impl(PyObject *module, PyObject *source, PyObject *filename,
         goto error;
 
     int current_use_peg = PyInterpreterState_Get()->config._use_peg_parser;
-    if (flags & PyCF_TYPE_COMMENTS || feature_version >= 0) {
+    if (flags & PyCF_TYPE_COMMENTS || feature_version >= 0 || compile_mode == 3) {
         PyInterpreterState_Get()->config._use_peg_parser = 0;
     }
     result = Py_CompileStringObject(str, filename, start[compile_mode], &cf, optimize);

Original file line number	Diff line number	Diff line change
`@@ -817,7 +817,7 @@ builtin_compile_impl(PyObject module, PyObject source, PyObject *filename,`
`817`	`817`	`goto error;`
`818`	`818`
`819`	`819`	`int current_use_peg = PyInterpreterState_Get()->config._use_peg_parser;`
`820`		`- if (flags & PyCF_TYPE_COMMENTS \|\| feature_version >= 0) {`
	`820`	`+ if (flags & PyCF_TYPE_COMMENTS \|\| feature_version >= 0 \|\| compile_mode == 3) {`
`821`	`821`	`PyInterpreterState_Get()->config._use_peg_parser = 0;`
`822`	`822`	`}`
`823`	`823`	`result = Py_CompileStringObject(str, filename, start[compile_mode], &cf, optimize);`