bpo-37001: Makes symtable.symtable have parity with compile for input (#13483)

* Makes symtable.symtable have parity for accepted datatypes
for source code as compile()

* Add NEWS blurb

2 files changed, 63 insertions, 56 deletions

diff --git a/Python/bltinmodule.c b/Python/bltinmodule.c
index 5d58085..065ad95 100644
--- a/Python/bltinmodule.c
+++ b/Python/bltinmodule.c
@@ -687,55 +687,6 @@ builtin_chr_impl(PyObject *module, int i)
 }
 
 
-static const char *
-source_as_string(PyObject *cmd, const char *funcname, const char *what, PyCompilerFlags *cf, PyObject **cmd_copy)
-{
-    const char *str;
-    Py_ssize_t size;
-    Py_buffer view;
-
-    *cmd_copy = NULL;
-    if (PyUnicode_Check(cmd)) {
-        cf->cf_flags |= PyCF_IGNORE_COOKIE;
-        str = PyUnicode_AsUTF8AndSize(cmd, &size);
-        if (str == NULL)
-            return NULL;
-    }
-    else if (PyBytes_Check(cmd)) {
-        str = PyBytes_AS_STRING(cmd);
-        size = PyBytes_GET_SIZE(cmd);
-    }
-    else if (PyByteArray_Check(cmd)) {
-        str = PyByteArray_AS_STRING(cmd);
-        size = PyByteArray_GET_SIZE(cmd);
-    }
-    else if (PyObject_GetBuffer(cmd, &view, PyBUF_SIMPLE) == 0) {
-        /* Copy to NUL-terminated buffer. */
-        *cmd_copy = PyBytes_FromStringAndSize(
-            (const char *)view.buf, view.len);
-        PyBuffer_Release(&view);
-        if (*cmd_copy == NULL) {
-            return NULL;
-        }
-        str = PyBytes_AS_STRING(*cmd_copy);
-        size = PyBytes_GET_SIZE(*cmd_copy);
-    }
-    else {
-        PyErr_Format(PyExc_TypeError,
-          "%s() arg 1 must be a %s object",
-          funcname, what);
-        return NULL;
-    }
-
-    if (strlen(str) != (size_t)size) {
-        PyErr_SetString(PyExc_ValueError,
-                        "source code string cannot contain null bytes");
-        Py_CLEAR(*cmd_copy);
-        return NULL;
-    }
-    return str;
-}
-
 /*[clinic input]
 compile as builtin_compile
 
@@ -855,7 +806,7 @@ builtin_compile_impl(PyObject *module, PyObject *source, PyObject *filename,
         goto finally;
     }
 
-    str = source_as_string(source, "compile", "string, bytes or AST", &cf, &source_copy);
+    str = _Py_SourceAsString(source, "compile", "string, bytes or AST", &cf, &source_copy);
     if (str == NULL)
         goto error;
 
@@ -991,7 +942,7 @@ builtin_eval_impl(PyObject *module, PyObject *source, PyObject *globals,
 
     cf.cf_flags = PyCF_SOURCE_IS_UTF8;
     cf.cf_feature_version = PY_MINOR_VERSION;
-    str = source_as_string(source, "eval", "string, bytes or code", &cf, &source_copy);
+    str = _Py_SourceAsString(source, "eval", "string, bytes or code", &cf, &source_copy);
     if (str == NULL)
         return NULL;
 
@@ -1083,7 +1034,7 @@ builtin_exec_impl(PyObject *module, PyObject *source, PyObject *globals,
         PyCompilerFlags cf;
         cf.cf_flags = PyCF_SOURCE_IS_UTF8;
         cf.cf_feature_version = PY_MINOR_VERSION;
-        str = source_as_string(source, "exec",
+        str = _Py_SourceAsString(source, "exec",
                                        "string, bytes or code", &cf,
                                        &source_copy);
         if (str == NULL)
diff --git a/Python/pythonrun.c b/Python/pythonrun.c
index ace9f2f..784c15b 100644
--- a/Python/pythonrun.c
+++ b/Python/pythonrun.c
@@ -1231,21 +1231,77 @@ PyCompileString(const char *str, const char *filename, int start)
     return Py_CompileStringFlags(str, filename, start, NULL);
 }
 
+const char *
+_Py_SourceAsString(PyObject *cmd, const char *funcname, const char *what, PyCompilerFlags *cf, PyObject **cmd_copy)
+{
+    const char *str;
+    Py_ssize_t size;
+    Py_buffer view;
+
+    *cmd_copy = NULL;
+    if (PyUnicode_Check(cmd)) {
+        cf->cf_flags |= PyCF_IGNORE_COOKIE;
+        str = PyUnicode_AsUTF8AndSize(cmd, &size);
+        if (str == NULL)
+            return NULL;
+    }
+    else if (PyBytes_Check(cmd)) {
+        str = PyBytes_AS_STRING(cmd);
+        size = PyBytes_GET_SIZE(cmd);
+    }
+    else if (PyByteArray_Check(cmd)) {
+        str = PyByteArray_AS_STRING(cmd);
+        size = PyByteArray_GET_SIZE(cmd);
+    }
+    else if (PyObject_GetBuffer(cmd, &view, PyBUF_SIMPLE) == 0) {
+        /* Copy to NUL-terminated buffer. */
+        *cmd_copy = PyBytes_FromStringAndSize(
+            (const char *)view.buf, view.len);
+        PyBuffer_Release(&view);
+        if (*cmd_copy == NULL) {
+            return NULL;
+        }
+        str = PyBytes_AS_STRING(*cmd_copy);
+        size = PyBytes_GET_SIZE(*cmd_copy);
+    }
+    else {
+        PyErr_Format(PyExc_TypeError,
+            "%s() arg 1 must be a %s object",
+            funcname, what);
+        return NULL;
+    }
+
+    if (strlen(str) != (size_t)size) {
+        PyErr_SetString(PyExc_ValueError,
+            "source code string cannot contain null bytes");
+        Py_CLEAR(*cmd_copy);
+        return NULL;
+    }
+    return str;
+}
+
 struct symtable *
 Py_SymtableStringObject(const char *str, PyObject *filename, int start)
 {
+    PyCompilerFlags flags;
+
+    flags.cf_flags = 0;
+    flags.cf_feature_version = PY_MINOR_VERSION;
+    return _Py_SymtableStringObjectFlags(str, filename, start, &flags);
+}
+
+struct symtable *
+_Py_SymtableStringObjectFlags(const char *str, PyObject *filename, int start, PyCompilerFlags *flags)
+{
     struct symtable *st;
     mod_ty mod;
-    PyCompilerFlags flags;
     PyArena *arena;
 
     arena = PyArena_New();
     if (arena == NULL)
         return NULL;
 
-    flags.cf_flags = 0;
-    flags.cf_feature_version = PY_MINOR_VERSION;
-    mod = PyParser_ASTFromStringObject(str, filename, start, &flags, arena);
+    mod = PyParser_ASTFromStringObject(str, filename, start, flags, arena);
     if (mod == NULL) {
         PyArena_Free(arena);
         return NULL;