gh-101758: Clean Up Uses of Import State (gh-101919)

This change is almost entirely moving code around and hiding import state behind internal API.  We introduce no changes to behavior, nor to non-internal API.  (Since there was already going to be a lot of churn, I took this as an opportunity to re-organize import.c into topically-grouped sections of code.)  The motivation is to simplify a number of upcoming changes.

Specific changes:

* move existing import-related code to import.c, wherever possible
* add internal API for interacting with import state (both global and per-interpreter)
* use only API outside of import.c (to limit churn there when changing the location, etc.)
* consolidate the import-related state of PyInterpreterState into a single struct field (this changes layout slightly)
* add macros for import state in import.c (to simplify changing the location)
* group code in import.c into sections
*remove _PyState_AddModule()

https://github.com/python/cpython/issues/101758

1 files changed, 2 insertions, 9 deletions

diff --git a/Python/_warnings.c b/Python/_warnings.c
index e78f216..d510381 100644
--- a/Python/_warnings.c
+++ b/Python/_warnings.c
@@ -214,7 +214,7 @@ get_warnings_attr(PyInterpreterState *interp, PyObject *attr, int try_import)
            gone, then we can't even use PyImport_GetModule without triggering
            an interpreter abort.
         */
-        if (!interp->modules) {
+        if (!_PyImport_GetModules(interp)) {
             return NULL;
         }
         warnings_module = PyImport_GetModule(&_Py_ID(warnings));
@@ -1050,7 +1050,6 @@ warnings_warn_impl(PyObject *module, PyObject *message, PyObject *category,
 static PyObject *
 get_source_line(PyInterpreterState *interp, PyObject *module_globals, int lineno)
 {
-    PyObject *external;
     PyObject *loader;
     PyObject *module_name;
     PyObject *get_source;
@@ -1059,13 +1058,7 @@ get_source_line(PyInterpreterState *interp, PyObject *module_globals, int lineno
     PyObject *source_line;
 
     /* stolen from import.c */
-    external = PyObject_GetAttrString(interp->importlib, "_bootstrap_external");
-    if (external == NULL) {
-        return NULL;
-    }
-
-    loader = PyObject_CallMethod(external, "_bless_my_loader", "O", module_globals, NULL);
-    Py_DECREF(external);
+    loader = _PyImport_BlessMyLoader(interp, module_globals);
     if (loader == NULL) {
         return NULL;
     }