From 82d1fadebb6eafca23cf979f9fe7bf6e60ad9b7f Mon Sep 17 00:00:00 2001
From: MWR27 <64335495+MWR27@users.noreply.github.com>
Date: Wed, 3 Jun 2026 12:32:11 -0400
Subject: [PATCH 1/2] Add warning for implicit relative imports

---
 Python/import.c | 41 +++++++++++++++++++++++++++++++++++++++++
 1 file changed, 41 insertions(+)

diff --git a/Python/import.c b/Python/import.c
index b79354b37a4064..1262a1c2b6c9f4 100644
--- a/Python/import.c
+++ b/Python/import.c
@@ -2247,6 +2247,11 @@ import_module_level(char *name, PyObject *globals, PyObject *locals,
     Py_ssize_t buflen = 0;
     PyObject *parent, *head, *next, *tail;
 
+    char parentstr[MAXPATHLEN + 1]; /* maybe rename to pkgstr or pkgname? */
+    char *orig_name = name;
+    int is_from_form;
+    int might_warn_implicit;
+
     if (strchr(name, '/') != NULL
 #ifdef MS_WINDOWS
         || strchr(name, '\\') != NULL
@@ -2265,6 +2270,13 @@ import_module_level(char *name, PyObject *globals, PyObject *locals,
     if (parent == NULL)
         goto error_exit;
 
+    might_warn_implicit = level < 0 &&
+                          parent != Py_None &&
+                          buflen + strlen(name) + 1 <= MAXPATHLEN;
+    if (might_warn_implicit) {
+        memcpy(parentstr, buf, buflen + 1);
+    }
+
     Py_INCREF(parent);
     head = load_next(parent, level < 0 ? Py_None : parent, &name, buf,
                         &buflen);
@@ -2303,6 +2315,35 @@ import_module_level(char *name, PyObject *globals, PyObject *locals,
         }
         if (!b)
             fromlist = NULL;
+        is_from_form = b;
+    }
+
+    if (might_warn_implicit) {
+        char potential_resolved[MAXPATHLEN + 2];
+        sprintf(potential_resolved, "%s.%s", parentstr, orig_name);
+
+        if (strcmp(potential_resolved, buf) == 0) {
+            char msg[524];
+            char fix[260];
+            if (is_from_form) {
+                sprintf(msg,
+                    "implicit relative import from '%.200s' resolved to '%.200s'; "
+                    "in 3.x imports are absolute by default, so this may resolve differently",
+                    orig_name, buf);
+                sprintf(fix,
+                    "use 'from %.200s import ...' if the parent package is intended", buf);
+            } else {
+                sprintf(msg,
+                    "implicit relative import '%.200s' resolved to '%.200s'; "
+                    "in 3.x imports are absolute by default, so this may resolve differently",
+                    orig_name, buf);
+                sprintf(fix,
+                    "use 'import %.200s' if the parent package is intended", buf);
+            }
+            if (PyErr_WarnPy3k_WithFix(msg, fix, 1) < 0) {
+                goto error_exit;
+            }
+        }
     }
 
     if (fromlist == NULL) {

From 411eee548d121bb82476decd8377c33ad1f16fff Mon Sep 17 00:00:00 2001
From: MWR27 <64335495+MWR27@users.noreply.github.com>
Date: Wed, 3 Jun 2026 13:09:33 -0400
Subject: [PATCH 2/2] Fix not recognizing submodules in multiple levels of
 subpackages

---
 Python/import.c | 1 +
 1 file changed, 1 insertion(+)

diff --git a/Python/import.c b/Python/import.c
index 1262a1c2b6c9f4..9b8759164d00cb 100644
--- a/Python/import.c
+++ b/Python/import.c
@@ -2272,6 +2272,7 @@ import_module_level(char *name, PyObject *globals, PyObject *locals,
 
     might_warn_implicit = level < 0 &&
                           parent != Py_None &&
+                          strchr(name, '.') == NULL &&
                           buflen + strlen(name) + 1 <= MAXPATHLEN;
     if (might_warn_implicit) {
         memcpy(parentstr, buf, buflen + 1);