py/builtinimport: Allow builtin modules to be packages.

jimmo · jimmo · commit d91abfb9bc78 · 2023-05-11T13:43:40.000+10:00
To use this, a built-in can add a submodule as a member of its globals
dict.

The submodule should call itself foo.bar, but this is not strictly
necessary, and requires using qstrdefs(port).h to make the qstr.

Signed-off-by: Jim Mussared &lt;jim.mussared@gmail.com&gt;
diff --git a/py/builtinimport.c b/py/builtinimport.c
@@ -414,6 +414,20 @@ STATIC mp_obj_t process_import_at_level(qstr full_mod_name, qstr level_mod_name,
     } else {
         DEBUG_printf("Searching for sub-module\n");
 
+        #if MICROPY_MODULE_BUILTIN_SUBPACKAGES
+        // If the outer module is a builtin (because its map is in ROM), then
+        // treat it like a package if it contains this submodule in its
+        // globals dict.
+        mp_obj_module_t *mod = MP_OBJ_TO_PTR(outer_module_obj);
+        if (mod->globals->map.is_fixed) {
+            elem = mp_map_lookup(&mod->globals->map, MP_OBJ_NEW_QSTR(level_mod_name), MP_MAP_LOOKUP);
+            // Also verify that the entry in the globals dict is in fact a module.
+            if (elem && mp_obj_is_type(elem->value, &mp_type_module)) {
+                return elem->value;
+            }
+        }
+        #endif
+
         // If the outer module is a package, it will have __path__ set.
         // We can use that as the path to search inside.
         mp_obj_t dest[2];
diff --git a/py/mpconfig.h b/py/mpconfig.h
@@ -850,6 +850,13 @@ typedef double mp_float_t;
 #define MICROPY_MODULE_BUILTIN_INIT (MICROPY_CONFIG_ROM_LEVEL_AT_LEAST_EXTRA_FEATURES)
 #endif
 
+// Whether to allow built-in modules to have sub-packages (by making the
+// sub-package a member of their locals dict). The sub-package __name__ must
+// be foo.bar, and only top-level modules may have __init__.
+#ifndef MICROPY_MODULE_BUILTIN_SUBPACKAGES
+#define MICROPY_MODULE_BUILTIN_SUBPACKAGES (MICROPY_CONFIG_ROM_LEVEL_AT_LEAST_EVERYTHING)
+#endif
+
 // Whether to support module-level __getattr__ (see PEP 562)
 #ifndef MICROPY_MODULE_GETATTR
 #define MICROPY_MODULE_GETATTR (MICROPY_CONFIG_ROM_LEVEL_AT_LEAST_CORE_FEATURES)
