Allow NamedLoaderContexts to be returned from loader

It is useful in some cases to return NamedLoaderContexts from loaded
functions. Instead of choking or requireing implimenters to call the
context's value() method before being de-scoped, detect when a
NamedLoaderContext has been returned and return the value from the
current context.

salt/loader/lazy.py

@@ -1246,7 +1246,10 @@ def _run_as(self, _func_or_method, *args, **kwargs):
             self.parent_loader = current_loader
         token = salt.loader.context.loader_ctxvar.set(self)
         try:
-            return _func_or_method(*args, **kwargs)
+            ret = _func_or_method(*args, **kwargs)
+            if isinstance(ret, salt.loader.context.NamedLoaderContext):
+                ret = ret.value()
+            return ret
         finally:
             self.parent_loader = None
             salt.loader.context.loader_ctxvar.reset(token)

tests/pytests/integration/modules/test_config.py

@@ -0,0 +1,8 @@
+import pytest
+
+
+@pytest.mark.slow_test
+def test_config_items(salt_cli, salt_minion):
+    ret = salt_cli.run("config.items", minion_tgt=salt_minion.id)
+    assert ret.returncode == 0
+    assert isinstance(ret.data, dict)

tests/pytests/unit/loader/test_loader.py

@@ -62,3 +62,16 @@ def test_raw_mod_functions():
     ret = salt.loader.raw_mod(opts, "grains", "get")
     for k, v in ret.items():
         assert isinstance(v, salt.loader.lazy.LoadedFunc)
+
+
+def test_return_named_context_from_loaded_func(tmp_path):
+    opts = {
+        "optimization_order": [0],
+    }
+    contents = """
+    def foobar():
+        return __test__
+    """
+    with pytest.helpers.temp_file("mymod.py", contents, directory=tmp_path):
+        loader = salt.loader.LazyLoader([tmp_path], opts, pack={"__test__": "meh"})
+        assert loader["mymod.foobar"]() == "meh"