Allow subclassing with extra args.

ionelmc · Oct 23, 2018 · d9a4898 · d9a4898
1 parent 2052fce
commit d9a4898
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Showing 2 changed files with 16 additions and 2 deletions.
diff --git a/src/stampede/worker.py b/src/stampede/worker.py
@@ -42,13 +42,13 @@ def __str__(self):
 class SingleInstanceMeta(type):
     __inst = None
 
-    def __call__(cls, path):
+    def __call__(cls, path, *args, **kwargs):
         if cls.__inst is not None:
             raise RuntimeError("Only 1 instance allowed!")
 
         lock = FileLock(path)
         if lock.acquire():
-            inst = cls.__inst = super(SingleInstanceMeta, cls).__call__(path)
+            inst = cls.__inst = super(SingleInstanceMeta, cls).__call__(path, *args, **kwargs)
             return inst
         else:
             return StampedeStub()

diff --git a/tests/test_worker.py b/tests/test_worker.py
@@ -178,6 +178,20 @@ def test_empty_request():
 
 def test_double_instance():
     from stampede import StampedeWorker
+    StampedeWorker.__SingleInstanceMeta_inst = None
     StampedeWorker(helper.PATH)
     with pytest.raises(RuntimeError):
         StampedeWorker(helper.PATH)
+
+
+def test_subclassing():
+    from stampede import StampedeWorker
+
+    class MyWorker(StampedeWorker):
+        def __init__(self, path, config):
+            super(MyWorker, self).__init__(path)
+            self.config = config
+
+    MyWorker.__SingleInstanceMeta_inst = None
+    worker = MyWorker(helper.PATH, 'foobar')
+    assert worker.config == 'foobar'