Python: Modernise the py/explicit-return-in-init query.

RasmusWL · RasmusWL · commit 6e50a0ef84ee · 2019-09-23T11:22:55.000+02:00
Add explicit test case to show that we don't doulbe report this problem.
diff --git a/python/ql/src/Functions/ExplicitReturnInInit.ql b/python/ql/src/Functions/ExplicitReturnInInit.ql
@@ -13,11 +13,10 @@
 import python
 
 from Return r
-where exists(Function init | init.isInitMethod() and
-r.getScope() = init and exists(r.getValue())) and
-not r.getValue() instanceof None and
-not exists(FunctionObject f | f.getACall() = r.getValue().getAFlowNode() |
-    f.neverReturns()
-) and
-not exists(Attribute meth | meth = ((Call)r.getValue()).getFunc() | meth.getName() = "__init__")
+where
+    exists(Function init | init.isInitMethod() and r.getScope() = init and exists(r.getValue())) and
+    not r.getValue() instanceof None and
+    not exists(FunctionValue f | f.getACall() = r.getValue().getAFlowNode() | f.neverReturns()) and
+    // to avoid double reporting, don't trigger if returning result from other __init__ function
+    not exists(Attribute meth | meth = r.getValue().(Call).getFunc() | meth.getName() = "__init__")
 select r, "Explicit return in __init__ method."
diff --git a/python/ql/test/query-tests/Functions/general/explicit_return_in_init.py b/python/ql/test/query-tests/Functions/general/explicit_return_in_init.py
@@ -37,3 +37,9 @@ class InitCallsInit(InitCallsError):
 
     def __init__(self):
         return super(InitCallsInit, self).__init__()
+
+# This is not ok, but we will only report root cause (ExplicitReturnInInit)
+class InitCallsBadInit(ExplicitReturnInInit):
+
+    def __init__(self):
+        return ExplicitReturnInInit.__init__(self)
