Better support for starred destructuring

Previously, x, *y = z was not adding y in the locals / globals

beniget/beniget.py

@@ -1145,7 +1145,13 @@ def visit_Subscript(self, node):
         self.visit(node.slice).add_user(dnode)
         return dnode
 
-    visit_Starred = visit_Await
+    def visit_Starred(self, node):
+        if isinstance(node.ctx, ast.Store):
+            return self.visit(node.value)
+        else:
+            dnode = self.chains.setdefault(node, Def(node))
+            self.visit(node.value).add_user(dnode)
+            return dnode
 
     def visit_NamedExpr(self, node):
         dnode = self.chains.setdefault(node, Def(node))
@@ -1195,7 +1201,7 @@ def visit_Destructured(self, node):
                 tmp_store, elt.ctx = elt.ctx, tmp_store
                 self.visit(elt)
                 tmp_store, elt.ctx = elt.ctx, tmp_store
-            elif isinstance(elt, ast.Subscript):
+            elif isinstance(elt, (ast.Subscript, ast.Starred)):
                 self.visit(elt)
             elif isinstance(elt, (ast.List, ast.Tuple)):
                 self.visit_Destructured(elt)

tests/test_chains.py

@@ -75,6 +75,11 @@ def test_type_destructuring_for(self):
         code = "for a, b in ((1,2), (3,4)): a"
         self.checkChains(code, ["a -> (a -> ())", "b -> ()"])
 
+    if sys.version_info.major >= 3:
+        def test_type_destructuring_starred(self):
+            code = "a, *b = range(2); b"
+            self.checkChains(code, ['a -> ()', 'b -> (b -> ())'])
+
     def test_assign_in_loop(self):
         code = "a = 2\nwhile 1: a = 1\na"
         self.checkChains(code, ["a -> (a -> ())", "a -> (a -> ())"])

tests/test_definitions.py

@@ -89,6 +89,11 @@ def testGlobalDestructuring(self):
         code = "x, y = 1, 2"
         self.checkGlobals(code, ["x", "y"])
 
+    if sys.version_info.major >= 3:
+        def testGlobalStarredDestructuring(self):
+            code = "x, *y = 1, [2]"
+            self.checkGlobals(code, ["x", "y"])
+
     def testGlobalAugAssign(self):
         code = "x = 1; x += 2"
         self.checkGlobals(code, ["x"])
@@ -369,6 +374,10 @@ def test_LocalNonLocalAfter(self):
             )
             self.checkLocals(code, ["a", "bar"])
 
+        def test_LocalDestructuring(self):
+            code = "def foo(x): y, *z = x"
+            self.checkLocals(code, ["x", "y", "z"])
+
     def test_LocalMadeGlobal(self):
         code = "def foo(): global a; a = 1"
         self.checkLocals(code, [])
@@ -468,4 +477,4 @@ def test_AssignmentSimple(self):
             a = a + 1
             a = a + 1
             """
-        self.checkLiveLocals(code, ["a:4"], ["a:2,3,4"])
+        self.checkLiveLocals(code, ["a:4"], ["a:2,3,4"])