test that names used in destructurings don't get hoisted

lib/compress.js

@@ -1280,7 +1280,6 @@ merge(Compressor.prototype, {
                 // collect only vars which don't show up in self's arguments list
                 var defs = [];
                 vars.each(function(def, name){
-                    // TODO test this too
                     if (self instanceof AST_Lambda
                         && find_if(function(x){ return x.name == def.name.name },
                                    self.args_as_names())) {

test/compress/hoist.js

@@ -0,0 +1,67 @@
+
+hoist_vars: {
+    options = {
+        hoist_vars: true
+    }
+    input: {
+        function a() {
+            bar();
+            var var1;
+            var var2;
+        }
+        function b(anArg) {
+            bar();
+            var var1;
+            var anArg;
+        }
+    }
+    expect: {
+        function a() {
+            var var1, var2;  // Vars go up and are joined
+            bar();
+        }
+        function b(anArg) {
+            var var1;
+            bar();
+            // But vars named like arguments go away!
+        }
+    }
+}
+
+hoist_funs: {
+    options = {
+        hoist_funs: true
+    }
+    input: {
+        function a() {
+            bar();
+            function foo() {}
+        }
+    }
+    expect: {
+        function a() {
+            function foo() {}  // Funs go up
+            bar();
+        }
+    }
+}
+
+hoist_no_destructurings: {
+    options = {
+        hoist_vars: true,
+        hoist_funs: true
+    }
+    input: {
+        function a([anArg]) {
+            bar();
+            var var1;
+            var anArg;  // Because anArg is already declared, this goes away!
+        }
+    }
+    expect: {
+        function a([anArg]) {
+            var var1;
+            bar();
+        }
+    }
+}