`return undefined` optimization no longer uses `return_void_0` option

2 files changed, 3 insertions, 147 deletions

diff --git a/lib/compress.js b/lib/compress.js
index ebe7e957..50353fe0 100644
--- a/lib/compress.js
+++ b/lib/compress.js
@@ -65,7 +65,6 @@ function Compressor(options, false_by_default) {
         keep_fnames   : false,
         hoist_vars    : false,
         if_return     : !false_by_default,
-        return_void_0 : !false_by_default,
         join_vars     : !false_by_default,
         cascade       : !false_by_default,
         side_effects  : !false_by_default,
@@ -2521,10 +2520,8 @@ merge(Compressor.prototype, {
     OPT(AST_RegExp, literals_in_boolean_context);
 
     OPT(AST_Return, function(self, compressor){
-        if (compressor.option("return_void_0")) {
-            if (self.value instanceof AST_Undefined) {
-                self.value = null;
-            }
+        if (self.value instanceof AST_Undefined) {
+            self.value = null;
         }
         return self;
     });
diff --git a/test/compress/return_undefined.js b/test/compress/return_undefined.js
index b1195a72..9662aa51 100644
--- a/test/compress/return_undefined.js
+++ b/test/compress/return_undefined.js
@@ -1,6 +1,5 @@
-return_void_0_true: {
+return_undefined: {
     options = {
-        return_void_0 : true,
         sequences     : false,
         if_return     : true,
         evaluate      : true,
@@ -123,143 +122,3 @@ return_void_0_true: {
         }
     }
 }
-
-return_void_0_false: {
-    options = {
-        return_void_0 : false,
-        sequences     : false,
-        if_return     : true,
-        evaluate      : true,
-        dead_code     : true,
-        conditionals  : true,
-        comparisons   : true,
-        booleans      : true,
-        unused        : true,
-        side_effects  : true,
-        properties    : true,
-        drop_debugger : true,
-        loops         : true,
-        hoist_funs    : true,
-        keep_fargs    : true,
-        keep_fnames   : false,
-        hoist_vars    : true,
-        join_vars     : true,
-        cascade       : true,
-        negate_iife   : true
-    };
-    input: {
-        function f0() {
-        }
-        function f1() {
-            return undefined;
-        }
-        function f2() {
-            return void 0;
-        }
-        function f3() {
-            return void 123;
-        }
-        function f4() {
-            return;
-        }
-        function f5(a, b) {
-            console.log(a, b);
-            baz(a);
-            return;
-        }
-        function f6(a, b) {
-            console.log(a, b);
-            if (a) {
-                foo(b);
-                baz(a);
-                return a + b;
-            }
-            return undefined;
-        }
-        function f7(a, b) {
-            console.log(a, b);
-            if (a) {
-                foo(b);
-                baz(a);
-                return void 0;
-            }
-            return a + b;
-        }
-        function f8(a, b) {
-            foo(a);
-            bar(b);
-            return void 0;
-        }
-        function f9(a, b) {
-            foo(a);
-            bar(b);
-            return undefined;
-        }
-        function f10() {
-            return false;
-        }
-        function f11() {
-            return null;
-        }
-        function f12() {
-            return 0;
-        }
-    }
-    expect: {
-        function f0() {
-        }
-        function f1() {
-            return void 0;
-        }
-        function f2() {
-            return void 0;
-        }
-        function f3() {
-            return void 0;
-        }
-        function f4() {
-        }
-        function f5(a, b) {
-            console.log(a, b);
-            baz(a);
-        }
-        function f6(a, b) {
-            console.log(a, b);
-            if (a) {
-                foo(b);
-                baz(a);
-                return a + b;
-            }
-            return void 0;
-        }
-        function f7(a, b) {
-            console.log(a, b);
-            if (a) {
-                foo(b);
-                baz(a);
-                return void 0;
-            }
-            return a + b;
-        }
-        function f8(a, b) {
-            foo(a);
-            bar(b);
-            return void 0;
-        }
-        function f9(a, b) {
-            foo(a);
-            bar(b);
-            return void 0;
-        }
-        function f10() {
-            return !1;
-        }
-        function f11() {
-            return null;
-        }
-        function f12() {
-            return 0;
-        }
-    }
-}
-