1 files changed, 25 insertions, 0 deletions

diff --git a/lib/compress.js b/lib/compress.js
index 83d20e8f..c9bd182e 100644
--- a/2020-10-18
@@ -4871,8 +4871,18 @@ merge(Compressor.prototype, {
         return trim_block(self);
     });
 
+    function drop_rest_farg(fn, compressor) {
+        if (!compressor.option("rests")) return;
+        if (fn.uses_arguments) return;
+        if (!(fn.rest instanceof AST_DestructuredArray)) return;
+        if (!compressor.drop_fargs(fn, compressor.parent())) return;
+        fn.argnames = fn.argnames.concat(fn.rest.elements);
+        fn.rest = null;
+    }
+
     function opt_arrow(self, compressor) {
         if (!compressor.option("arrows")) return self;
+        drop_rest_farg(self, compressor);
         var body = tighten_body(self.value ? [ self.first_statement() ] : self.body, compressor);
         switch (body.length) {
           case 1:
@@ -4892,7 +4902,14 @@ merge(Compressor.prototype, {
     OPT(AST_Arrow, opt_arrow);
     OPT(AST_AsyncArrow, opt_arrow);
 
+    OPT(AST_Defun, function(self, compressor) {
+        drop_rest_farg(self, compressor);
+        self.body = tighten_body(self.body, compressor);
+        return self;
+    });
+
     OPT(AST_Function, function(self, compressor) {
+        drop_rest_farg(self, compressor);
         self.body = tighten_body(self.body, compressor);
         if (compressor.option("inline")) for (var i = 0; i < self.body.length; i++) {
             var stat = self.body[i];
@@ -10686,6 +10703,14 @@ merge(Compressor.prototype, {
         return try_evaluate(compressor, self);
     });
 
+    OPT(AST_DestructuredArray, function(self, compressor) {
+        if (compressor.option("rests") && self.rest instanceof AST_DestructuredArray) {
+            self.elements = self.elements.concat(self.rest.elements);
+            self.rest = null;
+        }
+        return self;
+    });
+
     OPT(AST_DestructuredKeyVal, function(self, compressor) {
         if (compressor.option("objects")) {
             var key = self.key;