fix corner case in rests (#5109)

fixes #5108

lib/compress.js

@@ -12313,8 +12313,10 @@ merge(Compressor.prototype, {
 
     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 = self.rest.rest;
+            return make_node(AST_DestructuredArray, self, {
+                elements: self.elements.concat(self.rest.elements),
+                rest: self.rest.rest,
+            });
         }
         return self;
     });

test/compress/rests.js

@@ -1069,3 +1069,25 @@ issue_5100_2: {
     expect_stdout: "PASS"
     node_version: ">=10"
 }
+
+issue_5108: {
+    options = {
+        evaluate: true,
+        reduce_vars: true,
+        rests: true,
+        unsafe: true,
+        unused: true,
+    }
+    input: {
+        console.log(function([ ...[ a ] ]) {
+            return a;
+        }([ "PASS", "FAIL" ]));
+    }
+    expect: {
+        console.log(function([]) {
+            return "PASS";
+        }([ "PASS", "FAIL" ]));
+    }
+    expect_stdout: "PASS"
+    node_version: ">=6"
+}