Fix object pattern rest transpilation when assigning to a non-simple-name, like ({a, ...b.rest} = o});

PiperOrigin-RevId: 857198731

Author: lauraharker

src/com/google/javascript/jscomp/Es6RewriteDestructuring.java

@@ -565,9 +565,10 @@ private void replaceObjectPattern(
 
         Node restName = child.getOnlyChild(); // e.g. get `rest` from `const {...rest} = {};`
         if (restName.getString().startsWith(DESTRUCTURING_TEMP_VAR)) {
+          checkState(restName.isName(), restName);
           newLHS = createTempVarNameNode(restName.getString(), type(restName));
         } else {
-          newLHS = astFactory.createName(restName.getString(), type(restName));
+          newLHS = restName.detach();
         }
         newRHS = objectPatternRestRHS(objectPattern, child, restTempVarName, propsToDeleteForRest);
       } else {

test/com/google/javascript/jscomp/Es6RewriteDestructuringTest.java

@@ -1600,8 +1600,6 @@ public void testObjectPatternWithRestAssignStatement() {
 
   @Test
   public void testObjectPatternWithRestAssignStatement_assignedToProperty() {
-    // TODO: b/475285460 - fix the output of this test: it should assign to `obj.rest`, not just
-    // `rest`.
     test(
         "var a, obj = {}; ({a, ...obj.rest} = foo());",
         """
@@ -1610,7 +1608,7 @@ public void testObjectPatternWithRestAssignStatement_assignedToProperty() {
         var $jscomp$destructuring$var0 = foo();
         var $jscomp$destructuring$var1 = Object.assign({}, $jscomp$destructuring$var0);
         a = $jscomp$destructuring$var0.a;
-        rest = (delete $jscomp$destructuring$var1.a, $jscomp$destructuring$var1);
+        obj.rest = (delete $jscomp$destructuring$var1.a, $jscomp$destructuring$var1);
         """);
   }