zjquery: Avoid array-related hacks.

Callers can either explicitly pass in children,
stub out $(...)[0] as needed, or just
circumvent jQuery complications with override.

Note the reactions test was broken before,
since $(...)[0] was always returning the same
stub.

frontend_tests/node_tests/dispatch.js

@@ -203,6 +203,7 @@ run_test("hotspots", (override) => {
 });
 
 run_test("invites_changed", (override) => {
+    $.create("#admin-invites-list", {children: ["stub"]});
     const event = event_fixtures.invites_changed;
     const stub = make_stub();
     override(settings_invites, "set_up", stub.f);

frontend_tests/node_tests/drafts.js

@@ -301,6 +301,7 @@ run_test("format_drafts", (override) => {
     override(drafts, "open_overlay", noop);
     drafts.set_initial_element = noop;
 
+    $.create("#drafts_table .draft-row", {children: []});
     drafts.launch();
     timerender.render_now = stub_render_now;
 });

frontend_tests/node_tests/lightbox.js

@@ -22,7 +22,7 @@ set_global("popovers", {
 
 rows.is_draft_row = () => false;
 
-run_test("pan_and_zoom", () => {
+run_test("pan_and_zoom", (override) => {
     $.clear_all_elements();
 
     const img = $.create("img-stub");
@@ -33,7 +33,12 @@ run_test("pan_and_zoom", () => {
 
     img.set_parent(link);
     link.closest = () => msg;
-    msg.attr("zid", "1234");
+
+    override(rows, "id", (row) => {
+        assert.equal(row, msg);
+        return 1234;
+    });
+
     img.attr("src", "example");
 
     let fetched_zid;
@@ -51,7 +56,7 @@ run_test("pan_and_zoom", () => {
     assert.equal(fetched_zid, 1234);
 });
 
-run_test("youtube", () => {
+run_test("youtube", (override) => {
     $.clear_all_elements();
 
     const href = "https://youtube.com/some-random-clip";
@@ -59,7 +64,10 @@ run_test("youtube", () => {
     const link = $.create("link-stub");
     const msg = $.create("msg-stub");
 
-    msg.attr("zid", "4321");
+    override(rows, "id", (row) => {
+        assert.equal(row, msg);
+        return 4321;
+    });
 
     $(img).attr("src", href);
 

frontend_tests/node_tests/reactions.js

@@ -127,14 +127,14 @@ set_global("current_msg_list", {
 });
 
 run_test("open_reactions_popover", () => {
-    $(".selected-row").set_find_results(".actions_hover", $(".target-action"));
+    $(".selected-row").set_find_results(".actions_hover", ["action-stub"]);
-    $(".selected-row").set_find_results(".reaction_button", $(".target-reaction"));
+    $(".selected-row").set_find_results(".reaction_button", ["reaction-stub"]);
 
     let called = false;
     emoji_picker.toggle_emoji_popover = function (target, id) {
         called = true;
         assert.equal(id, 42);
-        assert.equal(target, $(".target-reaction")[0]);
+        assert.equal(target, "action-stub");
     };
 
     assert(reactions.open_reactions_popover());
@@ -148,7 +148,7 @@ run_test("open_reactions_popover", () => {
     emoji_picker.toggle_emoji_popover = function (target, id) {
         called = true;
         assert.equal(id, 42);
-        assert.equal(target, $(".target-action")[0]);
+        assert.equal(target, "reaction-stub");
     };
 
     assert(reactions.open_reactions_popover());

frontend_tests/node_tests/search.js

@@ -84,6 +84,8 @@ run_test("initialize", () => {
     const search_button = $(".search_button");
     const searchbox = $("#searchbox");
 
+    search_query_box[0] = "stub";
+
     search_pill.get_search_string_for_current_filter = function () {
         return "is:starred";
     };

frontend_tests/node_tests/settings_profile_fields.js

@@ -52,6 +52,8 @@ function test_populate(opts) {
     table.set_find_results("tr.profile-field-row", rows);
     table.set_find_results("tr.profile-field-form", form);
 
+    table[0] = "stub";
+
     let num_appends = 0;
     table.append = () => {
         num_appends += 1;

frontend_tests/node_tests/ui_init.js

@@ -187,5 +187,7 @@ run_test("initialize_everything", () => {
     compose.compute_show_video_chat_button = () => {};
     $("#below-compose-content .video_link").toggle = () => {};
 
+    $("<audio>")[0] = "stub";
+
     ui_init.initialize_everything();
 });

frontend_tests/zjsunit/zjquery.js

@@ -413,18 +413,20 @@ function make_new_elem(selector, opts) {
                 f.call(child);
             }
         };
+        self[Symbol.iterator] = function* () {
+            for (const child of opts.children) {
+                yield child;
+            }
+        };
+        self.length = opts.children.length;
     }
 
     if (selector[0] === "<") {
         self.html(selector);
     }
 
-    self[0] = "you-must-set-the-child-yourself";
-
     self.selector = selector;
 
-    self.length = 1;
-
     return self;
 }