bugfix: glimmer-2 issue #800

frameworks/keyed/glimmer-2/src/MyTable.ts

@@ -7,6 +7,11 @@ import { run, runLots, add, update, swapRows, deleteRow } from './utils/benchmar
 
 import TableRow from './TableRow';
 import BsButton from './BsButton';
+import { helper } from './utils/helper';
+
+const eq = helper(([a,b]) => {
+  return a === b;
+})
 
 export default class MyTable extends Component {
   @tracked id = 1;
@@ -47,27 +52,18 @@ export default class MyTable extends Component {
   }
 
   @action remove(id): void {
-    const selected = this.data.find(({ selected }) => selected === true);
-    if (selected) {
-      selected.selected = false;
-    }
     this.data = deleteRow(this.data, id);
     this.selected = undefined;
   }
 
   @action select(id): void {
     this.selected = id;
-    const selected = this.data.find(({ selected }) => selected === true);
-    if (selected) {
-      selected.selected = false;
-    }
-    this.data.find((item) => item.id === id).selected = true;
   }
 }
 
 setComponentTemplate(
   createTemplate(
-    { on, fn, TableRow, BsButton },
+    { on, fn, eq, TableRow, BsButton },
     `
 <div class="jumbotron">
   <div class="row">
@@ -112,7 +108,7 @@ setComponentTemplate(
 </div>
 <table class="table table-hover table-striped test-data">
   <tbody>
-    {{#each this.data key="id" as |item|}}<TableRow @item={{item}} @onSelect={{fn this.select item.id}} @onRemove={{fn this.remove item.id}} />{{/each}}
+    {{#each this.data key="id" as |item|}}<TableRow class={{if (eq this.selected item.id) 'danger'}} @item={{item}} @onSelect={{fn this.select item.id}} @onRemove={{fn this.remove item.id}} />{{/each}}
   </tbody>
 </table>
 <span class="preloadicon glyphicon glyphicon-remove" aria-hidden="true"></span>`), MyTable

frameworks/keyed/glimmer-2/src/TableRow.ts

@@ -4,7 +4,7 @@ import { createTemplate, setComponentTemplate, templateOnlyComponent } from '@gl
 export default setComponentTemplate(
   createTemplate(
     { on },
-    `<tr class={{if @item.selected "danger"}}><td class="col-md-1">{{@item.id}}</td><td class="col-md-4"><a {{on 'click' @onSelect}}>{{@item.label}}</a></td><td class="col-md-1"><a {{on 'click' @onRemove}}><span class="glyphicon glyphicon-remove" aria-hidden="true"></span></a></td><td class="col-md-6"></td></tr>`
+    `<tr ...attributes><td class="col-md-1">{{@item.id}}</td><td class="col-md-4"><a {{on 'click' @onSelect}}>{{@item.label}}</a></td><td class="col-md-1"><a {{on 'click' @onRemove}}><span class="glyphicon glyphicon-remove" aria-hidden="true"></span></a></td><td class="col-md-6"></td></tr>`
   ),
   templateOnlyComponent()
 );

frameworks/keyed/glimmer-2/src/utils/benchmark-helpers.ts

@@ -2,11 +2,9 @@ import { tracked } from '@glimmer/tracking';
 
 class TodoItem {
   @tracked label;
-  @tracked selected;
   @tracked id;
-  constructor({ label, selected, id }) {
+  constructor({ label, id }) {
     this.label = label;
-    this.selected = selected;
     this.id = id;
   }
 }
@@ -92,7 +90,6 @@ export const buildData = (id, count = 1000): ItemsSnapshot => {
     data.push(
       new TodoItem({
         id: id++,
-        selected: false,
         label:
           adjectives[_random(adjectives.length)] +
           ' ' +

frameworks/keyed/glimmer-2/src/utils/helper.ts

@@ -0,0 +1,34 @@
+import { helperCapabilities, HelperManager, setHelperManager } from '@glimmer/core';
+
+type helperFunc<
+  Positional extends unknown[] = unknown[],
+  Result = unknown
+> = (positional: Positional) => Result;
+
+interface HelperBucket<
+  Positional extends unknown[] = unknown[],
+  Result = unknown
+> {
+  fn: helperFunc<Positional, Result>;
+  args: any;
+}
+
+class HelperWithServicesManager implements HelperManager<HelperBucket> {
+  capabilities = helperCapabilities('glimmerjs-2.0.0');
+
+  createHelper(fn: helperFunc, args: any): HelperBucket {
+    return { fn, args };
+  }
+
+  getValue(instance: HelperBucket): unknown {
+    const { args } = instance;
+    return instance.fn(args.positional);
+  }
+}
+
+const HelperWithServicesManagerFactory = (): HelperWithServicesManager => new HelperWithServicesManager();
+
+export function helper<T extends Function>(fn: T): T {
+  setHelperManager(HelperWithServicesManagerFactory, fn);
+  return fn;
+}