setup-rendering-context: Protect element and context methods from o…

…verwriting
emberjs · Mar 26, 2018 · c3a0bb1 · c3a0bb1
1 parent 6aa7b9d
commit c3a0bb1
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Showing 2 changed files with 30 additions and 15 deletions.
diff --git a/addon-test-support/@ember/test-helpers/setup-rendering-context.js b/addon-test-support/@ember/test-helpers/setup-rendering-context.js
@@ -154,11 +154,11 @@ export default function setupRenderingContext(context) {
       // these methods being placed on the context itself will be deprecated in
       // a future version (no giant rush) to remove some confusion about which
       // is the "right" way to things...
-      context.render = render;
-      context.clearRender = clearRender;
+      Object.defineProperty(context, 'render', { value: render, writable: false });
+      Object.defineProperty(context, 'clearRender', { value:clearRender, writable: false });
 
       if (global.jQuery) {
-        context.$ = jQuerySelector;
+        Object.defineProperty(context, '$', { value: jQuerySelector, writable: false });
       }
 
       // When the host app uses `setApplication` (instead of `setResolver`) the event dispatcher has
@@ -190,18 +190,20 @@ export default function setupRenderingContext(context) {
       });
     })
     .then(() => {
-      // ensure the element is based on the wrapping toplevel view
-      // Ember still wraps the main application template with a
-      // normal tagged view
-      //
-      // In older Ember versions (2.4) the element itself is not stable,
-      // and therefore we cannot update the `this.element` until after the
-      // rendering is completed
-      if (EmberENV._APPLICATION_TEMPLATE_WRAPPER !== false) {
-        context.element = getRootElement().querySelector('.ember-view');
-      } else {
-        context.element = getRootElement();
-      }
+      Object.defineProperty(context, 'element', {
+        // ensure the element is based on the wrapping toplevel view
+        // Ember still wraps the main application template with a
+        // normal tagged view
+        //
+        // In older Ember versions (2.4) the element itself is not stable,
+        // and therefore we cannot update the `this.element` until after the
+        // rendering is completed
+        value: EmberENV._APPLICATION_TEMPLATE_WRAPPER !== false
+          ? getRootElement().querySelector('.ember-view')
+          : getRootElement(),
+
+        writable: false,
+      });
 
       return context;
     });

diff --git a/tests/unit/setup-rendering-context-test.js b/tests/unit/setup-rendering-context-test.js
@@ -30,6 +30,14 @@ module('setupRenderingContext', function(hooks) {
     setResolver(resolver);
   });
 
+  function overwriteTest(key) {
+    test(`throws an error when trying to overwrite this.${key}`, function(assert) {
+      assert.throws(() => {
+        this[key] = null;
+      }, TypeError);
+    });
+  }
+
   function setupRenderingContextTests(hooks) {
     hooks.beforeEach(async function() {
       setResolverRegistry({
@@ -72,6 +80,8 @@ module('setupRenderingContext', function(hooks) {
       });
     }
 
+    overwriteTest('element');
+
     test('render can be used multiple times', async function(assert) {
       await this.render(hbs`<p>Hello!</p>`);
       assert.equal(this.element.textContent, 'Hello!');
@@ -108,6 +118,9 @@ module('setupRenderingContext', function(hooks) {
       assert.strictEqual(this.element, originalElement, 'this.element is stable');
     });
 
+    overwriteTest('render');
+    overwriteTest('clearRender');
+
     (hasjQuery() ? test : skip)('this.$ is exposed when jQuery is present', async function(assert) {
       await this.render(hbs`<p>Hello!</p>`);