[BUGFIX Release] Special case {{#with}} for isTruthy

packages/ember-htmlbars/lib/hooks/link-render-node.js

@@ -25,8 +25,9 @@ export default function linkRenderNode(renderNode, env, scope, path, params, has
     switch (path) {
       case 'unbound': return true;
       case 'unless':
-      case 'if': params[0] = shouldDisplay(params[0]); break;
+      case 'if': params[0] = shouldDisplay(params[0], toBool); break;
       case 'each': params[0] = eachParam(params[0]); break;
+      case 'with': params[0] = shouldDisplay(params[0], identity); break;
     }
   }
 
@@ -76,7 +77,7 @@ function eachParam(list) {
   return stream;
 }
 
-function shouldDisplay(predicate) {
+function shouldDisplay(predicate, coercer) {
   let length = getKey(predicate, 'length');
   let isTruthy = getKey(predicate, 'isTruthy');
 
@@ -93,7 +94,7 @@ function shouldDisplay(predicate) {
       return isTruthyVal;
     }
 
-    return !!predicateVal;
+    return coercer(predicateVal);
   }, 'ShouldDisplay');
 
   addDependency(stream, length);
@@ -102,6 +103,14 @@ function shouldDisplay(predicate) {
   return stream;
 }
 
+function toBool(value) {
+  return !!value;
+}
+
+function identity(value) {
+  return value;
+}
+
 function getKey(obj, key) {
   if (isStream(obj)) {
     return obj.getKey(key);

packages/ember-htmlbars/tests/helpers/with_test.js

@@ -99,6 +99,79 @@ QUnit.test('re-using the same variable with different #with blocks does not over
   equal(view.$().text(), 'Admin: Tom Dale User: Yehuda Katz', 'should be properly scoped');
 });
 
+QUnit.test('should respect `isTruthy` field on a view', function() {
+  view = EmberView.create({
+    template: compile('{{#with view}}True{{else}}False{{/with}}'),
+    isTruthy: true
+  });
+  runAppend(view);
+
+  equal(view.$().text(), 'True');
+
+  run(function() {
+    set(view, 'isTruthy', false);
+  });
+
+  equal(view.$().text(), 'False');
+
+  run(function() {
+    set(view, 'isTruthy', true);
+  });
+
+  equal(view.$().text(), 'True');
+});
+
+QUnit.test('should respect `isTruthy` field on an object', function() {
+  view = EmberView.create({
+    template: compile('{{#with view.foo}}True{{else}}False{{/with}}'),
+    foo: {
+      isTruthy: true
+    }
+  });
+  runAppend(view);
+
+  equal(view.$().text(), 'True');
+
+  run(function() {
+    set(view, 'foo.isTruthy', false);
+  });
+
+  equal(view.$().text(), 'False');
+
+  run(function() {
+    set(view, 'foo.isTruthy', true);
+  });
+
+  equal(view.$().text(), 'True');
+});
+
+QUnit.test('should respect `isTruthy` field on the context object', function() {
+  view = EmberView.create({
+    template: compile('{{#with foo}}True{{else}}False{{/with}}'),
+    context: {
+      foo: {
+        isTruthy: true
+      }
+    }
+  });
+
+  runAppend(view);
+
+  equal(view.$().text(), 'True');
+
+  run(function() {
+    set(view, 'context.foo.isTruthy', false);
+  });
+
+  equal(view.$().text(), 'False');
+
+  run(function() {
+    set(view, 'context.foo.isTruthy', true);
+  });
+
+  equal(view.$().text(), 'True');
+});
+
 QUnit.test('the scoped variable is not available outside the {{with}} block.', function() {
   view = EmberView.create({
     template: compile('{{name}}-{{#with other as |name|}}{{name}}{{/with}}-{{name}}'),