Merge pull request #126 from mcampa/STENCIL-3845-unless-helper

STENCIL-3845 Unless helper

helpers/if.js

@@ -3,28 +3,38 @@
 var _ = require('lodash');
 
 function helper(paper) {
+    paper.handlebars.registerHelper('unless', function () {
+        const options = arguments[arguments.length - 1];
+        arguments[arguments.length - 1] = Object.assign({}, options, {
+            fn: options.inverse || (() => false),
+            inverse: options.fn || (() => true),
+            hash: options.hash
+        });
+
+        return paper.handlebars.helpers['if'].apply(this, arguments);
+    });
+
     paper.handlebars.registerHelper('if', function (lvalue, operator, rvalue) {
         const options = arguments[arguments.length - 1];
-        var result;
+        let result;
 
         function isOptions(obj) {
             return _.isObject(obj) && obj.fn;
         }
 
         // Only parameter
         if (isOptions(operator)) {
-
             // If an array is passed as the only parameter
             if (_.isArray(lvalue)) {
-                result = lvalue.length;
+                result = !!lvalue.length;
             }
             // If an empty object is passed, treat as false
             else if (_.isEmpty(lvalue) && _.isObject(lvalue)) {
                 result = false;
             }
             // Everything else
             else {
-                result = lvalue;
+                result = !!lvalue;
             }
         } else {
 
@@ -77,14 +87,15 @@ function helper(paper) {
             }
         }
 
-        if (options.fn) { // block helper
-            if (result) {
-                return options.fn(this);
-            } else {
-                return options.inverse(this);
-            }
-        } else { // non-block helper
-            return result;
+        if (!options.fn || !options.inverse) {
+            options.fn = () => true;
+            options.inverse = () => false;
+        }
+
+        if (result) {
+            return options.fn(this);
+        } else {
+            return options.inverse(this);
         }
     });
 }

test/helpers/if.js

@@ -10,17 +10,18 @@ function c(template, context) {
     return new Paper().loadTemplatesSync({template: template}).render('template', context);
 }
 
-describe('if helper', function() {
+describe('if helper', () => {
     var context = {
         num1: 1,
         num2: 2,
         product: {a: 1, b: 2},
         string: 'yolo',
         alwaysTrue: true,
+        alwaysFalse: true,
         big: 'big'
     };
 
-    it('should have the same behavior as the original if helper', function(done) {
+    it('should have the same behavior as the original if helper', done => {
         expect(c('{{#if 1}}{{big}}{{/if}}', context))
             .to.be.equal('big');
 
@@ -54,7 +55,7 @@ describe('if helper', function() {
         done();
     });
 
-    it('should render "big" if all conditions match', function(done) {
+    it('should render "big" if all conditions match', done => {
 
         expect(c('{{#if "1" "==" num1}}big{{/if}}', context))
             .to.be.equal('big');
@@ -89,7 +90,7 @@ describe('if helper', function() {
         done();
     });
 
-    it('should render empty for all cases', function(done) {
+    it('should render empty for all cases', done => {
 
         expect(c('{{#if "2" "==" num1}}big{{/if}}', context))
             .to.be.equal('');
@@ -125,7 +126,7 @@ describe('if helper', function() {
     });
 
 
-    it('should render "big" if all ifs match', function(done) {
+    it('should render "big" if all ifs match', done => {
 
         var context = {
             num1: 1,
@@ -167,9 +168,8 @@ describe('if helper', function() {
         done();
     });
 
-    it('should render empty for all cases', function(done) {
-
-        var context = {
+    it('should render empty for all cases', done => {
+        const context = {
             num1: 1,
             num2: 2,
             product: {a: 1, b: 2},
@@ -220,7 +220,7 @@ describe('if helper', function() {
         done();
     });
 
-    it('should work as a non-block helper when used as a subexpression', function(done) {
+    it('should work as a non-block helper when used as a subexpression', done => {
         expect(c('{{#if (if num1 "!==" num2)}}{{big}}{{/if}}', context))
             .to.be.equal('big');
 
@@ -229,5 +229,62 @@ describe('if helper', function() {
 
         done();
     });
-
 });
+
+describe('unless helper', () => {
+    const context = {
+        num1: 1,
+        num2: 2,
+        product: {a: 1, b: 2},
+        alwaysTrue: true,
+        alwaysFalse: false,
+        notEmptyArray: [ 1, 2 , 3 ],
+        emptyArray: [],
+    };
+
+    it('should print hello', done => {
+        expect(c('{{#unless num1 "===" num2}}hello{{/unless}}', context))
+            .to.be.equal('hello');
+
+        expect(c('{{#unless alwaysFalse}}hello{{/unless}}', context))
+            .to.be.equal('hello');
+
+        expect(c('{{#unless does_not_exist}}hello{{/unless}}', context))
+            .to.be.equal('hello');
+
+        done();
+    });
+
+    it('should print empty', done => {
+        expect(c('{{#unless num1 "===" num1}}hello{{/unless}}', context))
+            .to.be.equal('');
+
+        expect(c('{{#unless alwaysTrue}}hello{{/unless}}', context))
+            .to.be.equal('');
+
+        expect(c('{{#unless product}}hello{{/unless}}', context))
+            .to.be.equal('');
+
+        done();
+    });
+
+    it('should work with arrays', done => {
+        expect(c('{{#unless emptyArray}}foo{{else}}bar{{/unless}}', context))
+            .to.be.equal('foo');
+
+        expect(c('{{#unless notEmptyArray}}foo{{else}}bar{{/unless}}', context))
+            .to.be.equal('bar');
+
+        done();
+    });
+
+    it('should work as a non-block helper when used as a subexpression', done => {
+        expect(c('{{#if (unless num1 "===" num2)}}big{{/if}}', context))
+            .to.be.equal('big');
+
+        expect(c('{{#all (unless num1 "===" num2) "1" true}}big{{/all}}', context))
+            .to.be.equal('big');
+
+        done();
+    });
+})