Moved labs usage into cancel_link helper file

- this removes the need to require the proxy inside the helpers/index.js file
- have the helper file define and return it's own labs-enabled-ness
- update the tests to test for the labs flag being unset

core/frontend/helpers/cancel_link.js

@@ -6,9 +6,9 @@
 //
 // Defaults to class="cancel-subscription-link" errorClass="cancel-subscription-error" cancelLabel="Cancel subscription" continueLabel="Continue subscription"
 
-const {templates, errors, i18n} = require('../services/proxy');
+const {templates, errors, i18n, labs} = require('../services/proxy');
 
-module.exports = function excerpt(options) {
+function cancel_link(options) { // eslint-disable-line camelcase
     let truncateOptions = (options || {}).hash || {};
 
     if (this.id === undefined || this.cancel_at_period_end === undefined) {
@@ -25,4 +25,18 @@ module.exports = function excerpt(options) {
     };
 
     return templates.execute('cancel_link', data);
+}
+
+module.exports = function cancelLabsWrapper() {
+    let self = this;
+    let args = arguments;
+
+    return labs.enabledHelper({
+        flagKey: 'members',
+        flagName: 'Members',
+        helperName: 'cancel_link',
+        helpUrl: 'https://ghost.org/faq/members/'
+    }, () => {
+        return cancel_link.apply(self, args);
+    });
 };

core/frontend/helpers/index.js

@@ -1,4 +1,3 @@
-const proxy = require('../services/proxy');
 const register = require('./register');
 
 const coreHelpers = {};
@@ -46,26 +45,13 @@ coreHelpers.title = require('./title');
 coreHelpers.twitter_url = require('./twitter_url');
 coreHelpers.url = require('./url');
 
-function labsEnabledMembers() {
-    let self = this, args = arguments;
-
-    return proxy.labs.enabledHelper({
-        flagKey: 'members',
-        flagName: 'Members',
-        helperName: 'cancel_link',
-        helpUrl: 'https://ghost.org/faq/members/'
-    }, () => {
-        return coreHelpers.cancel_link.apply(self, args);
-    });
-}
-
 registerAllCoreHelpers = function registerAllCoreHelpers() {
     // Register theme helpers
     registerThemeHelper('asset', coreHelpers.asset);
     registerThemeHelper('author', coreHelpers.author);
     registerThemeHelper('authors', coreHelpers.authors);
     registerThemeHelper('body_class', coreHelpers.body_class);
-    registerThemeHelper('cancel_link', labsEnabledMembers);
+    registerThemeHelper('cancel_link', coreHelpers.cancel_link);
     registerThemeHelper('concat', coreHelpers.concat);
     registerThemeHelper('content', coreHelpers.content);
     registerThemeHelper('date', coreHelpers.date);

test/unit/helpers/cancel_link_spec.js

@@ -1,9 +1,12 @@
 const should = require('should');
+const sinon = require('sinon');
 const hbs = require('../../../core/frontend/services/themes/engine');
 const helpers = require('../../../core/frontend/helpers');
+const labs = require('../../../core/server/services/labs');
 const configUtils = require('../../utils/configUtils');
 
 describe('{{cancel_link}} helper', function () {
+    let labsStub;
     before(function (done) {
         hbs.express4({partialsDir: [configUtils.config.get('paths').helperTemplates]});
 
@@ -12,6 +15,14 @@ describe('{{cancel_link}} helper', function () {
         });
     });
 
+    beforeEach(function () {
+        labsStub = sinon.stub(labs, 'isSet').returns(true);
+    });
+
+    afterEach(function () {
+        sinon.restore();
+    });
+
     const defaultLinkClass = /class="gh-subscription-cancel"/;
     const defaultErrorElementClass = /class="gh-error gh-error-subscription-cancel"/;
     const defaultCancelLinkText = /Cancel subscription/;
@@ -25,7 +36,10 @@ describe('{{cancel_link}} helper', function () {
         };
 
         runHelper('not an object').should.throw();
-        runHelper(function () {}).should.throw();
+        runHelper(function () { }).should.throw();
+        runHelper({}).should.throw();
+        runHelper({id: ''}).should.throw();
+        runHelper({cancel_at_period_end: ''}).should.throw();
     });
 
     it('can render cancel subscription link', function () {
@@ -109,4 +123,18 @@ describe('{{cancel_link}} helper', function () {
 
         rendered.string.should.match(/custom continue link text/);
     });
+
+    it('is disabled if labs flag is not set', function () {
+        labsStub.returns(false);
+
+        const rendered = helpers.cancel_link.call({
+            id: 'sub_continue',
+            cancel_at_period_end: true
+        });
+
+        should.exist(rendered);
+
+        rendered.string.should.match(/^<script/);
+        rendered.string.should.match(/helper is not available/);
+    });
 });