test: add registerTemplate

This commit adds multiple tests for the
registerTemplate function of the lib/register/template.js
file.

__tests__/register/template.test.js

@@ -0,0 +1,108 @@
+/*
+ * Copyright 2017 Amazon.com, Inc. or its affiliates. All Rights Reserved.
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License"). You may not use this file except in compliance with
+ * the License. A copy of the License is located at
+ *
+ * http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * or in the "license" file accompanying this file. This file is distributed on an "AS IS" BASIS, WITHOUT WARRANTIES OR
+ * CONDITIONS OF ANY KIND, either express or implied. See the License for the specific language governing permissions
+ * and limitations under the License.
+ */
+
+var assert = require('chai').assert;
+var StyleDictionary = require('../../index').extend({});
+
+
+describe('registerTemplate', function() {
+  it('should error if name is not a string', function() {
+    assert.throws(
+      StyleDictionary.registerTemplate.bind(null, {}),
+      Error,
+      /Template name must be a string:/
+    );
+
+    assert.throws(
+      StyleDictionary.registerTemplate.bind(null, {
+        name: 1,
+      }),
+      Error,
+      /Template name must be a string:/
+    );
+
+    assert.throws(
+      StyleDictionary.registerTemplate.bind(null, {
+        name: [],
+      }),
+      Error,
+      /Template name must be a string:/
+    );
+
+    assert.throws(
+      StyleDictionary.registerTemplate.bind(null, {
+        name: {},
+      }),
+      Error,
+      /Template name must be a string:/
+    );
+  });
+
+  it('should error if path is not a string', function() {
+    assert.throws(
+      StyleDictionary.registerTemplate.bind(null, {
+        name: 'data',
+      }),
+      Error,
+      /Template path must be a string:/
+    );
+
+    assert.throws(
+      StyleDictionary.registerTemplate.bind(null, {
+        name: 'data',
+        template: 1,
+      }),
+      Error,
+      /Template path must be a string:/
+    );
+
+    assert.throws(
+      StyleDictionary.registerTemplate.bind(null, {
+        name: 'data',
+        template: [],
+      }),
+      Error,
+      /Template path must be a string:/
+    );
+
+    assert.throws(
+      StyleDictionary.registerTemplate.bind(null, {
+        name: 'data',
+        template: {},
+      }),
+      Error,
+      /Template path must be a string:/
+    );
+  });
+
+  it('should error if path is not a file', function() {
+    assert.throws(
+      StyleDictionary.registerTemplate.bind(null, {
+        name: 'data',
+        template: 'non_existent_file',
+      }),
+      Error,
+      /Can\'t find template: /
+    );
+  });
+
+  it('should return StyleDictionary', function() {
+    assert(
+      StyleDictionary.registerTemplate.bind(null, {
+        name: 'data',
+        template: 'registerTemplate.js',
+      }),
+      StyleDictionary
+    );
+  });
+});