test: add test for isThing guard

test/Guards.spec.ts

@@ -0,0 +1,57 @@
+/*
+ * Copyright (C) 2018, 2019 StApps
+ * This program is free software: you can redistribute it and/or modify it
+ * under the terms of the GNU General Public License as published by the Free
+ * Software Foundation, version 3.
+ *
+ * This program is distributed in the hope that it will be useful, but WITHOUT
+ * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
+ * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License for
+ * more details.
+ *
+ * You should have received a copy of the GNU General Public License along with
+ * this program. If not, see <https://www.gnu.org/licenses/>.
+ */
+import {expect} from 'chai';
+import {slow, suite, test, timeout} from 'mocha-typescript';
+import {SCThingOriginType, SCThingType} from '../src/core/Thing';
+import {SCDish} from '../src/core/things/Dish';
+import {isThing} from '../src/core/types/Guards';
+
+@suite(timeout(10000), slow(5000))
+export class GuardsSpec {
+  @test
+  public isThing() {
+    const notADish = {
+      categories: [
+        'appetizer',
+      ],
+      name: 'foo',
+      origin: {
+        created: '',
+        type: SCThingOriginType.User,
+      },
+      type: 'foobar',
+      uid: 'bar',
+    };
+
+    const dish: SCDish = {
+      categories: [
+        'appetizer',
+      ],
+      name: 'foo',
+      origin: {
+        created: '',
+        type: SCThingOriginType.User,
+      },
+      type: SCThingType.Dish,
+      uid: 'bar',
+    };
+
+    expect(isThing('foo')).to.be.equal(false);
+
+    expect(isThing(notADish)).to.be.equal(false);
+
+    expect(isThing(dish)).to.be.equal(true);
+  }
+}