MOBILE-3320 tests: Add base error tests

package-lock.json

@@ -8219,6 +8219,12 @@
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       "integrity": "sha1-4mifjzVvrWLMplo6kcXfX5VRaS8="
     },
+    "faker": {
+      "version": "5.1.0",
+      "resolved": "https://registry.npmjs.org/faker/-/faker-5.1.0.tgz",
+      "integrity": "sha512-RrWKFSSA/aNLP0g3o2WW1Zez7/MnMr7xkiZmoCfAGZmdkDQZ6l2KtuXHN5XjdvpRjDl8+3vf+Rrtl06Z352+Mw==",
+      "dev": true
+    },
     "fast-deep-equal": {
       "version": "3.1.3",
       "resolved": "https://registry.npmjs.org/fast-deep-equal/-/fast-deep-equal-3.1.3.tgz",

package.json

@@ -130,6 +130,7 @@
     "eslint-plugin-jest": "^24.1.0",
     "eslint-plugin-jsdoc": "^30.6.3",
     "eslint-plugin-prefer-arrow": "^1.2.2",
+    "faker": "^5.1.0",
     "jest": "^26.5.0",
     "jest-preset-angular": "^8.3.1",
     "ts-jest": "^26.4.1",

src/app/classes/error.test.ts

@@ -0,0 +1,73 @@
+// (C) Copyright 2015 Moodle Pty Ltd.
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+//     http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License 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.
+import Faker from 'faker';
+
+import { CoreError } from './error';
+
+describe('CoreError', () => {
+    it('behaves like an error', () => {
+        // Arrange
+        const message = Faker.lorem.sentence();
+
+        let error: CoreError | null = null;
+
+        // Act
+        try {
+            throw new CoreError(message);
+        } catch (e) {
+            error = e;
+        }
+
+        // Assert
+        expect(error).not.toBeNull();
+        expect(error).toBeInstanceOf(Error);
+        expect(error).toBeInstanceOf(CoreError);
+        expect(error!.name).toEqual('CoreError');
+        expect(error!.message).toEqual(message);
+        expect(error!.stack).not.toBeNull();
+        expect(error!.stack).toContain('src/app/classes/error.test.ts');
+    });
+
+    it('can be subclassed', () => {
+        // Arrange
+        class CustomCoreError extends CoreError {
+
+            constructor(m: string) {
+                super(`Custom message: ${m}`);
+            }
+
+        }
+
+        const message = Faker.lorem.sentence();
+
+        let error: CustomCoreError | null = null;
+
+        // Act
+        try {
+            throw new CustomCoreError(message);
+        } catch (e) {
+            error = e;
+        }
+
+        // Assert
+        expect(error).not.toBeNull();
+        expect(error).toBeInstanceOf(Error);
+        expect(error).toBeInstanceOf(CoreError);
+        expect(error).toBeInstanceOf(CustomCoreError);
+        expect(error!.name).toEqual('CustomCoreError');
+        expect(error!.message).toEqual(`Custom message: ${message}`);
+        expect(error!.stack).not.toBeNull();
+        expect(error!.stack).toContain('src/app/classes/error.test.ts');
+    });
+});