[Feature] Add 'memorySearch' and 'memorySearchSync' for Nodejs

1) Add features.
2) Add unit tests.
3) Add benchmark.

binding/nodejs/tests/unitTests/exceptionTest.spec.js

@@ -0,0 +1,28 @@
+// This test is used for tesing of exceptions
+
+const IP2Region = require('../../ip2region');
+
+describe('Constructor Test', () => {
+  let instance;
+
+  beforeAll(() => {
+    instance = new IP2Region({ dbPath: '../../data/ip2region.db' })
+  });
+
+  afterAll(() => {
+    instance.destroy();
+  });
+
+  test('IP invalid test', () => {
+    const invalidIps = ['255.234.233', '255.255.-1.255', null, undefined, '', 'x.255.y.200'];
+    for (const ip of invalidIps) {
+      expect(() => instance.btreeSearchSync(ip)).toThrow();
+      expect(() => instance.binarySearchSync(ip)).toThrow();
+    }
+  });
+
+  test('File Not Found test', () => {
+    expect(() => new IP2Region({ dbPath: 'A Bad File or Path Here' })).toThrow();
+  });
+
+});