feat(MongoMemoryServer): add isRunning() method

Closes #152

Author: nodkz

README.md

@@ -37,10 +37,19 @@ const dbPath = await mongod.getDbPath();
 const dbName = await mongod.getDbName();
 
 // some code
+//   ... where you may use `uri` for as a connection string for mongodb or mongoose
+
+// you may check instance status, after you got `uri` it must be `true`
+mongod.isRunning(); // return true
 
 // you may stop mongod manually
-mongod.stop();
-// or it will be stopped automatically when you exit from script
+await mongod.stop();
+
+// when mongod killed, it's running status should be `false`
+mongod.isRunning();
+
+// even you forget to stop `mongod` when you exit from script
+// special childProcess killer will shutdown it for you
 ```
 
 ### Available options

src/MongoMemoryServer.ts

@@ -62,6 +62,10 @@ export default class MongoMemoryServer {
     }
   }
 
+  isRunning(): boolean {
+    return !!this.runningInstance;
+  }
+
   async start(): Promise<boolean> {
     this.debug('Called MongoMemoryServer.start() method:');
     if (this.runningInstance) {

src/__tests__/MongoMemoryServer-test.ts

@@ -9,7 +9,7 @@ describe('MongoMemoryServer', () => {
     MongoMemoryServer = jest.requireActual('../MongoMemoryServer').default;
   });
 
-  describe('start', () => {
+  describe('start()', () => {
     it('should resolve to true if an MongoInstanceData is resolved by _startUpInstance', async () => {
       MongoMemoryServer.prototype._startUpInstance = jest.fn(() => Promise.resolve({} as any));
 
@@ -65,7 +65,7 @@ describe('MongoMemoryServer', () => {
     });
   });
 
-  describe('getInstanceData', () => {
+  describe('getInstanceData()', () => {
     it('should throw an error if not instance is running after calling start', async () => {
       MongoMemoryServer.prototype.start = jest.fn(() => Promise.resolve(true));
 
@@ -79,18 +79,18 @@ describe('MongoMemoryServer', () => {
     });
   });
 
-  describe('stop', () => {
-    it.only('should stop mongod', async () => {
-      console.log(MongoMemoryServer.prototype._startUpInstance);
+  describe('stop()', () => {
+    it('should stop mongod and answer on isRunning() method', async () => {
       const mongod = new MongoMemoryServer({
         autoStart: true,
-        debug: true,
+        debug: false,
       });
 
       await mongod.getInstanceData();
 
+      expect(mongod.isRunning()).toBeTruthy();
       await mongod.stop();
-      expect(mongod.runningInstance).toBe(null);
+      expect(mongod.isRunning()).toBeFalsy();
     });
   });
 });