Service is killed when webpack watch is done

This fixes #27 by making sure the service is killed when the watch
task emits the "watch-close" event.
This fix only works with webpack >= 2.3.0 otherwise it's effectively a
noop because the event will never be emitted.

Author: trash

lib/index.js

@@ -146,6 +146,10 @@ ForkTsCheckerWebpackPlugin.prototype.pluginStart = function () {
 };
 
 ForkTsCheckerWebpackPlugin.prototype.pluginStop = function () {
+  this.compiler.plugin('watch-close', function () {
+    this.killService();
+  }.bind(this));
+
   this.compiler.plugin('done', function () {
     if (!this.isWatching) {
       this.killService();

package.json

@@ -55,7 +55,7 @@
   },
   "peerDependencies": {
     "typescript": "^2.1.0",
-    "webpack": "^2.0.0 || ^3.0.0"
+    "webpack": "^2.3.0 || ^3.0.0"
   },
   "dependencies": {
     "babel-code-frame": "^6.22.0",

test/integration/index.spec.js

@@ -8,8 +8,11 @@ var ForkTsCheckerWebpackPlugin = require('../../lib/index');
 
 describe('[INTEGRATION] index', function () {
   this.timeout(30000);
+  var plugin;
 
   function createCompiler(options) {
+    plugin = new ForkTsCheckerWebpackPlugin(Object.assign({}, options, { silent: true }));
+
     return webpack({
       context: path.resolve(__dirname, './project'),
       entry: './src/index.ts',
@@ -29,11 +32,20 @@ describe('[INTEGRATION] index', function () {
         ]
       },
       plugins: [
-        new ForkTsCheckerWebpackPlugin(Object.assign({}, options, { silent: true }))
+        plugin
       ]
     });
   }
 
+  /**
+   * Implicitly check whether killService was called by checking that
+   * the service property was set to undefined.
+   * @returns [boolean] true if killService was called
+   */
+  function killServiceWasCalled() {
+    return plugin.service === undefined;
+  }
+
   it('should allow to pass no options', function () {
     expect(function () {
       new ForkTsCheckerWebpackPlugin();
@@ -108,6 +120,18 @@ describe('[INTEGRATION] index', function () {
     });
   });
 
+  it('kills the service when the watch is done', function (done) {
+    var compiler = createCompiler();
+    var watching = compiler.watch({}, function() {});
+
+    compiler.plugin('fork-ts-checker-done', function () {
+      watching.close(function() {
+        expect(killServiceWasCalled()).to.be.true;
+        done();
+      });
+    });
+  });
+
   it('should throw error if config container wrong tsconfig.json path', function () {
     expect(function() {
       createCompiler({