chore(project): add test coverage

* monitor coverage via codecov
* run coverage locally via COVERAGE=1 npm test

.gitignore

@@ -1,5 +1,6 @@
 node_modules/
 dist/
+coverage/
 .idea
 *.iml
 .DS_Store

.travis.yml

@@ -10,7 +10,8 @@ jobs:
       addons:
         firefox: 'latest-esr'
       script:
-        - TEST_BROWSERS=Firefox,PhantomJS xvfb-run npm run all
+        - COVERAGE=1 TEST_BROWSERS=Firefox,PhantomJS xvfb-run npm run all
+        - codecov
     - stage: update integration test
       script: './tasks/stages/update-integration-test'
     - stage: update examples

package.json

@@ -41,14 +41,17 @@
   "devDependencies": {
     "chai": "^4.1.2",
     "chai-match": "^1.1.1",
+    "codecov": "^3.1.0",
     "cpx": "^1.5.0",
     "del": "^3.0.0",
     "eslint": "^4.19.0",
     "eslint-plugin-bpmn-io": "^0.5.2",
     "execa": "^0.8.0",
+    "istanbul-instrumenter-loader": "^3.0.1",
     "jsondiffpatch": "^0.1.26",
-    "karma": "^2.0.2",
+    "karma": "^2.0.5",
     "karma-chrome-launcher": "^2.1.1",
+    "karma-coverage": "^1.1.2",
     "karma-env-preprocessor": "^0.1.1",
     "karma-firefox-launcher": "^1.0.1",
     "karma-ie-launcher": "^1.0.0",

test/all.js

@@ -0,0 +1,7 @@
+var allTests = require.context('.', true, /(spec|integration).*Spec\.js$/);
+
+allTests.keys().forEach(allTests);
+
+var allSources = require.context('../lib', true, /.*\.js$/);
+
+allSources.keys().forEach(allSources);

test/config/karma.unit.js

@@ -1,3 +1,5 @@
+var coverage = process.env.COVERAGE;
+
 var path = require('path');
 
 var basePath = '../../';
@@ -25,6 +27,8 @@ var browsers =
       return browser;
     });
 
+var suite = coverage ? 'test/all.js' : 'test/suite.js';
+
 
 module.exports = function(karma) {
   karma.set({
@@ -37,14 +41,14 @@ module.exports = function(karma) {
     ],
 
     files: [
-      'test/suite.js'
+      suite
     ],
 
     preprocessors: {
-      'test/suite.js': [ 'webpack', 'env' ]
+      [ suite ]: [ 'webpack', 'env' ]
     },
 
-    reporters: [ 'spec' ],
+    reporters: [ 'spec' ].concat(coverage ? 'coverage' : []),
 
     customLaunchers: {
       ChromeHeadless_Linux: {
@@ -57,6 +61,12 @@ module.exports = function(karma) {
       }
     },
 
+    coverageReporter: {
+      reporters: [
+        { type: 'lcov', subdir: '.' }
+      ]
+    },
+
     browsers: browsers,
 
     browserNoActivityTimeout: 30000,
@@ -64,7 +74,6 @@ module.exports = function(karma) {
     singleRun: true,
     autoWatch: false,
 
-
     webpack: {
       mode: 'development',
       module: {
@@ -73,7 +82,17 @@ module.exports = function(karma) {
             test: /\.css|\.bpmn$/,
             use: 'raw-loader'
           }
-        ]
+        ].concat(coverage ?
+          {
+            test: /\.js$/,
+            use: {
+              loader: 'istanbul-instrumenter-loader',
+              options: { esModules: true }
+            },
+            include: /lib\.*/,
+            exclude: /node_modules/
+          } : []
+        )
       },
       resolve: {
         mainFields: [