Fixing the coverage issue when PR

Signed-off-by: Fabio José <fabiojose@gmail.com>

.travis.yml

@@ -27,15 +27,8 @@ jobs:
       on:
         tags: true
 
-  - stage: coverage
-    node_js: '6'
-    deploy:
-      provider: script
-      script: npm run coverage
-      on:
-        branch: master
-      on:
-        branch: develop
 env:
   global:
     secure: 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
+script:
+  - if [ "$TRAVIS_PULL_REQUEST" == "false" ]; then npm run coverage-publish; fi

package.json

@@ -4,8 +4,8 @@
   "description": "CloudEvents SDK for JavaScript",
   "main": "index.js",
   "scripts": {
-    "test": "./node_modules/.bin/mocha -C test/**/*.js",
-    "coverage": "./node_modules/.bin/istanbul cover -x '**/test/**' _mocha --report lcovonly -- -R spec && cat ./coverage/lcov.info | ./node_modules/.bin/codacy-coverage && rm -rf ./coverage"
+    "test": "./node_modules/.bin/istanbul cover -x 'test/**/*.js' _mocha -- -C test/**/*.js",
+    "coverage-publish": "./node_modules/.bin/istanbul cover -x 'test/**/*.js' _mocha --report lcovonly -- -C test/**/*.js -R spec && cat ./coverage/lcov.info | ./node_modules/.bin/codacy-coverage && rm -rf ./coverage"
   },
   "repository": {
     "type": "git",