Improve code quality and write tests

node_modules/codecov/lib/services/gitlab.js

@@ -0,0 +1,25 @@
+// https://docs.gitlab.com/ce/ci/variables/README.html
+
+module.exports = {
+  detect: function() {
+    return !!process.env.GITLAB_CI
+  },
+
+  configuration: function() {
+    console.log('    Gitlab CI Detected')
+    var remote =
+      process.env.CI_BUILD_REPO || process.env.CI_REPOSITORY_URL || ''
+    return {
+      service: 'gitlab',
+      build: process.env.CI_BUILD_ID,
+      commit: process.env.CI_BUILD_REF,
+      branch: process.env.CI_BUILD_REF_NAME,
+      root: process.env.CI_PROJECT_DIR,
+      slug: remote
+        .split('/')
+        .slice(3, 5)
+        .join('/')
+        .replace('.git', ''),
+    }
+  },
+}