ci: drop support for node 6

.eslintrc.yml

@@ -2,7 +2,7 @@ env:
   node: true
 
 parserOptions:
-  ecmaVersion: 6
+  ecmaVersion: 8
 
 extends:
   - eslint:recommended

.travis.yml

@@ -4,9 +4,9 @@ sudo: false
 
 # test on node.js versions
 node_js:
+  - '12'
   - '10'
   - '8'
-  - '6'
 
 services:
   - redis-server

package.json

@@ -2,6 +2,9 @@
   "name": "bull",
   "version": "3.9.1",
   "description": "Job manager",
+  "engines": {
+    "node": ">=8"
+  },
   "main": "./index.js",
   "repository": {
     "type": "git",
@@ -24,7 +27,7 @@
     "lodash": "^4.17.11",
     "p-timeout": "^2.0.1",
     "promise.prototype.finally": "^3.1.0",
-    "semver": "^5.6.0",
+    "semver": "^6.1.1",
     "util.promisify": "^1.0.0",
     "uuid": "^3.2.1"
   },
@@ -40,7 +43,7 @@
     "husky": "^1.3.1",
     "istanbul": "^0.4.5",
     "lint-staged": "^8.1.0",
-    "mocha": "^5.1.1",
+    "mocha": "^6.1.4",
     "mocha-lcov-reporter": "^1.3.0",
     "moment": "^2.24.0",
     "p-reflect": "^1.0.0",
@@ -70,8 +73,5 @@
     "hooks": {
       "commit-msg": "commitlint -E HUSKY_GIT_PARAMS"
     }
-  },
-  "engines": {
-    "node": ">= 6"
   }
 }