Merge pull request #10 from toyokumo/feature/introduce_eslint

Use eslint

.circleci/config.yml

@@ -15,6 +15,9 @@ jobs:
           key: dependency-cache-{{ checksum "package.json" }}
           paths:
             - ./node_modules
+      - run:
+          name: lint
+          command: npm run lint
       - run:
           name: test
           command: npm test

.eslintrc.json

@@ -0,0 +1,30 @@
+{
+  "extends": [
+    "eslint:recommended",
+    "plugin:@typescript-eslint/eslint-recommended",
+    "plugin:@typescript-eslint/recommended",
+    "plugin:prettier/recommended",
+    "prettier/@typescript-eslint"
+  ],
+  "plugins": [
+    "@typescript-eslint"
+  ],
+  "env": {
+    "node": true,
+    "es6": true,
+    "browser": true
+  },
+  "parser": "@typescript-eslint/parser",
+  "parserOptions": {
+    "sourceType": "module",
+    "project": "./tsconfig.eslint.json"
+  },
+  "rules": {
+    "@typescript-eslint/no-unused-vars": [
+      "error",
+      {
+        "argsIgnorePattern": "^_"
+      }
+    ]
+  }
+}