feat(build): add eslint scripts and default configs

See https://github.com/typescript-eslint/typescript-eslint

.travis.yml

@@ -27,7 +27,7 @@ matrix:
       env: TASK=code-lint
       # Running Code Linter -- Requires @loopback/build so it's bootstrapped
       script:
-        - lerna bootstrap --scope @loopback/build --scope @loopback/tslint-config
+        - lerna bootstrap --scope @loopback/build --scope @loopback/tslint-config --scope @loopback/eslint-config
         - npm run lint
     - node_js: "8"
       os: linux

greenkeeper.json

@@ -18,6 +18,7 @@
         "packages/cli/package.json",
         "packages/context/package.json",
         "packages/core/package.json",
+        "packages/eslint-config/package.json",
         "packages/http-caching-proxy/package.json",
         "packages/http-server/package.json",
         "packages/metadata/package.json",
@@ -34,6 +35,5 @@
         "sandbox/example/package.json"
       ]
     }
-  },
-  "ignore": ["@types/node"]
+  }
 }

packages/build/bin/run-eslint.js

@@ -0,0 +1,49 @@
+#!/usr/bin/env node
+// Copyright IBM Corp. 2017,2018. All Rights Reserved.
+// Node module: @loopback/build
+// This file is licensed under the MIT License.
+// License text available at https://opensource.org/licenses/MIT
+
+/*
+========
+
+Usage:
+  node ./bin/run-eslint
+
+========
+*/
+
+'use strict';
+
+function run(argv, options) {
+  const utils = require('./utils');
+
+  const eslintOpts = argv.slice(2);
+
+  const isConfigSet = utils.isOptionSet(eslintOpts, '-c', '--config');
+  const isExtSet = utils.isOptionSet(eslintOpts, '--ext');
+
+  const eslintConfigFile = isConfigSet
+    ? null
+    : utils.getConfigFile('.eslintrc.js', '.eslintrc.json');
+
+  const eslintIgnoreFile = utils.getConfigFile('.eslintignore');
+
+  const args = [];
+  if (eslintConfigFile) {
+    args.push('-c', eslintConfigFile);
+  }
+  if (eslintIgnoreFile) {
+    args.push('--ignore-path', eslintIgnoreFile);
+  }
+
+  if (!isExtSet) {
+    args.push('--ext', '.js,.ts');
+  }
+  args.push(...eslintOpts);
+
+  return utils.runCLI('eslint/bin/eslint', args, options);
+}
+
+module.exports = run;
+if (require.main === module) run(process.argv);

packages/build/config/.eslintignore

@@ -0,0 +1,4 @@
+node_modules/
+dist/
+coverage/
+api-docs/

packages/build/config/.eslintrc.js

@@ -0,0 +1,3 @@
+module.exports = {
+  extends: '@loopback/eslint-config',
+};