ESLinting (#3850)

* Removing @typescript-eslint/eslint-recommended

Since plugin:@typescript-eslint/recommended is already extending it.

* Marking eslint configs as root

* Removing unused tslint.json configurations

* Using eslint in realm-intergration-tests

* Reordering plugins in the config

* Adding lerna: scripts to root package

* Publishing realm-app-importer on the default repository

* Adding a lint script to electron and node

* Fixed trivial false-negatives

* Ignoring the example packages

* Creating a workflow to lint on PRs

* Hoisting eslint to the root

* Switched around name and run in workflow

* Simplifying eslint configs by relying on cascading

* A more default prettier config

* Minor adjustments to the eslint configs

* Updated header to match the copyright date as a pattern

* Simplified eslintconfig in types

* Upgraded to node v14 & npm v7 in workflows

* Adding npm >= 7 to engines

* Removed linting in the realm-web workflow

* Minor change to the eslint configs

* Don't use npm v7 on windows

* Renamed job

* Fixing eslint config errors

* Adding a guide and vscode configuration files

* Removed unwanted dependecies on tslint

* Swapped if: and run: in workflow

* Removed linting from test.sh and Jenkinsfile

* Updated package-locks

.eslintignore

@@ -13,3 +13,5 @@ vendor/
 # The sub-packages have their own linting
 /integration-tests/
 /packages/
+/examples/
+/tests/ReactTestApp/

.eslintrc.json

@@ -1,29 +1,15 @@
 {
   "root": true,
+  "extends": [
+    "eslint:recommended",
+    "plugin:prettier/recommended",
+    "./header.eslintrc"
+  ],
   "env": {
-    "es2017": true,
-    "node": true
+    "es2017": true
   },
-  "extends": "eslint:recommended",
-  "rules": {
-    "comma-dangle": 0,
-    "no-empty": 0,
-    "no-console": 0,
-    "no-unused-vars": [
-      "warn",
-      {
-        "varsIgnorePattern": "^_",
-        "args": "none"
-      }
-    ],
-    "strict": [
-      2,
-      "global"
-    ],
-    "quotes": [
-      1,
-      "double"
-    ]
+  "parserOptions": {
+    "ecmaVersion": 2018
   },
   "settings": {
     "react": {

.github/workflows/integration-tests.yml

@@ -35,6 +35,10 @@ jobs:
         with:
           node-version: ${{ matrix.node }}
           registry-url: https://registry.npmjs.org/
+      - name: Install npm v7
+        # TODO: Remove the following line once we've found a workaround for https://github.com/dotnet/msbuild/issues/5726
+        if: ${{ matrix.os != 'windows-latest' }}
+        run: npm install -g npm@7
       # The following is a noop on non-windows runners
       - name: Install Microsoft Visual C++ cmd tools
         uses: ilammy/msvc-dev-cmd@v1
@@ -71,8 +75,10 @@ jobs:
           submodules: 'recursive'
       - uses: actions/setup-node@v1
         with:
-          node-version: 12
+          node-version: 14
           registry-url: https://registry.npmjs.org/
+      - name: Install npm v7
+        run: npm install -g npm@7
       # Install the root package (--ignore-scripts to avoid downloading or building the native module)
       - run: npm ci --ignore-scripts
       # Bootstrap lerna sub-packages (builds the packages and Realm JS native module)
@@ -103,8 +109,10 @@ jobs:
           submodules: 'recursive'
       - uses: actions/setup-node@v1
         with:
-          node-version: 12
+          node-version: 14
           registry-url: https://registry.npmjs.org/
+      - name: Install npm v7
+        run: npm install -g npm@7
       # Setup tools
       - name: Install tools
         run: brew install watchman
@@ -181,8 +189,10 @@ jobs:
           submodules: 'recursive'
       - uses: actions/setup-node@v1
         with:
-          node-version: 12
+          node-version: 14
           registry-url: https://registry.npmjs.org/
+      - name: Install npm v7
+        run: npm install -g npm@7
       # Setup tools
       - name: Install tools
         run: brew install watchman

.github/workflows/pr-linting.yml

@@ -0,0 +1,28 @@
+name: Linting (Pull Request)
+
+on:
+  pull_request:
+    paths:
+      # No need to run when updating documentation
+      - '!**.md'
+
+jobs:
+  lint:
+    name: Lint
+    runs-on: ubuntu-latest
+
+    steps:
+      - uses: actions/checkout@v2
+      - uses: actions/setup-node@v1
+        with:
+          node-version: 14
+          registry-url: https://registry.npmjs.org/
+      - name: Install npm v7
+        run: npm install -g npm@7
+      # Install the root package (--ignore-scripts to avoid downloading or building the native module)
+      - name: Install root package dependencies
+        run: npm ci --ignore-scripts
+      - name: Install subpackages dependencies
+        run: npm run lerna:bootstrap
+      - name: Run linting of subpackages
+        run: npm run lerna:lint -- --no-bail --concurrency 1 --stream --no-prefix

.github/workflows/pr-realm-web.yml

@@ -11,23 +11,23 @@ on:
       - '!**.md'
 
 jobs:
-  test-build-and-publish:
-    name: Test, lint and build
+  job:
+    name: Build & test
     runs-on: ubuntu-latest
 
     steps:
       - uses: actions/checkout@v2
       - uses: actions/setup-node@v1
         with:
-          node-version: 12
+          node-version: 14
           registry-url: https://registry.npmjs.org/
+      - name: Install npm v7
+        run: npm install -g npm@7
       # Install the root package (--ignore-scripts to avoid downloading or building the native module)
       - run: npm ci --ignore-scripts
       # Bootstrap lerna sub-packages
       - run: npx lerna bootstrap --scope realm-web-integration-tests --include-dependencies
-      # Lint, build and test the package
-      - run: npm run lint
-        working-directory: packages/realm-web
+      # Build and test the package
       - run: npm run build
         working-directory: packages/realm-web
       - name: Run unit tests

.github/workflows/publish-realm-web.yml

@@ -14,8 +14,10 @@ jobs:
       - uses: actions/checkout@v2
       - uses: actions/setup-node@v1
         with:
-          node-version: 12
+          node-version: 14
           registry-url: https://registry.npmjs.org/
+      - name: Install npm v7
+        run: npm install -g npm@7
       # Install the root package
       - run: npm ci
       # Bootstrap lerna sub-packages

.prettierrc.js

@@ -1,7 +1,4 @@
 module.exports = {
-    jsxBracketSameLine: true,
     trailingComma: 'all',
-    tabWidth: 4,
-    arrowParens: 'avoid',
-    // printWidth: 120,
+    printWidth: 120,
 };

.vscode/extensions.json

@@ -0,0 +1,5 @@
+{
+  "recommendations": [
+    "dbaeumer.vscode-eslint"
+  ]
+}

.vscode/settings.json

@@ -0,0 +1,7 @@
+{
+  "eslint.workingDirectories": [
+    {
+      "mode": "auto"
+    }
+  ]
+}

Jenkinsfile

@@ -84,18 +84,6 @@ if (packagesExclusivelyChanged) {
 
 stage('pretest') {
   parallelExecutors = [:]
-    parallelExecutors["eslint"] = testLinux("eslint-ci Release ${nodeTestVersion}", { // "Release" is not used
-    step([
-      $class: 'CheckStylePublisher',
-      canComputeNew: false,
-      canRunOnFailed: true,
-      defaultEncoding: '',
-      healthy: '',
-      pattern: 'eslint.xml',
-      unHealthy: '',
-      maxWarnings: 0,
-      ignoreFailures: false])
-  })
     parallelExecutors["jsdoc"] = testLinux("jsdoc Release ${nodeTestVersion}", { // "Release is not used
     publishHTML([
       allowMissing: false,

contrib/linting.md

@@ -0,0 +1,44 @@
+# Keeping our code style aligned with linting
+
+We're using linters for a couple of reasons:
+- We've experienced a lot of reviews to focus on the stying of code rather than its design and architecture. In particular, this has the potential to be a real turn-off for a newcomer.
+- Writing code in a shared style makes way easier to read across files.
+- As with any static analysis of code, linting has the potential to find bugs before our users do.
+
+## Setup your editor to format on save
+
+To help yourself keep your code passing linters at all times, it's highly recommended to setup your editor to help you.
+
+### Visual Studio Code
+
+- Install and enable the ["eslint" extension for VS Code](https://marketplace.visualstudio.com/items?itemName=dbaeumer.vscode-eslint).
+- Make sure you've enabled "format on save" on your workspace.
+
+Both the eslint plugin and formatting on save can be enabled via the UI or you can <kbd>Cmd</kbd> + <kbd>P</kbd>, type *"> Preferences Open Workspace Settings (JSON)"* and paste in the following in the `settings` object:
+
+```json
+"eslint.format.enable": true,
+"editor.formatOnSave": true
+```
+
+## Running the linters off the CLI
+
+Linters are run for every pull-request, via [the `pr-linting` workflow](../.github/workflows/pr-linting.yml) on GitHub Actions.
+
+Every package of this mono-repository should have a `lint` script - to lint, simply change your working directory and run the script:
+
+```
+npm run lint
+```
+
+To run linting on every package of the project, use the `lerna:lint` script in the root package:
+
+```
+npm run lerna:lint
+```
+
+The linter can automatically fix some issues. To run a fix across every sub-package, you can use the `lerna:lint:fix` script in the root package:
+
+```
+npm run lerna:lint:fix
+```

examples/ReactExample/package.json

@@ -19,7 +19,6 @@
     "moment": "2.19.1"
   },
   "devDependencies": {
-    "eslint": "^4.18.2",
     "fs-extra": "^4.0.3",
     "graceful-fs": "^4.2.6",
     "install-local": "^1.0.0",
@@ -29,4 +28,4 @@
   "localDependencies": {
     "realm": "../.."
   }
-}
+}

header.eslintrc.js

@@ -0,0 +1,48 @@
+////////////////////////////////////////////////////////////////////////////
+//
+// Copyright 2021 Realm Inc.
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+// http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+//
+////////////////////////////////////////////////////////////////////////////
+
+/* eslint-env node */
+
+const currentYear = new Date().getFullYear();
+
+const header = [
+  "//////////////////////////////////////////////////////////////////////////",
+  "",
+  { pattern: " Copyright \\d{4} Realm Inc.", template: ` Copyright ${currentYear} Realm Inc.` },
+  "",
+  ' Licensed under the Apache License, Version 2.0 (the "License");',
+  " you may not use this file except in compliance with the License.",
+  " You may obtain a copy of the License at",
+  "",
+  " http://www.apache.org/licenses/LICENSE-2.0",
+  "",
+  " Unless required by applicable law or agreed to in writing, software",
+  ' distributed under the License is distributed on an "AS IS" BASIS,',
+  " WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.",
+  " See the License for the specific language governing permissions and",
+  " limitations under the License.",
+  "",
+  "//////////////////////////////////////////////////////////////////////////",
+];
+
+module.exports = {
+  plugins: ["header"],
+  rules: {
+    "header/header": ["error", "line", header],
+  },
+};

integration-tests/environments/electron/.eslintrc.json

@@ -1,6 +1,5 @@
 {
-    "extends": "../../../.eslintrc.json",
-    "parserOptions": {
-        "ecmaVersion": 2018
-    }
-}
+  "env": {
+    "node": true
+  }
+}

integration-tests/environments/electron/package.json

@@ -10,6 +10,7 @@
   "private": true,
   "main": "app/main.js",
   "scripts": {
+    "lint": "eslint .",
     "package": "electron-builder --dir",
     "runner:main": "node runner.js main",
     "runner:renderer": "node runner.js renderer",
@@ -53,4 +54,4 @@
       "!node_modules/realm/vendor${/*}"
     ]
   }
-}
+}

integration-tests/environments/node/.eslintrc.json

@@ -1,6 +1,6 @@
 {
-    "extends": "../../../.eslintrc.json",
     "env": {
-        "mocha": true
+        "mocha": true,
+        "node": true
     }
-}
+}

integration-tests/environments/node/package.json

@@ -4,8 +4,9 @@
   "description": "Realm JS tests running in a Node.js environment",
   "private": true,
   "scripts": {
-    "test": "mocha-remote -- concurrently npm:app-importer npm:start",
     "start": "node index.js",
+    "test": "mocha-remote -- concurrently npm:app-importer npm:start",
+    "lint": "eslint .",
     "app-importer": "realm-app-importer serve ../../realm-apps"
   },
   "dependencies": {
@@ -27,4 +28,4 @@
     "concurrently": "^6.0.2",
     "realm-app-importer": "*"
   }
-}
+}

integration-tests/environments/react-native/.eslintrc.json

@@ -1,6 +1,6 @@
 {
   "extends": [
-      "@react-native-community",
-      "../../../.eslintrc.json"
+    "@react-native-community",
+    "../../../.eslintrc"
   ]
 }