Move the shared ESLint plugin/config into the monorepo (#24670)

* Move the shared ESLint plugin/config into the monorepo

* Add peer dependencies to ESLint plugin

webapp/channels/.eslintrc.json

@@ -1,11 +1,11 @@
 {
   "root": true,
   "extends": [
-    "plugin:mattermost/react",
+    "plugin:@mattermost/react",
     "plugin:react-hooks/recommended"
   ],
   "plugins": [
-    "mattermost",
+    "@mattermost",
     "import",
     "no-only-tests",
     "@typescript-eslint",
@@ -23,6 +23,7 @@
     }
   },
   "rules": {
+    "@mattermost/use-external-link": 2,
     "header/header": [
       2,
       "line",
@@ -30,7 +31,6 @@
       2
     ],
     "no-duplicate-imports": 0,
-    "mattermost/use-external-link": 2,
     "import/no-duplicates": 2,
     "max-nested-callbacks": ["error", 10],
     "no-unused-expressions": 0,

webapp/channels/package.json

@@ -102,6 +102,7 @@
   "devDependencies": {
     "@deanwhillier/jest-matchmedia-mock": "1.2.0",
     "@hot-loader/react-dom": "17.0.2",
+    "@mattermost/eslint-plugin": "*",
     "@redux-devtools/extension": "3.2.3",
     "@testing-library/jest-dom": "5.16.4",
     "@testing-library/react": "12.1.4",
@@ -148,7 +149,6 @@
     "enzyme-to-json": "3.6.2",
     "eslint-plugin-header": "3.1.1",
     "eslint-plugin-import": "2.27.5",
-    "eslint-plugin-mattermost": "github:mattermost/eslint-plugin-mattermost#5b0c972eacf19286e4c66221b39113bf8728a99e",
     "eslint-plugin-no-only-tests": "3.1.0",
     "eslint-plugin-react": "7.32.2",
     "eslint-plugin-react-hooks": "4.6.0",

webapp/channels/src/components/external_link/index.tsx

@@ -1,7 +1,7 @@
 // Copyright (c) 2015-present Mattermost, Inc. All Rights Reserved.
 // See LICENSE.txt for license information.
 
-/* eslint-disable mattermost/use-external-link */
+/* eslint-disable @mattermost/use-external-link */
 
 import React from 'react';
 import {useSelector} from 'react-redux';

webapp/channels/src/components/size_aware_image.jsx

@@ -1,7 +1,7 @@
 // Copyright (c) 2015-present Mattermost, Inc. All Rights Reserved.
 // See LICENSE.txt for license information.
 
-/* eslint-disable mattermost/use-external-link */
+/* eslint-disable @mattermost/use-external-link */
 
 import classNames from 'classnames';
 import PropTypes from 'prop-types';

webapp/package.json

@@ -51,6 +51,7 @@
     "channels",
     "platform/client",
     "platform/components",
+    "platform/eslint-plugin",
     "platform/types"
   ]
 }

webapp/platform/eslint-plugin/LICENSE.txt

@@ -0,0 +1,203 @@
+Copyright 2015-present Mattermost, Inc.
+
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+   TERMS AND CONDITIONS FOR USE, REPRODUCTION, AND DISTRIBUTION
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webapp/platform/eslint-plugin/README.md

@@ -0,0 +1,55 @@
+# @mattermost/eslint-plugin
+
+An ESLint plugin containing the configuration used by Mattermost as well as support for custom rules specific to the Mattermost code base.
+
+## Custom Rules
+
+### no-dispatch-getstate
+
+Prevents passing a [redux](https://redux.js.org/) store's `getState` into its `dispatch` as an unnecessary second argument.
+
+We started doing this accidentally at some point because of a misunderstanding about how [redux-thunk](https://github.com/reduxjs/redux-thunk) worked, so this stops anyone from making that same mistake again.
+
+Examples of **incorrect** code for this rule:
+```javascript
+export function someAction() {
+    return (dispatch, getState) => {
+        dispatch(doSomething(), getState);
+    };
+}
+```
+
+Examples of **correct** code for this rule:
+```javascript
+export function someAction() {
+    return (dispatch) => {
+        dispatch(doSomething());
+    };
+}
+```
+
+### use-external-link
+
+Ensures that any link which opens a URL outside of Mattermost using `target="_blank"` uses the `ExternalLink` component.
+
+Examples of **incorrect** code for this rule:
+```javascript
+export function SomeLink() {
+    return (
+        <a
+            href="https://example.com"
+            target="_blank"
+            rel="noopener noreferrer"
+        />
+    );
+}
+```
+
+Examples of **correct** code for this rule:
+```javascript
+import ExternalLink from 'components/external_link';
+
+export function SomeLink() {
+    return <ExternalLink href="https://example.com"/>;
+}
+```

webapp/platform/eslint-plugin/configs/.eslintrc-react.json

@@ -0,0 +1,123 @@
+{
+  "extends": [
+    "plugin:react/recommended"
+  ],
+  "plugins": [
+    "react"
+  ],
+  "rules": {
+    "react/display-name": [
+      0,
+      {
+        "ignoreTranspilerName": false
+      }
+    ],
+    "react/forbid-component-props": 0,
+    "react/forbid-elements": [
+      2,
+      {
+        "forbid": [
+          "embed"
+        ]
+      }
+    ],
+    "react/jsx-boolean-value": [
+      2,
+      "always"
+    ],
+    "react/jsx-closing-bracket-location": [
+      2,
+      {
+        "location": "tag-aligned"
+      }
+    ],
+    "react/jsx-curly-spacing": [
+      2,
+      "never"
+    ],
+    "react/jsx-equals-spacing": [
+      2,
+      "never"
+    ],
+    "react/jsx-filename-extension": 2,
+    "react/jsx-first-prop-new-line": [
+      2,
+      "multiline"
+    ],
+    "react/jsx-handler-names": 0,
+    "react/jsx-indent": [
+      2,
+      4
+    ],
+    "react/jsx-indent-props": [
+      2,
+      4
+    ],
+    "react/jsx-key": 2,
+    "react/jsx-max-props-per-line": [
+      2,
+      {
+        "maximum": 1
+      }
+    ],
+    "react/jsx-no-bind": 0,
+    "react/jsx-no-comment-textnodes": 2,
+    "react/jsx-no-duplicate-props": [
+      2,
+      {
+        "ignoreCase": false
+      }
+    ],
+    "react/jsx-no-literals": 2,
+    "react/jsx-no-target-blank": 2,
+    "react/jsx-no-undef": 2,
+    "react/jsx-pascal-case": 2,
+    "react/jsx-tag-spacing": [
+      2,
+      {
+        "closingSlash": "never",
+        "beforeSelfClosing": "never",
+        "afterOpening": "never"
+      }
+    ],
+    "react/jsx-uses-react": 2,
+    "react/jsx-uses-vars": 2,
+    "react/jsx-wrap-multilines": 2,
+    "react/no-array-index-key": 1,
+    "react/no-children-prop": 2,
+    "react/no-danger": 0,
+    "react/no-danger-with-children": 2,
+    "react/no-deprecated": 1,
+    "react/no-did-mount-set-state": 2,
+    "react/no-did-update-set-state": 2,
+    "react/no-direct-mutation-state": 2,
+    "react/no-find-dom-node": 1,
+    "react/no-is-mounted": 2,
+    "react/no-multi-comp": [
+      2,
+      {
+        "ignoreStateless": true
+      }
+    ],
+    "react/no-render-return-value": 2,
+    "react/no-set-state": 0,
+    "react/no-string-refs": 0,
+    "react/no-unescaped-entities": 2,
+    "react/no-unknown-property": 2,
+    "react/no-unused-prop-types": [
+      1,
+      {
+        "skipShapeProps": true
+      }
+    ],
+    "react/prefer-es6-class": 2,
+    "react/prefer-stateless-function": 0,
+    "react/prop-types": 2,
+    "react/require-default-props": 0,
+    "react/require-optimization": 1,
+    "react/require-render-return": 2,
+    "react/self-closing-comp": 2,
+    "react/sort-comp": 0,
+    "react/style-prop-object": 2
+  }
+}

webapp/platform/eslint-plugin/configs/.eslintrc.json

@@ -0,0 +1,506 @@
+{
+  "extends": [
+    "eslint:recommended"
+  ],
+  "parserOptions": {
+    "ecmaVersion": 8,
+    "sourceType": "module",
+    "ecmaFeatures": {
+      "jsx": true,
+      "impliedStrict": true,
+      "modules": true
+    }
+  },
+  "parser": "babel-eslint",
+  "plugins": [
+    "header"
+  ],
+  "env": {
+    "browser": true,
+    "node": true,
+    "jquery": true,
+    "es6": true
+  },
+  "rules": {
+    "@mattermost/no-dispatch-getstate": 2,
+    "array-bracket-spacing": [
+      2,
+      "never"
+    ],
+    "array-callback-return": 2,
+    "arrow-body-style": 0,
+    "arrow-parens": [
+      2,
+      "always"
+    ],
+    "arrow-spacing": [
+      2,
+      {
+        "before": true,
+        "after": true
+      }
+    ],
+    "block-scoped-var": 2,
+    "brace-style": [
+      2,
+      "1tbs",
+      {
+        "allowSingleLine": false
+      }
+    ],
+    "camelcase": [
+      2,
+      {
+        "properties": "never"
+      }
+    ],
+    "capitalized-comments": 0,
+    "class-methods-use-this": 0,
+    "comma-dangle": [
+      2,
+      "always-multiline"
+    ],
+    "comma-spacing": [
+      2,
+      {
+        "before": false,
+        "after": true
+      }
+    ],
+    "comma-style": [
+      2,
+      "last"
+    ],
+    "complexity": [
+      0,
+      10
+    ],
+    "computed-property-spacing": [
+      2,
+      "never"
+    ],
+    "consistent-return": 2,
+    "consistent-this": [
+      2,
+      "self"
+    ],
+    "constructor-super": 2,
+    "curly": [
+      2,
+      "all"
+    ],
+    "dot-location": [
+      2,
+      "object"
+    ],
+    "dot-notation": 2,
+    "eqeqeq": [
+      2,
+      "smart"
+    ],
+    "func-call-spacing": [
+      2,
+      "never"
+    ],
+    "func-name-matching": 0,
+    "func-names": 2,
+    "func-style": [
+      2,
+      "declaration",
+      {
+        "allowArrowFunctions": true
+      }
+    ],
+    "generator-star-spacing": [
+      2,
+      {
+        "before": false,
+        "after": true
+      }
+    ],
+    "global-require": 2,
+    "guard-for-in": 2,
+    "header/header": [
+      2,
+      "line",
+      " Copyright (c) 2015-present Mattermost, Inc. All Rights Reserved.\n See LICENSE.txt for license information."
+    ],
+    "id-blacklist": 0,
+    "indent": [
+      2,
+      4,
+      {
+        "SwitchCase": 0
+      }
+    ],
+    "jsx-quotes": [
+      2,
+      "prefer-single"
+    ],
+    "key-spacing": [
+      2,
+      {
+        "beforeColon": false,
+        "afterColon": true,
+        "mode": "strict"
+      }
+    ],
+    "keyword-spacing": [
+      2,
+      {
+        "before": true,
+        "after": true,
+        "overrides": {}
+      }
+    ],
+    "line-comment-position": 0,
+    "linebreak-style": 2,
+    "lines-around-comment": [
+      2,
+      {
+        "beforeBlockComment": true,
+        "beforeLineComment": true,
+        "allowBlockStart": true,
+        "allowBlockEnd": true
+      }
+    ],
+    "max-lines": [
+      1,
+      {
+        "max": 450,
+        "skipBlankLines": true,
+        "skipComments": false
+      }
+    ],
+    "max-nested-callbacks": [
+      2,
+      {
+        "max": 2
+      }
+    ],
+    "max-statements-per-line": [
+      2,
+      {
+        "max": 1
+      }
+    ],
+    "multiline-ternary": [
+      1,
+      "never"
+    ],
+    "new-cap": 2,
+    "new-parens": 2,
+    "newline-before-return": 0,
+    "newline-per-chained-call": 0,
+    "no-alert": 2,
+    "no-array-constructor": 2,
+    "no-await-in-loop": 2,
+    "no-caller": 2,
+    "no-case-declarations": 2,
+    "no-class-assign": 2,
+    "no-compare-neg-zero": 2,
+    "no-cond-assign": [
+      2,
+      "except-parens"
+    ],
+    "no-confusing-arrow": 2,
+    "no-console": 2,
+    "no-const-assign": 2,
+    "no-constant-condition": 2,
+    "no-debugger": 2,
+    "no-div-regex": 2,
+    "no-dupe-args": 2,
+    "no-dupe-class-members": 2,
+    "no-dupe-keys": 2,
+    "no-duplicate-case": 2,
+    "no-duplicate-imports": [
+      2,
+      {
+        "includeExports": true
+      }
+    ],
+    "no-else-return": 2,
+    "no-empty": 2,
+    "no-empty-function": 2,
+    "no-empty-pattern": 2,
+    "no-eval": 2,
+    "no-ex-assign": 2,
+    "no-extend-native": 2,
+    "no-extra-bind": 2,
+    "no-extra-label": 2,
+    "no-extra-parens": 0,
+    "no-extra-semi": 2,
+    "no-fallthrough": 2,
+    "no-floating-decimal": 2,
+    "no-func-assign": 2,
+    "no-global-assign": 2,
+    "no-implicit-coercion": 2,
+    "no-implicit-globals": 0,
+    "no-implied-eval": 2,
+    "no-inner-declarations": 0,
+    "no-invalid-regexp": 2,
+    "no-irregular-whitespace": 2,
+    "no-iterator": 2,
+    "no-labels": 2,
+    "no-lone-blocks": 2,
+    "no-lonely-if": 2,
+    "no-loop-func": 2,
+    "no-magic-numbers": 0,
+    "no-mixed-operators": [
+      2,
+      {
+        "allowSamePrecedence": false
+      }
+    ],
+    "no-mixed-spaces-and-tabs": 2,
+    "no-multi-assign": 2,
+    "no-multi-spaces": [
+      2,
+      {
+        "exceptions": {
+          "Property": false
+        }
+      }
+    ],
+    "no-multi-str": 0,
+    "no-multiple-empty-lines": [
+      2,
+      {
+        "max": 1
+      }
+    ],
+    "no-native-reassign": 2,
+    "no-negated-condition": 2,
+    "no-nested-ternary": 2,
+    "no-new": 2,
+    "no-new-func": 2,
+    "no-new-object": 2,
+    "no-new-symbol": 2,
+    "no-new-wrappers": 2,
+    "no-octal-escape": 2,
+    "no-param-reassign": 2,
+    "no-process-env": 2,
+    "no-process-exit": 2,
+    "no-proto": 2,
+    "no-prototype-builtins": 1,
+    "no-redeclare": 2,
+    "no-return-assign": [
+      2,
+      "always"
+    ],
+    "no-return-await": 2,
+    "no-script-url": 2,
+    "no-self-assign": [
+      2,
+      {
+        "props": true
+      }
+    ],
+    "no-self-compare": 2,
+    "no-sequences": 2,
+    "no-shadow": [
+      2,
+      {
+        "hoist": "functions"
+      }
+    ],
+    "no-shadow-restricted-names": 2,
+    "no-spaced-func": 2,
+    "no-tabs": 0,
+    "no-template-curly-in-string": 2,
+    "no-ternary": 0,
+    "no-this-before-super": 2,
+    "no-throw-literal": 2,
+    "no-trailing-spaces": [
+      2,
+      {
+        "skipBlankLines": false
+      }
+    ],
+    "no-undef-init": 2,
+    "no-undefined": 2,
+    "no-underscore-dangle": 2,
+    "no-unexpected-multiline": 2,
+    "no-unmodified-loop-condition": 2,
+    "no-unneeded-ternary": [
+      2,
+      {
+        "defaultAssignment": false
+      }
+    ],
+    "no-unreachable": 2,
+    "no-unsafe-finally": 2,
+    "no-unsafe-negation": 2,
+    "no-unused-expressions": 2,
+    "no-unused-vars": [
+      2,
+      {
+        "vars": "all",
+        "args": "after-used"
+      }
+    ],
+    "no-use-before-define": [
+      2,
+      {
+        "classes": false,
+        "functions": false,
+        "variables": false
+      }
+    ],
+    "no-useless-computed-key": 2,
+    "no-useless-concat": 2,
+    "no-useless-constructor": 2,
+    "no-useless-escape": 2,
+    "no-useless-rename": 2,
+    "no-useless-return": 2,
+    "no-var": 0,
+    "no-void": 2,
+    "no-warning-comments": 1,
+    "no-whitespace-before-property": 2,
+    "no-with": 2,
+    "object-curly-newline": 0,
+    "object-curly-spacing": [
+      2,
+      "never"
+    ],
+    "object-property-newline": [
+      2,
+      {
+        "allowMultiplePropertiesPerLine": true
+      }
+    ],
+    "object-shorthand": [
+      2,
+      "always"
+    ],
+    "one-var": [
+      2,
+      "never"
+    ],
+    "one-var-declaration-per-line": 0,
+    "operator-assignment": [
+      2,
+      "always"
+    ],
+    "operator-linebreak": [
+      2,
+      "after"
+    ],
+    "padded-blocks": [
+      2,
+      "never"
+    ],
+    "prefer-arrow-callback": 2,
+    "prefer-const": 2,
+    "prefer-destructuring": 0,
+    "prefer-numeric-literals": 2,
+    "prefer-promise-reject-errors": 2,
+    "prefer-rest-params": 2,
+    "prefer-spread": 2,
+    "prefer-template": 0,
+    "quote-props": [
+      2,
+      "as-needed"
+    ],
+    "quotes": [
+      2,
+      "single",
+      "avoid-escape"
+    ],
+    "radix": 2,
+    "require-yield": 2,
+    "rest-spread-spacing": [
+      2,
+      "never"
+    ],
+    "semi": [
+      2,
+      "always"
+    ],
+    "semi-spacing": [
+      2,
+      {
+        "before": false,
+        "after": true
+      }
+    ],
+    "sort-imports": 0,
+    "sort-keys": 0,
+    "space-before-blocks": [
+      2,
+      "always"
+    ],
+    "space-before-function-paren": [
+      2,
+      {
+        "anonymous": "never",
+        "named": "never",
+        "asyncArrow": "always"
+      }
+    ],
+    "space-in-parens": [
+      2,
+      "never"
+    ],
+    "space-infix-ops": 2,
+    "space-unary-ops": [
+      2,
+      {
+        "words": true,
+        "nonwords": false
+      }
+    ],
+    "symbol-description": 2,
+    "template-curly-spacing": [
+      2,
+      "never"
+    ],
+    "valid-typeof": [
+      2,
+      {
+        "requireStringLiterals": false
+      }
+    ],
+    "vars-on-top": 0,
+    "wrap-iife": [
+      2,
+      "outside"
+    ],
+    "wrap-regex": 2,
+    "yoda": [
+      2,
+      "never",
+      {
+        "exceptRange": false,
+        "onlyEquality": false
+      }
+    ],
+    "@typescript-eslint/array-type": [2, {"default": "array-simple"}],
+    "@typescript-eslint/member-delimiter-style": 2,
+    "@typescript-eslint/type-annotation-spacing": 2
+  },
+  "overrides": [
+    {
+      "files": ["*.test.js", "*.test.jsx", "*.test.ts", "*.test.tsx", "tests/**"],
+      "globals": {
+        "after": true,
+        "afterAll": true,
+        "afterEach": true,
+        "before": true,
+        "beforeAll": true,
+        "beforeEach": true,
+        "describe": true,
+        "expect": true,
+        "it": true,
+        "jest": true,
+        "test": true
+      },
+      "rules": {
+        "no-empty-function": 0,
+        "no-console": 0,
+        "max-nested-callbacks": 0,
+        "no-undefined": 0
+      }
+    }
+  ]
+}

webapp/platform/eslint-plugin/index.js

@@ -0,0 +1,21 @@
+"use strict";
+
+module.exports = {
+    configs: {
+        base: {
+            extends: [
+                require.resolve('./configs/.eslintrc.json'),
+            ],
+        },
+        react: {
+            extends: [
+                require.resolve('./configs/.eslintrc.json'),
+                require.resolve('./configs/.eslintrc-react.json'),
+            ],
+        },
+    },
+    rules: {
+        'no-dispatch-getstate': require('./rules/no-dispatch-getstate'),
+        'use-external-link': require('./rules/use-external-link'),
+    },
+};

webapp/platform/eslint-plugin/package.json

@@ -0,0 +1,28 @@
+{
+  "name": "@mattermost/eslint-plugin",
+  "version": "1.0.0",
+  "description": "ESLint configuration and custom rules used by Mattermost",
+  "repository": {
+    "type": "git",
+    "url": "git+https://github.com/mattermost/mattermost.git",
+    "directory": "webapp/platform/eslint-plugin"
+  },
+  "author": "Mattermost, Inc.",
+  "license": "Apache 2.0",
+  "homepage": "https://github.com/mattermost/mattermost/tree/master/webapp/platform/eslint-plugin#readme",
+  "main": "index.js",
+  "dependencies": {
+    "eslint-plugin-jsx-a11y": "^6.7.1",
+    "jsx-ast-utils": "^3.3.3"
+  },
+  "peerDependencies": {
+    "@typescript-eslint/eslint-plugin": "^5.57.1",
+    "eslint-plugin-header": "^3.1.1",
+    "eslint-plugin-react": "^7.32.2"
+  },
+  "peerDependenciesMeta": {
+    "eslint-plugin-react": {
+      "optional": true
+    }
+  }
+}

webapp/platform/eslint-plugin/rules/no-dispatch-getstate.js

@@ -0,0 +1,49 @@
+// Copyright (c) 2015-present Mattermost, Inc. All Rights Reserved.
+// See LICENSE.txt for license information.
+
+module.exports = {
+    meta: {
+        type: 'problem',
+        fixable: 'code',
+        messages: {
+            unexpected: 'Unexpected second argument passed to dispatch. getState does not need to be passed into dispatch.',
+        },
+    },
+    create(context) {
+        function checkDispatch(node) {
+            const args = node.arguments;
+            if (args.length === 2) {
+                context.report({
+                    node,
+                    messageId: 'unexpected',
+                    fix(fixer) {
+                        const sourceCode = context.getSourceCode();
+
+                        const before = sourceCode.getTokenBefore(args[1]);
+                        const after = sourceCode.getTokenAfter(args[1]);
+
+                        // Remove the getState argument and the preceding comma
+                        const fixes = [
+                            fixer.remove(before),
+                            fixer.remove(args[1]),
+                        ];
+
+                        // And remove the trailing comma if one exists
+                        if (after.type === 'Punctuator' && after.value === ',') {
+                            fixes.push(fixer.remove(after));
+                        }
+
+                        // Note that this sometimes mangles the whitespace slightly
+
+                        return fixes;
+                    },
+                });
+            }
+        }
+
+        return {
+            "CallExpression[callee.name='dispatch']": checkDispatch,
+            "CallExpression[callee.name='doDispatch']": checkDispatch,
+        };
+    },
+};

webapp/platform/eslint-plugin/rules/use-external-link.js

@@ -0,0 +1,43 @@
+// Copyright (c) 2015-present Mattermost, Inc. All Rights Reserved.
+// See LICENSE.txt for license information.
+
+const astUtils = require('jsx-ast-utils')
+const getElementType = require('eslint-plugin-jsx-a11y/lib/util/getElementType')
+
+module.exports =  {
+    meta: {
+        docs: {
+            description: 'Enforce all anchors with target="_blank" to use ExternalLink component',
+        },
+    },
+    create: (context) => {
+        const elementType = getElementType(context);
+        return {
+            JSXOpeningElement: (node) => {
+                const { attributes } = node;
+                const typeCheck = 'a';
+                const nodeType = elementType(node);
+                // Only check anchor elements
+                if (!nodeType || typeCheck !== nodeType) {
+                    return;
+                }
+
+                const propsToValidate = ['target'];
+                const values = propsToValidate.map((prop) => astUtils.getPropValue(astUtils.getProp(node.attributes, prop)));
+                // Checks if the target attribute is set to _blank (ie, is an external link)
+                const hasBlankTarget = values.some((value) => value != null && value === '_blank');
+
+                // When there is no target value at all, this rule does not apply:
+                if (!hasBlankTarget) {
+                    return;
+                }
+
+                context.report({
+                    node,
+                    message: 'Use ExternalLink component (components/external_link) for _blank target link-outs',
+                });
+                return
+            },
+        };
+    },
+};