Use new eslint package- fix lint issues in ts and js

.eslintrc.js

@@ -11,111 +11,35 @@ const path = require('path');
 const matrixJsSdkPath = path.join(path.dirname(require.resolve('matrix-js-sdk')), '..');
 
 module.exports = {
+    extends: ["matrix-org", "matrix-org/react-legacy"],
     parser: "babel-eslint",
-    extends: [matrixJsSdkPath + "/.eslintrc.js"],
-    plugins: [
-      "react",
-      "react-hooks",
-      "flowtype",
-      "babel"
-    ],
+
+    env: {
+        browser: true,
+        node: true,
+    },
     globals: {
         LANGUAGES_FILE: "readonly",
     },
-    env: {
-        es6: true,
-    },
-    parserOptions: {
-        ecmaFeatures: {
-            jsx: true,
-            legacyDecorators: true,
-        }
-    },
     rules: {
-        // eslint's built in no-invalid-this rule breaks with class properties
-        "no-invalid-this": "off",
-        // so we replace it with a version that is class property aware
-        "babel/no-invalid-this": "error",
-
-        // We appear to follow this most of the time, so let's enforce it instead
-        // of occasionally following it (or catching it in review)
-        "keyword-spacing": "error",
-
-        /** react **/
-        // This just uses the react plugin to help eslint known when
-        // variables have been used in JSX
-        "react/jsx-uses-vars": "error",
-        // Don't mark React as unused if we're using JSX
-        "react/jsx-uses-react": "error",
-
-        // bind or arrow function in props causes performance issues
-        // (but we currently use them in some places)
-        // It's disabled here, but we should using it sparingly.
-        "react/jsx-no-bind": "off",
-        "react/jsx-key": ["error"],
-
-        // Components in JSX should always be defined.
-        "react/jsx-no-undef": "error",
-
-        // Assert no spacing in JSX curly brackets
-        // <Element prop={ consideredError} prop={notConsideredError} />
-        //
-        // https://github.com/yannickcr/eslint-plugin-react/blob/HEAD/docs/rules/jsx-curly-spacing.md
-        //
-        // Disabled for now - if anything we'd like to *enforce* spacing in JSX
-        // curly brackets for legibility, but in practice it's not clear that the
-        // consistency particularly improves legibility here. --Matthew
-        //
-        // "react/jsx-curly-spacing": ["error", {"when": "never", "children": {"when": "always"}}],
-
-        // Assert spacing before self-closing JSX tags, and no spacing before or
-        // after the closing slash, and no spacing after the opening bracket of
-        // the opening tag or closing tag.
-        //
-        // https://github.com/yannickcr/eslint-plugin-react/blob/HEAD/docs/rules/jsx-tag-spacing.md
-        "react/jsx-tag-spacing": ["error"],
-
-        /** flowtype **/
-        "flowtype/require-parameter-type": ["warn", {
-            "excludeArrowFunctions": true,
-        }],
-        "flowtype/define-flow-type": "warn",
-        "flowtype/require-return-type": ["warn",
-            "always",
-            {
-              "annotateUndefined": "never",
-              "excludeArrowFunctions": true,
-            }
-        ],
-        "flowtype/space-after-type-colon": ["warn", "always"],
-        "flowtype/space-before-type-colon": ["warn", "never"],
-
-        /*
-         * things that are errors in the js-sdk config that the current
-         * code does not adhere to, turned down to warn
-         */
-        "max-len": ["warn", {
-            // apparently people believe the length limit shouldn't apply
-            // to JSX.
-            ignorePattern: '^\\s*<',
-            ignoreComments: true,
-            ignoreRegExpLiterals: true,
-            code: 120,
-        }],
-        "valid-jsdoc": ["warn"],
-        "new-cap": ["warn"],
-        "key-spacing": ["warn"],
-        "prefer-const": ["warn"],
-
-        // crashes currently: https://github.com/eslint/eslint/issues/6274
-        "generator-star-spacing": "off",
-
-        "react-hooks/rules-of-hooks": "error",
-        "react-hooks/exhaustive-deps": "warn",
-    },
-    settings: {
-        flowtype: {
-            onlyFilesWithFlowAnnotation: true
-        },
+        // Things we do that break the ideal style
+        "no-constant-condition": "off",
+        "prefer-promise-reject-errors": "off",
+        "no-async-promise-executor": "off",
+        "quotes": "off",
+        "indent": "off",
     },
+
+    overrides: [{
+        files: ["src/**/*.{ts, tsx}"],
+        "extends": ["matrix-org/ts"],
+        "rules": {
+            // We disable this while we're transitioning
+            "@typescript-eslint/no-explicit-any": "off",
+            // We'd rather not do this but we do
+            "@typescript-eslint/ban-ts-comment": "off",
+
+            "quotes": "off",
+        }
+    }],
 };