Turn on eslint in @firebase/database (#2429)

* auto fix some database lint issues with eslint

* fix more lint errors

* [AUTOMATED]: Prettier Code Styling

* run lint before test

* remove unnecessary eslint rules

* address comments

* fix some explicit any

* fix lint errors

* [AUTOMATED]: Prettier Code Styling

* [AUTOMATED]: License Headers

* [AUTOMATED]: Prettier Code Styling

* move comment location changed by prettier

* address comments

Author: Feiyang1

package.json

@@ -118,6 +118,7 @@
     "typescript": "3.7.3",
     "watch": "1.0.2",
     "webpack": "4.41.2",
-    "yargs": "15.0.2"
+    "yargs": "15.0.2",
+    "lodash": "4.17.15"
   }
 }

packages/database/.eslintrc.js

@@ -0,0 +1,18 @@
+module.exports = {
+  extends: '../../config/.eslintrc.js',
+  parserOptions: {
+    project: 'tsconfig.json',
+    // to make vscode-eslint work with monorepo
+    // https://github.com/typescript-eslint/typescript-eslint/issues/251#issuecomment-463943250
+    tsconfigRootDir: __dirname
+  },
+  rules: {
+    '@typescript-eslint/no-unused-vars': 'off',
+    '@typescript-eslint/no-floating-promises': 'off',
+    '@typescript-eslint/explicit-function-return-type': 'off',
+    'no-restricted-properties': 'off',
+    'no-restricted-globals': 'off',
+    'no-throw-literal': 'off',
+    'id-blacklist': 'off'
+  }
+};

packages/database/index.node.ts

@@ -74,7 +74,7 @@ export function initStandalone(app: FirebaseApp, url: string, version: string) {
     new Component(
       'auth-internal',
       // firebase-admin-node's app.INTERNAL implements FirebaseAuthInternal interface
-      // eslint-disable-next-line @eslint-tslint/no-explicit-any
+      // eslint-disable-next-line @typescript-eslint/no-explicit-any
       () => (app as any).INTERNAL,
       ComponentType.PRIVATE
     )
@@ -146,6 +146,7 @@ try {
   // Previously firebase-admin depends on @firebase/app, which causes version conflict on
   // @firebase/app when used together with the js sdk. More detail:
   // https://github.com/firebase/firebase-js-sdk/issues/1696#issuecomment-501546596
+  // eslint-disable-next-line import/no-extraneous-dependencies, @typescript-eslint/no-require-imports
   const firebase = require('@firebase/app').default;
   registerDatabase(firebase);
 } catch (err) {

packages/database/index.ts

@@ -14,7 +14,7 @@
  * See the License for the specific language governing permissions and
  * limitations under the License.
  */
-
+// eslint-disable-next-line import/no-extraneous-dependencies
 import firebase from '@firebase/app';
 import { FirebaseNamespace } from '@firebase/app-types';
 import { _FirebaseNamespace } from '@firebase/app-types/private';

packages/database/package.json

@@ -11,10 +11,12 @@
     "dist"
   ],
   "scripts": {
+    "lint": "eslint -c .eslintrc.js '**/*.ts' --ignore-path '../../.gitignore'",
+    "lint:fix": "eslint --fix -c .eslintrc.js '**/*.ts'  --ignore-path '../../.gitignore'",
     "build": "rollup -c",
     "dev": "rollup -c -w",
-    "test": "yarn test:emulator",
-    "test:all": "run-p test:browser test:node",
+    "test": "run-p lint test:emulator",
+    "test:all": "run-p lint test:browser test:node",
     "test:browser": "karma start --single-run",
     "test:node": "TS_NODE_FILES=true TS_NODE_CACHE=NO TS_NODE_COMPILER_OPTIONS='{\"module\":\"commonjs\"}' nyc --reporter lcovonly -- mocha 'test/{,!(browser)/**/}*.test.ts' --file index.node.ts --opts ../../config/mocha.node.opts",
     "test:emulator": "ts-node --compiler-options='{\"module\":\"commonjs\"}' ../../scripts/emulator-testing/database-test-runner.ts",

packages/database/src/api/DataSnapshot.ts

@@ -46,7 +46,7 @@ export class DataSnapshot {
    *
    * @return {*} JSON representation of the DataSnapshot contents, or null if empty.
    */
-  val(): any {
+  val(): unknown {
     validateArgCount('DataSnapshot.val', 0, 0, arguments.length);
     return this.node_.val();
   }
@@ -56,14 +56,14 @@ export class DataSnapshot {
    * the entire node contents.
    * @return {*} JSON representation of the DataSnapshot contents, or null if empty.
    */
-  exportVal(): any {
+  exportVal(): unknown {
     validateArgCount('DataSnapshot.exportVal', 0, 0, arguments.length);
     return this.node_.val(true);
   }
 
   // Do not create public documentation. This is intended to make JSON serialization work but is otherwise unnecessary
   // for end-users
-  toJSON(): any {
+  toJSON(): unknown {
     // Optional spacer argument is unnecessary because we're depending on recursion rather than stringifying the content
     validateArgCount('DataSnapshot.toJSON', 0, 1, arguments.length);
     return this.exportVal();
@@ -138,7 +138,9 @@ export class DataSnapshot {
     validateArgCount('DataSnapshot.forEach', 1, 1, arguments.length);
     validateCallback('DataSnapshot.forEach', 1, action, false);
 
-    if (this.node_.isLeafNode()) return false;
+    if (this.node_.isLeafNode()) {
+      return false;
+    }
 
     const childrenNode = this.node_ as ChildrenNode;
     // Sanitize the return value to a boolean. ChildrenNode.forEachChild has a weird return type...
@@ -156,8 +158,11 @@ export class DataSnapshot {
   hasChildren(): boolean {
     validateArgCount('DataSnapshot.hasChildren', 0, 0, arguments.length);
 
-    if (this.node_.isLeafNode()) return false;
-    else return !this.node_.isEmpty();
+    if (this.node_.isLeafNode()) {
+      return false;
+    } else {
+      return !this.node_.isEmpty();
+    }
   }
 
   get key() {

packages/database/src/api/Database.ts

@@ -73,13 +73,13 @@ export class Database implements FirebaseService {
   /**
    * Returns a reference to the root or to the path specified in the provided
    * argument.
-
+   *
    * @param {string|Reference=} path The relative string path or an existing
    * Reference to a database location.
    * @throws If a Reference is provided, throws if it does not belong to the
    * same project.
    * @return {!Reference} Firebase reference.
-   **/
+   */
   ref(path?: string): Reference;
   ref(path?: Reference): Reference;
   ref(path?: string | Reference): Reference {
@@ -109,14 +109,14 @@ export class Database implements FirebaseService {
     validateUrl(apiName, 1, parsedURL);
 
     const repoInfo = parsedURL.repoInfo;
-    if (repoInfo.host !== ((this.repo_ as any).repoInfo_ as RepoInfo).host) {
+    if (repoInfo.host !== (this.repo_.repoInfo_ as RepoInfo).host) {
       fatal(
         apiName +
           ': Host name does not match the current database: ' +
           '(found ' +
           repoInfo.host +
           ' but expected ' +
-          ((this.repo_ as any).repoInfo_ as RepoInfo).host +
+          (this.repo_.repoInfo_ as RepoInfo).host +
           ')'
       );
     }
@@ -153,10 +153,13 @@ export class DatabaseInternals {
 
   /** @return {Promise<void>} */
   async delete(): Promise<void> {
+    // eslint-disable-next-line @typescript-eslint/no-explicit-any
     (this.database as any).checkDeleted_('delete');
+    // eslint-disable-next-line @typescript-eslint/no-explicit-any
     RepoManager.getInstance().deleteRepo((this.database as any).repo_ as Repo);
-
+    // eslint-disable-next-line @typescript-eslint/no-explicit-any
     (this.database as any).repo_ = null;
+    // eslint-disable-next-line @typescript-eslint/no-explicit-any
     (this.database as any).root_ = null;
     this.database.INTERNAL = null;
     this.database = null;

packages/database/src/api/Query.ts

@@ -15,7 +15,14 @@
  * limitations under the License.
  */
 
-import { assert } from '@firebase/util';
+import {
+  assert,
+  errorPrefix,
+  validateArgCount,
+  validateCallback,
+  validateContextObject,
+  Deferred
+} from '@firebase/util';
 import { KEY_INDEX } from '../core/snap/indexes/KeyIndex';
 import { PRIORITY_INDEX } from '../core/snap/indexes/PriorityIndex';
 import { VALUE_INDEX } from '../core/snap/indexes/ValueIndex';
@@ -29,18 +36,13 @@ import {
   validateFirebaseDataArg,
   validateKey
 } from '../core/util/validation';
-import {
-  errorPrefix,
-  validateArgCount,
-  validateCallback,
-  validateContextObject
-} from '@firebase/util';
+
 import {
   ValueEventRegistration,
   ChildEventRegistration,
   EventRegistration
 } from '../core/view/EventRegistration';
-import { Deferred } from '@firebase/util';
+
 import { Repo } from '../core/Repo';
 import { QueryParams } from '../core/view/QueryParams';
 import { Reference } from './Reference';
@@ -49,7 +51,7 @@ import { DataSnapshot } from './DataSnapshot';
 let __referenceConstructor: new (repo: Repo, path: Path) => Query;
 
 export interface SnapshotCallback {
-  (a: DataSnapshot, b?: string | null): any;
+  (a: DataSnapshot, b?: string | null): unknown;
 }
 
 /**
@@ -99,15 +101,15 @@ export class Query {
         'or equalTo() must be a string.';
       if (params.hasStart()) {
         const startName = params.getIndexStartName();
-        if (startName != MIN_NAME) {
+        if (startName !== MIN_NAME) {
           throw new Error(tooManyArgsError);
         } else if (typeof startNode !== 'string') {
           throw new Error(wrongArgTypeError);
         }
       }
       if (params.hasEnd()) {
         const endName = params.getIndexEndName();
-        if (endName != MAX_NAME) {
+        if (endName !== MAX_NAME) {
           throw new Error(tooManyArgsError);
         } else if (typeof endNode !== 'string') {
           throw new Error(wrongArgTypeError);
@@ -198,8 +200,8 @@ export class Query {
   on(
     eventType: string,
     callback: SnapshotCallback,
-    cancelCallbackOrContext?: ((a: Error) => any) | Object | null,
-    context?: Object | null
+    cancelCallbackOrContext?: ((a: Error) => unknown) | object | null,
+    context?: object | null
   ): SnapshotCallback {
     validateArgCount('Query.on', 2, 4, arguments.length);
     validateEventType('Query.on', 1, eventType, false);
@@ -230,7 +232,7 @@ export class Query {
   protected onValueEvent(
     callback: (a: DataSnapshot) => void,
     cancelCallback: ((a: Error) => void) | null,
-    context: Object | null
+    context: object | null
   ) {
     const container = new ValueEventRegistration(
       callback,
@@ -248,8 +250,8 @@ export class Query {
    */
   onChildEvent(
     callbacks: { [k: string]: SnapshotCallback },
-    cancelCallback: ((a: Error) => any) | null,
-    context: Object | null
+    cancelCallback: ((a: Error) => unknown) | null,
+    context: object | null
   ) {
     const container = new ChildEventRegistration(
       callbacks,
@@ -267,7 +269,7 @@ export class Query {
   off(
     eventType?: string,
     callback?: SnapshotCallback,
-    context?: Object | null
+    context?: object | null
   ): void {
     validateArgCount('Query.off', 0, 3, arguments.length);
     validateEventType('Query.off', 1, eventType, true);
@@ -304,8 +306,8 @@ export class Query {
   once(
     eventType: string,
     userCallback?: SnapshotCallback,
-    failureCallbackOrContext?: ((a: Error) => void) | Object | null,
-    context?: Object | null
+    failureCallbackOrContext?: ((a: Error) => void) | object | null,
+    context?: object | null
   ): Promise<DataSnapshot> {
     validateArgCount('Query.once', 1, 4, arguments.length);
     validateEventType('Query.once', 1, eventType, false);
@@ -347,7 +349,9 @@ export class Query {
       /*cancel=*/ err => {
         this.off(eventType, onceCallback);
 
-        if (ret.cancel) ret.cancel.bind(ret.context)(err);
+        if (ret.cancel) {
+          ret.cancel.bind(ret.context)(err);
+        }
         deferred.reject(err);
       }
     );
@@ -591,7 +595,7 @@ export class Query {
    * An object representation of the query parameters used by this Query.
    * @return {!Object}
    */
-  queryObject(): Object {
+  queryObject(): object {
     return this.queryParams_.getQueryObject();
   }
 
@@ -635,12 +639,12 @@ export class Query {
    */
   private static getCancelAndContextArgs_(
     fnName: string,
-    cancelOrContext?: ((a: Error) => void) | Object | null,
-    context?: Object | null
-  ): { cancel: ((a: Error) => void) | null; context: Object | null } {
+    cancelOrContext?: ((a: Error) => void) | object | null,
+    context?: object | null
+  ): { cancel: ((a: Error) => void) | null; context: object | null } {
     const ret: {
       cancel: ((a: Error) => void) | null;
-      context: Object | null;
+      context: object | null;
     } = { cancel: null, context: null };
     if (cancelOrContext && context) {
       ret.cancel = cancelOrContext as (a: Error) => void;