error TS2300: Duplicate identifier 'type' in Angular. while running ng build

### Version info

**Angular: 12.2.0**

**Firebase: 9.0.0**

**@angular/fire: 7.0.0**

**Error: node_modules/@firebase/auth-compat/dist/auth-compat/index.d.ts:53:10 - error TS2300: Duplicate identifier 'type'.**

`import { type User, type Unsubscribe, type ActionCodeInfo, type UserCredential, type Auth, type IdTokenResult, type MultiFactorError, type MultiFactorResolver, type PopupRedirectResolver, type Dependencies, type AuthCredential, type ApplicationVerifier, type ConfirmationResult, type AuthProvider, type MultiFactorUser, type NextOrObserver, type ErrorFn, type CompleteFn, type ActionCodeSettings, type Persistence, type PhoneAuthCredential } from "@firebase/auth";`

**My package.json**
`"dependencies": {
"@angular/animations": "^11.2.9",
"@angular/cdk": "^13.0.2",
"@angular/common": "~12.2.0",
"@angular/compiler": "~12.2.0",
"@angular/core": "~12.2.0",
"@angular/fire": "^7.2.0",
"@angular/forms": "~12.2.0",
"@angular/material": "^11.2.12",
"@angular/platform-browser": "~12.2.0",
"@angular/platform-browser-dynamic": "~12.2.0",
"@angular/router": "~12.2.0",
"@ng-bootstrap/ng-bootstrap": "^10.0.0",
"angularfire2": "^5.4.2",
"aws-sdk": "^2.1081.0",
"bootstrap": "^5.1.3",
"concurrently": "^6.2.1",
"cors": "^2.8.5",
"file-saver": "^2.0.5",
"firebase": "^9.4.1",
"http": "0.0.1-security",
"http-client": "^4.3.1",
"http-server": "^13.0.2",
"karma-chai": "^0.1.0",
"karma-mocha": "^2.0.1",
"karma-spec-reporter": "0.0.32",
"karma-viewport": "^1.0.8",
"mocha": "^9.1.1",
"ngx-toastr": "^14.1.4",
"rxjs": "~6.6.0",
"tslib": "^2.3.0",
"util": "^0.12.4",
"uuid-generator-ts": "^1.1.0",
"zone.js": "~0.11.4"
},
"devDependencies": {
"@angular-devkit/build-angular": "~12.2.6",
"@angular/cli": "~12.2.6",
"@angular/compiler-cli": "~12.2.0",
"@types/file-saver": "^2.0.5",
"@types/jasmine": "~3.8.0",
"@types/node": "^12.20.46",
"@types/uuid": "^8.3.4",
"jasmine-core": "~3.8.0",
"karma": "~6.3.0",
"karma-chrome-launcher": "~3.1.0",
"karma-coverage": "~2.0.3",
"karma-jasmine": "~4.0.0",
"karma-jasmine-html-reporter": "~1.7.0",
"typescript": "~4.3.5"
`
**My tsconfig.json**
`{
"compileOnSave": false,
"compilerOptions": {
"baseUrl": "./",
"outDir": "./dist/out-tsc",
"forceConsistentCasingInFileNames": true,
"strict": true,
"noImplicitReturns": true,
"noFallthroughCasesInSwitch": true,
"sourceMap": true,
"declaration": false,
"downlevelIteration": true,
"experimentalDecorators": true,
"moduleResolution": "node",
"importHelpers": true,
"target": "es2017",
"module": "es2020",
"lib": [
"es2018",
"dom"
]
},
"angularCompilerOptions": {
"enableI18nLegacyMessageIdFormat": false,
"strictInjectionParameters": true,
"strictInputAccessModifiers": true,
"strictTemplates": false
}
}`

after i **add skipLipCheck: true** in **tsconfig.json** file, i get below error.

`Error: node_modules/@firebase/auth-compat/dist/auth-compat/index.d.ts:53:421 - error TS1005: ',' expected.`

`import { type User, type Unsubscribe, type ActionCodeInfo, type UserCredential, type Auth, type IdTokenResult, type MultiFactorError, type MultiFactorResolver, type PopupRedirectResolver, type Dependencies, type AuthCredential, type ApplicationVerifier, type ConfirmationResult, type AuthProvider, type MultiFactorUser, type NextOrObserver, type ErrorFn, type CompleteFn, type ActionCodeSettings, type Persistence, type PhoneAuthCredential } from "@firebase/auth";`

How to fix this error?

先查看 package.json 和 tsconfig.json，然后运行 ng build，以复现来自 @firebase/auth-compat/dist/auth-compat/index.d.ts 的 TypeScript 错误。根据已报告的语法错误和重复标识符错误，检查 Angular、TypeScript、Firebase 和 @angular/fire 的版本；项目能够在没有这些错误的情况下构建即表示完成。

由索引模型根据 Issue 内容生成。