React 설치시 "babel-loader": "8.1.0" 오류

문제상황

here might be a problem with the project dependency tree.
It is likely not a bug in Create React App, but something you need to fix locally.

The react-scripts package provided by Create React App requires a dependency:

"babel-loader": "8.1.0"

Don't try to install it manually: your package manager does it automatically.
However, a different version of babel-eslint was detected higher up in the tree:

Users\username\node_modules\babel-loader (version: 8.2.2)

Manually installing incompatible versions is known to cause hard-to-debug issues.

If prefer to ignore this check, add SKIP_PREFLIGHT_CHECK=true to an .env file in your project.
That will permanently disable this message but you might encounter other issues.

To fix the dependency tree, try following the steps below in the exact order:

1. Delete package-lock.json (not package.json!) and/or yarn.lock in your project folder.
2. Delete node_modules in your project folder.
3. Remove "babel-eslint" from dependencies and/or devDependencies in the package.json file in your project folder.
4. Run npm install or yarn, depending on the package manager you use.

In most cases, this should be enough to fix the problem.
If this has not helped, there are a few other things you can try:

5. If you used npm, install yarn (http://yarnpkg.com/) and repeat the above steps with it instead.
This may help because npm has known issues with package hoisting which may get resolved in future versions.

6. Check if c:\Users\useranme\node_modules\babel-loader is outside your project directory.
For example, you might have accidentally installed something in your home folder.

7. Try running npm ls babel-eslint in your project folder.
This will tell you which other package (apart from the expected react-scripts) installed babel-eslint.

If nothing else helps, add SKIP_PREFLIGHT_CHECK=true to an .env file in your project.
That would permanently disable this preflight check in case you want to proceed anyway.

P.S. We know this message is long but please read the steps above :-) We hope you find them helpful!

해결방법1

.env 파일에
아래와 같이 저장하고 실행시키면 되십니다.
사전에 체크를 안하고 넘어가는 설정을 의미합니다.
하지만, 단순히 체크를 무시하는 것으로 결과적으로는 일단 문제 덮고 넘어가자는 의미로 궁극적인 해결책은 아닙니다.

SKIP_PREFLIGHT_CHECK=true

해결방법2

yarn이 babel-loader 버전 8.1.0을 확인할 수 있도록 package.json에 다음을 추가하십시오.

"resolutions": {
  "babel-loader": "8.1.0"
},

그런 다음 yarn install 을 실행하여 종속성을 새로 고치고 yarn.lock 파일을 업데이트하면, 되십니다.

해결방법3

위의 방법으로 해결이 안 될 수도 있는데
그런 경우 별도로 설치한 라이브러리도 없을 경우입니다.
별도로 설치한 적도 없는데 버전이 맞지 않는 다는 상황이라
위와 같은 방법으로 처리하여도 원인이 맞지 않아 당연히 해결이 안됩니다.

이와 같은 경우
프로젝트에서 내부에 있는 node_modules에서 라이브러리를 참조하지 않고 외부에 존재하는 라이브러리를 참조해서 그렇습니다.

global로 설치한 라이브러리가 충돌하는 것 같은데 충돌하는 라이브러리를 직접 찾아가서 삭제시켜주면 되십니다.