High CPU usage while running a CRA with typescript in Windows.

[charlie632]

Is this a bug report?

Yes.

Did you try recovering your dependencies?

Yes.

Environment

Environment Info:                                                                                                                                                   System:                                                                           
 OS: Windows 10                                                                   
 CPU: (4) x64 Intel(R) Core(TM) i5-7200U CPU @ 2.50GHz                          
Binaries:                                                                          
Node: 10.15.3 - C:\Program Files\nodejs\node.EXE                                 
Yarn: 1.13.0 - C:\Program Files (x86)\Yarn\bin\yarn.CMD                          
npm: 6.9.0 - C:\Program Files\nodejs\npm.CMD                                   
                                          
npmPackages:                                                                       
react: Not Found                                                                 
react-dom: Not Found                                                             
  react-scripts: Not Found                                                       
npmGlobalPackages:                                                                
 create-react-app: Not Found
--

Details

I have a high CPU usage when running a React app.

I think it is a problem with a dependency, because if I run a newly created CRA --typescript, the CPU usage drastically decreases. My package.json is as follows:

{
  "name": "app-name",
  "version": "0.1.0",
  "private": true,
  "dependencies": {
    "@material-ui/core": "^4.0.0-beta.2",
    "@material-ui/icons": "^4.0.0-beta.0",
    "@material-ui/styles": "^4.0.0-beta.2",
    "@types/jest": "24.0.13",
    "@types/node": "12.0.1",
    "@types/react": "16.8.17",
    "@types/react-dom": "16.8.4",
    "apollo-boost": "^0.3.1",
    "apollo-link": "^1.2.11",
    "apollo-link-context": "^1.0.17",
    "apollo-link-error": "^1.1.10",
    "classnames": "^2.2.6",
    "graphql": "^14.3.0",
    "jwt-decode": "^2.2.0",
    "msal": "^1.0.0",
    "react": "^16.8.6",
    "react-apollo": "^2.5.5",
    "react-apollo-hooks": "^0.4.5",
    "react-dom": "^16.8.6",
    "react-router-dom": "^5.0.0",
    "react-scripts": "3.0.1",
    "typescript": "^3.4.5",
    "use-react-router": "^1.0.6"
  },
  "scripts": {
    "start": "react-scripts start",
    "build": "react-scripts build",
    "test": "react-scripts test",
    "eject": "react-scripts eject",
    "gen": "graphql-codegen --config codegen.yml",
    "storybook": "start-storybook -p 6006",
    "build-storybook": "build-storybook"
  },
  "eslintConfig": {
    "extends": "react-app"
  },
  "browserslist": {
    "production": [
      ">0.2%",
      "not dead",
      "not op_mini all"
    ],
    "development": [
      "last 1 chrome version",
      "last 1 firefox version",
      "last 1 safari version"
    ]
  },
  "devDependencies": {
    "@graphql-codegen/cli": "^1.1.3",
    "@graphql-codegen/typescript": "1.1.3",
    "@graphql-codegen/typescript-operations": "1.1.3",
    "@graphql-codegen/typescript-react-apollo": "1.1.3"
  }
}

Do you know if any of these packages is causing any issues?

I tried rewriting my App.tsx to render just an empty div and the CPU usage is still the same.

Tried deleting and installing node_modules, deleted typescript cache, but no luck.

Tried on a different Windows machine and the results are the same.

[charlie632]

UPDATE:

Switched to Ubuntu, same project, same package-lock.json - npm installed and no issues. Build times are faster than I could ever imagine. A friend tried in his 2014 Mac and runs perfectly.
So this is Windows related.

Any idea what module or package is occasioning this?

[charlie632]

Kept having the same issue on Ubuntu. Found out the solution (or workaround) to this. See #6792 for more details.

[ianschmitz]

Yes indeed it is likely related to TypeScript issues. Closing in favor of #6792.

microsoft/TypeScript#31048 is also related to #6792.