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TypeError: Cannot assign to read only property 'jsx' of object '#<Object>'

See original GitHub issue

Describe the bug

When creating a react-typescript app using

npx create-react-app . --template typescript

The error:

yarn run v1.22.5
$ react-scripts start
/home/aditya/all/yt/twitter/node_modules/react-scripts/scripts/utils/verifyTypeScriptSetup.js:239
      appTsConfig.compilerOptions[option] = value;
                                          ^

TypeError: Cannot assign to read only property 'jsx' of object '#<Object>'
    at verifyTypeScriptSetup (/home/aditya/all/yt/twitter/node_modules/react-scripts/scripts/utils/verifyTypeScriptSetup.js:239:43)
    at Object.<anonymous> (/home/aditya/all/yt/twitter/node_modules/react-scripts/scripts/start.js:31:1)
    at Module._compile (internal/modules/cjs/loader.js:778:30)
    at Object.Module._extensions..js (internal/modules/cjs/loader.js:789:10)
    at Module.load (internal/modules/cjs/loader.js:653:32)
    at tryModuleLoad (internal/modules/cjs/loader.js:593:12)
    at Function.Module._load (internal/modules/cjs/loader.js:585:3)
    at Function.Module.runMain (internal/modules/cjs/loader.js:831:12)
    at startup (internal/bootstrap/node.js:283:19)
    at bootstrapNodeJSCore (internal/bootstrap/node.js:623:3)
error Command failed with exit code 1.
info Visit https://yarnpkg.com/en/docs/cli/run for documentation about this command.

Issue Analytics

State:
Created 3 years ago
Reactions:117
Comments:62 (2 by maintainers)

Top GitHub Comments

101reactions

jaquinocodecommented, Nov 20, 2020

Personally, I was able to fix this issue (this is on a fresh project) by: -changing the typescript version in package.json to “~4.0.5” -changing the value “jsx” in compilerOptions inside tsconfig.json to “react” instead of “react-jsx” -run npm install so that the older typescript version is installed -I don’t think this is needed but perhaps make sure vscode has the intellisense of ts set to the same or similar version to the one you’ve installed Mine is set to use the local one I just installed - 4.0.5 -I was then able to start the project normally with npm start

95reactions

bartlettpsjcommented, Nov 20, 2020

I just deleted tsconfig.json and ran yarn start, and it recreates it and runs (I did update to ts 4.0.5 too). But you have to delete everytime you run yarn start. i.e

rm tsconfig.json && yarn start

Hacky until we get a fix.

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