Creating new app with typescript template giving an error on yarn start

[ericdsw]

Describe the bug

I was trying to create a new react app using typescript, but I ran into an issue when trying to run it. I ran the npx create-react-app just_testing --template typescript and everything installed correctly, but when I ran yarn start to test it I got the following error:

TypeScript error in /Users/ericdesedas/Development/projects/javascript/just_testing_2/node_modules/@types/testing-library__react/node_modules/pretty-format/build/index.d.ts(7,13):
'=' expected. TS1005

 5 | * LICENSE file in the root directory of this source tree.
 6 | */
 > 7 | import type * as PrettyFormat from './types';
 | ^
 8 | /**
 9 | * Returns a presentation string of your `val` object
 10 | * @param val any potential JavaScript object

Did you try recovering your dependencies?

yarn version: 1.22.4
npm version: 6.13.7

Environment

This is what I get when I run npx create-react-app --info:

Environment Info:

 current version of create-react-app: 3.4.1
 running from /Users/ericdesedas/.config/yarn/global/node_modules/create-react-app

 System:
 OS: macOS 10.15.3
 CPU: (4) x64 Intel(R) Core(TM) i5-6360U CPU @ 2.00GHz
 Binaries:
 Node: 13.9.0 - ~/.nvm/versions/node/v13.9.0/bin/node
 Yarn: 1.22.4 - /usr/local/bin/yarn
 npm: 6.13.7 - ~/.nvm/versions/node/v13.9.0/bin/npm
 Browsers:
 Chrome: 80.0.3987.149
 Firefox: Not Found
 Safari: 13.0.5
 npmPackages:
 react: ^16.13.1 => 16.13.1
 react-dom: ^16.13.1 => 16.13.1
 react-scripts: 3.4.1 => 3.4.1
 npmGlobalPackages:
 create-react-app: Not Found

Steps to reproduce

It appears that creating a new react app with typescript is installing a dependency with some kind of release error.

1. Run npx create-react-app my_app --template typescript
2. Wait for the installation to finish
3. Run yarn start and watch the error in PrettyFormat.

Note: I also tried to run yarn create react-app just_testing --typescript`, but the error kept showing up.

Expected behavior

I assumed that a brand new react app should be able to run without issue.

Actual behavior

The only output I got is what I showed as the error in a previous section, both in the terminal and in the browser.

Reproducible demo

N/A

[alexandreramosdev]

I have the same problem

[existentialism]

It's due to pretty-format@25.2.0 (part of jest) relying on TS 3.8 syntax.

Ref: #8714, #8717, and #8713

[SarthakThakur0097]

So are there any fixes for it currently or do we have to wait for the FB team to fix this?

[zunsakai]

same problem ...

[programateus]

After creating the application, just update typedcript with npm update typescript

[luiza177]

I had the same problem with npm start. Will try mateusbds' solution.

[ericdsw]

Yeah, running yarn upgrade --latest seems to fix the problem as well.

[luiza177]

Can also confirm runningnpm update typescript fixes the problem.

[stale]

This issue has been automatically marked as stale because it has not had any recent activity. It will be closed in 5 days if no further activity occurs.

[stale]

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