fix 'Duplicate string index signature' in ProcessEnv

[xiaoxiangmoe]

Fix Error:

TS2374: Duplicate string index signature.

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[Timer]

Can you provide a reproducing project please? This issue is not present for me.

[jonathaningram]

@Timer I am experiencing this too. If the OP doesn't provide a repro, I'll try to.

[Timer]

@jonathaningram can you give me a list of your files in src/? Not nested, just top level.

[jonathaningram]

@Timer

$ ls -la src/
total 160
drwxr-xr-x  23 jon  staff    736 31 Oct 09:25 .
drwxr-xr-x  18 jon  staff    576 31 Oct 08:28 ..
-rw-r--r--@  1 jon  staff   6148 15 Aug 13:33 .DS_Store
-rw-r--r--   1 jon  staff  10653 31 Oct 09:02 App.tsx
-rw-r--r--   1 jon  staff    894 17 Aug 08:48 DefaultLayout.tsx
-rw-r--r--   1 jon  staff    644 26 Sep 08:43 PrivateRoute.tsx
-rw-r--r--   1 jon  staff   1281 17 Aug 07:02 Routes.tsx
-rw-r--r--   1 jon  staff    174 21 Jun 17:13 UserContext.tsx
-rw-r--r--   1 jon  staff    900 18 Oct 08:45 auth.ts
drwxr-xr-x  22 jon  staff    704 31 Oct 09:00 components
-rw-r--r--   1 jon  staff    100 19 Jun 18:45 element-utils.ts
-rw-r--r--   1 jon  staff    690 17 Sep 08:46 errors.ts
-rw-r--r--   1 jon  staff    659 31 Oct 08:59 index.tsx
-rw-r--r--   1 jon  staff    685 14 Jun 08:17 job.ts
drwxr-xr-x  12 jon  staff    384 17 Aug 06:54 pages
drwxr-xr-x   4 jon  staff    128 11 May 17:16 proto
-rw-r--r--   1 jon  staff     40 31 Oct 09:25 react-app-env.d.ts
-rw-r--r--   1 jon  staff   1345  4 Jul 09:41 rpc.ts
-rw-r--r--   1 jon  staff    408 31 Oct 08:58 styled-components.ts
drwxr-xr-x  11 jon  staff    352 31 Oct 09:00 tenants
-rw-r--r--   1 jon  staff   1884 31 Oct 08:54 theme.ts
-rw-r--r--   1 jon  staff    121  9 Jul 09:10 url.ts

I also tried by removing react-app-env.d.ts and that didn't work either.

Removing [key: string]: string | undefined from node_modules/.../react-app.d.ts does fix the console error—not sure if it's the right way to fix it though but it makes the error go away...

Let me know if I can help any further.

[Timer]

Hmm, very interesting. I was looking for a legacy file in your source tree if you tried the beta, but it isn't present.

Can you please provide a minimal reproducing demo? That's the only way we're going to be able to figure this out.

So far, you two are the only experiencing this issue so I'd like to figure out what's unique about your setup.

[jonathaningram]

@Timer see https://github.com/jonathaningram/cra-5621

Per the above, if you remove [key: string]: string | undefined from node_modules/react-scripts/lib/react-app.d.ts it will compile.

Note: package.json contains a few (I suspect) unrelated deps. I didn't go as far as trying to remove each of those.

[xiaoxiangmoe]

@Timer

Reproducing Demo

yarn create react-app cra-app --typescript
cd cra-app

then close tsconfig.json's skipLibCheck from

{
  "compilerOptions": {
    "target": "es5",
    "allowJs": true,
    "skipLibCheck": true,

into

{
  "compilerOptions": {
    "target": "es5",
    "allowJs": true,
    "skipLibCheck":false,