The error for allowImportingTsExtensions does not reference rewriteRelativeImportExtensions

[fpapado]

🔎 Search Terms

• error TS5096
• allowImportingTsExtensions
• rewriteRelativeImportExtensions
• tsconfig
• diagnostics
• intellisense

🕗 Version & Regression Information

• This changed between versions N/A and 5.7.0-beta
• This changed in commit or PR Rewrite relative import extensions with flag #59767
• This is the behavior in every version I tried, and I reviewed the FAQ for entries for allowImportingTsExtensions and rewriteRelativeImportExtensions
• I was unable to test this on prior versions because it was only introduced in 5.7

⏯ Playground Link

No response

💻 Code

tsconfig.json with diagnostic error:

{
  "compilerOptions": {
    "module": "Node16",
    "moduleResolution": "Node16",
    "allowImportingTsExtensions": true,
  }
}

🙁 Actual behavior

When specifying allowImportingTsExtensions as above, I get an error, as intended:

tsconfig.json:5:35 - error TS5096: Option 'allowImportingTsExtensions' can only be used when either 'noEmit' or 'emitDeclarationOnly' is set.

However, if I add "rewriteRelativeImportExtensions": true to the same tsconfig, the error goes away, which is contrary to the error message.

The behavior seems correct, but the error message seems incomplete or inconsistent.

---

At the same time, intellisense for allowImportingTsExtensions in VSCode reports:

Allow imports to include TypeScript file extensions. Requires '--moduleResolution bundler' and either '--noEmit' or '--emitDeclarationOnly' to be set.

This is only mentioned as a requirement in intellisense, but not in the error message.

🙂 Expected behavior

I would expect the message to reference rewriteRelativeImportExtensions as one of the conditions that allow for allowImportingTsExtensions.

I am not sure whether --moduleResolution bundler is required, but at least unifying the intellisense and diagnostic would be good.

The combination of factors seems to be "noEmit or emitDeclarationOnly or rewriteRelativeImportExtensions", but I am not sure what the exact new diagnostic message should be 😅

(I don't mean to be nitpicky! I tend to learn best from intellisense and the diagnostics errors, so I was on the lookout for them when trying out the 5.7.0-beta and rewriteRelativeImportExtensions 😌)

Additional information about the issue

No response

[KurtGokhan]

I couldn't find a working configuration for using rewriteRelativeImportExtensions and allowImportingTsExtensions together. I want tsc to emit, and rewrite .ts to .js. But the LSP errors on me when I add allowImportingTsExtensions: true to my tsconfig. Also rewriteRelativeImportExtensions isn't allowed in tsconfig, which doesn't make sense.

Edit: My bad. rewriteRelativeImportExtensions is allowed in tsconfig. VSCode was using 5.6 and it confused me.

[zanminkian]

Addition: rewriteRelativeImportExtensions can exist in tsconfig.json, but official document does not mention it.