[Dropdown] Fix imports of types

[yash-thakur]

There was an issue in the latest version related to types which breaks typescript build for everyone.

• I have followed (at least) the PR section of the contributing guide.

[mui-bot]

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[michaldudak]

Can you describe the issue and provide a reproduction? I'd argue it "breaks typescript build for everyone" as our CI passes without errors.

[yash-thakur]

Hello @michaldudak

This is the issue that our entire team was facing after our CI/CD picked up the latest release.
I reverted the package to the previous version and all the issues were fixed. If you check the screenshot the import { type
should actually have been import type { to work correctly with the typescript compiler.

Let me know if you need any more information.

Thanks!

[oliviertassinari]

The PR looks correct https://www.typescriptlang.org/docs/handbook/modules.html#importing-types, as far as I understand it. We broke compatibility for TypeScript version <4.5, which goes against

Material UI requires a minimum version of TypeScript 3.5. This aims to match the policy of DefinitelyTyped, with the support of the versions of TypeScript that are less than two years old.

https://mui.com/material-ui/getting-started/supported-platforms/#typescript

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Material UI requires a minimum version of TypeScript 3.5.

@yash-thakur I'm curious, which MUI open-source project are you using? What's your TypeScript version?

[yash-thakur]

@oliviertassinari
I am using typescript version 4.5.5 and using @mui/material in my project.

[oliviertassinari]

Strange then, it should work for you https://devblogs.microsoft.com/typescript/announcing-typescript-4-5/#type-on-import-names (the release notes of TS are so great, they cover the problem well each time 😊).

[yash-thakur]

Then maybe because my system has overall tsc version as 4.4.4 which is <4.5 that causes the issue.

[michaldudak]

@yash-thakur Thanks for the details. Could you please update the PR to change only the problematic lines and leave the rest as before?

[michaldudak]

Thanks for working on this!