isolatedModules documentation still says that it bans non-modules

[DetachHead]

🔎 Search Terms

isolatedmodules 5.0

🕗 Version & Regression Information

• This changed between versions 4.9.5 and 5.0.4

⏯ Playground Link

• 5.3.0-dev.20230919 (no error)
• 4.9.5 (error)

💻 Code

const foo = 1

🙁 Actual behavior

no error

🙂 Expected behavior

'input.tsx' cannot be compiled under '--isolatedModules' because it is considered a global script file. Add an import, export, or an empty 'export {}' statement to make it a module.

Additional information about the issue

i noticed there's a new moduleDetection compiler option. is "moduleDetection": "force" supposed to replace this use case of isolatedModules? if so, i would expect the error to still appear unless the file is detected as a module

[MartinJohns]

This is intentional. See #46295 and linked issues. Used search terms: isolatedModules in:title

[DetachHead]

in that case, the isolatedModules documentation needs to be updated, because it still says this:

If isolatedModules is set, all implementation files must be modules (which means it has some form of import/export). An error occurs if any file isn’t a module

i always only used isolatedModules as a way to ban global scripts in my projects, i think many other people did the same, it's mentioned as a solution for this problem in many stackoverflow threads, eg:

https://stackoverflow.com/a/48360856
https://stackoverflow.com/a/56577324

so the updated documentation should probably also mention "moduleDetection": "force" as an alternative for this use case. seems like a pretty significant change that should have at least been mentioned in the 5.0 announcement post

[fatcerberus]

moduleDetection: "force" will cause the file to be detected as a module, for what it’s worth. It’s not really a direct replacement for banning global scripts per se, as it just prevents “this is a global script” from being detected at all - which IMO is better, since that’s how real module systems work anyway (i.e. script type is determined at load time and is not an intrinsic property of a JS file).

In other words: If you’re using isolatedModules today, you should keep using it in addition to moduleDetection: "force".