node: Make Buffer mergeable

[sandersn]

This allows packages that may or may not depend on node create a Buffer stub.

This will solve the current problem with dependents of @types/mongoose, which is deprecated but also broken on @types/node@16 because of the way it references global.Buffer. Even disregarding mongoose, a central class like Buffer should be declared in a mergeable way so that other packages can add to it in extenuating circumstances.

[typescript-bot]

@sandersn Thank you for submitting this PR!

This is a live comment which I will keep updated.

2 packages in this PR

• node — on npm, on unpkg
• safer-buffer — on npm, on unpkg

Code Reviews

Because this is a widely-used package, a DT maintainer will need to review it before it can be merged.

You can test the changes of this PR in the Playground.

Status

• ✅ No merge conflicts
• ❌ Continuous integration tests have failed
• 🕐 A DT maintainer needs to approve changes which affect more than one package

Once every item on this list is checked, I'll ask you for permission to merge and publish the changes.

---

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[typescript-bot]

🔔 @microsoft @DefinitelyTyped @jkomyno @alvis @r3nya @btoueg @smac89 @Touffy @DeividasBakanas @eyqs @Hannes-Magnusson-CK @KSXGitHub @hoo29 @kjin @ajafff @islishude @mwiktorczyk @mohsen1 @n-e @galkin @parambirs @eps1lon @SimonSchick @ThomasdenH @WilcoBakker @wwwy3y3 @samuela @kuehlein @bhongy @chyzwar @trivikr @nguymin4 @yoursunny @qwelias @ExE-Boss @Ryan-Willpower @peterblazejewicz @addaleax @JasonHK @victorperin @ZYSzys @ffflorian — please review this PR in the next few days. Be sure to explicitly select Approve or Request Changes in the GitHub UI so I know what's going on.

[typescript-bot]

@sandersn The CI build failed! Please review the logs for more information.

Once you've pushed the fixes, the build will automatically re-run. Thanks!

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[SimonSchick]

@sandersn any timeline for classes to be mergeable with other class declarations?

[peterblazejewicz]

I assume this will fix issues seen in the CI complaining about Buffer. I've seen this today on other failing PR not related to node directly

[sandersn]

@SimonSchick It's not something we've considered recently because it's possible today and not a common requirement.
Two problems:

1. Current TS never merges two values. (conveniently, namespaces are defined not to be values)
2. Current TS definitely never merges two block-scoped declarations.

@peterblazejewicz It should fix all the dependents of the deprecated @types/mongoose. I'm not sure about any others.

[typescript-bot]

@sandersn The CI build failed! Please review the logs for more information.

Once you've pushed the fixes, the build will automatically re-run. Thanks!

Note: builds which are failing do not end up on the list of PRs for the DT maintainers to review.

[sandersn]

@peterblazejewicz After some experimentation, I'm going to ship this as-is, so that it only fixes mongoose dependents. safer-buffer, for example, still fails with

ERROR: 1:1  no-outside-dependencies 
File /Users/nathanshively-sanders/DefinitelyTyped/node_modules/buffer/index.d.ts 
  comes from a `node_modules` but is not declared in this type's `package.json`. 

Because resolution of 'buffer' resolves not to the ambient module in DT/types/node/buffer.d.ts but the actual module in DT/node_modules/buffer/index.d.ts. It's likely that this will necessitate some other fix to buffer, but I want to at least get the mongoose dependents up and running again.

[typescript-bot]

I just published @types/[email protected] to npm.