[Typechain] generate types only for contracts and not test files

[ChristopherDedominici]

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Latest commit: e5d48d1

The changes in this PR will be included in the next version bump.

This PR includes changesets to release 2 packages

Name	Type
@nomicfoundation/hardhat-typechain	Patch
hardhat	Patch

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Name	Status	Preview	Comments	Updated (UTC)
hardhat	✅ Ready (Inspect)	Visit Preview	💬 Add feedback	Mar 4, 2025 3:41pm

[ChristopherDedominici]

Pato mentioned that probably this is the best place to add a hook that can emit the artifacts paths.
His message:
I think that we should change the moment when we generate the typechain types. Its now on build, but i believe it should be in cleanArtifacts. That already generates some typescript types for the artifacts. Especially when there are clashes between names. This would mean removing the hook, creating a new one after cleanupArtifacts, and using that one instead.

[galargh]

This would mean we generate types only when the entire project is compiled - see

hardhat/v-next/hardhat/src/internal/builtin-plugins/solidity/tasks/compile.ts

Line 37 in 4554b50

// If we recompiled the entire project we cleanup the artifacts

- which, as far as I understand, is not necessarily what we want.

To be fair, I also find hooking types generation to the cleanup step a little confusing. It is not obvious to know what the type generation has to do with cleanup without deeply understanding the internals. I think there might be some potential for the refactor in the cleanup function, but that's definitely out of the scope of this PR.

However, as far as when the type generation should get triggered, maybe it should be when the artifacts are emitted after all. But maybe we could add some option to the build and consequently emitArtifacts to control whether artifact declaration files -

hardhat/v-next/hardhat/src/internal/builtin-plugins/solidity/build-system/build-system.ts

Line 527 in 4554b50

const artifactsDeclarationFilePath = path.join(

- are emitted. Then, we could either propagate that option via the hook system or check whether the declaration file exists for a given artifact on the typechain side. There definitely might be better options, just thinking out loud.

[alcuadrado]

I think your points are valid, but would require further exploration, @galargh . I'd say we merge this PR and revaluate this soon.

One reason that can make the generation require clenup to be run is that you can have name clashes.

[ChristopherDedominici]

The old hook can be removed in favor of the new one. See previous comment for more details

[ChristopherDedominici]

I need a double check on this changeset, is this format acceptable for the v-next?