ink! 4.0

[cmichi]

The Vision

With the next major release of ink! we strive to:

• implement all remaining breaking changes from our endeavor of reducing contract sizes (how the storage API works).
• Introduce a new metadata format to account for some of our current shortcomings (e.g. versioning).
• make ink! closer to the idiomatic way of Rust (by reverting transactions on Err returns from constructors).
• create tooling for testing cross-contract calls and testing against a custom runtime.
• improve the developer experience by bundling all ink! crates into one ink entrance crate.
• allow different contracts to reference and use the same event types.

We moved this point to 4.1:

• include first support for XCM and XCM testing.

The Plan

We're already in the middle of this. See the linked view.

Open Questions

If you want to help us out and contribute to this issue, in this section you can find open questions and tasks where we would appreciate any input.

Currently we don't have open questions.

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Here you can find the board with specific sub-tasks to this milestone: https://github.com/orgs/paritytech/projects/29/views/6

[forgetso]

Hi, can't wait to see cross contract testing. Where has the board for ink v4 gone? This link 404s https://github.com/orgs/paritytech/projects/30/views/2

[cmichi]

@forgetso It should all be on here: https://github.com/paritytech/ink/projects/8, the other one was an experiment which only existed for a short amount of time. I'm surprised that you even noticed it!

[cmichi]

Ah I get it now, the link to the board was in the GitHub description of this issue, I've updated it.

Hi, can't wait to see cross contract testing.

Yes, me too! How are you doing it right now? redspot + scripting?

[kvinwang]

Would the pallet-contracts running ink! 4.0 contracts can also run ink! 3.0 contracts?

[forgetso]

Thanks for the link!

Yes, me too! How are you doing it right now? redspot + scripting?

We are not currently testing cross contract calls although we would have used redspot, yes.

[stillonearth]

So cross-contact calls testing is scheduled for 4.0? Should one wait for it (if it's fairly close) or go with redspot?

[HCastano]

@stillonearth yes it's already working (albeit with some rough edges). For example, take a look at the contracts in lang-err-integration-tests for some examples on how to use it

[HCastano]

Closed via https://github.com/paritytech/ink/pull/1653 :shipit: