ink! 3.0.0 RC 8

Version 3.0-rc8

This is the 8th release candidate for ink! 3.0.

Compatibility

You need to upgrade to a new version of the contracts pallet in order to use this
ink! release. Specifically we recommend you upgrade to at least the pallet version
249dbbb
(or newer than Jan 17, 2022).

For substrate-contracts-node we just issued a new release v0.5.0, which has been synchronized
to the latest Substrate master and hence is compatible with this ink! release candidate.

Also, the metadata changed with this release, so you need to have a recent version of
the user interface you are using. For polkadot-js/api and polkadot-js/apps the metadata
changes are supported since Jan 19, 2022.

Metadata Changes

There are two metadata changes in this release candidate:

For messages and constructors: name: Array ➔ label: String

The messages and constructors exposed by a contract were previously denoted with

"name": ["foo", "bar"]

Now they are instead denoted with

"label": "foo"

For public contract methods that are implemented from a trait, the trait name is prefixed to
the method name with :: as the separator. So e.g. trait_name::get_owner.

The ink! PR which implemented this is #923,
for the polkadot-js/api it was polkadot-js/api#4255.

Constructors got a new field: payable: bool

Constructors now have to be specified payable if it's intended for them to receive value
(i.e. tokens). This is a breaking change, beforehand they were by default payable,
now they are by default non-payable.

The ink! PR which implemented this is #1065, the PR that updated the ink!
metadata to V3 is #1100, and for the polkadot-js/api it was polkadot-js/api#4432.

Changed

• Update metadate to support payable constructors - #1100.
• Make constructors non-payable by default, require specifying payable explicitly - #1065.
• Renamed the error code EcdsaRecoverFailed to EcdsaRecoveryFailed ‒ #1064.
• Renamed the ink_env function transferred_balance() to transferred_value() ‒ #1063.
• Removed the error codes BelowSubsistenceThreshold and NewContractNotFunded ‒ #1062.
• Updated ink! to use the most recent contracts pallet API ‒ #1053.
• Explicitly link against rlibc to get non-buggy version of memcpy ‒ #1049.
• Changed the metadata field name to label for messages and constructors ‒ #923 (thanks @xgreenx).

Added

• Added a remove method to the Mapping data structure ‒ #1023.