ERROR: No 'ink_lang' dependency found

Question

On master branch after merged this PR, I try to build example contract and got this error. Has anyone faced this issue?

Answer 1

cargo install cargo-contract --version 2.0.0-rc

The above command will install v2 of cargo contract. This includes ink v4 which has renamed the ink_lang module to ink. Thus using cargo-contract before v2 results in the ink_lang not found error. Other changes have also been made for ink v4, such as ink_env becoming ink::env, so you will need to make the corresponding changes throughout your contract. Here's a link to the cargo-contract v2 release. And here's a link to ink v4's release, which lists the breaking changes.

Answer 2

It's because of cargo-contract branch hasn't merged and which is in progress, you can view details here

Answer 3

This version of cargo-contract solved it for me:

cargo install cargo-contract --version 2.0.0-beta