Impl 0ary hostfns

[LucasGrasso]

Summary

Partially addresses #2653

• [n] y/n | Does it introduce breaking changes?
• [n] y/n | Is it dependent on a specific version of cargo-contract or pallet-revive?

Description

Implements the following host fns

• fn gas_price() -> u64
• fn call_data_size() -> u64
• fn return_data_size() -> u64
• fn ref_time_left() -> u64

[cmichi]

@LucasGrasso If you check the diff of this PR something is strange (see e.g. the changes to CHANGELOG.md). Maybe you need to update the master branch of your fork and then merge master into your branch.

[LucasGrasso]

@cmichi I think its ok now, my IDE autoformatted the changelog file, so I just copied and pasted the one in use-ink/ink/master.

[davidsemakula]

Thanks @LucasGrasso
A few notes/comments, but I'll let @cmichi have the last word.

Edit: Also, you can ignore the CI failure for the examples-test (2) job, it's unrelated to your changes.

[LucasGrasso]

@davidsemakula Thanks for your comments, implemented the changes you mentioned, they made sense to me. Can rollback if you want tho.

[davidsemakula]

@LucasGrasso RE: #2694 (comment)
Added as a suggestion for clarity 🙂

[cmichi]

I've left soft changes to the comments. Can you adapt the example contract + other functions to the same changes?

[LucasGrasso]

@cmichi done, added evm opcodes and modified comments of functions related to this pr and gas_limit.

[cmichi]

Thanks for the PR! Looks good besides the nits.

After applying them you'll most likely have to run cargo fmt locally, as the length of the line will be too long.

Use

cd ink/
fd Cargo.toml | xargs -n1 -I{} bash -c "echo {}; cargo +nightly fmt --manifest-path={}"  

to apply it through the codebase and all examples (which are not in the workspace).

[LucasGrasso]

Thanks for your help!

After applying them you'll most likely have to run cargo fmt locally, as the length of the line will be too long.

Applied suggestions and no further formatting changes where needed after running the script locally