feat!: add predicates abigen

[hal3e]

This PR is is based on @mohammadfawaz sway branch which supports main function arguments for predicates.

We do not have to use the input_predicate_data(0) data anymore instead we pass the data directly into the main function. This is an example how a new predicate looks like:

predicate;

struct TestStruct {
    value: u64,
}

struct AnotherTestStruct {
    value: u64,
    number: u64,
}

fn main(test_struct: TestStruct, test_struct2: AnotherTestStruct) -> bool {
    test_struct.value == (test_struct2.value + test_struct2.number)
}

Previously, we could not useTestStruct or AnotherTestStruct directly in our test because it was not generated.
With the new abigen we generate all the types and we also generate an encoding function encode_data which has the same inputs as the predicate's main function...

This is how the new abigen is used:

    predicate_abigen!(
        MyPredicate,
        "packages/fuels/tests/predicates/predicate_structs/out/debug/predicate_structs-abi.json"
    );

    let predicate =
        MyPredicate::load_from("tests/predicates/predicate_structs/out/debug/predicate_structs.bin")?;

Send funds to a predicate:

    predicate
        .receive(&sender, amount, asset_id, None)
        .await?;

Spend funds from a predicate. First encode the data and then spend to a wallet:

    predicate
        .encode_data(
            TestStruct { value: 192 },
            AnotherTestStruct {
                value: 64,
                number: 128,
            },
        )
        .spend(&receiver, predicate_balance, asset_id, None)
        .await?;

What was done:

• Extend the Abigen to handle predicates and add the predicate abigen macro
  • Added AbigenType enum to specify if it is a contract, script or predicate
• Update the wallet's spend_predicate function to calculate the appropriate data offset for dynamic data
  • This means that we can use vectors as inputs in predicates
  • I moved the offset calculating function to fuels_core::offsets as it was used in fuels-signers and fuels-contract
• Added test for:
  • Coin and Message predicates
  • Primitive and custom type inputs
  • Generics and Vectors
• Update the docs

Breaking changes:

• Predicate instantiation
• Sending funds to and receiving funds from predicates

thanks @mohammadfawaz for the help from the compiler side!

[MujkicA]

Interface looks good IMO

[mohammadfawaz]

I'm assuming you need a new release of forc with my PR for this to get merged?

[hal3e]

I'm assuming you need a new release of forc with my PR for this to get merged?

Yes. Currently the CI is using your branch.

[digorithm]

I did a first pass focusing on the docs and interfaces. I thought I should publish the review without fully finishing it so you can work through the suggestions while I do another deeper pass!

By the way, it's looking beautiful!

[digorithm]

This is so good!

Consider this an approval, but since we have to wait for forc to be released so we can pin a released version, this is just a comment to prevent an accidental merge.

[segfault-magnet]

Excellent work. Especially with the bindings and the predicate data offset.

[Salka1988]

Awsome! 🏅

[digorithm]

LGTM -- wonderful work. These tests are 10/10.

[digorithm]