DeBridge Anchor Extensions

A utility crate that provides helpful extensions for the Anchor framework in Solana development.

Features

• AccountsCount: A trait that automatically calculates the number of accounts in Anchor account structs
• Macro support for deriving AccountsCount implementations

Usage

Basic Usage

use anchor_lang::prelude::*;
use debridge_anchor_extensions::AccountsCount;

#[derive(Accounts, AccountsCount)]
pub struct MyContext<'info> {
    pub account_info: AccountInfo<'info>,
    pub signer: Signer<'info>,
    pub system_program: Program<'info, System>,
}

The AccountsCount derive macro will automatically implement the AccountsCount trait for your struct, providing a constant ACCOUNTS_COUNT that represents the total number of accounts in the struct.

Nested Contexts

The AccountsCount trait automatically handles nested account contexts:

use anchor_lang::prelude::*;
use debridge_anchor_extensions::AccountsCount;

#[derive(Accounts, AccountsCount)]
pub struct ParentContext<'info> {
    pub signer: Signer<'info>,
    pub nested: ChildContext<'info>,
}

#[derive(Accounts, AccountsCount)]
pub struct ChildContext<'info> {
    pub system_program: Program<'info, System>,
    pub account: AccountInfo<'info>,
}

The ACCOUNTS_COUNT constant will include accounts from both the parent and child contexts.

Example

use anchor_lang::prelude::*;
use debridge_anchor_extensions::AccountsCount;

#[account]
pub struct AccountExample {
    pub foo: usize,
}

#[account(zero_copy)]
pub struct ZeroStruct {
    bar: usize,
}

#[derive(Accounts, AccountsCount)]
pub struct Context<'info> {
    account_info: AccountInfo<'info>,
    unchecked_account: UncheckedAccount<'info>,
    account_loader: AccountLoader<'info, ZeroStruct>,
    sysvar: Sysvar<'info, Rent>,
    account: Account<'info, AccountExample>,
    boxed: Box<Account<'info, AccountExample>>,
    program: Program<'info, System>,
    signer: Signer<'info>,
    system_account: SystemAccount<'info>,
}

// You can access the count using:
// Context::ACCOUNTS_COUNT

How it Works

The AccountsCount trait provides a simple interface:

pub trait AccountsCount {
    const ACCOUNTS_COUNT: usize;
}

The derive macro automatically implements this trait for your account structures, calculating the total number of accounts by:

• Counting each account field as 1
• Recursively adding the ACCOUNTS_COUNT of any nested account structures