integration-tests.md

How to write integration tests for an extension

Make a test crate inside the extension folder. As an example, here is the structure of the rv32im-extension-test crate:

extensions/rv32im/tests/
├── Cargo.toml
├── src
│   └── lib.rs
├── programs
│   └── Cargo.toml
│   └── examples
│       └── example1.rs
│       └── example2.rs
│       └── ...

The examples folder contains the test programs in rust.

fibonacci.rs example:

#![cfg_attr(not(feature = "std"), no_main)]
#![cfg_attr(not(feature = "std"), no_std)]

openvm::entry!(main);

pub fn main() {
    let n = core::hint::black_box(1 << 10);
    let mut a: u32 = 0;
    let mut b: u32 = 1;
    for _ in 1..n {
        let sum = a + b;
        a = b;
        b = sum;
    }
    if a == 0 {
        panic!();
    }
}

And then to transpile, run, and prove the above program, in the src/lib.rs file, you can do:

#[test]
fn test_fibonacci_prove() -> Result<()> {
    let elf = build_example_program_at_path(get_programs_dir!(), "fibonacci")?;
    let exe = VmExe::from_elf(
        elf,
        Transpiler::<F>::default()
            .with_extension(Rv32ITranspilerExtension)
            .with_extension(Rv32MTranspilerExtension)
            .with_extension(Rv32IoTranspilerExtension),
    )?;
    let config = Rv32IConfig::default();
    air_test(config, exe, vec![]);
    Ok(())
}

Note: If the crate with example is not in ./programs, specify the relative path with get_programs_dir!("path to the programs crate").