gherkin.md

BDD Testing with Gherkin

DAO Contracts use the cucumber crate to run tests written in gherkin language.

Feature files are located in dao/tests/features directory. Test executables are located in dao/tests directory and need to be registered in the Cargo.toml file like this:

[[test]]
name = "test_bid_escrow"
harness = false  # allows Cucumber to print output instead of libtest
required-features = ["test-support"]

Running tests

To run the tests, for example for the test_bid_escrow executable, run the following command:

cargo odra test --test test_bid_escrow

To run the tests on the casper VM, execute:

cargo odra test -b --test test_bid_escrow

Writing tests

The executable file is pretty straightforward, here's a boilerplate used for the test_bid_escrow:

mod common;
mod steps;

use common::DaoWorld;
use cucumber::writer::Libtest;
use cucumber::World as _;

fn main() {
    let runner = DaoWorld::cucumber()
        .with_writer(Libtest::or_basic())
        .with_runner(cucumber_runner::SyncRunner::default())
        .run_and_exit("tests/features/bid_escrow/internal_worker.feature");
    futures::executor::block_on(runner);
}

Next, we need to describe in our code what each step in the feature file should do. This is done in files located in dao-contracts/tests/steps directory. For example, here's a code snippet explaining the cucumber what to do with the When InternalWorker submits the JobProof of Job 0 line from the feature file:

#[when(expr = "{account} submits the JobProof of Job {int}")]
fn submit_job_proof(w: &mut DaoWorld, worker: Account, job_id: JobId) {
    let worker = w.get_address(&worker);
    w.bid_escrow
        .as_account(worker)
        .submit_job_proof(job_id, DocumentHash::from("Job Proof"))
        .unwrap();
}

To learn more about cucumber, check out its documentation.