src/sys/pkg/tests/system-updater/src/epoch.rs

// Copyright 2021 The Fuchsia Authors. All rights reserved.
// Use of this source code is governed by a BSD-style license that can be
// found in the LICENSE file.

use {
    super::*,
    fidl_fuchsia_update_installer_ext::{PrepareFailureReason, State},
    pretty_assertions::assert_eq,
};

/// When epoch.json is in an unexpected format, we should expect to fail with the Internal reason.
#[fasync::run_singlethreaded(test)]
async fn invalid_epoch() {
    let env = TestEnv::builder().build();
    env.resolver
        .register_package("update", "upd4t3")
        .add_file("packages.json", make_packages_json([]))
        .add_file(
            "epoch.json",
            json!({
              "version": "1",
              // -1 is not a valid u64.
              "epoch": -1,
            })
            .to_string(),
        );

    let mut attempt = env.start_update().await.unwrap();

    assert_eq!(attempt.next().await.unwrap().unwrap(), State::Prepare);
    assert_eq!(
        attempt.next().await.unwrap().unwrap(),
        State::FailPrepare(PrepareFailureReason::Internal)
    );
}

// When target epoch < current epoch, we should fail with the UnsupportedDowngrade reason.
// Note: at this point, we can't yet integration test unsupported downgrades because the current
// epoch is zero and the target epoch in update package cannot be lower than zero. Once we bump the
// epoch, we can uncomment out this test.
// TODO(fxbug.dev/72117): use this test.
// ########################## BEGIN: CODE INTENTIONALLY COMMENTED OUT ##############################
// #[fasync::run_singlethreaded(test)]
// async fn unsupported_downgrade() {
//     let env = TestEnv::builder().build();
//     env.resolver
//         .register_package("update", "upd4t3")
//         .add_file("packages.json", make_packages_json([]))
//         .add_file("epoch.json", make_epoch_json(SOURCE_EPOCH - 1));

//     let mut attempt = env.start_update().await.unwrap();

//     assert_eq!(attempt.next().await.unwrap().unwrap(), State::Prepare);
//     assert_eq!(
//         attempt.next().await.unwrap().unwrap(),
//         State::FailPrepare(PrepareFailureReason::UnsupportedDowngrade)
//     );
// }
// ########################## END: CODE INTENTIONALLY COMMENTED OUT ################################