nordisk/monetize

crates/monetize-ui-server/tests/console_compiles.rs

//! The console must actually compile for the browser.
//!
//! `monetize-ui-web` is built for the browser and `cargo test --workspace`
//! builds it for the HOST. Its pure `fmt` tests do run there — that is measured,
//! not assumed — but a host build says nothing about whether the crate compiles
//! for `wasm32`, which is the only target the console is ever served from. So on
//! 2026-09-05 a change landed with **242 tests green** and a console that did
//! not compile at all: the operator would have got a blank page, and nothing in
//! the suite could have said so.
//!
//! (This paragraph used to claim the workspace run "never builds it" and that
//! the crate "cannot host tests". Both are false — `cargo test --workspace`
//! reports `fmt::tests::…` results from it. The hole is the TARGET, not the
//! crate, and stating it wrongly invites someone to close it in the wrong
//! place.)
//!
//! This guard closes that hole from the one crate that both ships the console
//! (`--ui-dir` serves its bundle) and can host a test.
//!
//! Two deliberate choices, both of which cost something:
//!
//! * It shells out to `cargo`. That is slower than a normal test and it
//!   contends on the target directory lock. The alternative is no coverage at
//!   all for the half of this product a human actually looks at, which is a
//!   worse trade. It uses a *separate* target dir so it cannot deadlock against
//!   the run that invoked it — the sibling repo has a flaky guard for exactly
//!   the reason this one avoids.
//! * **A missing `wasm32` target FAILS, it does not skip.** A guard that
//!   reports `ok` when it could not run is the shape that lets a real defect
//!   through wearing a green badge, and this repo has already been bitten by
//!   one of those in a sibling (`cli_matrix` reported `ok` whenever its binary
//!   was absent). Unmeasured is not a pass. If this fails on your machine,
//!   `rustup target add wasm32-unknown-unknown` — that is the fix, not a skip.

use std::path::PathBuf;
use std::process::Command;

fn workspace_root() -> PathBuf {
    // CARGO_MANIFEST_DIR is <root>/crates/monetize-ui-server
    PathBuf::from(env!("CARGO_MANIFEST_DIR"))
        .parent()
        .and_then(|p| p.parent())
        .expect("the manifest dir must sit two levels under the workspace root")
        .to_path_buf()
}

#[test]
fn the_console_compiles_for_the_browser() {
    let root = workspace_root();

    let installed = Command::new("rustup")
        .args(["target", "list", "--installed"])
        .output();
    match installed {
        Ok(out) if String::from_utf8_lossy(&out.stdout).contains("wasm32-unknown-unknown") => {}
        Ok(out) => panic!(
            "wasm32-unknown-unknown is not installed, so the console was NOT checked. \
             UNMEASURED IS NOT A PASS — run `rustup target add wasm32-unknown-unknown`. \
             installed targets: {}",
            String::from_utf8_lossy(&out.stdout).replace('\n', " ")
        ),
        Err(e) => panic!(
            "could not ask rustup which targets are installed ({e}), so the console was NOT \
             checked. UNMEASURED IS NOT A PASS."
        ),
    }

    let out = Command::new(env!("CARGO"))
        .current_dir(&root)
        .args([
            "check",
            "--quiet",
            "--target",
            "wasm32-unknown-unknown",
            "-p",
            "monetize-ui-web",
            // Its own directory, so this check cannot block on the lock held by
            // the very `cargo test` invocation that is running it.
            "--target-dir",
            "target/console-compile-guard",
        ])
        .output()
        .expect("cargo must be runnable");

    assert!(
        out.status.success(),
        "the console does not compile for wasm32, so the operator would be served a page that \
         cannot start. `cargo test --workspace` cannot see this on its own — that is why this \
         guard exists.\n--- cargo stderr ---\n{}",
        String::from_utf8_lossy(&out.stderr)
    );
}