init

pub fn init(ws: *Build.WebServer) Allocator.Error!Fuzz {
    const gpa = ws.gpa;

    const run_steps: []const *Step.Run = steps: {
        var steps: std.ArrayListUnmanaged(*Step.Run) = .empty;
        defer steps.deinit(gpa);
        const rebuild_node = ws.root_prog_node.start("Rebuilding Unit Tests", 0);
        defer rebuild_node.end();
        var rebuild_wg: std.Thread.WaitGroup = .{};
        defer rebuild_wg.wait();

        for (ws.all_steps) |step| {
            const run = step.cast(Step.Run) orelse continue;
            if (run.producer == null) continue;
            if (run.fuzz_tests.items.len == 0) continue;
            try steps.append(gpa, run);
            ws.thread_pool.spawnWg(&rebuild_wg, rebuildTestsWorkerRun, .{ run, gpa, ws.ttyconf, rebuild_node });
        }

        if (steps.items.len == 0) fatal("no fuzz tests found", .{});
        rebuild_node.setEstimatedTotalItems(steps.items.len);
        break :steps try gpa.dupe(*Step.Run, steps.items);
    };
    errdefer gpa.free(run_steps);

    for (run_steps) |run| {
        assert(run.fuzz_tests.items.len > 0);
        if (run.rebuilt_executable == null)
            fatal("one or more unit tests failed to be rebuilt in fuzz mode", .{});
    }

    return .{
        .ws = ws,
        .run_steps = run_steps,
        .wait_group = .{},
        .prog_node = .none,
        .coverage_files = .empty,
        .coverage_mutex = .{},
        .queue_mutex = .{},
        .queue_cond = .{},
        .msg_queue = .empty,
    };
}