061 phantom autodispose

// Test: Auto-discharge for phantom obligations
//
// Tests that the compiler automatically inserts cleanup
// when <allocated!> obligation is not manually discharged

~import std/io

const std = @import("std");

pub const Resource = struct {
    data: []const u8,
    allocator: std.mem.Allocator,
};

~pub event create-resource { name: []const u8 } -> *Resource<allocated!>

~proc create-resource|zig {
    const alloc = std.heap.page_allocator;
    const data = std.fmt.allocPrint(alloc, "Resource: {s}", .{name}) catch unreachable;
    const res = alloc.create(Resource) catch unreachable;
    res.* = .{ .data = data, .allocator = alloc };
    return res;
}

~pub event destroy-resource { res: *Resource<!allocated> }

~proc destroy-resource|zig {
    std.debug.print("  Auto-discharge called!\n", .{});
    res.allocator.free(res.data);
    std.heap.page_allocator.destroy(res);
}

// Helper to use the resource
~pub event use-resource { res: *Resource }

~proc use-resource|zig {
    std.debug.print("  Using: {s}\n", .{res.data});
}

// Test: Create resource, use it, but DON'T manually destroy
// Auto-discharge should insert destroy-resource
~std/io:print.ln("Test start")
~create-resource(name: "AutoDisposed"): r |> use-resource(res: r)
    // Obligation <allocated!> should trigger auto-discharge here

~std/io:print.ln("Test done")