CheckAllAllocationFailuresExtraArgs

fn CheckAllAllocationFailuresExtraArgs(comptime TestFn: type) type {
    switch (@typeInfo(@typeInfo(TestFn).@"fn".return_type.?)) {
        .error_union => |info| {
            if (info.payload != void) {
                @compileError("Return type must be !void");
            }
        },
        else => @compileError("Return type must be !void"),
    }

    const ArgsTuple = std.meta.ArgsTuple(TestFn);

    const field_types = @typeInfo(ArgsTuple).@"struct".field_types;
    if (field_types.len == 0 or field_types[0] != std.mem.Allocator) {
        @compileError("The provided function must have an " ++ @typeName(std.mem.Allocator) ++ " as its first argument");
    }

    var extra_args: [field_types.len - 1]type = undefined;
    for (&extra_args, field_types[1..]) |*arg, field_type| {
        arg.* = field_type;
    }

    return @Tuple(&extra_args);
}