Function test_map_operator_bracket_access

tests/test_container_helpers.h:1010–1025

// Verifies: operator[] allows modification through iterator dereferencing
template<template<typename, typename> class MapTemplate>
void test_map_operator_bracket_access() {
    using MapContainer = MapTemplate<int, fl::shared_ptr<int>>;

    MapContainer m;
    auto original = make_shared_int(111);
    populate_map(m, 1, original);

    // Verify value through operator[]
    FL_CHECK(*m[1] == 111);

    // Modify through iterator
    auto it = m.find(1);
    FL_CHECK(it != m.end());
    it->second = make_shared_int(222);
    FL_CHECK(*m[1] == 222);
}

// Test iteration order (for sorted maps)
// Verifies: elements are visited in key order