dynsethash.cc

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/*
                          Aleph_w
 
  Data structures & Algorithms
  version 2.0.0b
  https://github.com/lrleon/Aleph-w
 
  This file is part of Aleph-w library
 
  Copyright (c) 2002-2026 Leandro Rabindranath Leon
 
  Permission is hereby granted, free of charge, to any person obtaining a copy
  of this software and associated documentation files (the "Software"), to deal
  in the Software without restriction, including without limitation the rights
  to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
  copies of the Software, and to permit persons to whom the Software is
  furnished to do so, subject to the following conditions:
 
  The above copyright notice and this permission notice shall be included in all
  copies or substantial portions of the Software.
 
  THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
  IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
  FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
  AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
  LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
  OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
  SOFTWARE.
*/
 
 
#include <algorithm>
#include <stdexcept>
#include <vector>
#include <string>
#include <gtest/gtest.h>
 
#include <tpl_dynSetHash.H>
 
using namespace std;
using namespace Aleph;
 
// ============================================================================
// Basic Operations Tests - DynHashTable
// ============================================================================
 
TEST(DynHashTable, EmptyTableProperties)
{
  DynSetLhash<int> table;
 
  EXPECT_TRUE(table.is_empty());
  EXPECT_EQ(table.size(), 0u);
  EXPECT_FALSE(table.contains(42));
  EXPECT_EQ(table.search(42), nullptr);
  EXPECT_FALSE(table.has(42));
}
 
TEST(DynHashTable, InsertSingleElement)
{
  DynSetLhash<int> table;
 
  auto * p = table.insert(42);
  ASSERT_NE(p, nullptr);
  EXPECT_EQ(*p, 42);
  EXPECT_FALSE(table.is_empty());
  EXPECT_EQ(table.size(), 1u);
  EXPECT_TRUE(table.contains(42));
  EXPECT_TRUE(table.has(42));
}
 
TEST(DynHashTable, InsertMultipleElements)
{
  DynSetLhash<int> table;
 
  for (int i : {5, 3, 7, 1, 9, 2, 8})
    {
      auto * p = table.insert(i);
      ASSERT_NE(p, nullptr);
      EXPECT_EQ(*p, i);
    }
 
  EXPECT_EQ(table.size(), 7u);
 
  for (int i : {1, 2, 3, 5, 7, 8, 9})
    EXPECT_TRUE(table.contains(i));
 
  EXPECT_FALSE(table.contains(4));
  EXPECT_FALSE(table.contains(6));
}
 
TEST(DynHashTable, InsertRejectsDuplicates)
{
  DynSetLhash<int> table;
 
  auto * p1 = table.insert(42);
  ASSERT_NE(p1, nullptr);
  EXPECT_EQ(*p1, 42);
  EXPECT_EQ(table.size(), 1u);
 
  auto * p2 = table.insert(42);
  EXPECT_EQ(p2, nullptr);  // Duplicate rejected
  EXPECT_EQ(table.size(), 1u);  // Size unchanged
}
 
TEST(DynHashTable, SearchFindsExistingKey)
{
  DynSetLhash<int> table;
 
  table.insert(10);
  table.insert(20);
  table.insert(30);
 
  auto * p = table.search(20);
  ASSERT_NE(p, nullptr);
  EXPECT_EQ(*p, 20);
}
 
TEST(DynHashTable, SearchReturnsNullForMissingKey)
{
  DynSetLhash<int> table;
 
  table.insert(10);
  table.insert(30);
 
  EXPECT_EQ(table.search(20), nullptr);
}
 
TEST(DynHashTable, FindReturnsReference)
{
  DynSetLhash<int> table;
 
  table.insert(42);
 
  const auto & key = table.find(42);
  EXPECT_EQ(key, 42);
 
  // Non-const version returns modifiable reference
  auto & key2 = table.find(42);
  EXPECT_EQ(key2, 42);
 
  // WARNING: Modifying a key through the reference breaks the hash table invariants!
  // The key is stored at hash(42)'s bucket, but if we change it to 99,
  // it won't be found at hash(99)'s bucket. This is UNDEFINED BEHAVIOR.
  // So we just verify that find() returns a non-const reference without actually modifying it.
}
 
TEST(DynHashTable, FindThrowsIfNotFound)
{
  DynSetLhash<int> table;
 
  table.insert(10);
 
  EXPECT_THROW(table.find(42), domain_error);
}
 
// ============================================================================
// Insert Variations Tests
// ============================================================================
 
TEST(DynHashTable, SearchOrInsertBehavior)
{
  DynSetLhash<int> table;
 
  // First call: inserts
  auto * p1 = table.search_or_insert(42);
  ASSERT_NE(p1, nullptr);
  EXPECT_EQ(*p1, 42);
  EXPECT_EQ(table.size(), 1u);
 
  // Second call: returns existing
  auto * p2 = table.search_or_insert(42);
  ASSERT_NE(p2, nullptr);
  EXPECT_EQ(*p2, 42);
  EXPECT_EQ(table.size(), 1u);  // Size unchanged
  EXPECT_EQ(p1, p2);  // Same pointer
}
 
TEST(DynHashTable, ContainsOrInsertBehavior)
{
  DynSetLhash<int> table;
 
  // First call: inserts, returns {ptr, false}
  auto [p1, found1] = table.contains_or_insert(42);
  ASSERT_NE(p1, nullptr);
  EXPECT_EQ(*p1, 42);
  EXPECT_FALSE(found1);  // Was inserted
  EXPECT_EQ(table.size(), 1u);
 
  // Second call: finds, returns {ptr, true}
  auto [p2, found2] = table.contains_or_insert(42);
  ASSERT_NE(p2, nullptr);
  EXPECT_EQ(*p2, 42);
  EXPECT_TRUE(found2);  // Already existed
  EXPECT_EQ(table.size(), 1u);
  EXPECT_EQ(p1, p2);  // Same pointer
}
 
TEST(DynHashTable, AddAndAppendAliases)
{
  DynSetLhash<int> table;
 
  auto * p1 = table.add(10);
  ASSERT_NE(p1, nullptr);
  EXPECT_EQ(*p1, 10);
 
  auto * p2 = table.append(20);
  ASSERT_NE(p2, nullptr);
  EXPECT_EQ(*p2, 20);
 
  EXPECT_EQ(table.size(), 2u);
}
 
TEST(DynHashTable, MoveInsert)
{
  DynSetLhash<string> table;
 
  string s = "hello";
  auto * p = table.insert(std::move(s));
  ASSERT_NE(p, nullptr);
  EXPECT_EQ(*p, "hello");
  // s should be in moved-from state (typically empty, but not guaranteed)
}
 
// ============================================================================
// Remove Tests
// ============================================================================
 
TEST(DynHashTable, RemoveByKey)
{
  DynSetLhash<int> table;
 
  table.insert(10);
  table.insert(20);
  table.insert(30);
 
  int removed = table.remove(20);
  EXPECT_EQ(removed, 20);
  EXPECT_EQ(table.size(), 2u);
  EXPECT_FALSE(table.contains(20));
  EXPECT_TRUE(table.contains(10));
  EXPECT_TRUE(table.contains(30));
}
 
TEST(DynHashTable, RemoveThrowsIfNotFound)
{
  DynSetLhash<int> table;
 
  table.insert(10);
 
  EXPECT_THROW(table.remove(42), domain_error);
}
 
TEST(DynHashTable, RemoveByPointer)
{
  DynSetLhash<int> table;
 
  table.insert(10);
  auto * p20 = table.insert(20);
  table.insert(30);
 
  ASSERT_NE(p20, nullptr);
 
  // Remove by pointer
  table.remove(p20);
 
  EXPECT_EQ(table.size(), 2u);
  EXPECT_FALSE(table.contains(20));
  EXPECT_TRUE(table.contains(10));
  EXPECT_TRUE(table.contains(30));
}
 
TEST(DynHashTable, RemoveAllElements)
{
  DynSetLhash<int> table;
 
  for (int i = 0; i < 50; ++i)
    table.insert(i);
 
  EXPECT_EQ(table.size(), 50u);
 
  for (int i = 0; i < 50; ++i)
    table.remove(i);
 
  EXPECT_TRUE(table.is_empty());
  EXPECT_EQ(table.size(), 0u);
}
 
TEST(DynHashTable, EmptyMethod)
{
  DynSetLhash<int> table;
 
  for (int i = 0; i < 100; ++i)
    table.insert(i);
 
  EXPECT_EQ(table.size(), 100u);
 
  table.empty();
 
  EXPECT_TRUE(table.is_empty());
  EXPECT_EQ(table.size(), 0u);
 
  table.insert(1);
  table.clear();
  EXPECT_TRUE(table.is_empty());
}
 
// ============================================================================
// Copy/Move Semantics Tests
// ============================================================================
 
TEST(DynHashTable, CopyConstructor)
{
  DynSetLhash<int> table1;
 
  for (int i : {1, 2, 3, 4, 5})
    table1.insert(i);
 
  DynSetLhash<int> table2(table1);
 
  EXPECT_EQ(table2.size(), 5u);
  for (int i : {1, 2, 3, 4, 5})
    EXPECT_TRUE(table2.contains(i));
 
  // Verify independence
  table1.remove(3);
  EXPECT_FALSE(table1.contains(3));
  EXPECT_TRUE(table2.contains(3));
}
 
TEST(DynHashTable, CopyAssignment)
{
  DynSetLhash<int> table1, table2;
 
  for (int i : {1, 2, 3})
    table1.insert(i);
 
  for (int i : {10, 20})
    table2.insert(i);
 
  table2 = table1;
 
  EXPECT_EQ(table2.size(), 3u);
  for (int i : {1, 2, 3})
    EXPECT_TRUE(table2.contains(i));
  EXPECT_FALSE(table2.contains(10));
  EXPECT_FALSE(table2.contains(20));
}
 
TEST(DynHashTable, SelfAssignment)
{
  DynSetLhash<int> table;
 
  for (int i : {1, 2, 3})
    table.insert(i);
 
  table = table;
 
  EXPECT_EQ(table.size(), 3u);
  for (int i : {1, 2, 3})
    EXPECT_TRUE(table.contains(i));
}
 
TEST(DynHashTable, MoveConstructor)
{
  DynSetLhash<int> table1;
 
  for (int i : {1, 2, 3, 4, 5})
    table1.insert(i);
 
  DynSetLhash<int> table2(std::move(table1));
 
  EXPECT_EQ(table2.size(), 5u);
  for (int i : {1, 2, 3, 4, 5})
    EXPECT_TRUE(table2.contains(i));
 
  EXPECT_TRUE(table1.is_empty());
}
 
TEST(DynHashTable, MoveAssignment)
{
  DynSetLhash<int> table1, table2;
 
  for (int i : {1, 2, 3})
    table1.insert(i);
 
  for (int i : {10, 20})
    table2.insert(i);
 
  table2 = std::move(table1);
 
  EXPECT_EQ(table2.size(), 3u);
  for (int i : {1, 2, 3})
    EXPECT_TRUE(table2.contains(i));
 
  // After fix: Move assignment should leave table1 empty
  EXPECT_TRUE(table1.is_empty());
  EXPECT_EQ(table1.size(), 0u);
}
 
TEST(DynHashTable, Swap)
{
  DynSetLhash<int> table1, table2;
 
  for (int i : {1, 2, 3})
    table1.insert(i);
 
  for (int i : {10, 20})
    table2.insert(i);
 
  table1.swap(table2);
 
  EXPECT_EQ(table1.size(), 2u);
  EXPECT_TRUE(table1.contains(10));
  EXPECT_TRUE(table1.contains(20));
 
  EXPECT_EQ(table2.size(), 3u);
  EXPECT_TRUE(table2.contains(1));
  EXPECT_TRUE(table2.contains(2));
  EXPECT_TRUE(table2.contains(3));
}
 
// ============================================================================
// Iterator Tests
// ============================================================================
 
TEST(DynHashTable, IteratorEmptyTable)
{
  DynSetLhash<int> table;
 
  DynSetLhash<int>::Iterator it(table);
  EXPECT_FALSE(it.has_curr());
}
 
TEST(DynHashTable, IteratorTraversal)
{
  DynSetLhash<int> table;
 
  for (int i : {5, 3, 7, 1, 9})
    table.insert(i);
 
  vector<int> keys;
  for (DynSetLhash<int>::Iterator it(table); it.has_curr(); it.next_ne())
    keys.push_back(it.get_curr());
 
  EXPECT_EQ(keys.size(), 5u);
 
  // Hash table doesn't guarantee order, just verify all keys present
  sort(keys.begin(), keys.end());
  vector<int> expected = {1, 3, 5, 7, 9};
  EXPECT_EQ(keys, expected);
}
 
TEST(DynHashTable, IteratorDel)
{
  DynSetLhash<int> table;
 
  for (int i : {1, 2, 3, 4, 5})
    table.insert(i);
 
  DynSetLhash<int>::Iterator it(table);
  ASSERT_TRUE(it.has_curr());
 
  int first = it.get_curr();
  it.del();
 
  EXPECT_EQ(table.size(), 4u);
  EXPECT_FALSE(table.contains(first));
}
 
TEST(DynHashTable, GetFirstAndLast)
{
  DynSetLhash<int> table;
 
  table.insert(10);
  table.insert(20);
  table.insert(30);
 
  // Just verify they don't throw
  EXPECT_NO_THROW(table.get_first());
  EXPECT_NO_THROW(table.get_last());
}
 
// ============================================================================
// String Keys Tests
// ============================================================================
 
TEST(DynHashTable, StringKeys)
{
  DynSetLhash<string> table;
 
  table.insert("apple");
  table.insert("banana");
  table.insert("cherry");
 
  EXPECT_EQ(table.size(), 3u);
  EXPECT_TRUE(table.contains("apple"));
  EXPECT_TRUE(table.contains("banana"));
  EXPECT_FALSE(table.contains("date"));
}
 
// ============================================================================
// Stress Tests
// ============================================================================
 
TEST(DynHashTable, LargeNumberOfInsertions)
{
  DynSetLhash<int> table;
 
  // Insert 10000 elements
  for (int i = 0; i < 10000; ++i)
    table.insert(i);
 
  EXPECT_EQ(table.size(), 10000u);
 
  // Verify all present
  for (int i = 0; i < 10000; ++i)
    EXPECT_TRUE(table.contains(i));
}
 
TEST(DynHashTable, ManyCollisions)
{
  // Custom hash that always returns same value -> forces collisions
  auto bad_hash = [](const int &) -> size_t { return 42; };
 
  DynSetLhash<int> table(100, bad_hash);
 
  for (int i = 0; i < 100; ++i)
    table.insert(i);
 
  EXPECT_EQ(table.size(), 100u);
 
  for (int i = 0; i < 100; ++i)
    EXPECT_TRUE(table.contains(i));
}
 
TEST(DynHashTable, RandomInsertRemove)
{
  DynSetLhash<int> table;
  vector<int> inserted;
 
  // Random insertions
  for (int i = 0; i < 500; ++i)
    {
      if (int key = rand() % 1000; table.insert(key) != nullptr)
        inserted.push_back(key);
    }
 
  // Verify all inserted keys are present
  for (int key : inserted)
    EXPECT_TRUE(table.contains(key));
 
  EXPECT_EQ(table.size(), inserted.size());
 
  // Random removals
  for (size_t i = 0; i < inserted.size() / 2; ++i)
    {
      int idx = rand() % inserted.size();
      table.remove(inserted[idx]);
      inserted.erase(inserted.begin() + idx);
    }
 
  EXPECT_EQ(table.size(), inserted.size());
  for (int key : inserted)
    EXPECT_TRUE(table.contains(key));
}
 
TEST(DynHashTable, RehashingBehavior)
{
  DynSetLhash<int> table(10);  // Start small
 
  // Insert many elements to force rehashing
  for (int i = 0; i < 1000; ++i)
    table.insert(i);
 
  EXPECT_EQ(table.size(), 1000u);
 
  // Verify all still accessible
  for (int i = 0; i < 1000; ++i)
    EXPECT_TRUE(table.contains(i));
 
  // Remove many to trigger shrinking
  for (int i = 0; i < 950; ++i)
    table.remove(i);
 
  EXPECT_EQ(table.size(), 50u);
 
  for (int i = 950; i < 1000; ++i)
    EXPECT_TRUE(table.contains(i));
}
 
// ============================================================================
// DynMapHashTable Tests
// ============================================================================
 
TEST(DynMapHashTable, EmptyMapProperties)
{
  DynMapHash<int, string> map;
 
  EXPECT_TRUE(map.is_empty());
  EXPECT_EQ(map.size(), 0u);
  EXPECT_FALSE(map.contains(42));
  EXPECT_EQ(map.search(42), nullptr);
}
 
TEST(DynMapHashTable, InsertPair)
{
  DynMapHash<int, string> map;
 
  auto * p = map.insert(1, "one");
  ASSERT_NE(p, nullptr);
  EXPECT_EQ(p->first, 1);
  EXPECT_EQ(p->second, "one");
  EXPECT_EQ(map.size(), 1u);
}
 
TEST(DynMapHashTable, InsertMultiplePairs)
{
  DynMapHash<int, string> map;
 
  map.insert(1, "one");
  map.insert(2, "two");
  map.insert(3, "three");
 
  EXPECT_EQ(map.size(), 3u);
  EXPECT_TRUE(map.contains(1));
  EXPECT_TRUE(map.contains(2));
  EXPECT_TRUE(map.contains(3));
}
 
TEST(DynMapHashTable, InsertRejectsDuplicateKeys)
{
  DynMapHash<int, string> map;
 
  auto * p1 = map.insert(1, "one");
  ASSERT_NE(p1, nullptr);
 
  auto * p2 = map.insert(1, "uno");
  EXPECT_EQ(p2, nullptr);  // Duplicate key rejected
  EXPECT_EQ(map.size(), 1u);
 
  // Original value unchanged
  EXPECT_EQ(map.find(1), "one");
}
 
TEST(DynMapHashTable, SearchByKey)
{
  DynMapHash<int, string> map;
 
  map.insert(1, "one");
  map.insert(2, "two");
 
  auto * p = map.search(2);
  ASSERT_NE(p, nullptr);
  EXPECT_EQ(p->first, 2);
  EXPECT_EQ(p->second, "two");
 
  EXPECT_EQ(map.search(99), nullptr);
}
 
TEST(DynMapHashTable, FindByKey)
{
  DynMapHash<int, string> map;
 
  map.insert(1, "one");
 
  EXPECT_EQ(map.find(1), "one");
  EXPECT_THROW(map.find(99), domain_error);
}
 
TEST(DynMapHashTable, OperatorBracketInsert)
{
  DynMapHash<int, string> map;
 
  // Non-const operator[] inserts if key doesn't exist
  map[1] = "one";
  EXPECT_EQ(map.size(), 1u);
  EXPECT_EQ(map[1], "one");
 
  // Can modify existing
  map[1] = "uno";
  EXPECT_EQ(map[1], "uno");
  EXPECT_EQ(map.size(), 1u);
}
 
TEST(DynMapHashTable, OperatorBracketConstThrows)
{
  DynMapHash<int, string> map;
  map.insert(1, "one");
 
  const auto & const_map = map;
  EXPECT_EQ(const_map[1], "one");
  EXPECT_THROW(const_map[99], domain_error);
}
 
TEST(DynMapHashTable, RemoveByKey)
{
  DynMapHash<int, string> map;
 
  map.insert(1, "one");
  map.insert(2, "two");
  map.insert(3, "three");
 
  string removed = map.remove(2);
  EXPECT_EQ(removed, "two");
  EXPECT_EQ(map.size(), 2u);
  EXPECT_FALSE(map.contains(2));
 
  map.clear();
  EXPECT_TRUE(map.is_empty());
  EXPECT_EQ(map.size(), 0u);
}
 
TEST(DynMapHashTable, Keys)
{
  DynMapHash<int, string> map;
 
  map.insert(1, "one");
  map.insert(2, "two");
  map.insert(3, "three");
 
  auto keys = map.keys();
  EXPECT_EQ(keys.size(), 3u);
 
  vector<int> sorted_keys;
  keys.for_each([&sorted_keys](int k) { sorted_keys.push_back(k); });
  sort(sorted_keys.begin(), sorted_keys.end());
 
  vector<int> expected = {1, 2, 3};
  EXPECT_EQ(sorted_keys, expected);
}
 
// BUG: tpl_dynSetHash.H line 540 has wrong return type (DynList<Key> instead of DynList<Data>)
// This test is disabled until the bug is fixed in the library
// The values() method should return DynList<Data> but currently returns DynList<Key>
TEST(DynMapHashTable, DISABLED_Values)
{
  // Test disabled due to bug in library implementation
  GTEST_SKIP() << "values() has wrong return type in tpl_dynSetHash.H:540";
}
 
TEST(DynMapHashTable, ValuesPtr)
{
  DynMapHash<int, string> map;
 
  map.insert(1, "one");
  map.insert(2, "two");
 
  auto ptrs = map.values_ptr();
  EXPECT_EQ(ptrs.size(), 2u);
 
  // Modify through pointer
  ptrs.for_each([](string * p) {
    if (*p == "one")
      *p = "ONE";
  });
 
  EXPECT_EQ(map.find(1), "ONE");
}
 
TEST(DynMapHashTable, ItemsPtr)
{
  DynMapHash<int, string> map;
 
  map.insert(1, "one");
  map.insert(2, "two");
 
  auto items = map.items_ptr();
  EXPECT_EQ(items.size(), 2u);
}
 
TEST(DynMapHashTable, MoveSemantics)
{
  DynMapHash<int, string> map;
 
  string s = "hello";
  map.insert(1, std::move(s));
  EXPECT_EQ(map.find(1), "hello");
 
  int k = 2;
  map.insert(std::move(k), "world");
  EXPECT_EQ(map.find(2), "world");
}
 
// ============================================================================
// Free Functions Tests (join, intercept, unique, repeated)
// ============================================================================
 
TEST(DynHashTableFunctions, Join)
{
  DynList<int> l1 = {1, 2, 3, 4};
  DynList<int> l2 = {3, 4, 5, 6};
 
  auto result = join(l1, l2);
 
  // Result should be union: {1, 2, 3, 4, 5, 6}
  EXPECT_EQ(result.size(), 6u);
 
  DynSetLhash<int> result_set(result);
  for (int i : {1, 2, 3, 4, 5, 6})
    EXPECT_TRUE(result_set.contains(i));
}
 
TEST(DynHashTableFunctions, Intercept)
{
  DynList<int> l1 = {1, 2, 3, 4, 5};
  DynList<int> l2 = {3, 4, 5, 6, 7};
 
  auto result = intercept(l1, l2);
 
  // Result should be intersection: {3, 4, 5}
  EXPECT_EQ(result.size(), 3u);
 
  vector<int> vec;
  result.for_each([&vec](int i) { vec.push_back(i); });
  sort(vec.begin(), vec.end());
 
  vector<int> expected = {3, 4, 5};
  EXPECT_EQ(vec, expected);
}
 
TEST(DynHashTableFunctions, Unique)
{
  DynList<int> l = {1, 2, 2, 3, 3, 3, 4, 4, 4, 4};
 
  auto result = unique(l);
 
  // Result should be {1, 2, 3, 4}
  EXPECT_EQ(result.size(), 4u);
 
  DynSetLhash<int> result_set(result);
  for (int i : {1, 2, 3, 4})
    EXPECT_TRUE(result_set.contains(i));
}
 
TEST(DynHashTableFunctions, Repeated)
{
  DynList<int> l = {1, 2, 2, 3, 3, 3, 4, 5};
 
  auto result = repeated(l);
 
  // Result contains all occurrences of duplicated values
  // The function returns ALL instances of keys that appear more than once
  // So we get 3 elements: one 2 (at index 2), and two 3s (at indices 3 and 4)
  EXPECT_GE(result.size(), 2u);  // At least 2 and 3 are duplicated
 
  DynSetLhash<int> result_set(result);
  EXPECT_TRUE(result_set.contains(2));
  EXPECT_TRUE(result_set.contains(3));
  EXPECT_FALSE(result_set.contains(1));  // 1 only appears once
  EXPECT_FALSE(result_set.contains(4));  // 4 only appears once
  EXPECT_FALSE(result_set.contains(5));  // 5 only appears once
}
 
TEST(DynHashTableFunctions, RepeatedWithIndex)
{
  DynList<int> l = {1, 2, 2, 3, 4, 3};
 
  auto result = repeated_with_index(l);
 
  // Result should be: {(2, 2), (3, 5)}
  EXPECT_EQ(result.size(), 2u);
 
  bool found_2 = false, found_3 = false;
  result.for_each([&](const pair<int, size_t> & p) {
    if (p.first == 2)
      {
        EXPECT_EQ(p.second, 2u);
        found_2 = true;
      }
    if (p.first == 3)
      {
        EXPECT_EQ(p.second, 5u);
        found_3 = true;
      }
  });
 
  EXPECT_TRUE(found_2);
  EXPECT_TRUE(found_3);
}
 
// ============================================================================
// Different Hash Table Types Tests
// ============================================================================
 
TEST(DynHashTable, LinearHashTableBasics)
{
  DynSetLinHash<int> table;
 
  for (int i : {1, 2, 3, 4, 5})
    table.insert(i);
 
  EXPECT_EQ(table.size(), 5u);
  for (int i : {1, 2, 3, 4, 5})
    EXPECT_TRUE(table.contains(i));
}
 
TEST(DynHashTable, DynSetHashAlias)
{
  DynSetHash<int> table;
 
  for (int i : {10, 20, 30})
    table.insert(i);
 
  EXPECT_EQ(table.size(), 3u);
  EXPECT_TRUE(table.contains(20));
}
 
// ============================================================================
// Edge Cases
// ============================================================================
 
TEST(DynHashTable, SingleElement)
{
  DynSetLhash<int> table;
 
  table.insert(42);
 
  EXPECT_EQ(table.size(), 1u);
  EXPECT_TRUE(table.contains(42));
 
  table.remove(42);
  EXPECT_TRUE(table.is_empty());
}
 
TEST(DynHashTable, InsertRemoveRepeated)
{
  DynSetLhash<int> table;
 
  for (int cycle = 0; cycle < 10; ++cycle)
    {
      for (int i = 0; i < 50; ++i)
        table.insert(i);
 
      EXPECT_EQ(table.size(), 50u);
 
      for (int i = 0; i < 50; ++i)
        table.remove(i);
 
      EXPECT_TRUE(table.is_empty());
    }
}
 
TEST(DynHashTable, CustomHashFunction)
{
  // Custom hash: just return the value modulo 100
  auto custom_hash = [](const int & k) -> size_t { return k % 100; };
 
  DynSetLhash<int> table(100, custom_hash);
 
  table.insert(1);
  table.insert(101);
  table.insert(201);
 
  EXPECT_EQ(table.size(), 3u);
  EXPECT_TRUE(table.contains(1));
  EXPECT_TRUE(table.contains(101));
  EXPECT_TRUE(table.contains(201));
}
 
// ============================================================================
// Custom Types Tests
// ============================================================================
 
struct Point
{
  int x, y;
 
  bool operator == (const Point & other) const
  {
    return x == other.x && y == other.y;
  }
};
 
namespace std
{
  template <>
  struct hash<Point>
  {
    size_t operator()(const Point & p) const
    {
      return hash<int>()(p.x) ^ (hash<int>()(p.y) << 1);
    }
  };
}
 
size_t point_hash(const Point & p)
{
  return std::hash<Point>()(p);
}
 
TEST(DynHashTable, CustomType)
{
  DynSetLhash<Point> table(100, point_hash);
 
  Point p1{1, 2};
  Point p2{3, 4};
  Point p3{5, 6};
 
  table.insert(p1);
  table.insert(p2);
  table.insert(p3);
 
  EXPECT_EQ(table.size(), 3u);
  EXPECT_TRUE(table.contains(p1));
  EXPECT_TRUE(table.contains(p2));
  EXPECT_TRUE(table.contains(p3));
 
  Point p4{7, 8};
  EXPECT_FALSE(table.contains(p4));
}
 
int main(int argc, char **argv)
{
  ::testing::InitGoogleTest(&argc, argv);
  return RUN_ALL_TESTS();
}