hash_test.cpp

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//Has to be first for StackAllocator swap overload to be taken
//into account (at least using GCC 4.0.1)
#include "stack_allocator.h"

#include <vector>
#include <algorithm>
#include <map>
#include <set>

#if defined (STLPORT) && !defined (_STLP_NO_EXTENSIONS)
#  include <hash_map>
#  include <hash_set>
#  include <rope>
#endif

#include <string>

#include "cppunit/cppunit_proxy.h"

#if defined (__MVS__)
const char star = 92;
#else
const char star = 42;
#endif

#if !defined (STLPORT) || defined (_STLP_USE_NAMESPACES)
using namespace std;
#endif

//
// TestCase class
//
class HashTest : public CPPUNIT_NS::TestCase
{
  CPPUNIT_TEST_SUITE(HashTest);
#if !defined (STLPORT) || defined (_STLP_NO_EXTENSIONS)
  CPPUNIT_IGNORE;
#endif
  CPPUNIT_TEST(hmap1);
  CPPUNIT_TEST(hmmap1);
  CPPUNIT_TEST(hmmap2);
  CPPUNIT_TEST(hmset1);
  CPPUNIT_TEST(hset2);
  CPPUNIT_TEST(insert_erase);
  CPPUNIT_TEST(allocator_with_state);
  //CPPUNIT_TEST(equality);
  CPPUNIT_TEST_SUITE_END();

#if defined (STLPORT) && !defined (_STLP_NO_EXTENSIONS)
  typedef hash_multiset<char, hash<char>, equal_to<char> > hmset;
#endif

protected:
  void hmap1();
  void hmmap1();
  void hmmap2();
  void hmset1();
  void hset2();
  void insert_erase();
  //void equality();
  void allocator_with_state();

#if defined (STLPORT) && !defined (_STLP_NO_EXTENSIONS)
  typedef hash_multimap<int, int> hashType;
  typedef multimap<int, int> mapType;

  void check_keys( hashType& h, mapType& m );
#endif
};

CPPUNIT_TEST_SUITE_REGISTRATION(HashTest);

//
// tests implementation
//
void HashTest::hmap1()
{
#if defined (STLPORT) && !defined (_STLP_NO_EXTENSIONS)
  typedef hash_map<char, crope, hash<char>, equal_to<char> > maptype;
  maptype m;
  // Store mappings between roman numerals and decimals.
  m['l'] = "50";
  m['x'] = "20"; // Deliberate mistake.
  m['v'] = "5";
  m['i'] = "1";
  CPPUNIT_ASSERT( !strcmp(m['x'].c_str(),"20") );
  m['x'] = "10"; // Correct mistake.
  CPPUNIT_ASSERT( !strcmp(m['x'].c_str(),"10") );

  CPPUNIT_ASSERT( !strcmp(m['z'].c_str(),"") );

  CPPUNIT_ASSERT( m.count('z')==1 );
  pair<maptype::iterator, bool> p = m.insert(pair<const char, crope>('c', crope("100")));

  CPPUNIT_ASSERT(p.second);

  p = m.insert(pair<const char, crope>('c', crope("100")));
  CPPUNIT_ASSERT(!p.second);

  //Some iterators compare check, really compile time checks
  maptype::iterator ite(m.begin());
  maptype::const_iterator cite(m.begin());
  cite = m.begin();
  maptype const& cm = m;
  cite = cm.begin();
  CPPUNIT_ASSERT( ite == cite );
  CPPUNIT_ASSERT( !(ite != cite) );
  CPPUNIT_ASSERT( cite == ite );
  CPPUNIT_ASSERT( !(cite != ite) );
#endif
}

void HashTest::hmmap1()
{
#if defined (STLPORT) && !defined (_STLP_NO_EXTENSIONS)
  typedef hash_multimap<char, int, hash<char>,equal_to<char> > mmap;
  mmap m;
  CPPUNIT_ASSERT(m.count('X')==0);
  m.insert(pair<const char,int>('X', 10)); // Standard way.
  CPPUNIT_ASSERT(m.count('X')==1);
//  m.insert('X', 20); // Non-standard, but very convenient!
  m.insert(pair<const char,int>('X', 20));  // jbuck: standard way
  CPPUNIT_ASSERT(m.count('X')==2);
//  m.insert('Y', 32);
  m.insert(pair<const char,int>('Y', 32));  // jbuck: standard way
  mmap::iterator i = m.find('X'); // Find first match.

  CPPUNIT_ASSERT((*i).first=='X');
  CPPUNIT_ASSERT((*i).second==10);
  i++;
  CPPUNIT_ASSERT((*i).first=='X');
  CPPUNIT_ASSERT((*i).second==20);
  i++;
  CPPUNIT_ASSERT((*i).first=='Y');
  CPPUNIT_ASSERT((*i).second==32);
  i++;
  CPPUNIT_ASSERT(i==m.end());

  size_t count = m.erase('X');
  CPPUNIT_ASSERT(count==2);

  //Some iterators compare check, really compile time checks
  mmap::iterator ite(m.begin());
  mmap::const_iterator cite(m.begin());
  CPPUNIT_ASSERT( ite == cite );
  CPPUNIT_ASSERT( !(ite != cite) );
  CPPUNIT_ASSERT( cite == ite );
  CPPUNIT_ASSERT( !(cite != ite) );

  typedef hash_multimap<size_t, size_t> HMapType;
  HMapType hmap;

  //We fill the map to implicitely start a rehash.
  for (size_t counter = 0; counter < 3077; ++counter)
    hmap.insert(HMapType::value_type(1, counter));

  hmap.insert(HMapType::value_type(12325, 1));
  hmap.insert(HMapType::value_type(12325, 2));

  CPPUNIT_ASSERT( hmap.count(12325) == 2 );

  //At this point 23 goes to the same bucket as 12325, it used to reveal a bug.
  hmap.insert(HMapType::value_type(23, 0));

  CPPUNIT_ASSERT( hmap.count(12325) == 2 );
#endif
}

#if defined (STLPORT) && !defined (_STLP_NO_EXTENSIONS)
// Short demonstrator that helps reproducing a bug in the hash-table implementation
// of STLPort 5.0.1/5.0.2.
//
// Problem: Fill a hash_multimap with entries of which many have the same key
//          Internally, entries with the same key are kept as one block within the same bucket.
//          Thus, when calling equal_range(key) the begin/end of that block is returned.
//          However, this code shows that for key =3, that block is destroyed after inserting the 194th element.
//          According to _hashtable.c we will have a rehash from size 193 to size 389 in that situation.
//          After that rehash,  equal_range only returns 2 elements with key = 3 whereas there are 65 in it.
// Reproduction:
//          In the main()-method we fill a hash_multimap as well as a multi_map with the same <key, data> pairs
//          After each insertion we call check_keys(...) to assure validity of these two containers.
//          This works fine up to the 193th insertion. Insertion 194 generates the bug.
//
//          check_keys() works as follows:
//          (a) we check whether both containers contain the same number of elements.
//          (b) Assuming that the multi_map works correctly, we iterate over all its elements and check
//              whether we can find that key also in the hash_multimap. We collect all data for that specific
//              key in in a set ("collection"). Notice that data is unique by construction in main(), thus the
//              number of elements in the set must equal the number of entries in the hash_multimap and in the multimap
//          (c) We check if we have seen as many data elements in collection as we have seen in the multimap.
//              if so, we print "OK", otherwise we print a detailed key/data overview and assert.
// Caution:
//        There are several configurations of the program that will NOT fail. (see comment in code below)
//        E.g. it seems that whenever the keys are more or less sorted, the problem does not occur.
//        Also, using numbers from 200 downto 1 or from 300 downto 1 cannot generate the problem,
//        whereas using 400 downto 1 will fail.
//        Finally, if we use key 1 (rather than key 3) we cannot generate a problem.

void HashTest::check_keys( HashTest::hashType& h, HashTest::mapType& m )
{
  set<int> collection;

  // (a) check sizes
  CPPUNIT_CHECK( h.size() == m.size() );

  // (b) iterate over multi_map
  for ( mapType::iterator i = m.begin(); i != m.end(); ++i ) {
    // look up that key in hash-table and keep all data in the set
    pair<hashType::iterator,hashType::iterator> range = h.equal_range( i->first );
    for ( hashType::iterator j = range.first; j != range.second; ++j ) {
      collection.insert( j->second );
    }
  }
  // (c) we should have seen as many elements as there are in the hash-table
#if 0
  if (collection.size() == h.size()) cout << " OK" << endl;
  else {
    // if not, please report
    cout << " FAILED: " << endl;
    int lastKey  = -1;
    // iterate over all elements in multi_map
    for (mapType::iterator mIter = m.begin(); mIter != m.end(); mIter++) {
      // new key? print a new status line
      if (mIter->first != lastKey) {
        cout << endl << "Key : " << mIter->first << endl;
        lastKey = mIter->first;

        // print all hashed values for that key
        cout << " data in hash: ";
        pair<hashType::iterator,hashType::iterator> range = h.equal_range(mIter->first);

        for (hashType::iterator h = range.first; h != range.second; h++) {
          assert (h->first == lastKey);
          cerr << h->second << ", "; // print all data for that key in Hash-Table
        }
        cout << endl << " data in map:  ";
      }
      // and print all member in multi-map until the next key occurs
      cout << mIter->second << ", " ;  // print all data for that key in Map
    }
  }
#endif
  CPPUNIT_CHECK( collection.size() == h.size() );
}

#endif

void HashTest::hmmap2()
{
#if defined (STLPORT) && !defined (_STLP_NO_EXTENSIONS)
  hashType h;
  mapType m;

  // CAUTION the following configurations WORKS in our setting
  //      for (int id = 1; id != 400; id ++)   and int key = (id %3 == 0 ? 3 : id)
  //      for (int id = 200; id != 1; id --)   and int key = (id %3 == 0 ? 3 : id)
  //      for (int id = 300; id != 1; id --)   and int key = (id %3 == 0 ? 3 : id)
  //      for (int id = 400; id != 1; id --)   and int key = (id %3 == 0 ? 1 : id)
  //      for (int id = 4000; id != 1; id --)  and int key = (id %3 == 0 ? 1 : id)
  //
  // whereas these will FAIL
  //      for (int id = 400; id != 1; id --)   and int key = (id %3 == 0 ? 3 : id)
  //      for (int id = 4000; id != 1; id --)  and int key = (id %3 == 0 ? 3 : id)
  //

  for ( int id = 400; id != 1; id-- ) {
    // generate many entries with key 3, fill up with unique keys. Data is unique (needed in check_keys())
    int key = (id % 3 == 0 ? 3 : id);

    // keep hash_multi_map and multimap in sync
    h.insert(make_pair(key, id));
    m.insert(make_pair(key, id));

    // check whether both contain the same elements
    check_keys( h, m );
  }
#endif
}

void HashTest::hmset1()
{
#if defined (STLPORT) && !defined (_STLP_NO_EXTENSIONS)
  hmset s;
  CPPUNIT_ASSERT( s.count(star) == 0 );
  s.insert(star);
  CPPUNIT_ASSERT( s.count(star) == 1 );
  s.insert(star);
  CPPUNIT_ASSERT( s.count(star) == 2 );
  hmset::iterator i = s.find(char(40));
  CPPUNIT_ASSERT( i == s.end() );

  i = s.find(star);
  CPPUNIT_ASSERT( i != s.end() )
  CPPUNIT_ASSERT( *i == '*' );
  CPPUNIT_ASSERT( s.erase(star) == 2 );
#endif
}
void HashTest::hset2()
{
#if defined (STLPORT) && !defined (_STLP_NO_EXTENSIONS)
  hash_set<int, hash<int>, equal_to<int> > s;
  pair<hash_set<int, hash<int>, equal_to<int> >::iterator, bool> p = s.insert(42);
  CPPUNIT_ASSERT( p.second );
  CPPUNIT_ASSERT( *(p.first) == 42 );

  p = s.insert(42);
  CPPUNIT_ASSERT( !p.second );
#endif
}

void HashTest::insert_erase()
{
#if defined (STLPORT) && !defined (_STLP_NO_EXTENSIONS)
  typedef hash_map<string, size_t, hash<string>, equal_to<string> > hmap;
  typedef hmap::value_type val_type;
  {
    hmap values;
#  if !defined (__BORLANDC__) || (__BORLANDC__ >= 0x564)
    CPPUNIT_ASSERT( values.insert(val_type("foo", 0)).second );
    CPPUNIT_ASSERT( values.insert(val_type("bar", 0)).second );
    CPPUNIT_ASSERT( values.insert(val_type("abc", 0)).second );
#  else
    CPPUNIT_ASSERT( values.insert(hmap::value_type("foo", 0)).second );
    CPPUNIT_ASSERT( values.insert(hmap::value_type("bar", 0)).second );
    CPPUNIT_ASSERT( values.insert(hmap::value_type("abc", 0)).second );
#  endif

    CPPUNIT_ASSERT( values.erase("foo") == 1 );
    CPPUNIT_ASSERT( values.erase("bar") == 1 );
    CPPUNIT_ASSERT( values.erase("abc") == 1 );
  }

  {
    hmap values;
#  if !defined (__BORLANDC__) || (__BORLANDC__ >= 0x564)
    CPPUNIT_ASSERT( values.insert(val_type("foo", 0)).second );
    CPPUNIT_ASSERT( values.insert(val_type("bar", 0)).second );
    CPPUNIT_ASSERT( values.insert(val_type("abc", 0)).second );
#  else
    CPPUNIT_ASSERT( values.insert(hmap::value_type("foo", 0)).second );
    CPPUNIT_ASSERT( values.insert(hmap::value_type("bar", 0)).second );
    CPPUNIT_ASSERT( values.insert(hmap::value_type("abc", 0)).second );
#  endif

    CPPUNIT_ASSERT( values.erase("abc") == 1 );
    CPPUNIT_ASSERT( values.erase("bar") == 1 );
    CPPUNIT_ASSERT( values.erase("foo") == 1 );
  }
#endif
}

/*
 * Here is the test showing why equality operator on hash containers
 * has no meaning:

struct equality_hash_func {
  size_t operator () (size_t val) const {
    return val % 10;
  }
};

void HashTest::equality()
{
  hash_set<size_t, equality_hash_func, equal_to<size_t> > s1, s2;

  s1.insert(10);
  s1.insert(20);

  s2.insert(20);
  s2.insert(10);

  //s1 and s2 contains both 10 and 20:
  CPPUNIT_ASSERT( s1 == s2 );
}
*/

void HashTest::allocator_with_state()
{
#if defined (STLPORT) && !defined (_STLP_NO_EXTENSIONS)
  char buf1[2048];
  StackAllocator<int> stack1(buf1, buf1 + sizeof(buf1));

  char buf2[2048];
  StackAllocator<int> stack2(buf2, buf2 + sizeof(buf2));

  {
    typedef hash_set<int, hash<int>, equal_to<int>, StackAllocator<int> > HashSetInt;
    HashSetInt hint1(10, hash<int>(), equal_to<int>(), stack1);

    int i;
    for (i = 0; i < 5; ++i)
      hint1.insert(i);
    HashSetInt hint1Cpy(hint1);

    HashSetInt hint2(10, hash<int>(), equal_to<int>(), stack2);
    for (; i < 10; ++i)
      hint2.insert(i);
    HashSetInt hint2Cpy(hint2);

    hint1.swap(hint2);

    CPPUNIT_ASSERT( hint1.get_allocator().swaped() );
    CPPUNIT_ASSERT( hint2.get_allocator().swaped() );

    CPPUNIT_ASSERT( hint1.get_allocator() == stack2 );
    CPPUNIT_ASSERT( hint2.get_allocator() == stack1 );
  }
  CPPUNIT_ASSERT( stack1.ok() );
  CPPUNIT_ASSERT( stack2.ok() );
#endif
}

#if defined (STLPORT) && !defined (_STLP_NO_EXTENSIONS) && \
   (!defined (_STLP_USE_PTR_SPECIALIZATIONS) || defined (_STLP_CLASS_PARTIAL_SPECIALIZATION))
#  if !defined (__DMC__)

/* Simple compilation test: Check that nested types like iterator
 * can be access even if type used to instanciate container is not
 * yet completely defined.
 */
class IncompleteClass
{
  hash_set<IncompleteClass> hsinstances;
  typedef hash_set<IncompleteClass>::iterator hsit;
  hash_multiset<IncompleteClass> hsminstances;
  typedef hash_multiset<IncompleteClass>::iterator hsmit;

  hash_map<IncompleteClass, IncompleteClass> hminstances;
  typedef hash_map<IncompleteClass, IncompleteClass>::iterator hmit;
  hash_multimap<IncompleteClass, IncompleteClass> hmminstances;
  typedef hash_multimap<IncompleteClass, IncompleteClass>::iterator hmmit;
};
#  endif
#endif