huffcode_test.cpp

// huffcode_test.cpp
// Glenn G. Chappell
// 29 Nov 2015
//
// For CS 411/611 Fall 2015
// Test program for class HuffCode
// Used in Assignment 6, Exercise A
//
// Modified 11/22/17
// Chris Hartman
// For CS 411 Fall 2017

// Includes for code to be tested
#include "huffcode.hpp"   // For class HuffCode
#include "huffcode.hpp"   // Double inclusion test

// Includes for testing package & code common to all test programs
#include <iostream>     // for std::cout, std::endl, std::cin
#include <string>       // for std::string
#include <stdexcept>    // for std::runtime_error

// Additional includes for this test program
#include <string>       // for std::string
#include <unordered_map>
                        // for std::unordered_map
#include <vector>       // for std::vector
#include <sstream>      // for std::ostringstream


// ************************************************************************
// Testing Package:
//     Class Tester - For Tracking Tests
// ************************************************************************


// class Tester
// For extremely simple unit testing.
// Keeps track of number of tests and number of passes.
// Use test (with success/failure parameter) to do a test.
// Get results with numTests, numPassed, numFailed, allPassed.
// Restart testing with reset.
// Invariants:
//     countTests_ == number of tests (calls to test) since last reset.
//     countPasses_ == number of times function test called with true param
//      since last reset.
//     0 <= countPasses_ <= countTests_.
//     tolerance_ >= 0.
class Tester {

// ***** Tester: ctors, dctor, op= *****
public:

    // Default ctor
    // Sets countTests_, countPasses_ to zero, tolerance_ to given value
    // Pre: None.
    // Post:
    //     numTests == 0, countPasses == 0, tolerance_ == abs(theTolerance)
    // Does not throw (No-Throw Guarantee)
    Tester(double theTolerance = 0.0000001)
        :countTests_(0),
         countPasses_(0),
         tolerance_(theTolerance >= 0 ? theTolerance : -theTolerance)
    {}

    // Compiler-generated copy ctor, copy op=, dctor are used

// ***** Tester: general public functions *****
public:

    // test
    // Handles single test, param indicates pass/fail
    // Pre: None.
    // Post:
    //     countTests_ incremented
    //     countPasses_ incremented if (success)
    //     Message indicating test name (if given)
    //      and pass/fail printed to cout
    // Does not throw (No-Throw Guarantee)
    //  - Assuming exceptions have not been turned on for cout.
    void test(bool success,
              const std::string & testName = "")
    {
        ++countTests_;
        if (success) ++countPasses_;

        std::cout << "    ";
        if (testName != "")
        {
            std::cout << "Test: "
                      << testName
                      << " - ";
        }
        std::cout << (success ? "passed" : "********** FAILED **********")
                  << std::endl;
    }

    // ftest
    // Does single floating-point test.
    // Tests passes iff difference of first two values is <= tolerance.
    // Pre: None.
    // Post:
    //     countTests_ incremented
    //     countPasses_ incremented if (abs(val1-val2) <= tolerance_)
    //     Message indicating test name (if given)
    //      and pass/fail printed to cout
    // Does not throw (No-Throw Guarantee)
    void ftest(double val1,
               double val2,
               const std::string & testName = "")
    { test(val1-val2 <= tolerance_ && val2-val1 <= tolerance_, testName); }

    // reset
    // Resets *this to default constructed state
    // Pre: None.
    // Post:
    //     countTests_ == 0, countPasses_ == 0
    // Does not throw (No-Throw Guarantee)
    void reset()
    {
        countTests_ = 0;
        countPasses_ = 0;
    }

    // numTests
    // Returns the number of tests that have been done since last reset
    // Pre: None.
    // Post:
    //     return == countTests_
    // Does not throw (No-Throw Guarantee)
    int numTests() const
    { return countTests_; }

    // numPassed
    // Returns the number of tests that have passed since last reset
    // Pre: None.
    // Post:
    //     return == countPasses_
    // Does not throw (No-Throw Guarantee)
    int numPassed() const
    { return countPasses_; }

    // numFailed
    // Returns the number of tests that have not passed since last reset
    // Pre: None.
    // Post:
    //     return + countPasses_ == numTests_
    // Does not throw (No-Throw Guarantee)
    int numFailed() const
    { return countTests_ - countPasses_; }

    // allPassed
    // Returns true if all tests since last reset have passed
    // Pre: None.
    // Post:
    //     return == (countPasses_ == countTests_)
    // Does not throw (No-Throw Guarantee)
    bool allPassed() const
    { return countPasses_ == countTests_; }

    // setTolerance
    // Sets tolerance_ to given value
    // Pre: None.
    // Post:
    //     tolerance_ = abs(theTolerance)
    // Does not throw (No-Throw Guarantee)
    void setTolerance(double theTolerance)
    { tolerance_ = (theTolerance >= 0 ? theTolerance : -theTolerance); }

// ***** Tester: data members *****
private:

    int countTests_;    // Number of tests done since last reset
    int countPasses_;   // Number of tests passed since last reset
    double tolerance_;  // Tolerance for floating-point near-equality tests

};  // end class Tester


// ************************************************************************
// Testing Package:
//     Class TypeCheck - Helper Class for Type Checking
// ************************************************************************


// class TypeCheck
// This class exists in order to have static member function check, which
// takes a parameter of a given type, by reference. Objects of type
// TypeCheck<T> cannot be created.
// Usage:
//     TypeCheck<MyType>::check(x)
//     returns true if the type of x is (MyType) or (const MyType),
//     otherwise false.
// Invariants: None.
// Requirements on Types: None.
template<typename T>
class TypeCheck {

private:

    // Uncopyable class. Do not define copy ctor, copy assn.
    TypeCheck(const TypeCheck &);
    TypeCheck<T> & operator=(const TypeCheck &);

    // Compiler-generated dctor is used (but irrelevant).

public:

    // check
    // The function and function template below simulate a single function
    // that takes a single parameter, and returns true iff the parameter has
    // type T or (const T).

    // check (reference-to-const T)
    // Pre: None.
    // Post:
    //     Return is true.
    // Does not throw (No-Throw Guarantee)
    static bool check(const T & param)
    { return true; }

    // check (reference-to-const non-T)
    // Pre: None.
    // Post:
    //     Return is false.
    // Requirements on types: None.
    // Does not throw (No-Throw Guarantee)
    template <typename OtherType>
    static bool check(const OtherType & param)
    { return false; }

};  // End class TypeCheck


// ************************************************************************
// Testing Package:
//     Class Counter - Helper Class for Counting Calls & Objects, Throwing
// ************************************************************************


// class Counter
// Item type for counting ctor, dctor, op= calls, counting existing
//  objects, and possibly throwing on copy. Has operator< (which always
//  returns false), allowing it to be the value type of a sorted container.
// If static member copyThrow_ is set, then copy ctor and copy assn throw
//  std::runtime_error. Exception object's "what" member is set to "C" by
//  the copy ctor and "A" by copy assn.
// Increments static data member ctorCount_ on default construction and
//  successful copy construction. Increments static data member assnCount_
//  on successful copy assignment. Increments static data member
//  dctorCount_ on destruction.
// Increments static data member existing_ on construction, and decrements
//  it on destruction.
// Static data member maxExisting_ is highest value of existing_ since last
//  reset, or start of program if reset has never been called.
// Invariants:
//     Counter::existing_ is number of existing objects of this class.
//     Counter::ctorCount_ is number of successful ctor calls since
//      most recent call to reset, or start of program if reset has never
//      been called.
//     Counter::dctorCount_ is (similarly) number of dctor calls.
//     Counter::assnCount_ is (similarly) number of copy assn calls.
//     Counter::maxExisting_ is (similarly) highest value existing_ has
//      assumed.
class Counter {

// ***** Counter: Ctors, dctor, op= *****
public:

    // Default ctor
    // Pre: None.
    // Post:
    //     (ctorCount_ has been incremented.)
    //     (existing_ has been incremented.)
    // Does not throw (No-Throw Guarantee)
    Counter()
    {
        ++existing_;
        if (existing_ > maxExisting_)
            maxExisting_ = existing_;
        ++ctorCount_;
    }

    // Copy ctor
    // Throws std::runtime_error if copyThrow_.
    // Pre: None.
    // Post:
    //     (ctorCount_ has been incremented.)
    //     (existing_ has been incremented.)
    // May throw std::runtime_error
    // Strong Guarantee
    Counter(const Counter & other)
    {
        if (copyThrow_)
            throw std::runtime_error("C");
        ++existing_;
        if (existing_ > maxExisting_)
            maxExisting_ = existing_;
        ++ctorCount_;
    }

    // Copy assignment
    // Throws std::runtime_error if copyThrow_.
    // Pre: None.
    // Post:
    //     Return value is *this.
    //     (assnCount_ has been incremented.)
    // May throw std::runtime_error
    // Strong Guarantee
    Counter & operator=(const Counter & rhs)
    {
        if (copyThrow_)
            throw std::runtime_error("A");
        ++assnCount_;
        return *this;
    }

    // Dctor
    // Pre: None.
    // Post:
    //     (dctorCount_ has been incremented.)
    //     (existing_ has been decremented.)
    // Does not throw (No-Throw Guarantee)
    ~Counter()
    {
        --existing_;
        ++dctorCount_;
    }

// ***** Counter: Functions dealing with count *****
public:

    // reset
    // Pre: None.
    // Post:
    //     maxExisting_ == existing_.
    //     ctorCount_ == 0.
    //     dctorCount_ == 0.
    //     assnCount_ == 0.
    //     copyThrow_ == shouldThrow.
    // Does not throw (No-Throw Guarantee)
    static void reset(bool shouldThrow = false)
    {
        maxExisting_ = existing_;
        ctorCount_ = 0;
        dctorCount_ = 0;
        assnCount_ = 0;
        copyThrow_ = shouldThrow;
    }

    // getExisting
    // Pre: None.
    // Post:
    //     return == existing_.
    // Does not throw (No-Throw Guarantee)
    static int getExisting()
    { return existing_; }

    // getMaxExisting
    // Pre: None.
    // Post:
    //     return == maxExisting_.
    // Does not throw (No-Throw Guarantee)
    static int getMaxExisting()
    { return maxExisting_; }

    // getCtorCount
    // Pre: None.
    // Post:
    //     return == ctorCount_.
    // Does not throw (No-Throw Guarantee)
    static int getCtorCount()
    { return ctorCount_; }

    // getDctorCount
    // Pre: None.
    // Post:
    //     return == dctorCount_.
    // Does not throw (No-Throw Guarantee)
    static int getDctorCount()
    { return dctorCount_; }

    // getAssnCount
    // Pre: None.
    // Post:
    //     return == assnCount_.
    // Does not throw (No-Throw Guarantee)
    static int getAssnCount()
    { return assnCount_; }

    // setCopyThrow
    // Pre: None.
    // Post:
    //     copyThrow_ == shouldThrow
    // Does not throw (No-Throw Guarantee)
    static void setCopyThrow(bool shouldThrow)
    { copyThrow_ = shouldThrow; }

// ***** Counter: Data Members *****
private:

    static int existing_;     // # of existing objects
    static int maxExisting_;  // Max # of existing objects
    static int ctorCount_;    // # of successful (non-throwing) ctor calls
    static int dctorCount_;   // # of dctor calls
    static int assnCount_;    // # of successful (non-throwing) copy = calls
    static bool copyThrow_;   // true if copy operations (ctor, =) throw

};  // End class Counter

// Definition of static data member of class Counter
int Counter::existing_ = 0;
int Counter::maxExisting_ = 0;
int Counter::ctorCount_ = 0;
int Counter::dctorCount_ = 0;
int Counter::assnCount_ = 0;
bool Counter::copyThrow_ = false;


// operator< (Counter)
// Dummy-ish operator<, forming a strict weak order for Counter class
// Returns false (which is legal for a strict weak order; all objects of
//  type Counter are equivalent).
// Pre: None.
// Post:
//     Return value == false.
// Does not throw (No-Throw Guarantee)
bool operator<(const Counter & a,
               const Counter & b)
{ return false; }


// ************************************************************************
// Helper Functions/Classes/Types for This Test Program
// ************************************************************************


// matchPattern
// Pattern matching for Huffman-coded strings
bool matchPattern(const std::string & pattern,
                  const std::string & coded)
{
    size_t len = pattern.size();
    if (len != coded.size())
        return false;

    std::unordered_map<char, char> m;
    for (size_t i = 0; i != len; ++i)
    {
        char tc = coded[i];
        if (tc != '0' && tc != '1')
            return false;

        char pc = pattern[i];
        bool islower =  (pc >= 'a');
        char pcupper = islower ? char(pc - 'a' + 'A') : pc;

        char tcbase = islower ? char('1'-(tc-'0')) : tc;

        if (m.find(pcupper) != m.end())
        {
            if (tcbase != m[pcupper])
                return false;
        }
        else
        {
            m[pcupper] = tcbase;
        }
    }
    return true;
}


// ************************************************************************
// Test Suite Functions
// ************************************************************************


// test_HuffCode_types
// Test suite for class HuffCode: types
// Pre: None.
// Post:
//     Pass/fail status of tests have been registered with t.
//     Appropriate messages have been printed to cout.
// Does not throw (No-Throw Guarantee)
void test_HuffCode_types(Tester & t)
{
    std::cout << "Test Suite: class HuffCode - type checking"
              << std::endl;

    HuffCode h;
    const std::unordered_map<char, int> cw;
    h.setWeights(cw);
    const HuffCode & ch(h);

    // Return type of encode
    const std::string s = "";
    t.test(TypeCheck<std::string>::check(ch.encode(s)),
        "Return type of encode is string");

    // Return type of decode
    t.test(TypeCheck<std::string>::check(ch.decode("")),
        "Return type of decode is string");
}


// test_HuffCode_simple
// Test suite for class HuffCode: simple code
// Pre: None.
// Post:
//     Pass/fail status of tests have been registered with t.
//     Appropriate messages have been printed to cout.
// Does not throw (No-Throw Guarantee)
void test_HuffCode_simple(Tester & t)
{
    std::cout << "Test Suite: class HuffCode - simple code"
              << std::endl;

    HuffCode h;
    std::unordered_map<char, int> w;
    w['a'] = 3;
    w['b'] = 2;
    w['c'] = 1;
    const std::unordered_map<char, int> & cw(w);
    h.setWeights(cw);

    std::string text, retval, pat, correct;
    bool result;

    // Encode empty text
    text = "";
    retval = h.encode(text);
    correct = "";
    result = (retval == correct);
    t.test(result, "encode empty text");
    if (!result)
    {
        std::cout << "        "
                  << "Expecting: \"" << correct << "\"" << std::endl;
        std::cout << "        "
                  << "Received:  \"" << retval << "\"" << std::endl;
    }

    // Encode all characters
    text = "abc";
    retval = h.encode(text);
    pat = "aAbAB";
    result = matchPattern(pat, retval);
    t.test(result, "encode all characters");
    if (!result)
    {
        std::cout << "        "
                  << "Expecting: \"01011\" or \"01110\" or \"10001\" or \"10100\""
                  << std::endl;
        std::cout << "        "
                  << "Received:  \"" << retval << "\"" << std::endl;
        std::cout << "    "
                  << "EXITING TEST SUITE" << std::endl;
        return;
    }

    std::vector<std::string> cwd;
    cwd.push_back(retval.substr(0, 1));
    cwd.push_back(retval.substr(1, 2));
    cwd.push_back(retval.substr(3, 2));

    // Encode single characters
    for (size_t i = 0; i != cwd.size(); ++i)
    {
        text = std::string(1, 'a'+char(i));
        retval = h.encode(text);
        correct = cwd[i];
        result = (retval == correct);
        std::ostringstream os1;
        os1 << i+1;
        t.test(result, "encode single-character text #" + os1.str());
        if (!result)
        {
            std::cout << "        "
                      << "Expecting: \"" << correct << "\"" << std::endl;
            std::cout << "        "
                      << "Received:  \"" << retval << "\"" << std::endl;
        }
    }

    // Encode longer text
    text = "aaabacbabbbccacbcc";
    retval = h.encode(text);
    correct = cwd[0]+cwd[0]+cwd[0]+cwd[1]+cwd[0]+cwd[2]
             +cwd[1]+cwd[0]+cwd[1]+cwd[1]+cwd[1]+cwd[2]
             +cwd[2]+cwd[0]+cwd[2]+cwd[1]+cwd[2]+cwd[2];
    result = (retval == correct);
    t.test(result, "encode longer text");
    if (!result)
    {
        std::cout << "        "
                  << "Expecting: \"" << correct << "\"" << std::endl;
        std::cout << "        "
                  << "Received:  \"" << retval << "\"" << std::endl;
    }

    // Decode empty text
    text = "";
    retval = h.decode(text);
    correct = "";
    result = (retval == correct);
    t.test(result, "decode empty text");
    if (!result)
    {
        std::cout << "        "
                  << "Expecting: \"" << correct << "\"" << std::endl;
        std::cout << "        "
                  << "Received:  \"" << retval << "\"" << std::endl;
    }

    // Decode single characters
    for (size_t i = 0; i != cwd.size(); ++i)
    {
        text = cwd[i];
        retval = h.decode(text);
        correct = std::string(1, 'a'+char(i));
        result = (retval == correct);
        std::ostringstream os1;
        os1 << i+1;
        t.test(result, "decode single-character text #" + os1.str());
        if (!result)
        {
            std::cout << "        "
                      << "Expecting: \"" << correct << "\"" << std::endl;
            std::cout << "        "
                      << "Received:  \"" << retval << "\"" << std::endl;
        }
    }

    // Decode longer text
    text = cwd[0]+cwd[1]+cwd[2]+cwd[0]+cwd[2]+cwd[1]
          +cwd[1]+cwd[0]+cwd[2]+cwd[1]+cwd[2]+cwd[0]
          +cwd[2]+cwd[0]+cwd[1]+cwd[2]+cwd[1]+cwd[0]
          +cwd[0]+cwd[0]+cwd[0]+cwd[1]+cwd[1]+cwd[1]
          +cwd[2]+cwd[2]+cwd[2];
    retval = h.decode(text);
    correct = "abcacbbacbcacabcbaaaabbbccc";
    result = (retval == correct);
    t.test(result, "decode longer text");
    if (!result)
    {
        std::cout << "        "
                  << "Expecting: \"" << correct << "\"" << std::endl;
        std::cout << "        "
                  << "Received:  \"" << retval << "\"" << std::endl;
    }
}


// test_HuffCode_complex
// Test suite for class HuffCode: complex code
// Pre: None.
// Post:
//     Pass/fail status of tests have been registered with t.
//     Appropriate messages have been printed to cout.
// Does not throw (No-Throw Guarantee)
void test_HuffCode_complex(Tester & t)
{
    std::cout << "Test Suite: class HuffCode - complex code"
              << std::endl;

    HuffCode h;
    std::unordered_map<char, int> w;
    w['a'] = 2;
    w['b'] = 20;
    w['c'] = 3;
    w['d'] = 8;
    w['e'] = 12;
    w['f'] = 3;
    w['g'] = 8;
    w['h'] = 2;
    w['i'] = 7;
    w['j'] = 5;
    h.setWeights(w);

    std::string text, retval, pat, correct;
    bool result;

    // Encode empty text
    text = "";
    retval = h.encode(text);
    correct = "";
    result = (retval == correct);
    t.test(result, "encode empty text");

    // Encode all characters
    text = "abcdefghij";
    retval = h.encode(text);
    pat = "ihFcAiHIGDbIgEihfIGDBIgeihFcaIGdihFC";
    result = matchPattern(pat, retval);
    t.test(result, "encode all characters");
    if (!result)
    {
        std::cout << "    "
                  << "EXITING TEST SUITE" << std::endl;
        return;
    }

    std::vector<std::string> cwd;
    cwd.push_back(retval.substr(0, 5));
    cwd.push_back(retval.substr(5, 2));
    cwd.push_back(retval.substr(7, 4));
    cwd.push_back(retval.substr(11, 3));
    cwd.push_back(retval.substr(14, 3));
    cwd.push_back(retval.substr(17, 4));
    cwd.push_back(retval.substr(21, 3));
    cwd.push_back(retval.substr(24, 5));
    cwd.push_back(retval.substr(29, 3));
    cwd.push_back(retval.substr(32, 4));

    // Encode single characters
    for (size_t i = 0; i != cwd.size(); ++i)
    {
        text = std::string(1, 'a'+char(i));
        retval = h.encode(text);
        correct = cwd[i];
        result = (retval == correct);
        std::ostringstream os1;
        os1 << i+1;
        t.test(result, "encode single-character text #" + os1.str());
    }

    // Encode longer text
    text = "ajabcffhcdihgjihgfedcba";
    retval = h.encode(text);
    correct = cwd[0]+cwd[9]+cwd[0]+cwd[1]+cwd[2]+cwd[5]+cwd[5]+cwd[7]
             +cwd[2]+cwd[3]+cwd[8]+cwd[7]+cwd[6]+cwd[9]+cwd[8]+cwd[7]
             +cwd[6]+cwd[5]+cwd[4]+cwd[3]+cwd[2]+cwd[1]+cwd[0];
    result = (retval == correct);
    t.test(result, "encode longer text");

    // Decode empty text
    text = "";
    retval = h.decode(text);
    correct = "";
    result = (retval == correct);
    t.test(result, "decode empty text");

    // Decode single characters
    for (size_t i = 0; i != cwd.size(); ++i)
    {
        text = cwd[i];
        retval = h.decode(text);
        correct = std::string(1, 'a'+char(i));
        result = (retval == correct);
        std::ostringstream os1;
        os1 << i+1;
        t.test(result, "decode single-character text #" + os1.str());
        if (!result)
        {
            std::cout << "        "
                      << "Expecting: \"" << correct << "\"" << std::endl;
            std::cout << "        "
                      << "Received:  \"" << retval << "\"" << std::endl;
        }
    }

    // Decode longer text
    text = cwd[6]+cwd[9]+cwd[0]+cwd[8]+cwd[9]+cwd[9]+cwd[3]+cwd[3]+cwd[3]
          +cwd[4]+cwd[8]+cwd[9]+cwd[2]+cwd[6]+cwd[1]+cwd[7]+cwd[4]+cwd[0]
          +cwd[5]+cwd[1]+cwd[5]+cwd[0]+cwd[2]+cwd[8]+cwd[8]+cwd[8];
    retval = h.decode(text);
    correct = "gjaijjdddeijcgbheafbfaciii";
    result = (retval == correct);
    t.test(result, "decode longer text");
}


// test_HuffCode_copy
// Test suite for class HuffCode: copying
// Pre: None.
// Post:
//     Pass/fail status of tests have been registered with t.
//     Appropriate messages have been printed to cout.
// Does not throw (No-Throw Guarantee)
void test_HuffCode_copy(Tester & t)
{
    std::cout << "Test Suite: class HuffCode - copying HuffCode object"
              << std::endl;

    HuffCode h;
    std::unordered_map<char, int> w;
    w['a'] = 3;
    w['b'] = 2;
    w['c'] = 1;
    h.setWeights(w);
    const HuffCode ch(h);

    std::string text, retval, pat, correct;
    bool result;

    // Encode all characters
    text = "abc";
    retval = ch.encode(text);
    pat = "aAbAB";
    result = matchPattern(pat, retval);
    t.test(result, "copy, encode all characters");
    if (!result)
    {
        std::cout << "        "
                  << "Expecting: \"01011\" or \"01110\" or \"10001\" or \"10100\""
                  << std::endl;
        std::cout << "        "
                  << "Received:  \"" << retval << "\"" << std::endl;
        std::cout << "    "
                  << "EXITING TEST SUITE" << std::endl;
        return;
    }

    std::vector<std::string> cwd;
    cwd.push_back(retval.substr(0, 1));
    cwd.push_back(retval.substr(1, 2));
    cwd.push_back(retval.substr(3, 2));

    // Encode text
    text = "aaabacbabbbccacbcc";
    retval = ch.encode(text);
    correct = cwd[0]+cwd[0]+cwd[0]+cwd[1]+cwd[0]+cwd[2]
             +cwd[1]+cwd[0]+cwd[1]+cwd[1]+cwd[1]+cwd[2]
             +cwd[2]+cwd[0]+cwd[2]+cwd[1]+cwd[2]+cwd[2];
    result = (retval == correct);
    t.test(result, "copy, encode text");
    if (!result)
    {
        std::cout << "        "
                  << "Expecting: \"" << correct << "\"" << std::endl;
        std::cout << "        "
                  << "Received:  \"" << retval << "\"" << std::endl;
    }

    // Decode text
    text = cwd[0]+cwd[1]+cwd[2]+cwd[0]+cwd[2]+cwd[1]
          +cwd[1]+cwd[0]+cwd[2]+cwd[1]+cwd[2]+cwd[0]
          +cwd[2]+cwd[0]+cwd[1]+cwd[2]+cwd[1]+cwd[0]
          +cwd[0]+cwd[0]+cwd[0]+cwd[1]+cwd[1]+cwd[1]
          +cwd[2]+cwd[2]+cwd[2];
    retval = ch.decode(text);
    correct = "abcacbbacbcacabcbaaaabbbccc";
    result = (retval == correct);
    t.test(result, "copy, decode text");
    if (!result)
    {
        std::cout << "        "
                  << "Expecting: \"" << correct << "\"" << std::endl;
        std::cout << "        "
                  << "Received:  \"" << retval << "\"" << std::endl;
    }
}


// test_class_HuffCode
// Test suite for class HuffCode
// Uses other test-suite functions
// Pre: None.
// Post:
//     Pass/fail status of tests have been registered with t.
//     Appropriate messages have been printed to cout.
// Does not throw (No-Throw Guarantee)
void test_class_HuffCode(Tester & t)
{
    // Do all the test suites
    std::cout << "TEST SUITES FOR CLASS HuffCode" << std::endl;
    test_HuffCode_types(t);
    test_HuffCode_simple(t);
    test_HuffCode_complex(t);
    test_HuffCode_copy(t);
}


// ************************************************************************
// Main program
// ************************************************************************


// main
// Runs class HuffCode test suite, prints results to cout.
int main()
{
    Tester t;
    test_class_HuffCode(t);

    std::cout << std::endl;
    if (t.allPassed())
    {
        std::cout << "All tests successful"
                  << std::endl;
    }
    else
    {
        std::cout << "Tests ********** UNSUCCESSFUL **********"
                  << std::endl;
    }
    std::cout << std::endl;

    // Wait for user
    std::cout << "Press ENTER to quit ";
    while (std::cin.get() != '\n') ;

    return 0;
}