juce_Enumerate_test.cpp

/*
  ==============================================================================
 
   This file is part of the JUCE library.
   Copyright (c) 2022 - Raw Material Software Limited
 
   JUCE is an open source library subject to commercial or open-source
   licensing.
 
   The code included in this file is provided under the terms of the ISC license
   http://www.isc.org/downloads/software-support-policy/isc-license. Permission
   To use, copy, modify, and/or distribute this software for any purpose with or
   without fee is hereby granted provided that the above copyright notice and
   this permission notice appear in all copies.
 
   JUCE IS PROVIDED "AS IS" WITHOUT ANY WARRANTY, AND ALL WARRANTIES, WHETHER
   EXPRESSED OR IMPLIED, INCLUDING MERCHANTABILITY AND FITNESS FOR PURPOSE, ARE
   DISCLAIMED.
 
  ==============================================================================
*/
 
namespace juce
{
 
class EnumerateUnitTest : public UnitTest
{
public:
    EnumerateUnitTest() : UnitTest ("Enumerate", UnitTestCategories::containers) {}
 
    void runTest() override
    {
        beginTest ("enumeration works for bidirectional iterators");
        {
            const std::list<int> elements { 10, 20, 30, 40, 50 };
            std::vector<int> counts;
 
            for (const auto pair : enumerate (elements))
                counts.push_back ((int) pair.index);
 
            expect (counts == std::vector<int> { 0, 1, 2, 3, 4 });
        }
 
        beginTest ("enumeration works for random-access iterators");
        {
            const std::vector<std::string> strings { "a", "bb", "ccc", "dddd", "eeeee" };
 
            std::vector<int> counts;
 
            for (const auto [count, element] : enumerate (strings))
                counts.push_back ((int) ((size_t) count + element.size()));
 
            expect (counts == std::vector<int> { 1, 3, 5, 7, 9 });
        }
 
        beginTest ("enumeration works for mutable ranges");
        {
            std::vector<std::string> strings { "", "", "", "", "" };
 
            for (const auto [count, element] : enumerate (strings))
                element = std::to_string (count);
 
            expect (strings == std::vector<std::string> { "0", "1", "2", "3", "4" });
        }
 
        beginTest ("iterator can be incremented by more than one");
        {
            std::vector<int> ints (6);
 
            const auto enumerated = enumerate (ints);
 
            std::vector<int> counts;
 
            for (auto b = enumerated.begin(), e = enumerated.end(); b != e; b += 2)
                counts.push_back ((int) (*b).index);
 
            expect (counts == std::vector<int> { 0, 2, 4 });
        }
 
        beginTest ("iterator can be started at a non-zero value");
        {
            const std::vector<int> ints (6);
 
            std::vector<int> counts;
 
            for (const auto enumerated : enumerate (ints, 5))
                counts.push_back ((int) enumerated.index);
 
            expect (counts == std::vector<int> { 5, 6, 7, 8, 9, 10 });
        }
 
        beginTest ("subtracting two EnumerateIterators returns the difference between the base iterators");
        {
            const std::vector<int> ints (6);
            const auto enumerated = enumerate (ints);
            expect ((int) (enumerated.end() - enumerated.begin()) == (int) ints.size());
        }
 
        beginTest ("EnumerateIterator can be decremented");
        {
            const std::vector<int> ints (5);
            std::vector<int> counts;
 
            const auto enumerated = enumerate (std::as_const (ints));
 
            for (auto i = enumerated.end(), b = enumerated.begin(); i != b; --i)
                counts.push_back ((int) (*(i - 1)).index);
 
            expect (counts == std::vector<int> { -1, -2, -3, -4, -5 });
        }
 
        beginTest ("EnumerateIterator can be compared");
        {
            const std::vector<int> ints (6);
            const auto enumerated = enumerate (ints);
            expect (enumerated.begin() < enumerated.end());
            expect (enumerated.begin() <= enumerated.end());
            expect (enumerated.end() > enumerated.begin());
            expect (enumerated.end() >= enumerated.begin());
        }
    }
};
 
static EnumerateUnitTest enumerateUnitTest;
 
} // namespace juce