Class StreamSink

Source/Falcor/Testing/UnitTest.h:363–408

* StreamSink is a utility class used by the testing framework that either * captures values printed via C++'s operator<< (as with regular * std::ostreams) or discards them. (If a test has failed, then * StreamSink does the former, and if it has passed, it does the latter.) * In the event of a test failure, passes along the failure message to the * provided GPUUnitTestContext's |reportFailure

 * provided GPUUnitTestContext's |reportFailure| method.
 */
class StreamSink
{
public:
    /**
     * We need to declare this constructor in order to return
     * StreamSinks as rvalues from functions because we've declared a
     * StreamSink destructor below.
     */
    StreamSink(StreamSink&&) = default;

    /**
     * Construct a StreamSink for a test context.
     * If a non-nullptr UnitTestContext is provided, the values printed
     * will be accumulated and passed to the context's reportFailure()
     * method when the StreamSink destructor runs.
     */
    StreamSink(UnitTestContext* ctx) : mpCtx(ctx) {}

    ~StreamSink()
    {
        if (mpCtx)
            mpCtx->reportFailure(mSs.str());
    }

    void setInsertNewLine() { mInsertNewLine = true; }

    template<typename T>
    StreamSink& operator<<(T&& s)
    {
        if (mpCtx)
        {
            if (mInsertNewLine)
            {
                mSs << "\n";
                mInsertNewLine = false;
            }
            mSs << s;
        }
        return *this;
    }

private:
    std::stringstream mSs;
    UnitTestContext* mpCtx = nullptr;
    bool mInsertNewLine = false;
};

/// A test has failed when there is a failureMsg, if the value is not set, the test has passed
inline StreamSink createFullMessage(