Pinq\Tests\Integration\Traversable\TraversableTest::assertThatExecutionIsDeferred PHP Method

    protected final function assertThatExecutionIsDeferred(callable $traversableQuery)
    {
        $exception = new CustomException();
        $throwingFunction = function () use($exception) {
            throw $exception;
        };
        try {
            $traversable = $traversableQuery($throwingFunction);
        } catch (CustomException $thrownException) {
            $this->assertFalse(true, 'Traversable query method should not have thrown the exception');
        }
        try {
            foreach ($traversable as $key => $value) {
                $this->assertFalse(true, 'Iteration should caused the exception to be thrown');
            }
        } catch (CustomException $thrownException) {
            $this->assertSame($exception, $thrownException);
        }
    }