Oneliner for testing std::vector contents

Question

What is a more convenient way of doing this:

EXPECT_EQ(mock->params.size(), 2);
EXPECT_EQ(mock->params[0], "firstCall");
EXPECT_EQ(mock->params[1], "secondCall");

One problem with the above is that the test cases will crash when doing test driven development where the size of mock->params will first be zero before the actual code under test is written.

BTW, I am not allowed to use GoogleMock since it needs certain compiler flags which I can't use. I can use std and boost.

Answer 1

You may try to use Boost.Assign. For instance, list_of sequence can be compared with vector:

live demo

#include <iostream>
#include <ostream>
#include <vector>
#include <boost/assign/list_of.hpp>
using namespace std;
using namespace boost::assign;

int main()
{
    vector<int> v;
    v.push_back(0);
    v.push_back(1);
    cout << (v == list_of(0)(1) ) << endl;
    cout << (v == list_of(1) ) << endl;
    cout << (v == list_of(1)(2) ) << endl;
}

Output is:

1
0
0

Answer 2

Not a one liner but should do what you want:

std::vector<std::string> expected;
expected.push_back("firstCall");
expected.push_back("secondCall");
EXPECT_EQ(mock->params,expected);

Otherwise I would recommend to use ASSERT_EQ() for the first test to prevent your test case from crashing as @Rook states in his comment (that's what it's designed for).

UPDATE: Using Boost Assign as @Evgeny Panasyuk's answer suggests it should look like this:

EXPECT_EQ(mock->params,list_of("firstCall")("secondCall"));

If I understood this correctly (its not so clear from the answer, and I've personally never used this).

Answer 3

You can use Google Mock's (Google Mock is Google Test's companion mocking framework) rich library of matchers to write clear looking test assertions:

#include <gtest.h>
#include <gmock.h>

using testing::ElementsAre;

TEST(Foo, Bar) {
  EXPECT_THAT(mock->params, ElementsAre("firstCall", "secondCall"));
}

That assertion also produces clear message when the tested condition is violated.