So I just took this from the For Example box within the instructions:

For example:

var c = new Counter();
c.incr(); // counter is now at 1
c + 1; // 2
c > 1; // false
c > 0; // true
c == 1; // true
Math.sqrt(c); // 1

Interpreted each line as a literal unit test as follows:

var c = new Counter();
Test.assertEquals(c.incr(), 1) // counter is now at 1
Test.assertEquals(c + 1, 2); // 2
Test.assertEquals(c > 1, false); // false
Test.assertEquals(c > 0, true); // true
Test.assertEquals(c == 1, true); // true
Test.assertEquals(Math.sqrt(c), 1); // 1

yields the following results:

Expected: 1, instead got: undefined
0 Passed
1 Failed
0 Errors

Process took 49ms to complete

Changing the line as mentioned to what was outlined earlier yeilds:

Test Passed: Value == 1
Test Passed: Value == 2
Test Passed: Value == false
Test Passed: Value == true
Test Passed: Value == true
Test Passed: Value == 1
6 Passed
0 Failed
0 Errors

Process took 52ms to complete

Ok, so try running the following Unit Test:

var c = new Counter();
Test.assertEquals(c.incr(), 1) // counter is now at 1

/**
Runs in console:
Expected: 1, instead got: undefined

0 Passed
1 Failed
0 Errors

Process took 47ms to complete
*/