Verify Binary Search result with duplicate target in the array

Testing scenario: If testArray contains target at position n, then binarySearch (testArray, target) must return n

public void assertTheory4(int[] testArray, int target, int returnValue)
{
  assertEquals(getTargetPosition(testArray, target), returnValue);
}

public int getTargetPosition(int[] testArray, int target) {
  for (int i = 0; i < testArray.length; i++)
    if (testArray[i] == target)
      return i;
  return -1;
}

Array=[2, 11, 36, 66, 104, 108, 108, 108, 122, 155, 159, 161, 191]

target=108

Binary Search 108 will return 6 while getTargetPosition return 5.

Possible fix

Update the function getTargetPosition to return a int array, which contains all position of the value. Then assert this return int array must contain binary search result.*

Any others?

• SECTION 7.2 OF <BEAUTIFUL CODE>