In this HackerRank Day 27: Testing problem solution Your company needs a function that meets the following requirements:

For a given array of n integers, the function returns the index of the element with the minimum value in the array. If there is more than one element with the minimum value, it returns the smallest one.
If an empty array is passed to the function, it raises an exception. A colleague has written this method. The implementation in Python is listed below. Implementations in other languages can be found in the code template.
def minimum_index(seq):
    if len(seq) == 0:
        raise ValueError("Cannot get the minimum value index from an empty sequence")
    min_idx = 0
    for i in range(1, len(seq)):
        if a[i] < a[min_idx]:
            min_idx = i
    return min_idx
A coworker has prepared functions that will perform the tests and validate return values. Finish the implementation of 3 classes to provide data and expected results for the tests.

Complete the following methods.

In the class TestDataEmptyArray:

get_array() returns an empty array
In the class TestDataUniqueValues:

get_array() returns an array of size at least 2 with all unique elements
get_expected_result() returns the expected minimum value index for this array
In the class TestDataExactlyTwoDifferentMinimums:

get_array() returns an array where the minimum value occurs at exactly 2 indices
get_expected_result() returns the expected index
Take a look at the code template to see the exact implementation of functions that your colleague already implemented.

Note: The arrays are indexed from 0.

HackerRank Day 27: Testing problem solution

Problem solution in Python programming.

def minimum_index(seq):
    if len(seq) == 0:
        raise ValueError("Cannot get the minimum value index from an empty sequence")
    min_idx = 0
    for i in range(1, len(seq)):
        if seq[i] < seq[min_idx]:
            min_idx = i
    return min_idx

class TestDataEmptyArray(object):
    
    @staticmethod
    def get_array():
        return list()

class TestDataUniqueValues(object):
    
    @staticmethod
    def get_array():
        return [7,9,1,2,-7,10,22]
    
    @staticmethod
    def get_expected_result():
        return 4
    
class TestDataExactlyTwoDifferentMinimums(object):
    
    @staticmethod
    def get_array():
        return [7,9,1,2,-7,10,22,-7]
    
    @staticmethod
    def get_expected_result():
        return 4
    
    

def TestWithEmptyArray():
    try:
        seq = TestDataEmptyArray.get_array()
        result = minimum_index(seq)
    except ValueError as e:
        pass
    else:
        assert False


def TestWithUniqueValues():
    seq = TestDataUniqueValues.get_array()
    assert len(seq) >= 2

    assert len(list(set(seq))) == len(seq)

    expected_result = TestDataUniqueValues.get_expected_result()
    result = minimum_index(seq)
    assert result == expected_result


def TestiWithExactyTwoDifferentMinimums():
    seq = TestDataExactlyTwoDifferentMinimums.get_array()
    assert len(seq) >= 2
    tmp = sorted(seq)
    assert tmp[0] == tmp[1] and (len(tmp) == 2 or tmp[1] < tmp[2])

    expected_result = TestDataExactlyTwoDifferentMinimums.get_expected_result()
    result = minimum_index(seq)
    assert result == expected_result

TestWithEmptyArray()
TestWithUniqueValues()
TestiWithExactyTwoDifferentMinimums()
print("OK")