def test_identicalStartingAndEndingPositions():
'''
Test whether the starting and ending positions are identical
'''
with assert_raises(ValueError):
assert plotGreenDistribution('London', 'London', 9, 'out.png')
def test_emptyEndingPosition():
'''
Test whether the ending position is an empty string
'''
with assert_raises(ValueError):
assert plotGreenDistribution('London', '', 9, 'out.png')
def test_emptyOutputFilename():
'''
Test whether the filename of the output graph is an empty string
'''
with assert_raises(ValueError):
assert plotGreenDistribution('London', 'Cambridge', 9, '')
def test_negativeSteps():
'''
Test whether the steps variable is always positive
'''
with assert_raises(ValueError):
assert plotGreenDistribution('London', 'Cambridge', -5, 'out.png')
def test_emptyStartingPosition():
'''
Test whether the starting position is an empty string
'''
with assert_raises(ValueError):
assert plotGreenDistribution('', 'Cambridge', 9, 'out.png')
def test_wrongTypeOutFile():
'''
Test whether the output filename is a string
'''
with assert_raises(ValueError):
assert plotGreenDistribution('London','Cambridge', 5, 555)
def test_wrongTypeEndPos():
'''
Test whether the ending position is a string
'''
with assert_raises(ValueError):
assert plotGreenDistribution('Cambridge',(51.23,-1.2), 5, 'out.png')
def test_wrongTypeSteps():
'''
Test whether the steps variable is an integer
'''
with assert_raises(ValueError):
assert plotGreenDistribution('London', 'Cambridge', '5', 'out.png')
