def test_merge_in_file_fails(test_data_path, data_generator):
"""
Check that error is raised if argument isn't an iterable of pandas data structures.
"""
output = os.path.join(test_data_path, "merge_fail.csv")
remove_file(output)
with pytest.raises(TypeError):
merge_in_file(output, 12)
def test_to_file_fails(test_data_path, to_file_frame):
"""
Check error raises when writing to file non-pandas entity.
"""
output = os.path.join(test_data_path, "to_file.csv")
remove_file(output)
with pytest.raises(AttributeError):
to_file([1, 2, 3], test_data_path, "to_file.csv")
def test_to_file(test_data_path, to_file_frame):
"""
Check write to file works
"""
output = os.path.join(test_data_path, "to_file.csv")
remove_file(output)
to_file(to_file_frame, test_data_path, "to_file.csv")
frm = pd.read_csv(output)
assert frm["A"].sum() == 6
def test_merge_in_file(test_data_path, data_generator):
"""
Check that files can be merged in a temporary file
"""
output = os.path.join(test_data_path, "merged_data.csv")
remove_file(output)
gen = data_generator(10, 5, 2)
merge_in_file(output, gen)
frame = pd.read_csv(output)
n_cases, k = frame.shape
assert n_cases == 10 * 5
assert k == 2
def test_merge_in_file_repetition(test_data_path, data_generator):
"""
Check that files can be merged in a temporary file when function called twice.
"""
output = os.path.join(test_data_path, "merged_data.csv")
remove_file(output)
gen = data_generator(10, 5, 2)
merge_in_file(output, gen)
gen = data_generator(10, 5, 2)
merge_in_file(output, gen, delete_file=True)
frame = pd.read_csv(output)
n_cases, k = frame.shape
assert n_cases == 10 * 5
assert k == 2