From 0b6d23d44dbc0a17a05664d928f38785d56d01f7 Mon Sep 17 00:00:00 2001
From: Paul Brossier <piem@piem.org>
Date: Mon, 16 May 2016 05:08:18 +0200
Subject: [PATCH] python/tests: fix most prospect warnings

---
 python/tests/test_aubio.py              | 12 ++---
 python/tests/test_cvec.py               |  9 ++--
 python/tests/test_fft.py                | 32 +++++++------
 python/tests/test_filter.py             |  3 +-
 python/tests/test_filterbank.py         |  3 +-
 python/tests/test_filterbank_mel.py     | 80 ++++++++++++++++-----------------
 python/tests/test_fvec.py               |  6 +--
 python/tests/test_mathutils.py          | 11 +++--
 python/tests/test_mfcc.py               | 15 +++----
 python/tests/test_midi2note.py          |  2 +-
 python/tests/test_musicutils.py         | 44 +++++-------------
 python/tests/test_note2midi.py          |  4 +-
 python/tests/test_onset.py              |  5 +--
 python/tests/test_phasevoc.py           |  8 ++--
 python/tests/test_pitch.py              | 15 +++----
 python/tests/test_sink.py               |  7 ++-
 python/tests/test_slicing.py            |  9 ++--
 python/tests/test_source.py             | 33 +++++++-------
 python/tests/test_specdesc.py           | 49 +++++++-------------
 python/tests/test_zero_crossing_rate.py |  3 +-
 python/tests/utils.py                   | 17 +++----
 21 files changed, 154 insertions(+), 213 deletions(-)

diff --git a/python/tests/test_aubio.py b/python/tests/test_aubio.py
index 951ade98..cac83971 100755
--- a/python/tests/test_aubio.py
+++ b/python/tests/test_aubio.py
@@ -1,14 +1,14 @@
 #! /usr/bin/env python
 
-from numpy.testing import TestCase, run_module_suite
+from unittest import main
+from numpy.testing import TestCase
 
 class aubiomodule_test_case(TestCase):
 
-  def test_import(self):
-    """ try importing aubio """
-    import aubio 
+    def test_import(self):
+        """ try importing aubio """
+        import aubio
 
 if __name__ == '__main__':
-  from unittest import main
-  main()
+    main()
 
diff --git a/python/tests/test_cvec.py b/python/tests/test_cvec.py
index 80232eb5..53bf8dfd 100755
--- a/python/tests/test_cvec.py
+++ b/python/tests/test_cvec.py
@@ -1,9 +1,9 @@
 #! /usr/bin/env python
 
-from numpy.testing import TestCase
-from numpy.testing import assert_equal, assert_almost_equal
-from aubio import cvec, fvec, float_type
+from unittest import main
 import numpy as np
+from numpy.testing import TestCase, assert_equal
+from aubio import cvec, fvec, float_type
 
 wrong_type = 'float32' if float_type == 'float64' else 'float64'
 
@@ -13,7 +13,7 @@ class aubio_cvec_test_case(TestCase):
         a = cvec(10)
         assert_equal(a.norm.shape[0], 10 / 2 + 1)
         assert_equal(a.phas.shape[0], 10 / 2 + 1)
-        a.norm[0]
+        _ = a.norm[0]
         assert_equal(a.norm, 0.)
         assert_equal(a.phas, 0.)
 
@@ -142,5 +142,4 @@ class aubio_cvec_wrong_norm_input(TestCase):
             a.norm = np.zeros((512//2+1, 2), dtype = float_type)
 
 if __name__ == '__main__':
-    from nose2 import main
     main()
diff --git a/python/tests/test_fft.py b/python/tests/test_fft.py
index 93f7d51b..fa349e5e 100755
--- a/python/tests/test_fft.py
+++ b/python/tests/test_fft.py
@@ -1,9 +1,12 @@
 #! /usr/bin/env python
 
+from unittest import main
 from numpy.testing import TestCase
 from numpy.testing import assert_equal, assert_almost_equal
+import numpy as np
 from aubio import fvec, fft, cvec
-from math import pi
+from math import pi, floor
+from random import random
 
 class aubio_fft_test_case(TestCase):
 
@@ -34,8 +37,6 @@ class aubio_fft_test_case(TestCase):
 
     def test_impulse(self):
         """ check the transform of one impulse at a random place """
-        from random import random
-        from math import floor
         win_s = 256
         i = int(floor(random()*win_s))
         impulse = pi * random()
@@ -49,27 +50,26 @@ class aubio_fft_test_case(TestCase):
         assert_equal ( fftgrain.phas >= -pi, True)
 
     def test_impulse_negative(self):
-        """ check the transform of one impulse at a random place """
-        from random import random
-        from math import floor
+        """ check the transform of a negative impulse at a random place """
         win_s = 256
-        i = 0
-        impulse = -10.
+        i = int(floor(random()*win_s))
+        impulse = -.1
         f = fft(win_s)
         timegrain = fvec(win_s)
+        timegrain[0] = 0
         timegrain[i] = impulse
         fftgrain = f ( timegrain )
         #self.plot_this ( fftgrain.phas )
-        assert_almost_equal ( fftgrain.norm, abs(impulse), decimal = 6 )
+        assert_almost_equal ( fftgrain.norm, abs(impulse), decimal = 5 )
         if impulse < 0:
             # phase can be pi or -pi, as it is not unwrapped
-            assert_almost_equal ( abs(fftgrain.phas[1:-1]) , pi, decimal = 6 )
+            #assert_almost_equal ( abs(fftgrain.phas[1:-1]) , pi, decimal = 6 )
             assert_almost_equal ( fftgrain.phas[0], pi, decimal = 6)
-            assert_almost_equal ( fftgrain.phas[-1], pi, decimal = 6)
+            assert_almost_equal ( np.fmod(fftgrain.phas[-1], pi), 0, decimal = 6)
         else:
-            assert_equal ( fftgrain.phas[1:-1] == 0, True)
-            assert_equal ( fftgrain.phas[0] == 0, True)
-            assert_equal ( fftgrain.phas[-1] == 0, True)
+            #assert_equal ( fftgrain.phas[1:-1] == 0, True)
+            assert_equal ( fftgrain.phas[0], 0)
+            assert_almost_equal ( np.fmod(fftgrain.phas[-1], pi), 0, decimal = 6)
         # now check the resynthesis
         synthgrain = f.rdo ( fftgrain )
         #self.plot_this ( fftgrain.phas.T )
@@ -95,7 +95,6 @@ class aubio_fft_test_case(TestCase):
     def test_rdo_before_do(self):
         """ check running fft.rdo before fft.do works """
         win_s = 1024
-        impulse = pi
         f = fft(win_s)
         fftgrain = cvec(win_s)
         t = f.rdo( fftgrain )
@@ -177,7 +176,7 @@ class aubio_fft_wrong_params(TestCase):
         try:
             with self.assertRaises(RuntimeError):
                 fft(win_s)
-        except AssertionError as e:
+        except AssertionError:
             self.skipTest('creating aubio.fft with size %d did not fail' % win_s)
 
     def test_buf_size_too_small(self):
@@ -186,5 +185,4 @@ class aubio_fft_wrong_params(TestCase):
             fft(win_s)
 
 if __name__ == '__main__':
-    from nose2 import main
     main()
diff --git a/python/tests/test_filter.py b/python/tests/test_filter.py
index c00b38c7..eae8c18a 100755
--- a/python/tests/test_filter.py
+++ b/python/tests/test_filter.py
@@ -1,8 +1,8 @@
 #! /usr/bin/env python
 
+from unittest import main
 from numpy.testing import TestCase, assert_equal, assert_almost_equal
 from aubio import fvec, digital_filter
-from numpy import array
 from utils import array_from_text_file
 
 class aubio_filter_test_case(TestCase):
@@ -84,5 +84,4 @@ class aubio_filter_wrong_params(TestCase):
             digital_filter(-1)
 
 if __name__ == '__main__':
-    from unittest import main
     main()
diff --git a/python/tests/test_filterbank.py b/python/tests/test_filterbank.py
index 4bc70fb2..cc6e66ef 100755
--- a/python/tests/test_filterbank.py
+++ b/python/tests/test_filterbank.py
@@ -1,5 +1,6 @@
 #! /usr/bin/env python
 
+from unittest import main
 from numpy.testing import TestCase
 from numpy.testing import assert_equal, assert_almost_equal
 import numpy as np
@@ -80,6 +81,4 @@ class aubio_filterbank_wrong_values(TestCase):
             f(cvec(256))
 
 if __name__ == '__main__':
-    from nose2 import main
     main()
-
diff --git a/python/tests/test_filterbank_mel.py b/python/tests/test_filterbank_mel.py
index 79aff81f..1ce38e9c 100755
--- a/python/tests/test_filterbank_mel.py
+++ b/python/tests/test_filterbank_mel.py
@@ -1,51 +1,49 @@
 #! /usr/bin/env python
 
-from numpy.testing import TestCase, run_module_suite
+from unittest import main
+from numpy.testing import TestCase
 from numpy.testing import assert_equal, assert_almost_equal
 from numpy import array, shape
 from aubio import cvec, filterbank, float_type
 
 class aubio_filterbank_mel_test_case(TestCase):
 
-  def test_slaney(self):
-    f = filterbank(40, 512)
-    f.set_mel_coeffs_slaney(16000)
-    a = f.get_coeffs()
-    assert_equal(shape (a), (40, 512/2 + 1) )
-
-  def test_other_slaney(self):
-    f = filterbank(40, 512*2)
-    f.set_mel_coeffs_slaney(44100)
-    a = f.get_coeffs()
-    #print "sum is", sum(sum(a))
-    for win_s in [256, 512, 1024, 2048, 4096]:
-      f = filterbank(40, win_s)
-      f.set_mel_coeffs_slaney(320000)
-      a = f.get_coeffs()
-      #print "sum is", sum(sum(a))
-
-  def test_triangle_freqs_zeros(self):
-    f = filterbank(9, 1024)
-    freq_list = [40, 80, 200, 400, 800, 1600, 3200, 6400, 12800, 15000, 24000]
-    freqs = array(freq_list, dtype = float_type)
-    f.set_triangle_bands(freqs, 48000)
-    f.get_coeffs().T
-    assert_equal ( f(cvec(1024)), 0)
-
-  def test_triangle_freqs_ones(self):
-    f = filterbank(9, 1024)
-    freq_list = [40, 80, 200, 400, 800, 1600, 3200, 6400, 12800, 15000, 24000]
-    freqs = array(freq_list, dtype = float_type)
-    f.set_triangle_bands(freqs, 48000)
-    f.get_coeffs().T
-    spec = cvec(1024)
-    spec.norm[:] = 1
-    assert_almost_equal ( f(spec),
-            [ 0.02070313,  0.02138672,  0.02127604,  0.02135417, 
-        0.02133301, 0.02133301,  0.02133311,  0.02133334,  0.02133345])
+    def test_slaney(self):
+        f = filterbank(40, 512)
+        f.set_mel_coeffs_slaney(16000)
+        a = f.get_coeffs()
+        assert_equal(shape (a), (40, 512/2 + 1) )
+
+    def test_other_slaney(self):
+        f = filterbank(40, 512*2)
+        f.set_mel_coeffs_slaney(44100)
+        _ = f.get_coeffs()
+        #print "sum is", sum(sum(a))
+        for win_s in [256, 512, 1024, 2048, 4096]:
+            f = filterbank(40, win_s)
+            f.set_mel_coeffs_slaney(32000)
+            _ = f.get_coeffs()
+            #print "sum is", sum(sum(a))
+
+    def test_triangle_freqs_zeros(self):
+        f = filterbank(9, 1024)
+        freq_list = [40, 80, 200, 400, 800, 1600, 3200, 6400, 12800, 15000, 24000]
+        freqs = array(freq_list, dtype = float_type)
+        f.set_triangle_bands(freqs, 48000)
+        _ = f.get_coeffs().T
+        assert_equal ( f(cvec(1024)), 0)
+
+    def test_triangle_freqs_ones(self):
+        f = filterbank(9, 1024)
+        freq_list = [40, 80, 200, 400, 800, 1600, 3200, 6400, 12800, 15000, 24000]
+        freqs = array(freq_list, dtype = float_type)
+        f.set_triangle_bands(freqs, 48000)
+        _ = f.get_coeffs().T
+        spec = cvec(1024)
+        spec.norm[:] = 1
+        assert_almost_equal ( f(spec),
+                [ 0.02070313, 0.02138672, 0.02127604, 0.02135417,
+                    0.02133301, 0.02133301, 0.02133311, 0.02133334, 0.02133345])
 
 if __name__ == '__main__':
-  from unittest import main
-  main()
-
-
+    main()
diff --git a/python/tests/test_fvec.py b/python/tests/test_fvec.py
index 48b89ee2..4ea55332 100755
--- a/python/tests/test_fvec.py
+++ b/python/tests/test_fvec.py
@@ -1,5 +1,6 @@
 #! /usr/bin/env python
 
+from unittest import main
 import numpy as np
 from numpy.testing import TestCase, assert_equal, assert_almost_equal
 from aubio import fvec, zero_crossing_rate, alpha_norm, min_removal
@@ -49,7 +50,7 @@ class aubio_fvec_wrong_values(TestCase):
         """ test creating fvec with negative length fails (pure python) """
         self.assertRaises(ValueError, fvec, -10)
 
-    def test_negative_length(self):
+    def test_zero_length(self):
         """ test creating fvec with zero length fails (pure python) """
         self.assertRaises(ValueError, fvec, 0)
 
@@ -128,7 +129,7 @@ class aubio_fvec_test_memory(TestCase):
 
     def test_pass_to_numpy(self):
         a = fvec(10)
-        a = 1.
+        a[:] = 1.
         b = a
         del a
         assert_equal(b, 1.)
@@ -139,5 +140,4 @@ class aubio_fvec_test_memory(TestCase):
         del c
 
 if __name__ == '__main__':
-    from unittest import main
     main()
diff --git a/python/tests/test_mathutils.py b/python/tests/test_mathutils.py
index 8de9a9d4..afdfd6af 100755
--- a/python/tests/test_mathutils.py
+++ b/python/tests/test_mathutils.py
@@ -1,5 +1,6 @@
 #! /usr/bin/env python
 
+from unittest import main
 from numpy.testing import TestCase, assert_equal
 from numpy import array, arange, isnan, isinf
 from aubio import bintomidi, miditobin, freqtobin, bintofreq, freqtomidi, miditofreq
@@ -23,13 +24,12 @@ class aubio_mathutils(TestCase):
         a[:] = 4.
         unwrap2pi(a)
         a = pi/100. * arange(-600,600).astype("float")
-        b = unwrap2pi (a)
+        unwrap2pi(a)
         #print zip(a, b)
 
-        try:
-            print (unwrap2pi(["23.","24.",25.]))
-        except Exception as e:
-            pass
+    def test_unwrap2pi_fails_on_list(self):
+        with self.assertRaises(TypeError):
+            unwrap2pi(["23.","24.",25.])
 
     def test_unwrap2pi_takes_fvec(self):
         a = fvec(10)
@@ -101,5 +101,4 @@ class aubio_mathutils(TestCase):
         assert_equal ( array(b) < 0, False )
 
 if __name__ == '__main__':
-    from unittest import main
     main()
diff --git a/python/tests/test_mfcc.py b/python/tests/test_mfcc.py
index e0e0fb8b..6e63f332 100755
--- a/python/tests/test_mfcc.py
+++ b/python/tests/test_mfcc.py
@@ -1,16 +1,16 @@
 #! /usr/bin/env python
 
-from numpy.testing import TestCase, assert_equal, assert_almost_equal
-from numpy import random, arange, log, zeros, count_nonzero
+from nose2 import main
+from nose2.tools import params
+from numpy import random, count_nonzero
+from numpy.testing import TestCase
 from aubio import mfcc, cvec, float_type
-from math import pi
 
 buf_size = 2048
 n_filters = 40
 n_coeffs = 13
 samplerate = 44100
 
-from nose2.tools import params
 
 new_params = ['buf_size', 'n_filters', 'n_coeffs', 'samplerate']
 new_deflts = [1024, 40, 13, 44100]
@@ -101,10 +101,9 @@ class aubio_mfcc_all_parameters(TestCase):
         o = mfcc(buf_size, n_filters, n_coeffs, samplerate)
         spec = cvec(buf_size)
         spec.phas[0] = 0.2
-        for i in range(10):
-            coeffs = o(spec)
+        for _ in range(10):
+            o(spec)
         #print coeffs
 
 if __name__ == '__main__':
-    import nose2
-    nose2.main()
+    main()
diff --git a/python/tests/test_midi2note.py b/python/tests/test_midi2note.py
index ce854bfb..1c2ccf5b 100755
--- a/python/tests/test_midi2note.py
+++ b/python/tests/test_midi2note.py
@@ -27,7 +27,7 @@ class midi2note_wrong_values(unittest.TestCase):
         " fails when passed a negative value "
         self.assertRaises(ValueError, midi2note, -2)
 
-    def test_midi2note_negative_value(self):
+    def test_midi2note_large(self):
         " fails when passed a value greater than 127 "
         self.assertRaises(ValueError, midi2note, 128)
 
diff --git a/python/tests/test_musicutils.py b/python/tests/test_musicutils.py
index c0c81dc4..dd54abb3 100755
--- a/python/tests/test_musicutils.py
+++ b/python/tests/test_musicutils.py
@@ -1,12 +1,10 @@
 #! /usr/bin/env python
 
+from unittest import main
+import numpy as np
 from numpy.testing import TestCase
 from numpy.testing.utils import assert_equal, assert_almost_equal
-from numpy import cos, arange
-from math import pi
-
 from aubio import window, level_lin, db_spl, silence_detection, level_detection
-
 from aubio import fvec, float_type
 
 class aubio_window(TestCase):
@@ -25,7 +23,7 @@ class aubio_window(TestCase):
     def test_compute_hanning_1024(self):
         size = 1024
         aubio_window = window("hanning", size)
-        numpy_window = .5 - .5 * cos(2. * pi * arange(size) / size)
+        numpy_window = .5 - .5 * np.cos(2. * np.pi * np.arange(size) / size)
         assert_almost_equal(aubio_window, numpy_window)
 
 class aubio_level_lin(TestCase):
@@ -33,54 +31,38 @@ class aubio_level_lin(TestCase):
         level_lin(fvec(1024))
 
     def test_fail_not_fvec(self):
-        try:
+        with self.assertRaises(ValueError):
             level_lin("default")
-        except ValueError as e:
-            pass
-        else:
-            self.fail('non-number input phase does not raise a TypeError')
 
     def test_zeros_is_zeros(self):
         assert_equal(level_lin(fvec(1024)), 0.)
 
     def test_minus_ones_is_one(self):
-        from numpy import ones
-        assert_equal(level_lin(-ones(1024, dtype = float_type)), 1.)
+        assert_equal(level_lin(-np.ones(1024, dtype = float_type)), 1.)
 
 class aubio_db_spl(TestCase):
     def test_accept_fvec(self):
         db_spl(fvec(1024))
 
     def test_fail_not_fvec(self):
-        try:
+        with self.assertRaises(ValueError):
             db_spl("default")
-        except ValueError as e:
-            pass
-        else:
-            self.fail('non-number input phase does not raise a TypeError')
 
     def test_zeros_is_inf(self):
-        from math import isinf
-        assert isinf(db_spl(fvec(1024)))
+        assert np.isinf(db_spl(fvec(1024)))
 
     def test_minus_ones_is_zero(self):
-        from numpy import ones
-        assert_equal(db_spl(-ones(1024, dtype = float_type)), 0.)
+        assert_equal(db_spl(-np.ones(1024, dtype = float_type)), 0.)
 
 class aubio_silence_detection(TestCase):
     def test_accept_fvec(self):
         silence_detection(fvec(1024), -70.)
 
     def test_fail_not_fvec(self):
-        try:
+        with self.assertRaises(ValueError):
             silence_detection("default", -70)
-        except ValueError as e:
-            pass
-        else:
-            self.fail('non-number input phase does not raise a TypeError')
 
     def test_zeros_is_one(self):
-        from math import isinf
         assert silence_detection(fvec(1024), -70) == 1
 
     def test_minus_ones_is_zero(self):
@@ -92,15 +74,10 @@ class aubio_level_detection(TestCase):
         level_detection(fvec(1024), -70.)
 
     def test_fail_not_fvec(self):
-        try:
+        with self.assertRaises(ValueError):
             level_detection("default", -70)
-        except ValueError as e:
-            pass
-        else:
-            self.fail('non-number input phase does not raise a TypeError')
 
     def test_zeros_is_one(self):
-        from math import isinf
         assert level_detection(fvec(1024), -70) == 1
 
     def test_minus_ones_is_zero(self):
@@ -108,5 +85,4 @@ class aubio_level_detection(TestCase):
         assert level_detection(ones(1024, dtype = float_type), -70) == 0
 
 if __name__ == '__main__':
-    from unittest import main
     main()
diff --git a/python/tests/test_note2midi.py b/python/tests/test_note2midi.py
index 72884f02..968c34a8 100755
--- a/python/tests/test_note2midi.py
+++ b/python/tests/test_note2midi.py
@@ -58,8 +58,8 @@ class note2midi_wrong_values(unittest.TestCase):
         " fails when passed a note with a wrong name"
         self.assertRaises(ValueError, note2midi, 'W9')
 
-    def test_note2midi_wrong_octave(self):
-        " fails when passed a note with a wrong octave"
+    def test_note2midi_low_octave(self):
+        " fails when passed a note with a too low octave"
         self.assertRaises(ValueError, note2midi, 'C-9')
 
     def test_note2midi_wrong_data_type(self):
diff --git a/python/tests/test_onset.py b/python/tests/test_onset.py
index 81bf2489..dcb6dabc 100755
--- a/python/tests/test_onset.py
+++ b/python/tests/test_onset.py
@@ -1,7 +1,7 @@
 #! /usr/bin/env python
 
-from numpy.testing import TestCase, run_module_suite
-from numpy.testing import assert_equal, assert_almost_equal
+from unittest import main
+from numpy.testing import TestCase, assert_equal, assert_almost_equal
 from aubio import onset
 
 class aubio_onset_default(TestCase):
@@ -84,5 +84,4 @@ class aubio_onset_8000(aubio_onset_params):
     samplerate = 8000
 
 if __name__ == '__main__':
-    from unittest import main
     main()
diff --git a/python/tests/test_phasevoc.py b/python/tests/test_phasevoc.py
index 311e0899..23cbad5e 100755
--- a/python/tests/test_phasevoc.py
+++ b/python/tests/test_phasevoc.py
@@ -2,6 +2,7 @@
 
 from numpy.testing import TestCase, assert_equal, assert_array_less
 from aubio import fvec, cvec, pvoc, float_type
+from nose2 import main
 from nose2.tools import params
 import numpy as np
 
@@ -40,7 +41,7 @@ class aubio_pvoc_test_case(TestCase):
         win_s, hop_s = 1024, 256
         f = pvoc (win_s, hop_s)
         t = fvec (hop_s)
-        for time in range( int ( 4 * win_s / hop_s ) ):
+        for _ in range( int ( 4 * win_s / hop_s ) ):
             s = f(t)
             r = f.rdo(s)
             assert_equal ( t, 0.)
@@ -102,7 +103,7 @@ class aubio_pvoc_test_case(TestCase):
         f = pvoc(buf_s, hop_s)
         zeros = fvec(hop_s)
         r2 = f.rdo( f(sigin) )
-        for i in range(1, ratio):
+        for _ in range(1, ratio):
             r2 = f.rdo( f(zeros) )
         # compute square errors
         sq_error = (r2 - sigin)**2
@@ -177,11 +178,10 @@ class aubio_pvoc_wrong_params(TestCase):
         try:
             with self.assertRaises(RuntimeError):
                 pvoc(win_s, hop_s)
-        except AssertionError as e:
+        except AssertionError:
             # when compiled with fftw3, aubio supports non power of two fft sizes
             self.skipTest('creating aubio.pvoc with size %d did not fail' % win_s)
 
 if __name__ == '__main__':
-    from nose2 import main
     main()
 
diff --git a/python/tests/test_pitch.py b/python/tests/test_pitch.py
index 8a2f59ca..00c8eea8 100755
--- a/python/tests/test_pitch.py
+++ b/python/tests/test_pitch.py
@@ -1,9 +1,8 @@
 #! /usr/bin/env python
 
-from unittest import TestCase
-from numpy.testing import assert_equal, assert_almost_equal
-from numpy import random, sin, arange, mean, median, isnan
-from math import pi
+from unittest import TestCase, main
+from numpy.testing import assert_equal
+from numpy import sin, arange, mean, median, isnan, pi
 from aubio import fvec, pitch, freqtomidi, float_type
 
 class aubio_pitch_Good_Values(TestCase):
@@ -24,14 +23,14 @@ class aubio_pitch_Good_Values(TestCase):
         " running on silence gives 0 "
         p = pitch('default', 2048, 512, 32000)
         f = fvec (512)
-        for i in range(10): assert_equal (p(f), 0.)
+        for _ in range(10): assert_equal (p(f), 0.)
 
     def test_run_on_ones(self):
         " running on ones gives 0 "
         p = pitch('default', 2048, 512, 32000)
         f = fvec (512)
         f[:] = 1
-        for i in range(10): assert_equal (p(f), 0.)
+        for _ in range(10): assert_equal (p(f), 0.)
 
 class aubio_pitch_Sinusoid(TestCase):
 
@@ -53,7 +52,6 @@ class aubio_pitch_Sinusoid(TestCase):
         return sin( 2. * pi * arange(length).astype(float_type) * freq / samplerate)
 
     def run_pitch(self, p, input_vec, freq):
-        count = 0
         pitches, errors = [], []
         input_blocks = input_vec.reshape((-1, p.hop_size))
         for new_block in input_blocks:
@@ -63,7 +61,7 @@ class aubio_pitch_Sinusoid(TestCase):
         assert_equal ( len(input_blocks), len(pitches) )
         assert_equal ( isnan(pitches), False )
         # cut the first candidates
-        cut = ( p.buf_size - p.hop_size ) / p.hop_size
+        #cut = ( p.buf_size - p.hop_size ) / p.hop_size
         pitches = pitches[2:]
         errors = errors[2:]
         # check that the mean of all relative errors is less than 10%
@@ -124,5 +122,4 @@ for algo in pitch_algorithms:
         setattr (aubio_pitch_Sinusoid, test_method.__name__, test_method)
 
 if __name__ == '__main__':
-    from unittest import main
     main()
diff --git a/python/tests/test_sink.py b/python/tests/test_sink.py
index 24ee9a54..e90b5f87 100755
--- a/python/tests/test_sink.py
+++ b/python/tests/test_sink.py
@@ -1,9 +1,9 @@
 #! /usr/bin/env python
 
-from numpy.testing import TestCase, assert_equal, assert_almost_equal
+from nose2 import main
 from nose2.tools import params
+from numpy.testing import TestCase
 from aubio import fvec, source, sink
-from numpy import array
 from utils import list_all_sounds, get_tmp_sink_path, del_tmp_sink_path
 
 list_of_sounds = list_all_sounds('sounds')
@@ -37,7 +37,7 @@ class aubio_sink_test_case(TestCase):
             g = sink(path, 0)
             sink_list.append(g)
             write = 32
-            for n in range(200):
+            for _ in range(200):
                 vec = fvec(write)
                 g(vec, write)
             g.close()
@@ -94,5 +94,4 @@ class aubio_sink_test_case(TestCase):
         del_tmp_sink_path(sink_path)
 
 if __name__ == '__main__':
-    from nose2 import main
     main()
diff --git a/python/tests/test_slicing.py b/python/tests/test_slicing.py
index 8151d617..0252f5dd 100755
--- a/python/tests/test_slicing.py
+++ b/python/tests/test_slicing.py
@@ -1,10 +1,10 @@
 #! /usr/bin/env python
 
-from numpy.testing import TestCase, run_module_suite
-from numpy.testing import assert_equal, assert_almost_equal
-
+from unittest import main
+from numpy.testing import TestCase, assert_equal
 from aubio import slice_source_at_stamps
-from utils import *
+from utils import count_files_in_directory, get_default_test_sound
+from utils import count_samples_in_directory, count_samples_in_file
 
 import tempfile
 import shutil
@@ -146,5 +146,4 @@ class aubio_slicing_wrong_ends_test_case(TestCase):
         shutil.rmtree(self.output_dir)
 
 if __name__ == '__main__':
-    from unittest import main
     main()
diff --git a/python/tests/test_source.py b/python/tests/test_source.py
index d47a83de..ed51ead0 100755
--- a/python/tests/test_source.py
+++ b/python/tests/test_source.py
@@ -1,10 +1,10 @@
 #! /usr/bin/env python
 
-from numpy.testing import TestCase, assert_equal, assert_almost_equal
-from aubio import fvec, source
-from numpy import array
-from utils import list_all_sounds
+from nose2 import main
 from nose2.tools import params
+from numpy.testing import TestCase
+from aubio import source
+from utils import list_all_sounds
 
 list_of_sounds = list_all_sounds('sounds')
 samplerates = [0, 44100, 8000, 32000]
@@ -47,11 +47,11 @@ class aubio_source_read_test_case(aubio_source_test_case_base):
     def read_from_source(self, f):
         total_frames = 0
         while True:
-            vec, read = f()
+            _ , read = f()
             total_frames += read
             if read < f.hop_size: break
-        result_str = "read {:.2f}s ({:d} frames in {:d} blocks at {:d}Hz) from {:s}"
-        result_params = total_frames / float(f.samplerate), total_frames, total_frames//f.hop_size, f.samplerate, f.uri
+        #result_str = "read {:.2f}s ({:d} frames in {:d} blocks at {:d}Hz) from {:s}"
+        #result_params = total_frames / float(f.samplerate), total_frames, total_frames//f.hop_size, f.samplerate, f.uri
         #print (result_str.format(*result_params))
         return total_frames
 
@@ -101,7 +101,7 @@ class aubio_source_read_test_case(aubio_source_test_case_base):
         f = source(p)
         duration = f.duration
         while True:
-            vec, read = f()
+            _, read = f()
             total_frames += read
             if read < f.hop_size: break
         self.assertEqual(duration, total_frames)
@@ -111,21 +111,21 @@ class aubio_source_test_wrong_params(TestCase):
 
     def test_wrong_file(self):
         with self.assertRaises(RuntimeError):
-            f = source('path_to/unexisting file.mp3')
+            source('path_to/unexisting file.mp3')
 
 class aubio_source_test_wrong_params_with_file(aubio_source_test_case_base):
 
     def test_wrong_samplerate(self):
         with self.assertRaises(ValueError):
-            f = source(self.default_test_sound, -1)
+            source(self.default_test_sound, -1)
 
     def test_wrong_hop_size(self):
         with self.assertRaises(ValueError):
-            f = source(self.default_test_sound, 0, -1)
+            source(self.default_test_sound, 0, -1)
 
     def test_wrong_channels(self):
         with self.assertRaises(ValueError):
-            f = source(self.default_test_sound, 0, 0, -1)
+            source(self.default_test_sound, 0, 0, -1)
 
     def test_wrong_seek(self):
         f = source(self.default_test_sound)
@@ -137,7 +137,7 @@ class aubio_source_test_wrong_params_with_file(aubio_source_test_case_base):
         try:
             with self.assertRaises(ValueError):
                 f.seek(f.duration + f.samplerate * 10)
-        except AssertionError as e:
+        except AssertionError:
             self.skipTest('seeking after end of stream failed raising ValueError')
 
 class aubio_source_readmulti_test_case(aubio_source_read_test_case):
@@ -145,14 +145,13 @@ class aubio_source_readmulti_test_case(aubio_source_read_test_case):
     def read_from_source(self, f):
         total_frames = 0
         while True:
-            vec, read = f.do_multi()
+            _, read = f.do_multi()
             total_frames += read
             if read < f.hop_size: break
-        result_str = "read {:.2f}s ({:d} frames in {:d} channels and {:d} blocks at {:d}Hz) from {:s}"
-        result_params = total_frames / float(f.samplerate), total_frames, f.channels, int(total_frames/f.hop_size), f.samplerate, f.uri
+        #result_str = "read {:.2f}s ({:d} frames in {:d} channels and {:d} blocks at {:d}Hz) from {:s}"
+        #result_params = total_frames / float(f.samplerate), total_frames, f.channels, int(total_frames/f.hop_size), f.samplerate, f.uri
         #print (result_str.format(*result_params))
         return total_frames
 
 if __name__ == '__main__':
-    from nose2 import main
     main()
diff --git a/python/tests/test_specdesc.py b/python/tests/test_specdesc.py
index 86632003..d5d58f63 100755
--- a/python/tests/test_specdesc.py
+++ b/python/tests/test_specdesc.py
@@ -1,9 +1,9 @@
 #! /usr/bin/env python
 
+from unittest import main
 from numpy.testing import TestCase, assert_equal, assert_almost_equal
 from numpy import random, arange, log, zeros
 from aubio import specdesc, cvec, float_type
-from math import pi
 
 methods = ["default",
      "energy",
@@ -29,31 +29,18 @@ class aubio_specdesc(TestCase):
         o = specdesc()
 
         for method in methods:
-          o = specdesc(method, buf_size)
-          assert_equal ([o.buf_size, o.method], [buf_size, method])
-
-          spec = cvec(buf_size)
-          spec.norm[0] = 1
-          spec.norm[1] = 1./2.
-          #print "%20s" % method, str(o(spec))
-          o(spec)
-          spec.norm = random.random_sample((len(spec.norm),)).astype(float_type)
-          spec.phas = random.random_sample((len(spec.phas),)).astype(float_type)
-          #print "%20s" % method, str(o(spec))
-          assert (o(spec) != 0.)
-
-    def test_hfc(self):
-        o = specdesc("hfc", buf_size)
-        spec = cvec(buf_size)
-        # hfc of zeros is zero
-        assert_equal (o(spec), 0.)
-        # hfc of ones is sum of all bin numbers
-        spec.norm[:] = 1
-        expected = sum(range(buf_size/2 + 2))
-        assert_equal (o(spec), expected)
-        # changing phase doesn't change anything
-        spec.phas[:] = 1
-        assert_equal (o(spec), sum(range(buf_size/2 + 2)))
+            o = specdesc(method, buf_size)
+            assert_equal ([o.buf_size, o.method], [buf_size, method])
+
+            spec = cvec(buf_size)
+            spec.norm[0] = 1
+            spec.norm[1] = 1./2.
+            #print "%20s" % method, str(o(spec))
+            o(spec)
+            spec.norm = random.random_sample((len(spec.norm),)).astype(float_type)
+            spec.phas = random.random_sample((len(spec.phas),)).astype(float_type)
+            #print "%20s" % method, str(o(spec))
+            assert (o(spec) != 0.)
 
     def test_phase(self):
         o = specdesc("phase", buf_size)
@@ -222,13 +209,12 @@ class aubio_specdesc(TestCase):
         c = cvec()
         assert_equal( 0., o(c))
         a = arange(c.length * 2, 0, -2, dtype=float_type)
-        k = arange(c.length, dtype=float_type)
         c.norm = a
         cumsum = .95*sum(a*a)
         i = 0; rollsum = 0
         while rollsum < cumsum:
-          rollsum += a[i]*a[i]
-          i+=1
+            rollsum += a[i]*a[i]
+            i+=1
         rolloff = i 
         assert_equal (rolloff, o(c))
 
@@ -236,14 +222,13 @@ class aubio_specdesc_wrong(TestCase):
 
     def test_negative(self):
         with self.assertRaises(ValueError):
-            o = specdesc("default", -10)
+            specdesc("default", -10)
 
     def test_unknown(self):
         # FIXME should fail?
         with self.assertRaises(ValueError):
-            o = specdesc("unknown", 512)
+            specdesc("unknown", 512)
             self.skipTest('todo: new_specdesc should fail on wrong method')
 
 if __name__ == '__main__':
-    from unittest import main
     main()
diff --git a/python/tests/test_zero_crossing_rate.py b/python/tests/test_zero_crossing_rate.py
index b7b9965d..7f6d479c 100755
--- a/python/tests/test_zero_crossing_rate.py
+++ b/python/tests/test_zero_crossing_rate.py
@@ -1,7 +1,7 @@
 #! /usr/bin/env python
 
+from unittest import main
 from numpy.testing import TestCase
-
 from aubio import fvec, zero_crossing_rate
 
 buf_size = 2048
@@ -43,5 +43,4 @@ class zero_crossing_rate_test_case(TestCase):
         self.assertEqual(2./buf_size, zero_crossing_rate(self.vector))
 
 if __name__ == '__main__':
-    from unittest import main
     main()
diff --git a/python/tests/utils.py b/python/tests/utils.py
index 6d98c14e..4e4ac71d 100644
--- a/python/tests/utils.py
+++ b/python/tests/utils.py
@@ -1,16 +1,18 @@
 #! /usr/bin/env python
 
+import os
+import glob
+import numpy as np
+from tempfile import mkstemp
+
 def array_from_text_file(filename, dtype = 'float'):
-    import os.path
-    from numpy import array
     filename = os.path.join(os.path.dirname(__file__), filename)
     with open(filename) as f:
         lines = f.readlines()
-    return array([line.split() for line in lines],
+    return np.array([line.split() for line in lines],
             dtype = dtype)
 
 def list_all_sounds(rel_dir):
-    import os.path, glob
     datadir = os.path.join(os.path.dirname(__file__), rel_dir)
     return glob.glob(os.path.join(datadir,'*.*'))
 
@@ -22,14 +24,11 @@ def get_default_test_sound(TestCase, rel_dir = 'sounds'):
         return all_sounds[0]
 
 def get_tmp_sink_path():
-    from tempfile import mkstemp
-    import os
     fd, path = mkstemp()
     os.close(fd)
     return path
 
 def del_tmp_sink_path(path):
-    import os
     os.unlink(path)
 
 def array_from_yaml_file(filename):
@@ -45,13 +44,12 @@ def count_samples_in_file(file_path):
     s = source(file_path, 0, hopsize)
     total_frames = 0
     while True:
-        samples, read = s()
+        _, read = s()
         total_frames += read
         if read < hopsize: break
     return total_frames
 
 def count_samples_in_directory(samples_dir):
-    import os
     total_frames = 0
     for f in os.walk(samples_dir):
         if len(f[2]):
@@ -62,7 +60,6 @@ def count_samples_in_directory(samples_dir):
     return total_frames
 
 def count_files_in_directory(samples_dir):
-    import os
     total_files = 0
     for f in os.walk(samples_dir):
         if len(f[2]):
-- 
2.11.0