diff --git a/TODO b/TODO
index 7ace6a55..1945c8c3 100644
--- a/TODO
+++ b/TODO
@@ -1,4 +1,3 @@
-- similarity problems? see test_resample
 
 - add imageize from 2D arrays, eg. we should be able to write
 
diff --git a/test/Makefile.am b/test/Makefile.am
index af987e1d..c4eb9d7d 100644
--- a/test/Makefile.am
+++ b/test/Makefile.am
@@ -8,6 +8,7 @@ EXTRA_DIST = \
 	test_thumbnail.sh \
 	test_threading.sh \
 	test_python.sh
+	test_all.py \
 	test_arithmetic.py \
 	test_colour.py \
 	test_conversion.py \
@@ -20,8 +21,6 @@ EXTRA_DIST = \
 
 # don't run test_thumbnail.sh by default, it takes ages
 
-# test with python2 and python3 ... we are supposed to work with either
-
 TESTS = \
 	test_cli.sh \
 	test_formats.sh \
diff --git a/test/test_all.py b/test/test_all.py
new file mode 100755
index 00000000..8d45d7d1
--- /dev/null
+++ b/test/test_all.py
@@ -0,0 +1,17 @@
+#!/usr/bin/python3
+
+import unittest
+
+from test_arithmetic import *
+from test_colour import *
+from test_conversion import *
+from test_convolution import *
+from test_create import *
+from test_draw import *
+from test_histogram import *
+from test_morphology import *
+from test_resample import *
+
+if __name__ == '__main__':
+    unittest.main()
+
diff --git a/test/test_cli.sh b/test/test_cli.sh
index 7e10e77d..601557a7 100755
--- a/test/test_cli.sh
+++ b/test/test_cli.sh
@@ -3,7 +3,7 @@
 # this test is also in test_resample.py (though much smaller and neater) ...
 # keep this test to exercise the cli interface
 
-set -x
+# set -x
 
 . ./variables.sh
 
diff --git a/test/test_python.sh b/test/test_python.sh
index 1427dd7a..ec464471 100755
--- a/test/test_python.sh
+++ b/test/test_python.sh
@@ -10,24 +10,8 @@
 
 echo "testing with python2 ..."
 
-python2 test_arithmetic.py 
-python2 test_colour.py 
-python2 test_conversion.py 
-python2 test_convolution.py 
-python2 test_create.py
-python2 test_draw.py
-python2 test_histogram.py
-python2 test_morphology.py
-python2 test_resample.py
+python2 test_all.py 
 
 echo "testing with python3 ..."
 
-python3 test_colour.py 
-python3 test_arithmetic.py 
-python3 test_conversion.py
-python3 test_convolution.py 
-python3 test_create.py
-python3 test_draw.py
-python3 test_histogram.py
-python3 test_morphology.py
-python3 test_resample.py
+python3 test_all.py 
diff --git a/test/test_resample.py b/test/test_resample.py
index 0babd55d..ae681fce 100755
--- a/test/test_resample.py
+++ b/test/test_resample.py
@@ -41,8 +41,7 @@ class TestResample(unittest.TestCase):
             x = im
             interpolate = Vips.Interpolate.new(name)
             for i in range(4):
-                # 90 degree rotate
-                x = x.affine([0, -1, 1, 0], interpolate = interpolate)
+                x = x.affine([0, 1, 1, 0], interpolate = interpolate)
  
             self.assertEqual((x - im).abs().max(), 0)