fix(tests): enshure sort keys are unique

In tests which involve sorting by keys, we need to enshure that the keys
are not repeated.
Fixes #104

compyle/tests/test_array.py

@@ -266,8 +266,13 @@ def test_sort_by_keys(backend):
     check_import(backend)
 
     # Given
-    nparr1 = np.random.randint(0, 100, 16, dtype=np.int32)
-    nparr2 = np.random.randint(0, 100, 16, dtype=np.int32)
+    pre_nparr1 = np.random.randint(0, 100, 16, dtype=np.int32)
+    pre_nparr2 = np.random.randint(0, 100, 16, dtype=np.int32)
+
+    ## drop non unique values
+    nparr1, indices = np.unique(pre_nparr1, return_index=True)
+    nparr2 = pre_nparr2[indices]
+
     dev_array1, dev_array2 = array.wrap(nparr1, nparr2, backend=backend)
 
     # When
@@ -286,8 +291,13 @@ def test_radix_sort_by_keys():
     for use_openmp in [True, False]:
         get_config().use_openmp = use_openmp
         # Given
-        nparr1 = np.random.randint(0, 100, 16, dtype=np.int32)
-        nparr2 = np.random.randint(0, 100, 16, dtype=np.int32)
+        pre_nparr1 = np.random.randint(0, 100, 16, dtype=np.int32)
+        pre_nparr2 = np.random.randint(0, 100, 16, dtype=np.int32)
+
+        ## drop non unique values
+        nparr1, indices = np.unique(pre_nparr1, return_index=True)
+        nparr2 = pre_nparr2[indices]
+
         dev_array1, dev_array2 = array.wrap(nparr1, nparr2, backend=backend)
 
         # When
@@ -298,6 +308,8 @@ def test_radix_sort_by_keys():
         order = np.argsort(nparr1)
         act_result1 = np.take(nparr1, order)
         act_result2 = np.take(nparr2, order)
+        if not np.all(out_array1.get() == act_result1) or not np.all(out_array2.get() == act_result2):
+            print('About to fail')
         assert np.all(out_array1.get() == act_result1)
         assert np.all(out_array2.get() == act_result2)
     get_config().use_openmp = False
@@ -310,8 +322,13 @@ def test_sort_by_keys_with_output(backend):
     check_import(backend)
 
     # Given
-    nparr1 = np.random.randint(0, 100, 16, dtype=np.int32)
-    nparr2 = np.random.randint(0, 100, 16, dtype=np.int32)
+    pre_nparr1 = np.random.randint(0, 100, 16, dtype=np.int32)
+    pre_nparr2 = np.random.randint(0, 100, 16, dtype=np.int32)
+
+    ## drop non unique values
+    nparr1, indices = np.unique(pre_nparr1, return_index=True)
+    nparr2 = pre_nparr2[indices]
+
     dev_array1, dev_array2 = array.wrap(nparr1, nparr2, backend=backend)
     out_arrays = [
         array.zeros_like(dev_array1),