TST: added tests for mlab.contiguous_regions

lib/matplotlib/tests/test_mlab.py

@@ -2963,6 +2963,30 @@ def test_evaluate_equal_dim_and_num_lt(self):
 
 
 #*****************************************************************
+
+def test_contiguous_regions():
+    a, b, c = 3, 4, 5
+    # Starts and ends with True
+    mask = [True]*a + [False]*b + [True]*c
+    expected = [(0, a), (a+b, a+b+c)]
+    assert_equal(mlab.contiguous_regions(mask), expected)
+    d, e = 6, 7
+    # Starts with True ends with False
+    mask = mask + [False]*e
+    assert_equal(mlab.contiguous_regions(mask), expected)
+    # Starts with False ends with True
+    mask = [False]*d + mask[:-e]
+    expected = [(d, d+a), (d+a+b, d+a+b+c)]
+    assert_equal(mlab.contiguous_regions(mask), expected)
+    # Starts and ends with False
+    mask = mask + [False]*e
+    assert_equal(mlab.contiguous_regions(mask), expected)
+    # No True in mask
+    assert_equal(mlab.contiguous_regions([False]*5), [])
+    # Empty mask
+    assert_equal(mlab.contiguous_regions([]), [])
+
+
 #*****************************************************************
 
 if __name__ == '__main__':