--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/tests/test_data_paginator.py	Sat Aug 16 08:15:30 2014 -0700
@@ -0,0 +1,127 @@
+import math
+import pytest
+from piecrust.data.base import IPaginationSource
+from piecrust.data.paginator import Paginator
+
+
+class MockSource(list, IPaginationSource):
+    def __init__(self, count):
+        for i in range(count):
+            self.append('item %d' % i)
+
+    def getItemsPerPage(self):
+        return 5
+
+    def getSourceIterator(self):
+        return None
+
+    def getSorterIterator(self, it):
+        return None
+
+    def getTailIterator(self, it):
+        return None
+
+    def getPaginationFilter(self, page):
+        return None
+
+
+@pytest.mark.parametrize('uri, page_num, count', [
+        ('', 1, 0),
+        ('', 1, 4),
+        ('', 1, 5),
+        ('', 1, 8),
+        ('', 1, 14),
+        ('', 2, 8),
+        ('', 2, 14),
+        ('', 3, 14),
+        ('blog', 1, 0),
+        ('blog', 1, 4),
+        ('blog', 1, 5),
+        ('blog', 1, 8),
+        ('blog', 1, 14),
+        ('blog', 2, 8),
+        ('blog', 2, 14),
+        ('blog', 3, 14)
+    ])
+def test_paginator(uri, page_num, count):
+    source = MockSource(count)
+    p = Paginator(None, source, uri, page_num)
+
+    if count <= 5:
+        # All posts fit on the page
+        assert p.prev_page_number is None
+        assert p.prev_page is None
+        assert p.this_page_number == 1
+        assert p.this_page == uri
+        assert p.next_page_number is None
+        assert p.next_page is None
+    elif page_num == 1:
+        # First page in many
+        assert p.prev_page_number is None
+        assert p.prev_page is None
+        assert p.this_page_number == 1
+        assert p.this_page == uri
+        assert p.next_page_number == 2
+        np = '2' if uri == '' else (uri + '/2')
+        assert p.next_page == np
+    else:
+        # Page in the middle of it all
+        assert p.prev_page_number == page_num - 1
+        if page_num == 2:
+            assert p.prev_page == uri
+        else:
+            pp = str(page_num - 1) if uri == '' else (
+                    '%s/%d' % (uri, page_num - 1))
+            assert p.prev_page == pp
+
+        assert p.this_page_number == page_num
+        tp = str(page_num) if uri == '' else (
+                '%s/%d' % (uri, page_num))
+        assert p.this_page == tp
+
+        if page_num * 5 > count:
+            assert p.next_page_number is None
+            assert p.next_page is None
+        else:
+            assert p.next_page_number == page_num + 1
+            np = str(page_num + 1) if uri == '' else (
+                    '%s/%d' % (uri, page_num + 1))
+            assert p.next_page == np
+
+    assert p.total_post_count == count
+    page_count = math.ceil(count / 5.0)
+    assert p.total_page_count == page_count
+    assert p.all_page_numbers() == list(range(1, page_count + 1))
+
+    for radius in range(1, 8):
+        width = radius * 2 + 1
+        if page_count == 0:
+            nums = []
+        else:
+            nums = list(filter(
+                lambda i: i >= 1 and i <= page_count,
+                range(page_num - radius, page_num + radius + 1)))
+            if len(nums) < width:
+                to_add = width - len(nums)
+                if nums[0] > 1:
+                    to_add = min(to_add, nums[0] - 1)
+                    nums = list(range(1, to_add + 1)) + nums
+                else:
+                    to_add = min(to_add, page_count - nums[-1])
+                    nums = nums + list(range(nums[-1] + 1, nums[-1] + to_add + 1))
+        assert nums == p.all_page_numbers(radius)
+
+    itp = count
+    if count > 5:
+        if page_num * 5 < count:
+            itp = 5
+        else:
+            itp = count % 5
+    assert p.items_this_page == itp
+
+    indices = list(range(count))
+    indices = indices[(page_num - 1) * 5 : (page_num - 1) * 5 + itp]
+    expected = list(['item %d' % i for i in indices])
+    items = list(p.items)
+    assert items == expected
+