initial implementations of python v3 utility functions

python/test/test_tile.py

@@ -0,0 +1,60 @@
+import unittest
+from pmtiles.tile import zxy_to_tileid, tileid_to_zxy, Entry, find_tile
+
+
+class TestTileId(unittest.TestCase):
+    def test_zxy_to_tileid(self):
+        self.assertEqual(zxy_to_tileid(0, 0, 0), 0)
+        self.assertEqual(zxy_to_tileid(1, 0, 0), 1)
+        self.assertEqual(zxy_to_tileid(1, 0, 1), 2)
+        self.assertEqual(zxy_to_tileid(1, 1, 1), 3)
+        self.assertEqual(zxy_to_tileid(1, 1, 0), 4)
+        self.assertEqual(zxy_to_tileid(2, 0, 0), 5)
+
+    def test_tileid_to_zxy(self):
+        self.assertEqual(tileid_to_zxy(0), (0, 0, 0))
+        self.assertEqual(tileid_to_zxy(1), (1, 0, 0))
+        self.assertEqual(tileid_to_zxy(19078479), (12, 3423, 1763))
+
+    def test_many_tiles(self):
+        for z in range(0, 7):
+            for x in range(0, 1 << z):
+                for y in range(0, 1 << z):
+                    i = zxy_to_tileid(z, x, y)
+                    rz, rx, ry = tileid_to_zxy(i)
+                    self.assertEqual(z, rz)
+                    self.assertEqual(x, rx)
+                    self.assertEqual(y, ry)
+
+
+class TestFindTile(unittest.TestCase):
+    def test_find_tile_missing(self):
+        entries = []
+        result = find_tile(entries, 0)
+        self.assertEqual(result, None)
+
+    def test_find_tile_first(self):
+        entries = [Entry(100, 1, 1, 1)]
+        result = find_tile(entries, 100)
+        self.assertEqual(result.offset, 1)
+        self.assertEqual(result.length, 1)
+
+    def test_find_tile_multiple(self):
+        entries = [Entry(100, 1, 1, 2)]
+        result = find_tile(entries, 101)
+        self.assertEqual(result.offset, 1)
+        self.assertEqual(result.length, 1)
+        entries = [Entry(100, 1, 1, 2), Entry(150, 2, 2, 2)]
+        result = find_tile(entries, 151)
+        self.assertEqual(result.offset, 2)
+        self.assertEqual(result.length, 2)
+        entries = [Entry(50, 1, 1, 2), Entry(100, 2, 2, 1), Entry(150, 3, 3, 1)]
+        result = find_tile(entries, 51)
+        self.assertEqual(result.offset, 1)
+        self.assertEqual(result.length, 1)
+
+    def test_find_tile_leaf(self):
+        entries = [Entry(100, 1, 1, 0)]
+        result = find_tile(entries, 150)
+        self.assertEqual(result.offset, 1)
+        self.assertEqual(result.length, 1)