test processing_order()

diff --git a/tests/test_processing_order.py b/tests/test_processing_order.py
new file mode 100644 (file)
index 0000000..cc33fd4
--- /dev/null
+++ b/tests/test_processing_order.py
@@ -0,0 +1,113 @@
+
+import dns.rdata
+import dns.rdataset
+
+
+def test_processing_order_shuffle():
+    rds = dns.rdataset.from_text('in', 'a', 300,
+                                 '10.0.0.1', '10.0.0.2', '10.0.0.3')
+    seen = set()
+    for i in range(100):
+        po = rds.processing_order()
+        assert len(po) == 3
+        for j in range(3):
+            assert rds[j] in po
+        seen.add(tuple(po))
+    assert len(seen) == 6
+
+
+def test_processing_order_priority_mx():
+    rds = dns.rdataset.from_text('in', 'mx', 300,
+                                 '10 a', '20 b', '20 c')
+    seen = set()
+    for i in range(100):
+        po = rds.processing_order()
+        assert len(po) == 3
+        for j in range(3):
+            assert rds[j] in po
+        assert rds[0] == po[0]
+        seen.add(tuple(po))
+    assert len(seen) == 2
+
+
+def test_processing_order_priority_weighted():
+    rds = dns.rdataset.from_text('in', 'srv', 300,
+                                 '1 10 1234 a', '2 90 1234 b', '2 10 1234 c')
+    seen = set()
+    weight_90_count = 0
+    weight_10_count = 0
+    for i in range(100):
+        po = rds.processing_order()
+        assert len(po) == 3
+        for j in range(3):
+            assert rds[j] in po
+        assert rds[0] == po[0]
+        if po[1].weight == 90:
+            weight_90_count += 1
+        else:
+            assert po[1].weight == 10
+            weight_10_count += 1
+        seen.add(tuple(po))
+    assert len(seen) == 2
+    # We can't assert anything with certainty given these are random
+    # draws, but it's super likely that weight_90_count > weight_10_count,
+    # so we just assert that.
+    assert weight_90_count > weight_10_count
+
+
+def test_processing_order_priority_naptr():
+    rds = dns.rdataset.from_text('in', 'naptr', 300,
+                                 '1 10 a b c foo.', '1 20 a b c foo.',
+                                 '2 10 a b c foo.', '2 10 d e f bar.')
+    seen = set()
+    for i in range(100):
+        po = rds.processing_order()
+        assert len(po) == 4
+        for j in range(4):
+            assert rds[j] in po
+        assert rds[0] == po[0]
+        assert rds[1] == po[1]
+        seen.add(tuple(po))
+    assert len(seen) == 2
+
+
+def test_processing_order_empty():
+    rds = dns.rdataset.from_text('in', 'naptr', 300)
+    po = rds.processing_order()
+    assert po == []
+
+
+def test_processing_singleton_priority():
+    rds = dns.rdataset.from_text('in', 'mx', 300, '10 a')
+    po = rds.processing_order()
+    print(po)
+    assert po == [rds[0]]
+
+
+def test_processing_singleton_weighted():
+    rds = dns.rdataset.from_text('in', 'srv', 300, '1 10 1234 a')
+    po = rds.processing_order()
+    print(po)
+    assert po == [rds[0]]
+
+
+def test_processing_all_zero_weight_srv():
+    rds = dns.rdataset.from_text('in', 'srv', 300,
+                                 '1 0 1234 a', '1 0 1234 b', '1 0 1234 c')
+    seen = set()
+    for i in range(100):
+        po = rds.processing_order()
+        assert len(po) == 3
+        for j in range(3):
+            assert rds[j] in po
+        seen.add(tuple(po))
+    assert len(seen) == 6
+
+
+def test_processing_all_zero_weight_uri():
+    rds = dns.rdataset.from_text('in', 'uri', 300,
+                                 '10 0 "ftp://ftp1.example.com/public"',
+                                 '10 0 "ftp://ftp2.example.com/public"',
+                                 '10 0 "ftp://ftp3.example.com/public"')
+    po = rds.processing_order()
+    assert len(po) == 0