# HG changeset patch
# User Paul Boddie <paul@boddie.org.uk>
# Date 1515782117 -3600
# Node ID 857aae8d5942678c7e1d23645d7d86360b33029c
# Parent  8b0c1cf12f174101fd8a60c63f34aa867a13d3ee
Override frequency qualifiers incompatible with yearday selectors.
Added support for serialising selectors, producing RRULE-compatible output.

diff -r 8b0c1cf12f17 -r 857aae8d5942 tests/internal/qualifiers.py
--- a/tests/internal/qualifiers.py	Fri Jan 12 19:33:18 2018 +0100
+++ b/tests/internal/qualifiers.py	Fri Jan 12 19:35:17 2018 +0100
@@ -40,6 +40,14 @@
     show(csel)
     return s
 
+def show_result(tests):
+    result = True
+    for test, expected, obtained in tests:
+        result = result and test
+        print test, expected, obtained
+    print
+    return result
+
 def test1():
     qualifiers = [
         ("YEARLY", {"interval" : 1})
@@ -48,10 +56,9 @@
     s = select(dt, qualifiers)
 
     l = s.materialise(dt, (2003, 12, 24))
-    print len(l) == 7, 7, len(l)
-    print l[0] == (1997, 11, 2), (1997, 11, 2), l[0]
-    print l[-1] == (2003, 11, 2), (2003, 11, 2), l[-1]
-    print
+    return show_result([(len(l) == 7, 7, len(l)),
+                        (l[0] == (1997, 11, 2), (1997, 11, 2), l[0]),
+                        (l[-1] == (2003, 11, 2), (2003, 11, 2), l[-1])])
 
 def test2():
     qualifiers = [
@@ -65,10 +72,9 @@
     s = select(dt, qualifiers)
 
     l = s.materialise(dt, (2003, 12, 24, 0, 0, 0))
-    print len(l) == 34, 34, len(l)
-    print l[0] == (1997, 1, 5, 8, 30, 0), (1997, 1, 5, 8, 30, 0), l[0]
-    print l[-1] == (2003, 1, 26, 9, 30, 0), (2003, 1, 26, 9, 30, 0), l[-1]
-    print
+    return show_result([(len(l) == 34, 34, len(l)),
+                        (l[0] == (1997, 1, 5, 8, 30, 0), (1997, 1, 5, 8, 30, 0), l[0]),
+                        (l[-1] == (2003, 1, 26, 9, 30, 0), (2003, 1, 26, 9, 30, 0), l[-1])])
 
 def test3():
     qualifiers = [
@@ -79,10 +85,9 @@
     s = select(dt, qualifiers)
 
     l = s.materialise(dt, (1997, 12, 24))
-    print len(l) == 10, 10, len(l)
-    print l[0] == (1997, 9, 2, 9, 0, 0), (1997, 9, 2, 9, 0, 0), l[0]
-    print l[-1] == (1997, 9, 11, 9, 0, 0), (1997, 9, 11, 9, 0, 0), l[-1]
-    print
+    return show_result([(len(l) == 10, 10, len(l)),
+                        (l[0] == (1997, 9, 2, 9, 0, 0), (1997, 9, 2, 9, 0, 0), l[0]),
+                        (l[-1] == (1997, 9, 11, 9, 0, 0), (1997, 9, 11, 9, 0, 0), l[-1])])
 
 def test4():
     qualifiers = [
@@ -92,10 +97,9 @@
     s = select(dt, qualifiers)
 
     l = s.materialise(dt, (1997, 12, 24, 0, 0, 0))
-    print len(l) == 113, 113, len(l)
-    print l[0] == (1997, 9, 2, 9, 0, 0), (1997, 9, 2, 9, 0, 0), l[0]
-    print l[-1] == (1997, 12, 23, 9, 0, 0), (1997, 12, 23, 9, 0, 0), l[-1]
-    print
+    return show_result([(len(l) == 113, 113, len(l)),
+                        (l[0] == (1997, 9, 2, 9, 0, 0), (1997, 9, 2, 9, 0, 0), l[0]),
+                        (l[-1] == (1997, 12, 23, 9, 0, 0), (1997, 12, 23, 9, 0, 0), l[-1])])
 
 def test5():
     qualifiers = get_qualifiers(["FREQ=DAILY", "UNTIL=19971224T000000Z"])
@@ -103,10 +107,9 @@
     s = select(dt, qualifiers)
 
     l = s.materialise(dt, (1997, 12, 25, 0, 0, 0), True)
-    print len(l) == 113, 113, len(l)
-    print l[0] == (1997, 9, 2, 9, 0, 0), (1997, 9, 2, 9, 0, 0), l[0]
-    print l[-1] == (1997, 12, 23, 9, 0, 0), (1997, 12, 23, 9, 0, 0), l[-1]
-    print
+    return show_result([(len(l) == 113, 113, len(l)),
+                        (l[0] == (1997, 9, 2, 9, 0, 0), (1997, 9, 2, 9, 0, 0), l[0]),
+                        (l[-1] == (1997, 12, 23, 9, 0, 0), (1997, 12, 23, 9, 0, 0), l[-1])])
 
     # See also test43.
 
@@ -118,10 +121,9 @@
     s = select(dt, qualifiers)
 
     l = s.materialise(dt, (1997, 12, 24, 0, 0, 0))
-    print len(l) == 57, 57, len(l)
-    print l[0] == (1997, 9, 2, 9, 0, 0), (1997, 9, 2, 9, 0, 0), l[0]
-    print l[-1] == (1997, 12, 23, 9, 0, 0), (1997, 12, 23, 9, 0, 0), l[-1]
-    print
+    return show_result([(len(l) == 57, 57, len(l)),
+                        (l[0] == (1997, 9, 2, 9, 0, 0), (1997, 9, 2, 9, 0, 0), l[0]),
+                        (l[-1] == (1997, 12, 23, 9, 0, 0), (1997, 12, 23, 9, 0, 0), l[-1])])
 
 def test7():
     qualifiers = [
@@ -131,10 +133,9 @@
     s = select(dt, qualifiers)
 
     l = s.materialise(dt, (1997, 12, 24, 0, 0, 0))
-    print len(l) == 17, 17, len(l)
-    print l[0] == (1997, 9, 2, 9, 0, 0), (1997, 9, 2, 9, 0, 0), l[0]
-    print l[-1] == (1997, 12, 23, 9, 0, 0), (1997, 12, 23, 9, 0, 0), l[-1]
-    print
+    return show_result([(len(l) == 17, 17, len(l)),
+                        (l[0] == (1997, 9, 2, 9, 0, 0), (1997, 9, 2, 9, 0, 0), l[0]),
+                        (l[-1] == (1997, 12, 23, 9, 0, 0), (1997, 12, 23, 9, 0, 0), l[-1])])
 
 def test8():
     qualifiers = [
@@ -145,10 +146,9 @@
     s = select(dt, qualifiers)
 
     l = s.materialise(dt, (1997, 12, 24, 0, 0, 0))
-    print len(l) == 5, 5, len(l)
-    print l[0] == (1997, 9, 2, 9, 0, 0), (1997, 9, 2, 9, 0, 0), l[0]
-    print l[-1] == (1997, 10, 12, 9, 0, 0), (1997, 10, 12, 9, 0, 0), l[-1]
-    print
+    return show_result([(len(l) == 5, 5, len(l)),
+                        (l[0] == (1997, 9, 2, 9, 0, 0), (1997, 9, 2, 9, 0, 0), l[0]),
+                        (l[-1] == (1997, 10, 12, 9, 0, 0), (1997, 10, 12, 9, 0, 0), l[-1])])
 
 def test9():
     qualifiers = [
@@ -160,10 +160,9 @@
     s = select(dt, qualifiers)
 
     l = s.materialise(dt, (2000, 1, 31, 14, 0, 0))
-    print len(l) == 93, 93, len(l)
-    print l[0] == (1998, 1, 1, 9, 0, 0), (1998, 1, 1, 9, 0, 0), l[0]
-    print l[-1] == (2000, 1, 31, 9, 0, 0), (2000, 1, 31, 9, 0, 0), l[-1]
-    print
+    return show_result([(len(l) == 93, 93, len(l)),
+                        (l[0] == (1998, 1, 1, 9, 0, 0), (1998, 1, 1, 9, 0, 0), l[0]),
+                        (l[-1] == (2000, 1, 31, 9, 0, 0), (2000, 1, 31, 9, 0, 0), l[-1])])
 
 def test10():
     qualifiers = [
@@ -174,10 +173,9 @@
     s = select(dt, qualifiers)
 
     l = s.materialise(dt, (2000, 1, 31, 14, 0, 0))
-    print len(l) == 93, 93, len(l)
-    print l[0] == (1998, 1, 1, 9, 0, 0), (1998, 1, 1, 9, 0, 0), l[0]
-    print l[-1] == (2000, 1, 31, 9, 0, 0), (2000, 1, 31, 9, 0, 0), l[-1]
-    print
+    return show_result([(len(l) == 93, 93, len(l)),
+                        (l[0] == (1998, 1, 1, 9, 0, 0), (1998, 1, 1, 9, 0, 0), l[0]),
+                        (l[-1] == (2000, 1, 31, 9, 0, 0), (2000, 1, 31, 9, 0, 0), l[-1])])
 
 def test11():
     qualifiers = [
@@ -188,10 +186,9 @@
     s = select(dt, qualifiers)
 
     l = s.materialise(dt, (1997, 12, 24, 0, 0, 0))
-    print len(l) == 10, 10, len(l)
-    print l[0] == (1997, 9, 2, 9, 0, 0), (1997, 9, 2, 9, 0, 0), l[0]
-    print l[-1] == (1997, 11, 4, 9, 0, 0), (1997, 11, 4, 9, 0, 0), l[-1]
-    print
+    return show_result([(len(l) == 10, 10, len(l)),
+                        (l[0] == (1997, 9, 2, 9, 0, 0), (1997, 9, 2, 9, 0, 0), l[0]),
+                        (l[-1] == (1997, 11, 4, 9, 0, 0), (1997, 11, 4, 9, 0, 0), l[-1])])
 
 def test12():
     qualifiers = [
@@ -201,10 +198,9 @@
     s = select(dt, qualifiers)
 
     l = s.materialise(dt, (1997, 12, 24, 0, 0, 0))
-    print len(l) == 17, 17, len(l)
-    print l[0] == (1997, 9, 2, 9, 0, 0), (1997, 9, 2, 9, 0, 0), l[0]
-    print l[-1] == (1997, 12, 23, 9, 0, 0), (1997, 12, 23, 9, 0, 0), l[-1]
-    print
+    return show_result([(len(l) == 17, 17, len(l)),
+                        (l[0] == (1997, 9, 2, 9, 0, 0), (1997, 9, 2, 9, 0, 0), l[0]),
+                        (l[-1] == (1997, 12, 23, 9, 0, 0), (1997, 12, 23, 9, 0, 0), l[-1])])
 
 def test13():
     qualifiers = [
@@ -214,10 +210,9 @@
     s = select(dt, qualifiers)
 
     l = s.materialise(dt, (1997, 12, 24, 0, 0, 0))
-    print len(l) == 17, 17, len(l)
-    print l[0] == (1997, 9, 2), (1997, 9, 2), l[0]
-    print l[-1] == (1997, 12, 23), (1997, 12, 23), l[-1]
-    print
+    return show_result([(len(l) == 17, 17, len(l)),
+                        (l[0] == (1997, 9, 2), (1997, 9, 2), l[0]),
+                        (l[-1] == (1997, 12, 23), (1997, 12, 23), l[-1])])
 
 def test14():
     qualifiers = [
@@ -227,10 +222,9 @@
     s = select(dt, qualifiers)
 
     l = s.materialise(dt, (1998, 2, 20, 0, 0, 0))
-    print len(l) == 13, 13, len(l)
-    print l[0] == (1997, 9, 2, 9, 0, 0), (1997, 9, 2, 9, 0, 0), l[0]
-    print l[-1] == (1998, 2, 17, 9, 0, 0), (1998, 2, 17, 9, 0, 0), l[-1]
-    print
+    return show_result([(len(l) == 13, 13, len(l)),
+                        (l[0] == (1997, 9, 2, 9, 0, 0), (1997, 9, 2, 9, 0, 0), l[0]),
+                        (l[-1] == (1998, 2, 17, 9, 0, 0), (1998, 2, 17, 9, 0, 0), l[-1])])
 
 def test15():
     qualifiers = [
@@ -241,10 +235,9 @@
     s = select(dt, qualifiers)
 
     l = s.materialise(dt, (1997, 10, 7, 9, 0, 0))
-    print len(l) == 10, 10, len(l)
-    print l[0] == (1997, 9, 2, 9, 0, 0), (1997, 9, 2, 9, 0, 0), l[0]
-    print l[-1] == (1997, 10, 2, 9, 0, 0), (1997, 10, 2, 9, 0, 0), l[-1]
-    print
+    return show_result([(len(l) == 10, 10, len(l)),
+                        (l[0] == (1997, 9, 2, 9, 0, 0), (1997, 9, 2, 9, 0, 0), l[0]),
+                        (l[-1] == (1997, 10, 2, 9, 0, 0), (1997, 10, 2, 9, 0, 0), l[-1])])
 
 def test16():
     qualifiers = [
@@ -256,10 +249,9 @@
     s = select(dt, qualifiers)
 
     l = s.materialise(dt, (1997, 12, 24, 0, 0, 0))
-    print len(l) == 10, 10, len(l)
-    print l[0] == (1997, 9, 2, 9, 0, 0), (1997, 9, 2, 9, 0, 0), l[0]
-    print l[-1] == (1997, 10, 2, 9, 0, 0), (1997, 10, 2, 9, 0, 0), l[-1]
-    print
+    return show_result([(len(l) == 10, 10, len(l)),
+                        (l[0] == (1997, 9, 2, 9, 0, 0), (1997, 9, 2, 9, 0, 0), l[0]),
+                        (l[-1] == (1997, 10, 2, 9, 0, 0), (1997, 10, 2, 9, 0, 0), l[-1])])
 
 def test17():
     qualifiers = [
@@ -270,10 +262,9 @@
     s = select(dt, qualifiers)
 
     l = s.materialise(dt, (1997, 12, 24, 0, 0, 0))
-    print len(l) == 25, 25, len(l)
-    print l[0] == (1997, 9, 1, 9, 0, 0), (1997, 9, 1, 9, 0, 0), l[0]
-    print l[-1] == (1997, 12, 22, 9, 0, 0), (1997, 12, 22, 9, 0, 0), l[-1]
-    print
+    return show_result([(len(l) == 25, 25, len(l)),
+                        (l[0] == (1997, 9, 1, 9, 0, 0), (1997, 9, 1, 9, 0, 0), l[0]),
+                        (l[-1] == (1997, 12, 22, 9, 0, 0), (1997, 12, 22, 9, 0, 0), l[-1])])
 
 def test18():
     qualifiers = [
@@ -285,10 +276,9 @@
     s = select(dt, qualifiers)
 
     l = s.materialise(dt, (1997, 12, 24, 0, 0, 0))
-    print len(l) == 8, 8, len(l)
-    print l[0] == (1997, 9, 2, 9, 0, 0), (1997, 9, 2, 9, 0, 0), l[0]
-    print l[-1] == (1997, 10, 16, 9, 0, 0), (1997, 10, 16, 9, 0, 0), l[-1]
-    print
+    return show_result([(len(l) == 8, 8, len(l)),
+                        (l[0] == (1997, 9, 2, 9, 0, 0), (1997, 9, 2, 9, 0, 0), l[0]),
+                        (l[-1] == (1997, 10, 16, 9, 0, 0), (1997, 10, 16, 9, 0, 0), l[-1])])
 
 def test19():
     qualifiers = [
@@ -300,10 +290,9 @@
     s = select(dt, qualifiers)
 
     l = s.materialise(dt, (1998, 12, 24, 0, 0, 0))
-    print len(l) == 10, 10, len(l)
-    print l[0] == (1997, 9, 5, 9, 0, 0), (1997, 9, 5, 9, 0, 0), l[0]
-    print l[-1] == (1998, 6, 5, 9, 0, 0), (1998, 6, 5, 9, 0, 0), l[-1]
-    print
+    return show_result([(len(l) == 10, 10, len(l)),
+                        (l[0] == (1997, 9, 5, 9, 0, 0), (1997, 9, 5, 9, 0, 0), l[0]),
+                        (l[-1] == (1998, 6, 5, 9, 0, 0), (1998, 6, 5, 9, 0, 0), l[-1])])
 
 def test20():
     qualifiers = [
@@ -314,10 +303,9 @@
     s = select(dt, qualifiers)
 
     l = s.materialise(dt, (1997, 12, 24, 0, 0, 0))
-    print len(l) == 4, 4, len(l)
-    print l[0] == (1997, 9, 5, 9, 0, 0), (1997, 9, 5, 9, 0, 0), l[0]
-    print l[-1] == (1997, 12, 5, 9, 0, 0), (1997, 12, 5, 9, 0, 0), l[-1]
-    print
+    return show_result([(len(l) == 4, 4, len(l)),
+                        (l[0] == (1997, 9, 5, 9, 0, 0), (1997, 9, 5, 9, 0, 0), l[0]),
+                        (l[-1] == (1997, 12, 5, 9, 0, 0), (1997, 12, 5, 9, 0, 0), l[-1])])
 
 def test21():
     qualifiers = [
@@ -329,10 +317,9 @@
     s = select(dt, qualifiers)
 
     l = s.materialise(dt, (1998, 12, 24, 0, 0, 0))
-    print len(l) == 10, 10, len(l)
-    print l[0] == (1997, 9, 7, 9, 0, 0), (1997, 9, 7, 9, 0, 0), l[0]
-    print l[-1] == (1998, 5, 31, 9, 0, 0), (1998, 5, 31, 9, 0, 0), l[-1]
-    print
+    return show_result([(len(l) == 10, 10, len(l)),
+                        (l[0] == (1997, 9, 7, 9, 0, 0), (1997, 9, 7, 9, 0, 0), l[0]),
+                        (l[-1] == (1998, 5, 31, 9, 0, 0), (1998, 5, 31, 9, 0, 0), l[-1])])
 
 def test22():
     qualifiers = [
@@ -344,10 +331,9 @@
     s = select(dt, qualifiers)
 
     l = s.materialise(dt, (1998, 12, 24, 0, 0, 0))
-    print len(l) == 6, 6, len(l)
-    print l[0] == (1997, 9, 22, 9, 0, 0), (1997, 9, 22, 9, 0, 0), l[0]
-    print l[-1] == (1998, 2, 16, 9, 0, 0), (1998, 2, 16, 9, 0, 0), l[-1]
-    print
+    return show_result([(len(l) == 6, 6, len(l)),
+                        (l[0] == (1997, 9, 22, 9, 0, 0), (1997, 9, 22, 9, 0, 0), l[0]),
+                        (l[-1] == (1998, 2, 16, 9, 0, 0), (1998, 2, 16, 9, 0, 0), l[-1])])
 
 def test23():
     qualifiers = [
@@ -359,10 +345,9 @@
     s = select(dt, qualifiers)
 
     l = s.materialise(dt, (1998, 12, 24, 0, 0, 0))
-    print len(l) == 6, 6, len(l)
-    print l[0] == (1997, 9, 28, 9, 0, 0), (1997, 9, 28, 9, 0, 0), l[0]
-    print l[-1] == (1998, 2, 26, 9, 0, 0), (1998, 2, 26, 9, 0, 0), l[-1]
-    print
+    return show_result([(len(l) == 6, 6, len(l)),
+                        (l[0] == (1997, 9, 28, 9, 0, 0), (1997, 9, 28, 9, 0, 0), l[0]),
+                        (l[-1] == (1998, 2, 26, 9, 0, 0), (1998, 2, 26, 9, 0, 0), l[-1])])
 
 def test24():
     qualifiers = [
@@ -374,10 +359,9 @@
     s = select(dt, qualifiers)
 
     l = s.materialise(dt, (1998, 12, 24, 0, 0, 0))
-    print len(l) == 10, 10, len(l)
-    print l[0] == (1997, 9, 2, 9, 0, 0), (1997, 9, 2, 9, 0, 0), l[0]
-    print l[-1] == (1998, 1, 15, 9, 0, 0), (1998, 1, 15, 9, 0, 0), l[-1]
-    print
+    return show_result([(len(l) == 10, 10, len(l)),
+                        (l[0] == (1997, 9, 2, 9, 0, 0), (1997, 9, 2, 9, 0, 0), l[0]),
+                        (l[-1] == (1998, 1, 15, 9, 0, 0), (1998, 1, 15, 9, 0, 0), l[-1])])
 
 def test25():
     qualifiers = [
@@ -389,10 +373,9 @@
     s = select(dt, qualifiers)
 
     l = s.materialise(dt, (1998, 12, 24, 0, 0, 0))
-    print len(l) == 10, 10, len(l)
-    print l[0] == (1997, 9, 30, 9, 0, 0), (1997, 9, 30, 9, 0, 0), l[0]
-    print l[-1] == (1998, 2, 1, 9, 0, 0), (1998, 2, 1, 9, 0, 0), l[-1]
-    print
+    return show_result([(len(l) == 10, 10, len(l)),
+                        (l[0] == (1997, 9, 30, 9, 0, 0), (1997, 9, 30, 9, 0, 0), l[0]),
+                        (l[-1] == (1998, 2, 1, 9, 0, 0), (1998, 2, 1, 9, 0, 0), l[-1])])
 
 def test26():
     qualifiers = [
@@ -404,10 +387,9 @@
     s = select(dt, qualifiers)
 
     l = s.materialise(dt, (1999, 12, 24, 0, 0, 0))
-    print len(l) == 10, 10, len(l)
-    print l[0] == (1997, 9, 10, 9, 0, 0), (1997, 9, 10, 9, 0, 0), l[0]
-    print l[-1] == (1999, 3, 13, 9, 0, 0), (1999, 3, 13, 9, 0, 0), l[-1]
-    print
+    return show_result([(len(l) == 10, 10, len(l)),
+                        (l[0] == (1997, 9, 10, 9, 0, 0), (1997, 9, 10, 9, 0, 0), l[0]),
+                        (l[-1] == (1999, 3, 13, 9, 0, 0), (1999, 3, 13, 9, 0, 0), l[-1])])
 
 def test27():
     qualifiers = [
@@ -418,10 +400,9 @@
     s = select(dt, qualifiers)
 
     l = s.materialise(dt, (1998, 4, 1, 0, 0, 0))
-    print len(l) == 18, 18, len(l)
-    print l[0] == (1997, 9, 2, 9, 0, 0), (1997, 9, 2, 9, 0, 0), l[0]
-    print l[-1] == (1998, 3, 31, 9, 0, 0), (1998, 3, 31, 9, 0, 0), l[-1]
-    print
+    return show_result([(len(l) == 18, 18, len(l)),
+                        (l[0] == (1997, 9, 2, 9, 0, 0), (1997, 9, 2, 9, 0, 0), l[0]),
+                        (l[-1] == (1998, 3, 31, 9, 0, 0), (1998, 3, 31, 9, 0, 0), l[-1])])
 
 def test28():
     qualifiers = [
@@ -433,10 +414,9 @@
     s = select(dt, qualifiers)
 
     l = s.materialise(dt, (2001, 12, 24, 0, 0, 0))
-    print len(l) == 10, 10, len(l)
-    print l[0] == (1997, 6, 10, 9, 0, 0), (1997, 6, 10, 9, 0, 0), l[0]
-    print l[-1] == (2001, 7, 10, 9, 0, 0), (2001, 7, 10, 9, 0, 0), l[-1]
-    print
+    return show_result([(len(l) == 10, 10, len(l)),
+                        (l[0] == (1997, 6, 10, 9, 0, 0), (1997, 6, 10, 9, 0, 0), l[0]),
+                        (l[-1] == (2001, 7, 10, 9, 0, 0), (2001, 7, 10, 9, 0, 0), l[-1])])
 
 def test29():
     qualifiers = [
@@ -448,10 +428,9 @@
     s = select(dt, qualifiers)
 
     l = s.materialise(dt, (2003, 12, 24, 0, 0, 0))
-    print len(l) == 10, 10, len(l)
-    print l[0] == (1997, 3, 10, 9, 0, 0), (1997, 3, 10, 9, 0, 0), l[0]
-    print l[-1] == (2003, 3, 10, 9, 0, 0), (2003, 3, 10, 9, 0, 0), l[-1]
-    print
+    return show_result([(len(l) == 10, 10, len(l)),
+                        (l[0] == (1997, 3, 10, 9, 0, 0), (1997, 3, 10, 9, 0, 0), l[0]),
+                        (l[-1] == (2003, 3, 10, 9, 0, 0), (2003, 3, 10, 9, 0, 0), l[-1])])
 
 def test30():
     qualifiers = [
@@ -463,10 +442,9 @@
     s = select(dt, qualifiers)
 
     l = s.materialise(dt, (2006, 2, 1, 0, 0, 0))
-    print len(l) == 10, 10, len(l)
-    print l[0] == (1997, 1, 1, 9, 0, 0), (1997, 1, 1, 9, 0, 0), l[0]
-    print l[-1] == (2006, 1, 1, 9, 0, 0), (2006, 1, 1, 9, 0, 0), l[-1]
-    print
+    return show_result([(len(l) == 10, 10, len(l)),
+                        (l[0] == (1997, 1, 1, 9, 0, 0), (1997, 1, 1, 9, 0, 0), l[0]),
+                        (l[-1] == (2006, 1, 1, 9, 0, 0), (2006, 1, 1, 9, 0, 0), l[-1])])
 
 def test31():
     qualifiers = [
@@ -477,10 +455,9 @@
     s = select(dt, qualifiers)
 
     l = s.materialise(dt, (1999, 12, 24, 0, 0, 0))
-    print len(l) == 3, 3, len(l)
-    print l[0] == (1997, 5, 19, 9, 0, 0), (1997, 5, 19, 9, 0, 0), l[0]
-    print l[-1] == (1999, 5, 17, 9, 0, 0), (1999, 5, 17, 9, 0, 0), l[-1]
-    print
+    return show_result([(len(l) == 3, 3, len(l)),
+                        (l[0] == (1997, 5, 19, 9, 0, 0), (1997, 5, 19, 9, 0, 0), l[0]),
+                        (l[-1] == (1999, 5, 17, 9, 0, 0), (1999, 5, 17, 9, 0, 0), l[-1])])
 
 def test32():
     qualifiers = [
@@ -493,10 +470,9 @@
 
 """
     l = s.materialise(dt, (1999, 12, 24, 0, 0, 0))
-    print len(l) == 3, 3, len(l)
-    print l[0] == (1997, 5, 12, 9, 0, 0), (1997, 5, 12, 9, 0, 0), l[0]
-    print l[-1] == (1999, 5, 17, 9, 0, 0), (1999, 5, 17, 9, 0, 0), l[-1]
-    print
+    return show_result([(len(l) == 3, 3, len(l)),
+                        (l[0] == (1997, 5, 12, 9, 0, 0), (1997, 5, 12, 9, 0, 0), l[0]),
+                        (l[-1] == (1999, 5, 17, 9, 0, 0), (1999, 5, 17, 9, 0, 0), l[-1])])
 """
 
 def test33():
@@ -509,10 +485,9 @@
     s = select(dt, qualifiers)
 
     l = s.materialise(dt, (1999, 12, 24, 0, 0, 0))
-    print len(l) == 11, 11, len(l)
-    print l[0] == (1997, 3, 13, 9, 0, 0), (1997, 3, 13, 9, 0, 0), l[0]
-    print l[-1] == (1999, 3, 25, 9, 0, 0), (1999, 3, 25, 9, 0, 0), l[-1]
-    print
+    return show_result([(len(l) == 11, 11, len(l)),
+                        (l[0] == (1997, 3, 13, 9, 0, 0), (1997, 3, 13, 9, 0, 0), l[0]),
+                        (l[-1] == (1999, 3, 25, 9, 0, 0), (1999, 3, 25, 9, 0, 0), l[-1])])
 
 def test34():
     qualifiers = [
@@ -524,10 +499,9 @@
     s = select(dt, qualifiers)
 
     l = s.materialise(dt, (1999, 12, 24, 0, 0, 0))
-    print len(l) == 39, 39, len(l)
-    print l[0] == (1997, 6, 5, 9, 0, 0), (1997, 6, 5, 9, 0, 0), l[0]
-    print l[-1] == (1999, 8, 26, 9, 0, 0), (1999, 8, 26, 9, 0, 0), l[-1]
-    print
+    return show_result([(len(l) == 39, 39, len(l)),
+                        (l[0] == (1997, 6, 5, 9, 0, 0), (1997, 6, 5, 9, 0, 0), l[0]),
+                        (l[-1] == (1999, 8, 26, 9, 0, 0), (1999, 8, 26, 9, 0, 0), l[-1])])
 
 def test35():
     qualifiers = [
@@ -539,10 +513,9 @@
     s = select(dt, qualifiers)
 
     l = s.materialise(dt, (2000, 12, 24, 0, 0, 0))
-    print len(l) == 6, 6, len(l)
-    print l[1] == (1998, 2, 13, 9, 0, 0), (1998, 2, 13, 9, 0, 0), l[1]
-    print l[-1] == (2000, 10, 13, 9, 0, 0), (2000, 10, 13, 9, 0, 0), l[-1]
-    print
+    return show_result([(len(l) == 6, 6, len(l)),
+                        (l[1] == (1998, 2, 13, 9, 0, 0), (1998, 2, 13, 9, 0, 0), l[1]),
+                        (l[-1] == (2000, 10, 13, 9, 0, 0), (2000, 10, 13, 9, 0, 0), l[-1])])
 
 def test36():
     qualifiers = [
@@ -554,10 +527,9 @@
     s = select(dt, qualifiers)
 
     l = s.materialise(dt, (1998, 6, 30, 0, 0, 0))
-    print len(l) == 10, 10, len(l)
-    print l[0] == (1997, 9, 13, 9, 0, 0), (1997, 9, 13, 9, 0, 0), l[0]
-    print l[-1] == (1998, 6, 13, 9, 0, 0), (1998, 6, 13, 9, 0, 0), l[-1]
-    print
+    return show_result([(len(l) == 10, 10, len(l)),
+                        (l[0] == (1997, 9, 13, 9, 0, 0), (1997, 9, 13, 9, 0, 0), l[0]),
+                        (l[-1] == (1998, 6, 13, 9, 0, 0), (1998, 6, 13, 9, 0, 0), l[-1])])
 
 def test37():
     qualifiers = [
@@ -570,10 +542,9 @@
     s = select(dt, qualifiers)
 
     l = s.materialise(dt, (2004, 12, 24, 0, 0, 0))
-    print len(l) == 3, 3, len(l)
-    print l[0] == (1996, 11, 5, 9, 0, 0), (1996, 11, 5, 9, 0, 0), l[0]
-    print l[-1] == (2004, 11, 2, 9, 0, 0), (2004, 11, 2, 9, 0, 0), l[-1]
-    print
+    return show_result([(len(l) == 3, 3, len(l)),
+                        (l[0] == (1996, 11, 5, 9, 0, 0), (1996, 11, 5, 9, 0, 0), l[0]),
+                        (l[-1] == (2004, 11, 2, 9, 0, 0), (2004, 11, 2, 9, 0, 0), l[-1])])
 
 def test38():
     qualifiers = [
@@ -586,10 +557,9 @@
     s = select(dt, qualifiers)
 
     l = s.materialise(dt, (1997, 12, 24, 0, 0, 0))
-    print len(l) == 3, 3, len(l)
-    print l[0] == (1997, 9, 4, 9, 0, 0), (1997, 9, 4, 9, 0, 0), l[0]
-    print l[-1] == (1997, 11, 6, 9, 0, 0), (1997, 11, 6, 9, 0, 0), l[-1]
-    print
+    return show_result([(len(l) == 3, 3, len(l)),
+                        (l[0] == (1997, 9, 4, 9, 0, 0), (1997, 9, 4, 9, 0, 0), l[0]),
+                        (l[-1] == (1997, 11, 6, 9, 0, 0), (1997, 11, 6, 9, 0, 0), l[-1])])
 
 def test39():
     qualifiers = [
@@ -601,10 +571,9 @@
     s = select(dt, qualifiers)
 
     l = s.materialise(dt, (1998, 4, 1, 0, 0, 0))
-    print len(l) == 7, 7, len(l)
-    print l[0] == (1997, 9, 29, 9, 0, 0), (1997, 9, 29, 9, 0, 0), l[0]
-    print l[-1] == (1998, 3, 30, 9, 0, 0), (1998, 3, 30, 9, 0, 0), l[-1]
-    print
+    return show_result([(len(l) == 7, 7, len(l)),
+                        (l[0] == (1997, 9, 29, 9, 0, 0), (1997, 9, 29, 9, 0, 0), l[0]),
+                        (l[-1] == (1998, 3, 30, 9, 0, 0), (1998, 3, 30, 9, 0, 0), l[-1])])
 
 def test40():
     qualifiers = get_qualifiers(["BYMONTHDAY=5", "FREQ=HOURLY", "INTERVAL=12"])
@@ -612,10 +581,9 @@
     s = select(dt, qualifiers)
 
     l = s.materialise(dt, (2019, 1, 1))
-    print len(l) == 37, 37, len(l)
-    print l[1] == (2017, 7, 5, 0), (2017, 7, 5, 0), l[1]
-    print l[-1] == (2018, 12, 5, 12), (2018, 12, 5, 12), l[-1]
-    print
+    return show_result([(len(l) == 37, 37, len(l)),
+                        (l[1] == (2017, 7, 5, 0), (2017, 7, 5, 0), l[1]),
+                        (l[-1] == (2018, 12, 5, 12), (2018, 12, 5, 12), l[-1])])
 
 def test41():
     qualifiers = get_qualifiers(["FREQ=DAILY", "BYMONTH=1"])
@@ -623,10 +591,9 @@
     s = select(dt, qualifiers)
 
     l = s.materialise(dt, (2019, 1, 1))
-    print len(l) == 32, 32, len(l)
-    print l[1] == (2018, 1, 1), (2018, 1, 1), l[1]
-    print l[-1] == (2018, 1, 31), (2018, 1, 31), l[-1]
-    print
+    return show_result([(len(l) == 32, 32, len(l)),
+                        (l[1] == (2018, 1, 1), (2018, 1, 1), l[1]),
+                        (l[-1] == (2018, 1, 31), (2018, 1, 31), l[-1])])
 
 def test42():
     qualifiers = get_qualifiers(["FREQ=MONTHLY", "BYDAY=WE,1FR,2MO,2FR"])
@@ -634,10 +601,9 @@
     s = select(dt, qualifiers)
 
     l = s.materialise(dt, (2018, 1, 1))
-    print len(l) == 18, 18, len(l)
-    print l[1] == (2017, 10, 18), (2017, 10, 18), l[1]
-    print l[-1] == (2017, 12, 27), (2017, 12, 27), l[-1]
-    print
+    return show_result([(len(l) == 18, 18, len(l)),
+                        (l[1] == (2017, 10, 18), (2017, 10, 18), l[1]),
+                        (l[-1] == (2017, 12, 27), (2017, 12, 27), l[-1])])
 
 def test43():
     qualifiers = get_qualifiers(["FREQ=DAILY", "UNTIL=19971224T090000Z"])
@@ -645,13 +611,36 @@
     s = select(dt, qualifiers)
 
     l = s.materialise(dt, (1997, 12, 25, 0, 0, 0), True)
-    print len(l) == 114, 114, len(l)
-    print l[0] == (1997, 9, 2, 9, 0, 0), (1997, 9, 2, 9, 0, 0), l[0]
-    print l[-1] == (1997, 12, 24, 9, 0, 0), (1997, 12, 24, 9, 0, 0), l[-1]
-    print
+    return show_result([(len(l) == 114, 114, len(l)),
+                        (l[0] == (1997, 9, 2, 9, 0, 0), (1997, 9, 2, 9, 0, 0), l[0]),
+                        (l[-1] == (1997, 12, 24, 9, 0, 0), (1997, 12, 24, 9, 0, 0), l[-1])])
 
     # See also test5.
 
+def test44():
+    qualifiers = get_qualifiers(["FREQ=MONTHLY", "BYDAY=WE,1FR,2MO,2FR"])
+    dt = (2017, 10, 15, 9, 30, 0)
+    s = select(dt, qualifiers)
+
+    l = s.materialise(dt, (2018, 1, 1))
+    return show_result([(len(l) == 18, 18, len(l)),
+                        (l[1] == (2017, 10, 18, 9, 30, 0), (2017, 10, 18, 9, 30, 0), l[1]),
+                        (l[-1] == (2017, 12, 27, 9, 30, 0), (2017, 12, 27, 9, 30, 0), l[-1])])
+
+    # See also test42.
+
+def test45():
+    qualifiers = get_qualifiers(["BYYEARDAY=1,100,200", "COUNT=10"])
+    dt = (1997, 1, 1, 9, 0, 0)
+    s = select(dt, qualifiers)
+
+    l = s.materialise(dt, (2006, 2, 1, 0, 0, 0))
+    return show_result([(len(l) == 10, 10, len(l)),
+                        (l[0] == (1997, 1, 1, 9, 0, 0), (1997, 1, 1, 9, 0, 0), l[0]),
+                        (l[-1] == (2006, 1, 1, 9, 0, 0), (2006, 1, 1, 9, 0, 0), l[-1])])
+
+    # See also test30.
+
 test0 = lambda: 0 # started at 1 above
 
 tests = [
@@ -659,7 +648,7 @@
     test10, test11, test12, test13, test14, test15, test16, test17, test18, test19,
     test20, test21, test22, test23, test24, test25, test26, test27, test28, test29,
     test30, test31, test32, test33, test34, test35, test36, test37, test38, test39,
-    test40, test41, test42, test43
+    test40, test41, test42, test43, test44, test45
 ]
 
 if __name__ == "__main__":
diff -r 8b0c1cf12f17 -r 857aae8d5942 vRecurrence.py
--- a/vRecurrence.py	Fri Jan 12 19:33:18 2018 +0100
+++ b/vRecurrence.py	Fri Jan 12 19:35:17 2018 +0100
@@ -165,6 +165,7 @@
 
     qualifiers = []
     frequency = None
+    have_yearday = False
     interval = 1
     keys = set()
 
@@ -198,6 +199,9 @@
         # Accept result set selection, truncation and enumerators as qualifiers.
 
         elif key in ("BYSETPOS", "COUNT") or enum.has_key(key):
+            if key == "BYYEARDAY":
+                have_yearday = True
+
             values = get_qualifier_values(key, value)
 
             # Ignore bad qualifier values.
@@ -213,21 +217,7 @@
 
         elif key == "UNTIL":
             try:
-                # YYYYMMDD
-
-                if len(value) == 8:
-                    end = map(int, (value[:4], value[4:6], value[6:]))
-
-                # YYYYMMDDTHHMMSS[Z]
-
-                elif len(value) in (15, 16):
-                    end = map(int, (value[:4], value[4:6], value[6:8], value[9:11], value[11:13], value[13:15]))
-
-                else:
-                    continue
-
-                qualifier = (key, {"end" : tuple(end)})
-
+                qualifier = (key, {"end" : string_to_tuple(value)})
             except ValueError:
                 continue
 
@@ -238,6 +228,13 @@
 
         qualifiers.append(qualifier)
 
+    # Forbid certain qualifiers with certain frequencies, coercing to
+    # appropriate frequencies.
+
+    if have_yearday and frequency and frequency[0] in ("WEEKLY", "DAILY"):
+        i = qualifiers.index(frequency)
+        del qualifiers[i]
+
     # Parameterise any frequency qualifier with the interval.
 
     if frequency:
@@ -588,7 +585,10 @@
 
     "Return whether 'from_sel' can be restricted using datetime information."
 
-    return not isinstance(from_sel, Pattern) and from_sel.qualifier != "BYDAY"
+    # Patterns are not restricted by higher-scale datetime information.
+    # BYDAY qualifiers are also not restricted by such information.
+
+    return not isinstance(from_sel, Pattern) and from_sel.qualifier not in ("BYDAY", "BYYEARDAY")
 
 def add_initial_selector(from_sel, level, l):
 
@@ -843,6 +843,33 @@
     else:
         return last_day - timedelta(last_weekday - weekday)
 
+def tuple_to_string(t):
+
+    "Return datetime or date tuple 't' as a string."
+
+    if len(t) >= 6:
+        return "%04d%02d%02dT%02d%02d%02d" % t
+    elif len(t) >= 3:
+        return "%04d%02d%02d" % t
+    else:
+        return None
+
+def string_to_tuple(s):
+
+    "Return 's' as a datetime or date tuple."
+
+    # YYYYMMDD
+
+    if len(s) == 8:
+        return tuple(map(int, (s[:4], s[4:6], s[6:])))
+
+    # YYYYMMDDTHHMMSS[Z]
+
+    elif len(s) in (15, 16):
+        return tuple(map(int, (s[:4], s[4:6], s[6:8], s[9:11], s[11:13], s[13:15])))
+
+    raise ValueError
+
 # Value expansion and sorting.
 
 def sort_values(values, limit=None):
@@ -1046,6 +1073,14 @@
     def as_tuple(self):
         return self.level, self.args, self.qualifier, self.selecting, self.first
 
+    # Serialisation support.
+
+    def to_property(self):
+        return ("FREQ=%s" % self.qualifier, "INTERVAL=%d" % self.get_interval())
+
+    def to_string(self):
+        return ";".join(self.to_property())
+
 class Enum(Selector):
 
     "A generic value selector."
@@ -1061,6 +1096,11 @@
     def get_values(self, limit=None):
         return sort_values(self.args["values"], limit)
 
+    # Serialisation support.
+
+    def to_property(self):
+        return ("%s=%s" % (self.qualifier, ",".join(map(str, self.get_values()))), )
+
 class WeekDayFilter(Enum):
 
     "A selector of instances specified in terms of day numbers."
@@ -1113,6 +1153,14 @@
             values.append(value)
         return values
 
+    # Serialisation support.
+
+    def to_property(self):
+        values = []
+        for (value, index) in self.get_values():
+            values.append("%d%s" % (index, weekday_values[value - 1]))
+        return ("%s=%s" % (self.qualifier, ",".join(values)), )
+
 class MonthDayFilter(Enum):
 
     "A selector of month days."
@@ -1145,6 +1193,11 @@
     def set_limit(self, limit):
         self.args["values"] = [limit]
 
+    # Serialisation support.
+
+    def to_property(self):
+        return ("%s=%d" % (self.qualifier, self.get_limit()), )
+
 class PositionSelector(Selector):
 
     "A result set position selector."
@@ -1170,6 +1223,11 @@
     def set_positions(self, positions):
         self.args["values"] = positions
 
+    # Serialisation support.
+
+    def to_property(self):
+        return ("%s=%s" % (self.qualifier, ",".join(self.get_positions())), )
+
 class StartSelector(Selector):
 
     "A selector ensuring that the start occurrence is included."
@@ -1181,6 +1239,11 @@
     def get_start(self):
         return self.args["start"]
 
+    # Serialisation support.
+
+    def to_property(self):
+        return ("%s=%s" % (self.qualifier, tuple_to_string(self.get_start())), )
+
 class UntilSelector(Selector):
 
     "A selector ensuring that the until datetime is not passed."
@@ -1192,6 +1255,11 @@
     def get_end(self):
         return self.args["end"]
 
+    # Serialisation support.
+
+    def to_property(self):
+        return ("%s=%s" % (self.qualifier, tuple_to_string(self.get_end())), )
+
 special_enum_levels = {
     "BYDAY" : WeekDayFilter,
     "BYMONTHDAY" : MonthDayFilter,
@@ -1666,4 +1734,24 @@
     else:
         return [selector]
 
+def to_property(selectors):
+
+    "Return a list of qualifier assignments for 'selectors'."
+
+    if isinstance(selectors, Selector):
+        selectors = get_selectors_from_selector(selectors)
+
+    t = ()
+
+    for selector in selectors:
+        t += selector.to_property()
+
+    return t
+
+def to_string(selectors):
+
+    "Return a string representation of 'selectors'."
+
+    return ";".join(to_property(selectors))
+
 # vim: tabstop=4 expandtab shiftwidth=4