datetime manipulation is now much clearer. tests were added, and expectations stated explicitly in many places. rules got lots of attention.

test/ezic_rule_tests.erl

@@ -0,0 +1,37 @@
+-module(ezic_rule_tests).
+-include("include/ezic.hrl").
+-include_lib("eunit/include/eunit.hrl").
+
+
+project_next_test_() ->
+    [
+     
+     % simple UTC example
+     ?_assertEqual({{2010,11,10},{16,20,0}}, 
+		   ezic_rule:project_next(
+		     #rule{from=1984, to=2032, in=11, on=10, at=#tztime{time={16,20,0}, flag=u}}
+		     , {-5,0,0}, {-1,0,0}, {{2010,11,10},{0,0,0}}
+		    ))
+
+     % skip a year UTC example
+     , ?_assertEqual({{2011,11,10},{16,20,0}}, 
+		   ezic_rule:project_next(
+		     #rule{from=1984, to=2032, in=11, on=10, at=#tztime{time={16,20,0}, flag=u}}
+		     , {-5,0,0}, {-1,0,0}, {{2010,11,10},{16,21,0}}
+		    ))
+
+     % skip 3 years UTC example
+     , ?_assertEqual({{2013,11,10},{16,20,0}}, 
+		   ezic_rule:project_next(
+		     #rule{from=1984, to=2032, in=11, on=10, at=#tztime{time={16,20,0}, flag=u}}
+		     , {-5,0,0}, {-1,0,0}, {{2012,11,11},{16,20,0}}
+		    ))
+
+     % no solution
+     , ?_assertEqual(none, 
+		   ezic_rule:project_next(
+		     #rule{from=1984, to=2010, in=11, on=10, at=#tztime{time={16,20,0}, flag=u}}
+		     , {-5,0,0}, {-1,0,0}, {{2012,11,11},{16,20,0}}
+		    ))
+
+    ].