Bug #416 - Sorting by due date with dateformat MD wrong

- Fixed bug #416, which caused sorting on a date to fail if the year was not
  included in the dateformat (thanks to Michelle Crane).
- Added unit tests.

src/Date.cpp

@@ -86,7 +86,7 @@ Date::Date (const std::string& mdy, const std::string& format /* = "m/d/Y" */)
 {
   int month  = 0;
   int day    = 0;
-  int year   = 0;
+  int year   = -1;   // So we can check later.
   int hour   = 0;
   int minute = 0;
   int second = 0;
@@ -332,6 +332,14 @@ Date::Date (const std::string& mdy, const std::string& format /* = "m/d/Y" */)
     }
   }
 
+  // Default the year to the current year, for formats that lack Y/y.
+  if (year == -1)
+  {
+    time_t now = time (NULL);
+    struct tm* default_year = localtime (&now);
+    year = default_year->tm_year + 1900;
+  }
+
   if (i < mdy.length ())
     throw std::string ("\"") + mdy + "\" is not a valid date in " + format + " format.";