Fix %Y date format %Y

lib/timecop/time_extensions.rb

@@ -50,11 +50,16 @@ def strptime_with_mock_date(str = '-4712-01-01', fmt = '%F', start = Date::ITALY
           "supports Date::ITALY for the start argument."
       end
 
-      d = Date._strptime(str, fmt) || Date.strptime_without_mock_date(str, fmt)
+      #If date is not valid the following line raises
+      Date.strptime_without_mock_date(str, fmt)
+
+      d = Date._strptime(str, fmt)
       now = Time.now.to_date
       year = d[:year] || now.year
       mon = d[:mon] || now.mon
-      if d[:mday]
+      if d.keys == [:year]
+        Date.new(year)
+      elsif d[:mday]
         Date.new(year, mon, d[:mday])
       elsif d[:wday]
         Date.new(year, mon, now.mday) + (d[:wday] - now.wday)

test/date_strptime_scenarios.rb

@@ -1,6 +1,11 @@
 module DateStrptimeScenarios
 
   #calling freeze and travel tests are making the date Time.local(1984,2,28)
+
+  def test_date_strptime_with_year
+    assert_equal Date.strptime('1999', '%Y'), Date.new(1999, 1, 1)
+  end
+
   def test_date_strptime_without_year
     assert_equal Date.strptime('04-14', '%m-%d'), Date.new(1984, 4, 14)
   end