Fix regression bug that made date_select and datetime_select raise a Null Pointer Exception when a nil date/datetime was passed and only month and year were displayed [#1289 state:committed]

Signed-off-by: David Heinemeier Hansson <david@loudthinking.com>

actionpack/CHANGELOG

@@ -1,5 +1,7 @@
 *2.2.1 [RC2 or 2.2 final]*
 
+* Fix regression bug that made date_select and datetime_select raise a Null Pointer Exception when a nil date/datetime was passed and only month and year were displayed #1289 [Bernardo Padua/Tor Erik]
+
 * Simplified the logging format for parameters (don't include controller, action, and format as duplicates) [DHH]
 
 * Remove the logging of the Session ID when the session store is CookieStore [DHH]

actionpack/lib/action_view/helpers/date_helper.rb

@@ -539,7 +539,7 @@ module ActionView
 
           # If the day is hidden and the month is visible, the day should be set to the 1st so all month choices are
           # valid (otherwise it could be 31 and february wouldn't be a valid date)
-          if @options[:discard_day] && !@options[:discard_month]
+          if @datetime && @options[:discard_day] && !@options[:discard_month]
             @datetime = @datetime.change(:day => 1)
           end
 
@@ -567,7 +567,7 @@ module ActionView
 
           # If the day is hidden and the month is visible, the day should be set to the 1st so all month choices are
           # valid (otherwise it could be 31 and february wouldn't be a valid date)
-          if @options[:discard_day] && !@options[:discard_month]
+          if @datetime && @options[:discard_day] && !@options[:discard_month]
             @datetime = @datetime.change(:day => 1)
           end
         end

actionpack/test/template/date_helper_test.rb

@@ -1149,6 +1149,46 @@ class DateHelperTest < ActionView::TestCase
 
     assert_dom_equal expected, date_select("post", "written_on", :include_blank => true)
   end
+  
+  def test_date_select_with_nil_and_blank_and_order
+    @post = Post.new
+
+    start_year = Time.now.year-5
+    end_year   = Time.now.year+5
+    
+    expected = '<input name="post[written_on(3i)]" type="hidden" id="post_written_on_3i"/>' + "\n"
+    expected <<   %{<select id="post_written_on_1i" name="post[written_on(1i)]">\n}
+    expected << "<option value=\"\"></option>\n"
+    start_year.upto(end_year) { |i| expected << %(<option value="#{i}">#{i}</option>\n) }
+    expected << "</select>\n"
+
+    expected << %{<select id="post_written_on_2i" name="post[written_on(2i)]">\n}
+    expected << "<option value=\"\"></option>\n"
+    1.upto(12) { |i| expected << %(<option value="#{i}">#{Date::MONTHNAMES[i]}</option>\n) }
+    expected << "</select>\n"
+
+    assert_dom_equal expected, date_select("post", "written_on", :order=>[:year, :month], :include_blank=>true)
+  end
+
+  def test_date_select_with_nil_and_blank_and_order
+    @post = Post.new
+
+    start_year = Time.now.year-5
+    end_year   = Time.now.year+5
+
+    expected = '<input name="post[written_on(3i)]" type="hidden" id="post_written_on_3i"/>' + "\n"
+    expected <<   %{<select id="post_written_on_1i" name="post[written_on(1i)]">\n}
+    expected << "<option value=\"\"></option>\n"
+    start_year.upto(end_year) { |i| expected << %(<option value="#{i}">#{i}</option>\n) }
+    expected << "</select>\n"
+
+    expected << %{<select id="post_written_on_2i" name="post[written_on(2i)]">\n}
+    expected << "<option value=\"\"></option>\n"
+    1.upto(12) { |i| expected << %(<option value="#{i}">#{Date::MONTHNAMES[i]}</option>\n) }
+    expected << "</select>\n"
+
+    assert_dom_equal expected, date_select("post", "written_on", :order=>[:year, :month], :include_blank=>true)
+  end
 
   def test_date_select_cant_override_discard_hour
     @post = Post.new