From 3ddbaf955e45eed15662e2f141b75dc0df63c1b0 Mon Sep 17 00:00:00 2001 From: Prem Sichanugrist Date: Sun, 21 Nov 2010 01:36:27 +0700 Subject: [PATCH 1/3] Mention the case that `render` will return nil if given `:collection` is nil or empty when rendering partial. --- actionpack/lib/action_view/partials.rb | 5 +++++ 1 file changed, 5 insertions(+) diff --git a/actionpack/lib/action_view/partials.rb b/actionpack/lib/action_view/partials.rb index 844c3e9572..cd3f130dc4 100644 --- a/actionpack/lib/action_view/partials.rb +++ b/actionpack/lib/action_view/partials.rb @@ -75,6 +75,11 @@ module ActionView # # <%= render :partial => "ad", :collection => @advertisements, :spacer_template => "ad_divider" %> # + # If the given :collection is nil or empty, render will return nil. This will allow you + # to specify a text which will displayed instead by using this form: + # + # <%= render(:partial => "ad", :collection => @advertisements) || "There's no ad to be displayed" %> + # # NOTE: Due to backwards compatibility concerns, the collection can't be one of hashes. Normally you'd also # just keep domain objects, like Active Records, in there. # From d773ef8e8c819f09ad3b436b11631c26e4ca2ff9 Mon Sep 17 00:00:00 2001 From: Jamison Dance Date: Sat, 20 Nov 2010 14:55:39 -0700 Subject: [PATCH 2/3] fix some grammar issues with section 2.5 --- .../guides/source/active_record_validations_callbacks.textile | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) diff --git a/railties/guides/source/active_record_validations_callbacks.textile b/railties/guides/source/active_record_validations_callbacks.textile index 444a1d4154..59db20c926 100644 --- a/railties/guides/source/active_record_validations_callbacks.textile +++ b/railties/guides/source/active_record_validations_callbacks.textile @@ -141,7 +141,7 @@ end h4(#validations_overview-errors). +errors[]+ -To verify whether or not a particular attribute of an object is valid, you can use +errors[:attribute]+ that returns an array with all attribute errors, when there are no errors on the specified attribute, an empty array is returned. +To verify whether or not a particular attribute of an object is valid, you can use +errors[:attribute]+. It returns an array of all the errors for +:attribue+. If there are no errors on the specified attribute, an empty array is returned. This method is only useful _after_ validations have been run, because it only inspects the errors collection and does not trigger validations itself. It's different from the +ActiveRecord::Base#invalid?+ method explained above because it doesn't verify the validity of the object as a whole. It only checks to see whether there are errors found on an individual attribute of the object. From 074782eda2caddb054d20a99e8d167ef8e1eecd2 Mon Sep 17 00:00:00 2001 From: Xavier Noria Date: Sun, 21 Nov 2010 00:01:10 +0100 Subject: [PATCH 3/3] copy-edits d773ef8 --- .../guides/source/active_record_validations_callbacks.textile | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) diff --git a/railties/guides/source/active_record_validations_callbacks.textile b/railties/guides/source/active_record_validations_callbacks.textile index 59db20c926..9ddbe6fadc 100644 --- a/railties/guides/source/active_record_validations_callbacks.textile +++ b/railties/guides/source/active_record_validations_callbacks.textile @@ -141,7 +141,7 @@ end h4(#validations_overview-errors). +errors[]+ -To verify whether or not a particular attribute of an object is valid, you can use +errors[:attribute]+. It returns an array of all the errors for +:attribue+. If there are no errors on the specified attribute, an empty array is returned. +To verify whether or not a particular attribute of an object is valid, you can use +errors[:attribute]+. It returns an array of all the errors for +:attribute+. If there are no errors on the specified attribute, an empty array is returned. This method is only useful _after_ validations have been run, because it only inspects the errors collection and does not trigger validations itself. It's different from the +ActiveRecord::Base#invalid?+ method explained above because it doesn't verify the validity of the object as a whole. It only checks to see whether there are errors found on an individual attribute of the object.