Lawrence Song! Agile, Ruby, Java, C# and Javascript

The current will_paginate plugin doesn’t support localization. Adding the following code into the application_helper will enable i18n for will_paginate.

include WillPaginate::ViewHelpers 

def will_paginate_with_i18n(collection, options = {}) 
  will_paginate_without_i18n(collection, options.merge(:previous_label => I18n.t(:previous), :next_label => I18n.t(:next))) 
end 

alias_method_chain :will_paginate, :i18n 

And add ‘next’ and ‘previous’ attribute in the locales file.

for example zh.yml under RAILS_ROOT/config/locales

zh: 
  previous: '前一页' 
  next: '下一页' 

Enable i18n in will_paginate Plugin

ORDER BY items must appear in the select list if SELECT DISTINCT is specified.

Add the following code at the end of method add_limit_offset!(sql, options) in sqlserver_adapter.rb

if options[:order]
  order_fields = options[:order].split(',').collect do |field|
    column_name = field.split(" ")[0]
    "#{column_name} AS #{column_name.gsub('.', '_')}"
  end
  sql.gsub!(/^\s*SELECT(\s+DISTINCT)(.*?) FROM/i, "SELECT\\1 \\2, #{order_fields.join(', ')} FROM")
end

activerecord sqlserver_adapter bug

In rspec, I usually need to define a matcher to match arguments. I don’t want to create a match for every should_receive method. I just want to assert the arguments I care. I try to define a code block to assert my call arguments. I google it for a while and could not find an answer.

I want to do something like:

User.should_receive(:find).with(assert_that(lambda { |args
  options = args.pop
  options[:include].should == expected_include
  options[:limit].should == 100
}).and_return(:users)

After reading rspec source code, I finger out rspec should_receive argument allow code block. That’s easier than what I expect. The finial code is:

User.should_receive(:find).with do |*args|
  options = args.pop
  options[:include].should == expected_include
  options[:limit].should == 100
  true
end.and_return(:users)

remember to return true at the end if all assertions pass.

rspec - match arguments with code block

I18n label is still not supported in rails 2.3.2. Here is the patch to make it work. However, I don’t want to change the source code of rails. Hence, I create a monkey patch.

module ActionView
  module Helpers
    class InstanceTag
      def to_label_tag_with_i18n(text = nil, options = {})
        text ||= object.class.human_attribute_name(method_name) if object.class.respond_to?(:human_attribute_name)

        to_label_tag_without_i18n(text, options)
      end

      alias_method_chain :to_label_tag, :i18n
    end
  end
end

Load the file in the environment.rb or any file in confit/initializers will make it work.

i18n label in rails (monkey patch)

SEO has become a hot topic in the Internet. I am working in my personal project which I’d like to have a friendly URL. I need to create a slug as my friend URL. But, the slug is case sensitive in my case. for example, word ‘fisher’ is different to name ‘Fisher’ in a dictionary. unfortunately, MySQL is case sensitive by default. So I need to change the setting for the slug field in my table.

I change my slug field in MySQL by adding the following code into my migration script:

execute %{ALTER TABLE TABLE_NAME MODIFY slug varchar(255) COLLATE utf8_bin NOT NULL} 

That works fine in my production database which is MySQL. However, I am using sqlite3 in test which is case sensitive by default. So I need to modify the field only in MySQL database. The finial code I put in my migration script is following:

if ActiveRecord::Base.configurations[RAILS_ENV]['adapter'] == 'mysql' 
  execute %{ALTER TABLE words MODIFY slug varchar(255) COLLATE utf8_bin NOT NULL} 
end 

COLLATE options in MySQL:

• utf8_bin: compare strings by the binary value of each character
• utf8_general_ci: compare strings using general language rules, case insensitive
• utf8_general_cs: compare strings using general language case sensitive

Enable Case Sensitive Field in Mysql in Ruby on Rails