Quick'n'dirty Jekyll plugin for sorted cycle

README.md

Jekyll sorted_for plugin

Quick'n'dirty Jekyll plugin for sorted cycle.

Install

Copy sorted_for.rb to _plugins/ directory of your Jekyll site.

Usage

Instead of for in templates use sorted_for. Add sort_by parameter with property you want to sort by, or leave it out if the array contains primitives (i.e. strings or numbers). Also supports reversed parameter as the original for tag.

{% sorted_for node in site.pages reversed sort_by:weight %}
  {{ node.title }}
{% endsorted_for %}

To use a custom sort property (eg. weight as in example above) add it to YAML Front Matter of your pages - see https://github.com/mojombo/jekyll/wiki/YAML-Front-Matter

String comparisons are case-insensitive by default, whether the collection contains strings or objects sorted by a string property. To enable case-sensitive string comparisons, apply the case_sensitive:true parameter.

To iterate over the keys in a hash, use sorted_keys_for.

{% sorted_keys_for tag in site.tags %}
  <a href="/tags/{{ tag | downcase | replace:" ","-"}}.html">{{ tag }}</a><br />
  Num posts: {{ site.tags[tag].size }}
{% endsorted_keys_for %}

Nested structures

To iterate over a nested array or hash, you will need to assign the inner collection to a variable before iterating over it using sorted_for or sorted_keys_for. This example assumes that the total number of posts per year and per month are stored in two separate (parallel) hashes, where page.month_totals is a hash-of-hashes:

<ul>
  {% sorted_keys_for year in page.year_totals reversed %}
  <li><a href="#{{ year }}">{{ year }}</a> - {{ page.year_totals[year] }} posts
    <ul>
      {% assign month_totals = page.month_totals[year] %}
      {% sorted_keys_for month in month_totals reversed %}
      <li><a href="#{{ year }}-{{month}}">{{ month | int_to_month_name }}</a>
          - {{ month_totals[month] }} posts</li>
      {% endsorted_keys_for %}
    </ul>
  </li>
  {% endsorted_keys_for %}
</ul>

This example assumes that the total number of posts per year and per month are stored in a single hash-of-hashes:

<ul>
  {% sorted_keys_for year in page.totals reversed %}
  {% assign totals = page.totals[year] %}
  <li><a href="#{{ year }}">{{ year }}</a> - {{ totals.year_total }} posts
    <ul>
      {% sorted_keys_for month in totals.month_totals reversed %}
      <li><a href="#{{year}}-{{month}}">{{ month | int_to_month_name }}</a>
          - {{ totals.month_totals[month] }} posts</li>
      {% endsorted_keys_for %}
    </ul>
  </li>
  {% endsorted_keys_for %}
</ul>

Rakefile

require 'rake'
require 'rake/testtask'

task :default => [:test]

Rake::TestTask.new(:test) do |test|
  test.libs << 'test'
  test.pattern = 'test/*_test.rb'
  test.verbose = true
end

sorted_for.rb

module Jekyll
  module SortedForImpl
    def render(context)
      sorted_collection = collection_to_sort context
      return if sorted_collection.empty?
      sort_attr = @attributes['sort_by']
      case_sensitive = @attributes['case_sensitive'] == 'true'
      i = sorted_collection.first

      if sort_attr != nil
        if i.to_liquid[sort_attr].instance_of? String and not case_sensitive
          sorted_collection.sort_by! { |i| i.to_liquid[sort_attr].downcase }
        else
          sorted_collection.sort_by! { |i| i.to_liquid[sort_attr] }
        end
      else
        if i.instance_of? String and not case_sensitive
          sorted_collection.sort_by! { |i| i.downcase }
        else
          sorted_collection.sort!
        end
      end

      original_name = @collection_name
      result = nil
      context.stack do
        sorted_collection_name = "#{@collection_name}_sorted".sub('.', '_')
        context[sorted_collection_name] = sorted_collection
        @collection_name = sorted_collection_name
        result = super
        @collection_name = original_name
      end
      result
    end
  end

  class SortedForTag < Liquid::For
    include SortedForImpl

    def collection_to_sort(context)
      return context[@collection_name].dup
    end

    def end_tag
      'endsorted_for'
    end
  end

  class SortedKeysForTag < Liquid::For
    include SortedForImpl

    def collection_to_sort(context)
      return context[@collection_name].keys
    end

    def end_tag
      'endsorted_keys_for'
    end
  end
end

Liquid::Template.register_tag('sorted_for', Jekyll::SortedForTag)
Liquid::Template.register_tag('sorted_keys_for', Jekyll::SortedKeysForTag)

sorted_for_test.rb

require 'liquid'
require 'test/unit'
require File.join(Gem.loaded_specs['liquid'].full_gem_path, 'test', 'test_helper.rb')
require File.join(File.dirname(__FILE__), '..', 'sorted_for.rb')

class SortedForTagAttributesTest < Test::Unit::TestCase
  include Liquid

  TEMPLATE = '{% sorted_for i in array sort_by:weight %}{{ i.name }}:{{ i.weight }} {% endsorted_for %}'
  REVERSED = '{% sorted_for i in array reversed sort_by:weight %}{{ i.name }}:{{ i.weight }} {% endsorted_for %}'

  def test_empty
    assert_template_result('', TEMPLATE, 'array' => [])
  end

  def test_single_element
    assert_template_result(
        'a:2 ',
        TEMPLATE,
        'array' => [{'name' => 'a', 'weight' => 2}])
  end

  def test_multiple_elements
    assert_template_result(
        'c:0 b:1 a:2 ',
        TEMPLATE,
        'array' => [
            {'name' => 'a', 'weight' => 2},
            {'name' => 'b', 'weight' => 1},
            {'name' => 'c', 'weight' => 0},
        ])
  end

  def test_reversed
    assert_template_result(
        'a:2 b:1 c:0 ',
        REVERSED,
        'array' => [
            {'name' => 'a', 'weight' => 2},
            {'name' => 'b', 'weight' => 1},
            {'name' => 'c', 'weight' => 0},
        ])
  end
end

class SortedForTagPrimitivesTest < Test::Unit::TestCase
  include Liquid

  TEMPLATE = '{% sorted_for i in array %}{{ i }} {% endsorted_for %}'
  REVERSED = '{% sorted_for i in array reversed %}{{ i }} {% endsorted_for %}'

  def test_empty
    assert_template_result('', TEMPLATE, 'array' => [])
  end

  def test_single_element
    assert_template_result('a ', TEMPLATE, 'array' => ['a'])
  end

  def test_multiple_elements
    assert_template_result('a b c ', TEMPLATE, 'array' => ['c', 'a', 'b'])
  end

  def test_reversed
    assert_template_result('c b a ', REVERSED, 'array' => ['c', 'a', 'b'])
  end
end

class SortedKeysForTagTest < Test::Unit::TestCase
  include Liquid

  TEMPLATE = '{% sorted_keys_for k in hash %}{{ k }}:{{ hash[k] }} {% endsorted_keys_for %}'
  REVERSED = '{% sorted_keys_for k in hash reversed %}{{ k }}:{{ hash[k] }} {% endsorted_keys_for %}'

  def test_empty
    assert_template_result('', TEMPLATE, 'hash' => {})
  end

  def test_single_element
    assert_template_result('a:0 ', TEMPLATE, 'hash' => {'a' => 0})
  end

  def test_multiple_elements
    assert_template_result('a:0 b:1 c:2 ', TEMPLATE, 'hash' => {'a' => 0, 'b' => 1, 'c' => 2})
  end

  def test_reversed
    assert_template_result('c:2 b:1 a:0 ', REVERSED, 'hash' => {'a' => 0, 'b' => 1, 'c' => 2})
  end
end

class SortedForTagCaseSensitivityTest < Test::Unit::TestCase
  include Liquid

  def test_default_is_case_insensitive
    assert_template_result(
      'alpha Beta charlie ',
      '{% sorted_for i in array %}{{ i }} {% endsorted_for %}',
      'array' => ['charlie', 'alpha', 'Beta'])
  end

  def test_case_sensitive
    assert_template_result(
      'Beta alpha charlie ',
      '{% sorted_for i in array case_sensitive:true %}{{ i }} {% endsorted_for %}',
      'array' => ['charlie', 'alpha', 'Beta'])
  end
end

class SortedForNestedContainerTest < Test::Unit::TestCase
  include Liquid

  def test_nested_list_sorted_for
    assert_template_result(
      '1 2 3 4 5 6 7 8 9 ',
      '{% for i in (0..2) %}{% assign subnested = nested[i] %}' \
      '{% sorted_for j in subnested %}{{ j }} {% endsorted_for %}{% endfor %}',
      'nested' => [[3, 2, 1], [6, 5, 4], [9, 8, 7]])
  end

  def test_nested_parallel_hash_sorted_keys_for
    assert_template_result(
      'a (one two three ) b (four five six ) c (seven eight nine ) ',
      '{% sorted_keys_for i in nested %}{{ i }} (' \
      '{% assign subnested = nested[i] %}'\
      '{% sorted_keys_for j in subnested %}{{ subnested[j] }} ' \
      '{% endsorted_keys_for %}) {% endsorted_keys_for %}',
      'nested' => {
        'b'=>{6=>"six", 5=>"five", 4=>"four"},
        'c'=>{9=>"nine", 7=>"seven", 8=>"eight"},
        'a'=>{2=>"two", 3=>"three", 1=>"one"}})
  end

  def test_nested_hash_of_hashes_sorted_keys_for
    assert_template_result(
      'a (one two three ) b (four five six ) c (seven eight nine ) ',
      '{% sorted_keys_for i in nested %}' \
      '{% assign outer = nested[i] %}{{ outer.key }} (' \
      '{% sorted_keys_for j in outer.values %}{{ outer.values[j] }} ' \
      '{% endsorted_keys_for %}) {% endsorted_keys_for %}',
      'nested' => {
        'B'=>{'key'=>'b', 'values'=>{6=>"six", 5=>"five", 4=>"four"}},
        'C'=>{'key'=>'c', 'values'=>{9=>"nine", 7=>"seven", 8=>"eight"}},
        'A'=>{'key'=>'a', 'values'=>{2=>"two", 3=>"three", 1=>"one"}}})
  end
end

Thank you this plugin was just what I needed!

Thank you so much!. This plug-in is great. Now I can sort my articles by date (I have an articles collection in addition to blog posts).

Awesome plugin, pretty silly that this isn't in the Jekyll core already. 👊