Change nils argument to string

features/embed_filters.feature

@@ -101,7 +101,7 @@ Feature: Embed filters
     And I have the following page:
       | layout | content |
       | default | Jump |
-    And I have a default layout that contains "{% assign sorted_pages = site.pages | sort: 'title', true %}The rule of {{ sorted_pages.size }}: {% for p in sorted_pages %}{{ p.content | strip_html | strip_newlines }}, {% endfor %}"
+    And I have a default layout that contains "{% assign sorted_pages = site.pages | sort: 'title', 'last' %}The rule of {{ sorted_pages.size }}: {% for p in sorted_pages %}{{ p.content | strip_html | strip_newlines }}, {% endfor %}"
     When I run jekyll build
     Then the _site directory should exist
     And I should see exactly "The rule of 3: Fly, Run, Jump," in "_site/bird.html"

lib/jekyll/filters.rb

@@ -194,18 +194,18 @@ module Jekyll
     #
     # input - the object array
     # key - key within each object to filter by
-    # nils_last - nils appear after non-nil values in the sort ordering
+    # nils ('first' | 'last') - nils appear before or after non-nil values
     #
     # Returns the filtered array of objects
-    def sort(input, key = nil, nils_last = false)
+    def sort(input, key = nil, nils = 'first')
       if key.nil?
         input.sort
       else
         input.sort { |a, b|
           if a[key].nil? and !b[key].nil?
-            nils_last ? +1 : -1
+            nils == 'first' ? -1 : +1
           elsif !a[key].nil? and b[key].nil?
-            nils_last ? -1 : +1
+            nils == 'first' ? +1 : -1
           else
             a[key] <=> b[key]
           end

site/docs/templates.md

@@ -187,12 +187,13 @@ common tasks easier.
     <tr>
       <td>
         <p class="name"><strong>Sort</strong></p>
-        <p>Sort array. Optional arguments: property, nils last.</p>
+        <p>Sort array. Optional arguments: property name; nils order (*first* or *last*).</p>
       </td>
       <td class="align-center">
         <p>
          <code class="filter">{% raw %}{{ page.tags | sort }}{% endraw %}</code>
-         <code class="filter">{% raw %}{{ site.pages | sort: 'title', true }}{% endraw %}</code>
+         <code class="filter">{% raw %}{{ site.posts | sort: 'author' }}{% endraw %}</code>
+         <code class="filter">{% raw %}{{ site.pages | sort: 'title', 'last' }}{% endraw %}</code>
         </p>
       </td>
     </tr>

test/test_filters.rb

@@ -169,11 +169,11 @@ class TestFilters < Test::Unit::TestCase
       should "return sorted by property array with nils first" do
         ary = [{"a" => 2}, {"b" => 1}, {"a" => 1}]
         assert_equal [{"b" => 1}, {"a" => 1}, {"a" => 2}], @filter.sort(ary, "a")
-        assert_equal @filter.sort(ary, "a"), @filter.sort(ary, "a", false)
+        assert_equal @filter.sort(ary, "a"), @filter.sort(ary, "a", "first")
       end
       should "return sorted by property array with nils last" do
         assert_equal [{"a" => 1}, {"a" => 2}, {"b" => 1}],
-          @filter.sort([{"a" => 2}, {"b" => 1}, {"a" => 1}], "a", true)
+          @filter.sort([{"a" => 2}, {"b" => 1}, {"a" => 1}], "a", "last")
       end
     end