add bibliography templates

#19

features/bibtex.feature

@@ -90,6 +90,34 @@ Feature: BibTeX
     And the "_site/scholar.html" file should exist
     And I should see "<i>The Ruby Programming Language</i>" in "_site/scholar.html"
 
+  @tags @bibliography @config
+  Scenario: Simple Bibliography With Custom Template
+    Given I have a scholar configuration with:
+      | key                   | value                             |
+      | source                | ./_bibliography                   |
+      | bibliography_template | <abbr>[%{key}]</abbr>%{reference} |
+    And I have a "_bibliography" directory
+    And I have a file "_bibliography/references.bib":
+      """
+      @book{ruby,
+        title     = {The Ruby Programming Language},
+        author    = {Flanagan, David and Matsumoto, Yukihiro},
+        year      = {2008},
+        publisher = {O'Reilly Media}
+      }
+      """
+    And I have a page "scholar.html":
+      """
+      ---
+      ---
+      {% bibliography -f references %}
+      """
+    When I run jekyll
+    Then the _site directory should exist
+    And the "_site/scholar.html" file should exist
+    And I should see "<i>The Ruby Programming Language</i>" in "_site/scholar.html"
+    And I should see "<abbr>\[ruby\]</abbr><span" in "_site/scholar.html"
+
   @tags @filter
   Scenario: Filtered Bibliography Loaded From Default Directory
     Given I have a scholar configuration with:

features/reference.feature

@@ -29,7 +29,7 @@ Feature: Formatted References
     And the "_site/scholar.html" file should exist
     And I should see "Matsumoto, Y. \(2008\). <i>The Ruby" in "_site/scholar.html"
 
-  @tags @reference
+  @tags @reference @missing
   Scenario: Missing references
     Given I have a scholar configuration with:
       | key          | value             |
@@ -54,4 +54,33 @@ Feature: Formatted References
     When I run jekyll
     Then the _site directory should exist
     And the "_site/scholar.html" file should exist
-    And I should see "missing reference" in "_site/scholar.html"
+    And I should see "(missing reference)" in "_site/scholar.html"
+
+  @tags @reference @missing
+  Scenario: Missing references with a custom text
+    Given I have a scholar configuration with:
+      | key                | value             |
+      | source             | ./_bibliography   |
+      | bibliography       | my_references     |
+      | missing_reference  | not found!        |
+    And I have a "_bibliography" directory
+    And I have a file "_bibliography/my_references.bib":
+      """
+      @book{ruby,
+        title     = {The Ruby Programming Language},
+        author    = {Flanagan, David and Matsumoto, Yukihiro},
+        year      = {2008},
+        publisher = {O'Reilly Media}
+      }
+      """
+    And I have a page "scholar.html":
+      """
+      ---
+      ---
+      {% reference java %}
+      """
+    When I run jekyll
+    Then the _site directory should exist
+    And the "_site/scholar.html" file should exist
+    And I should see "not found!" in "_site/scholar.html"
+    And I should not see "(missing reference)" in "_site/scholar.html"

lib/jekyll/scholar/defaults.rb

 module Jekyll
   class Scholar
-    @defaults = Hash[*%w{
+    @defaults = {
+      'style'                 => 'apa',
+      'locale'                => 'en',
 
-      style        apa
-      locale       en
+      'sort_by'               => 'none',
+      'order'                 => 'ascending',
 
-      sort_by      none
-      order        ascending
+      'source'                => './_bibliography',
+      'bibliography'          => 'references.bib',
 
-      source       ./_bibliography
-      bibliography references.bib
+      'details_dir'           => 'bibliography',
+      'details_layout'        => 'bibtex.html',
+      'details_link'          => 'Details',
 
-      details_dir    bibliography
-      details_layout bibtex.html
-      details_link   Details
-      
-      bibliography_class bibliography
-      details_link_class details
+      'bibliography_class'    => 'bibliography',
+      'bibliography_template' => '%{reference}',
 
-    	query  @*
-	
-    }].freeze
+      'reference_tagname'     => 'span',
+      'missing_reference'     => '(missing reference)',
+
+      'details_link_class'    => 'details',
+
+    	'query'                 => '@*'
+
+    }.freeze
 
     class << self
       attr_reader :defaults

lib/jekyll/scholar/tags/bibliography.rb

@@ -24,7 +24,7 @@ module Jekyll
         end
 
         references.map! do |entry|
-          reference = reference_tag entry
+          reference = bibliography_tag entry
 
           if generate_details?
             reference << link_to(details_link_for(entry),

lib/jekyll/scholar/utilities.rb

@@ -80,13 +80,35 @@ module Jekyll
       end
 
       def reference_tag(entry)
-        return '(missing reference)' unless entry
+        return missing_reference unless entry
 
         entry = entry.convert(:latex)
         reference = CiteProc.process entry.to_citeproc,
           :style => config['style'], :locale => config['locale'], :format => 'html'
 
-        content_tag :span, reference, :id => [prefix, entry.key].compact.join('-')
+        content_tag reference_tagname, reference,
+          :id => [prefix, entry.key].compact.join('-')
+      end
+
+      def missing_reference
+        config['missing_reference']
+      end
+
+      def reference_tagname
+        config['reference_tagname'] || :span
+      end
+
+      def bibliography_template
+        config['bibliography_template'] || '%{reference}'
+      end
+
+      def bibliography_tag(entry)
+        return missing_reference unless entry
+
+        bibliography_template % {
+          :reference => reference_tag(entry),
+          :key => entry.key
+        }
       end
 
       def generate_details?