Adds in new search,list svg icons and blacklight_icons helper

This commit adds in several things:

 - Blacklight::Icons - a svg icon reader class
 - Blacklight::IconHelperBehavior - a helper that calls and wraps in a span,
   also caches the svg lookups
 - svg icons for search, and list. Both optimized for size reduction.

Link to sketch document used to create svgs: https://drive.google.com/open?id=0BzWuWHFTTIPES0tXUnkwQXZNaFk

app/assets/stylesheets/blacklight/_blacklight_base.scss

@@ -21,3 +21,4 @@
 @import "blacklight/search_history";
 @import "blacklight/modal";
 @import "blacklight/twitter_typeahead";
+@import 'blacklight/icons';

app/assets/stylesheets/blacklight/_icons.scss

@@ -0,0 +1,42 @@
+.blacklight-icons {
+  display: inline-block;
+  height: $font-size-root;
+  width: $font-size-root;
+  vertical-align: text-top;
+}
+
+.btn-primary {
+  .blacklight-icons g {
+    stroke: $btn-primary-color;
+  }
+}
+
+.btn-secondary {
+  .blacklight-icons g {
+    stroke: $btn-secondary-color;
+  }
+}
+
+.btn-info {
+  .blacklight-icons g {
+    stroke: $btn-info-color;
+  }
+}
+
+.btn-success {
+  .blacklight-icons g {
+    stroke: $btn-success-color;
+  }
+}
+
+.btn-warning {
+  .blacklight-icons g {
+    stroke: $btn-warning-color;
+  }
+}
+
+.btn-danger {
+  .blacklight-icons g {
+    stroke: $btn-danger-color;
+  }
+}

app/helpers/blacklight/blacklight_helper_behavior.rb

@@ -4,6 +4,7 @@ module Blacklight::BlacklightHelperBehavior
   include UrlHelperBehavior
   include HashAsHiddenFieldsHelperBehavior
   include LayoutHelperBehavior
+  include IconHelperBehavior
 
   ##
   # Get the name of this application, from either:

app/helpers/blacklight/catalog_helper_behavior.rb

@@ -244,16 +244,17 @@ def thumbnail_url document
   # @param [String] view
   # @return [String]
   def render_view_type_group_icon view
-    content_tag :span, '', class: "glyphicon #{blacklight_config.view[view].icon_class || default_view_type_group_icon_classes(view)}"
+    blacklight_icon(view)
   end
 
   ##
   # Get the default view type classes for a view in the results view picker
   #
   # @param [String] view
   # @return [String]
-  def default_view_type_group_icon_classes view
-    "glyphicon-#{view.to_s.parameterize} view-icon-#{view.to_s.parameterize}"
+  def default_view_type_group_icon_classes _view
+    Deprecation.warn(Blacklight::CatalogHelperBehavior, 'This method has been deprecated, use blacklight_icons helper instead')
+    ''
   end
 
   def current_bookmarks documents_or_response = nil

app/helpers/blacklight/icon_helper_behavior.rb

@@ -0,0 +1,16 @@
+##
+# Module to help generate icon helpers for SVG images
+module Blacklight::IconHelperBehavior
+  ##
+  # Returns the raw SVG (String) for a Blacklight Icon located in 
+  # app/assets/images/blacklight/*.svg. Caches them so we don't have to look up
+  # the svg everytime.
+  # @param [String, Symbol] icon_name
+  # @return [String]
+  def blacklight_icon(icon_name, options = {})
+    Rails.cache.fetch("blacklight_icons/#{icon_name}") do
+      icon = Blacklight::Icon.new(icon_name, options)
+      content_tag(:span, icon.svg.html_safe, icon.options)
+    end    
+  end
+end

app/models/blacklight/icon.rb

@@ -0,0 +1,51 @@
+module Blacklight
+  class Icon
+    attr_reader :icon_name
+    ##
+    # @param [String, Symbol] icon_name
+    # @param [Hash] options
+    # @param [String] classes additional classes separated by a string
+    def initialize(icon_name, classes: '')
+      @icon_name = icon_name
+      @classes = classes
+    end
+
+    ##
+    # Returns the raw source, but you could extend this to add additional attributes
+    # @return [String]
+    def svg
+      file_source
+    end
+
+    ##
+    # @return [Hash]
+    def options
+      {
+        class: classes
+      }
+    end
+
+    ##
+    # @return [String]
+    def path
+      "blacklight/#{icon_name}.svg"
+    end
+
+    ##
+    # @return [String]
+    def file_source
+      raise Blacklight::Exceptions::IconNotFound, "Could not find #{path}" if file.blank?
+      file.source.force_encoding('UTF-8')
+    end
+
+    private
+
+    def file
+      Rails.application.assets.find_asset(path)
+    end
+
+    def classes
+      " blacklight-icons #{@classes} ".strip
+    end
+  end
+end

app/views/catalog/_search_form.html.erb

@@ -20,7 +20,7 @@
     <span class="input-group-btn">
       <button type="submit" class="btn btn-primary search-btn" id="search">
         <span class="submit-search-text"><%= t('blacklight.search.form.submit') %></span>
-        <span class="glyphicon glyphicon-search"></span>
+        <%= blacklight_icon :search %>
       </button>
     </span>
   </div>

lib/blacklight/exceptions.rb

@@ -14,5 +14,8 @@ class ExpiredSessionToken < StandardError
     end
 
     class ECONNREFUSED < ::Errno::ECONNREFUSED; end
+
+    class IconNotFound < StandardError
+    end
   end
 end

spec/helpers/blacklight/icon_helper_behavior_spec.rb

@@ -0,0 +1,8 @@
+RSpec.describe Blacklight::IconHelperBehavior do
+  describe '#blacklight_icon' do
+    it 'wraps the svg in a span with classes' do
+      expect(helper.blacklight_icon(:search))
+        .to have_css 'span.blacklight-icons svg'
+    end
+  end
+end

spec/models/blacklight/icon_spec.rb

@@ -0,0 +1,34 @@
+RSpec.describe Blacklight::Icon do
+  subject { described_class.new(:search, classes: 'awesome') }
+  describe '#svg' do
+    it 'returns a string' do
+      expect(subject.svg).to be_an String
+    end
+    it 'returns raw svg' do
+      expect(Capybara.string(subject.svg))
+        .to have_css 'svg title', text: 'Search'
+    end
+  end
+  describe '#options' do
+    it 'applies options classes and default class' do
+      expect(subject.options[:class]).to eq 'blacklight-icons awesome'
+    end
+  end
+  describe '#path' do
+    it 'prepends blacklight and sufixes .svg' do
+      expect(subject.path).to eq 'blacklight/search.svg'
+    end
+  end
+  describe 'file_source' do
+    context 'file is not available' do
+      subject { described_class.new(:yolo) }
+      it { expect { subject.file_source }
+        .to raise_error(Blacklight::Exceptions::IconNotFound) }
+    end
+    context 'file is available' do
+      it 'returns the filesource' do
+        expect(subject.file_source).to include '<svg'
+      end
+    end
+  end
+end