Module: Sass::Plugin

Module

Sass::Plugin

In:

lib/sass/plugin.rb
lib/sass/plugin/rack.rb
lib/sass/plugin/staleness_checker.rb
lib/sass/plugin/configuration.rb

dot/m_86_0.png

This module handles the compilation of Sass/SCSS files. It provides global options and checks whether CSS files need to be updated.

This module is used as the primary interface with Sass when it‘s used as a plugin for various frameworks. All Rack-enabled frameworks are supported out of the box. The plugin is {file:SASS_REFERENCE.md#rails_merb_plugin automatically activated for Rails and Merb}. Other frameworks must enable it explicitly; see {Sass::Plugin::Rack}.

This module has a large set of callbacks available to allow users to run code (such as logging) when certain things happen. All callback methods are of the form `on_#{name}`, and they all take a block that‘s called when the given action occurs.

@example Using a callback Sass::Plugin.on_updating_stylesheet do |template, css|

  puts "Compiling #{template} to #{css}"

end Sass::Plugin.update_stylesheets

  #=> Compiling app/sass/screen.scss to public/stylesheets/screen.css
  #=> Compiling app/sass/print.scss to public/stylesheets/print.css
  #=> Compiling app/sass/ie.scss to public/stylesheets/ie.css

Methods

add_template_location check_for_updates css_filename css_locations engine_options forbid_update? force_update_stylesheets load_paths normalize_template_location! options= remove_template_location stylesheet_needs_update? template_location_array template_locations try_delete_css update_stylesheet update_stylesheets watch

Included Modules

Haml::Util Sass::Callbacks

Classes and Modules

Class Sass::Plugin::MerbBootLoader
Class Sass::Plugin::Rack
Class Sass::Plugin::StalenessChecker

Attributes

checked_for_updates	[R]	Whether or not Sass has *ever* checked if the stylesheets need to be updated (in this Ruby instance). @return [Boolean]
options	[R]	An options hash. See {file:SASS_REFERENCE.md#sass_options the Sass options documentation}. @return [{Symbol => Object}]

Public Instance methods

add_template_location(template_location, css_location = options[:css_location])

Adds a new template-location/css-location mapping. This means that Sass/SCSS files in `template_location` will be compiled to CSS files in `css_location`.

This is preferred over manually manipulating the {file:SASS_REFERENCE.md#template_location-option `:template_location` option} since the option can be in multiple formats.

Note that this method will change `options[:template_location]` to be in the Array format. This means that even if `options[:template_location]` had previously been a Hash or a String, it will now be an Array.

@param template_location [String] The location where Sass/SCSS files will be. @param css_location [String] The location where compiled CSS files will go.

     # File lib/sass/plugin/configuration.rb, line 161
161:     def add_template_location(template_location, css_location = options[:css_location])
162:       normalize_template_location!
163:       template_location_array << [template_location, css_location]
164:     end

check_for_updates()

Same as \{update_stylesheets}, but respects \{checked_for_updates} and the {file:SASS_REFERENCE.md#always_update-option `:always_update`} and {file:SASS_REFERENCE.md#always_check-option `:always_check`} options.

@see update_stylesheets

    # File lib/sass/plugin.rb, line 47
47:     def check_for_updates
48:       return unless !Sass::Plugin.checked_for_updates ||
49:           Sass::Plugin.options[:always_update] || Sass::Plugin.options[:always_check]
50:       update_stylesheets
51:     end

engine_options(additional_options = {})

Non-destructively modifies \{options} so that default values are properly set.

@param additional_options [{Symbol => Object}] An options hash with which to merge \{options} @return [{Symbol => Object}] The modified options hash

     # File lib/sass/plugin/configuration.rb, line 140
140:     def engine_options(additional_options = {})
141:       opts = options.dup.merge(additional_options)
142:       opts[:load_paths] = load_paths(opts)
143:       opts
144:     end

force_update_stylesheets(individual_files = [])

Updates all stylesheets, even those that aren‘t out-of-date. Ignores the cache.

@param individual_files [Array<(String, String)>]

  A list of files to check for updates
  **in addition to those specified by the
  {file:SASS_REFERENCE.md#template_location-option `:template_location` option}.**
  The first string in each pair is the location of the Sass/SCSS file,
  the second is the location of the CSS file that it should be compiled to.

@see update_stylesheets

     # File lib/sass/plugin.rb, line 103
103:     def force_update_stylesheets(individual_files = [])
104:       old_options = options
105:       self.options = options.dup
106:       options[:never_update] = false
107:       options[:always_update] = true
108:       options[:cache] = false
109:       update_stylesheets(individual_files)
110:     ensure
111:       self.options = old_options
112:     end

options=(value)

Sets the options hash. See {file:SASS_REFERENCE.md#sass_options the Sass options documentation}.

@param value [{Symbol => Object}] The options hash

     # File lib/sass/plugin/configuration.rb, line 132
132:     def options=(value)
133:       @options.merge!(value)
134:     end

remove_template_location(template_location, css_location = options[:css_location])

Removes a template-location/css-location mapping. This means that Sass/SCSS files in `template_location` will no longer be compiled to CSS files in `css_location`.

This is preferred over manually manipulating the {file:SASS_REFERENCE.md#template_location-option `:template_location` option} since the option can be in multiple formats.

Note that this method will change `options[:template_location]` to be in the Array format. This means that even if `options[:template_location]` had previously been a Hash or a String, it will now be an Array.

@param template_location [String]

  The location where Sass/SCSS files were,
  which is now going to be ignored.

@param css_location [String]

  The location where compiled CSS files went, but will no longer go.

@return [Boolean]

  Non-`nil` if the given mapping already existed and was removed,
  or `nil` if nothing was changed.

     # File lib/sass/plugin/configuration.rb, line 187
187:     def remove_template_location(template_location, css_location = options[:css_location])
188:       normalize_template_location!
189:       template_location_array.delete([template_location, css_location])
190:     end

template_location_array()

Returns the template locations configured for Sass as an array of `[template_location, css_location]` pairs. See the {file:SASS_REFERENCE.md#template_location-option `:template_location` option} for details.

@return [Array<(String, String)>]

  An array of `[template_location, css_location]` pairs.

     # File lib/sass/plugin/configuration.rb, line 199
199:     def template_location_array
200:       old_template_location = options[:template_location]
201:       normalize_template_location!
202:       options[:template_location]
203:     ensure
204:       options[:template_location] = old_template_location
205:     end

update_stylesheets(individual_files = [])

Updates out-of-date stylesheets.

Checks each Sass/SCSS file in {file:SASS_REFERENCE.md#template_location-option `:template_location`} to see if it‘s been modified more recently than the corresponding CSS file in {file:SASS_REFERENCE.md#css_location-option `:css_location`}. If it has, it updates the CSS file.

@param individual_files [Array<(String, String)>]

  A list of files to check for updates
  **in addition to those specified by the
  {file:SASS_REFERENCE.md#template_location-option `:template_location` option}.**
  The first string in each pair is the location of the Sass/SCSS file,
  the second is the location of the CSS file that it should be compiled to.

    # File lib/sass/plugin.rb, line 66
66:     def update_stylesheets(individual_files = [])
67:       return if options[:never_update]
68: 
69:       run_updating_stylesheets individual_files
70: 
71:       individual_files.each {|t, c| update_stylesheet(t, c)}
72: 
73:       @checked_for_updates = true
74:       staleness_checker = StalenessChecker.new
75: 
76:       template_location_array.each do |template_location, css_location|
77: 
78:         Dir.glob(File.join(template_location, "**", "*.s[ca]ss")).sort.each do |file|
79:           # Get the relative path to the file
80:           name = file.sub(template_location.sub(/\/*$/, '/'), "")
81:           css = css_filename(name, css_location)
82: 
83:           next if forbid_update?(name)
84:           if options[:always_update] || staleness_checker.stylesheet_needs_update?(css, file)
85:             update_stylesheet file, css
86:           else
87:             run_not_updating_stylesheet file, css
88:           end
89:         end
90:       end
91:     end

watch(individual_files = [])

Watches the template directory (or directories) and updates the CSS files whenever the related Sass/SCSS files change. `watch` never returns.

Whenever a change is detected to a Sass/SCSS file in {file:SASS_REFERENCE.md#template_location-option `:template_location`}, the corresponding CSS file in {file:SASS_REFERENCE.md#css_location-option `:css_location`} will be recompiled. The CSS files of any Sass/SCSS files that import the changed file will also be recompiled.

Before the watching starts in earnest, `watch` calls \{update_stylesheets}.

Note that `watch` uses the [FSSM](github.com/ttilley/fssm) library to monitor the filesystem for changes. FSSM isn‘t loaded until `watch` is run. The version of FSSM distributed with Sass is loaded by default, but if another version has already been loaded that will be used instead.

@param individual_files [Array<(String, String)>]

  A list of files to watch for updates
  **in addition to those specified by the
  {file:SASS_REFERENCE.md#template_location-option `:template_location` option}.**
  The first string in each pair is the location of the Sass/SCSS file,
  the second is the location of the CSS file that it should be compiled to.

     # File lib/sass/plugin.rb, line 138
138:     def watch(individual_files = [])
139:       update_stylesheets(individual_files)
140: 
141:       begin
142:         require 'fssm'
143:       rescue LoadError => e
144:         e.message << "\n" <<
145:           if File.exists?(scope(".git"))
146:             'Run "git submodule update --init" to get the recommended version.'
147:           else
148:             'Run "gem install fssm" to get it.'
149:           end
150:         raise e
151:       end
152: 
153:       unless individual_files.empty? && FSSM::Backends::Default.name == "FSSM::Backends::FSEvents"
154:         # As of FSSM 0.1.4, it doesn't support FSevents on individual files,
155:         # but it also isn't smart enough to switch to polling itself.
156:         require 'fssm/backends/polling'
157:         Haml::Util.silence_warnings do
158:           FSSM::Backends.const_set(:Default, FSSM::Backends::Polling)
159:         end
160:       end
161: 
162:       # TODO: Keep better track of what depends on what
163:       # so we don't have to run a global update every time anything changes.
164:       FSSM.monitor do |mon|
165:         template_location_array.each do |template_location, css_location|
166:           mon.path template_location do |path|
167:             path.glob '**/*.s[ac]ss'
168: 
169:             path.update do |base, relative|
170:               run_template_modified File.join(base, relative)
171:               update_stylesheets(individual_files)
172:             end
173: 
174:             path.create do |base, relative|
175:               run_template_created File.join(base, relative)
176:               update_stylesheets(individual_files)
177:             end
178: 
179:             path.delete do |base, relative|
180:               run_template_deleted File.join(base, relative)
181:               css = File.join(css_location, relative.gsub(/\.s[ac]ss$/, '.css'))
182:               try_delete_css css
183:               update_stylesheets(individual_files)
184:             end
185:           end
186:         end
187: 
188:         individual_files.each do |template, css|
189:           mon.file template do |path|
190:             path.update do
191:               run_template_modified template
192:               update_stylesheets(individual_files)
193:             end
194: 
195:             path.create do
196:               run_template_created template
197:               update_stylesheets(individual_files)
198:             end
199: 
200:             path.delete do
201:               run_template_deleted template
202:               try_delete_css css
203:               update_stylesheets(individual_files)
204:             end
205:           end
206:         end
207:       end
208:     end

Private Instance methods

css_filename(name, path)

     # File lib/sass/plugin.rb, line 252
252:     def css_filename(name, path)
253:       "#{path}/#{name}".gsub(/\.s[ac]ss$/, '.css')
254:     end

css_locations()

     # File lib/sass/plugin.rb, line 248
248:     def css_locations
249:       template_location_array.to_a.map {|l| l.last}
250:     end

forbid_update?(name)

     # File lib/sass/plugin.rb, line 256
256:     def forbid_update?(name)
257:       name.sub(/^.*\//, '')[0] == ?_
258:     end

load_paths(opts = options)

     # File lib/sass/plugin.rb, line 240
240:     def load_paths(opts = options)
241:       (opts[:load_paths] || []) + template_locations
242:     end

normalize_template_location!()

     # File lib/sass/plugin/configuration.rb, line 209
209:     def normalize_template_location!
210:       return if options[:template_location].is_a?(Array)
211:       options[:template_location] =
212:         case options[:template_location]
213:         when nil
214:           css_location = options[:css_location] || './public/stylesheets'
215:           [[File.join(css_location, 'sass'), css_location]]
216:         when String; [[options[:template_location], options[:css_location]]]
217:         else; options[:template_location].to_a
218:         end
219:     end

stylesheet_needs_update?(css_file, template_file)

Compass expects this to exist

     # File lib/sass/plugin.rb, line 261
261:     def stylesheet_needs_update?(css_file, template_file)
262:       StalenessChecker.stylesheet_needs_update?(css_file, template_file)
263:     end

template_locations()

     # File lib/sass/plugin.rb, line 244
244:     def template_locations
245:       template_location_array.to_a.map {|l| l.first}
246:     end

try_delete_css(css)

     # File lib/sass/plugin.rb, line 234
234:     def try_delete_css(css)
235:       return unless File.exists?(css)
236:       run_deleting_css css
237:       File.delete css
238:     end

update_stylesheet(filename, css)

     # File lib/sass/plugin.rb, line 212
212:     def update_stylesheet(filename, css)
213:       dir = File.dirname(css)
214:       unless File.exists?(dir)
215:         run_creating_directory dir
216:         FileUtils.mkdir_p dir
217:       end
218: 
219:       begin
220:         result = Sass::Files.tree_for(filename, engine_options(:css_filename => css, :filename => filename)).render
221:       rescue Exception => e
222:         run_compilation_error e, filename, css
223:         result = Sass::SyntaxError.exception_to_css(e, options)
224:       else
225:         run_updating_stylesheet filename, css
226:       end
227: 
228:       # Finally, write the file
229:       flag = 'w'
230:       flag = 'wb' if Haml::Util.windows? && options[:unix_newlines]
231:       File.open(css, flag) {|file| file.print(result)}
232:     end