class Haml::Buffer
This class is used only internally. It holds the buffer of HTML that is eventually output as the resulting document. It's called from within the precompiled code, and helps reduce the amount of processing done within `instance_eval`ed code.
Attributes
@return [Boolean] @see active?
The string that holds the compiled HTML. This is aliased as `_erbout` for compatibility with ERB-specific code.
@return [String]
nil if there's no capture_haml block running, and the position at which it's beginning the capture if there is one.
@return [Fixnum, nil]
The options hash passed in from {Haml::Engine}.
@return [{String => Object}] @see Haml::Options#for_buffer
The {Buffer} for the enclosing Haml document. This is set for partials and similar sorts of nested templates. It's `nil` at the top level (see {#toplevel?}).
@return [Buffer]
Public Class Methods
Merges two attribute hashes. This is the same as `to.merge!(from)`, except that it merges id, class, and data attributes.
ids are concatenated with `“_”`, and classes are concatenated with `“ ”`. data hashes are simply merged.
Destructively modifies both `to` and `from`.
@param to [{String => String}] The attribute hash to merge into @param from [{String => to_s}] The attribute hash to merge from @return [{String => String}] `to`, after being merged
# File lib/haml/buffer.rb, line 233 def self.merge_attrs(to, from) from['id'] = Compiler.filter_and_join(from['id'], '_') if from['id'] if to['id'] && from['id'] to['id'] << '_' << from.delete('id').to_s elsif to['id'] || from['id'] from['id'] ||= to['id'] end from['class'] = Compiler.filter_and_join(from['class'], ' ') if from['class'] if to['class'] && from['class'] # Make sure we don't duplicate class names from['class'] = (from['class'].to_s.split(' ') | to['class'].split(' ')).sort.join(' ') elsif to['class'] || from['class'] from['class'] ||= to['class'] end from_data = from.delete('data') || {} to_data = to.delete('data') || {} # forces to_data & from_data into a hash from_data = { nil => from_data } unless from_data.is_a?(Hash) to_data = { nil => to_data } unless to_data.is_a?(Hash) merged_data = to_data.merge(from_data) to['data'] = merged_data unless merged_data.empty? to.merge!(from) end
@param upper [Buffer] The parent buffer @param options [{Symbol => Object}] An options hash.
See {Haml::Engine#options\_for\_buffer}
# File lib/haml/buffer.rb, line 90 def initialize(upper = nil, options = {}) @active = true @upper = upper @options = options @buffer = new_encoded_string @tabulation = 0 # The number of tabs that Engine thinks we should have # @real_tabs + @tabulation is the number of tabs actually output @real_tabs = 0 end
Public Instance Methods
Whether or not this buffer is currently being used to render a Haml template. Returns `false` if a subtemplate is being rendered, even if it's a subtemplate of this buffer's template.
@return [Boolean]
# File lib/haml/buffer.rb, line 70 def active? @active end
Modifies the indentation of the document.
@param tab_change [Fixnum] The number of tabs by which to increase
or decrease the document's indentation
# File lib/haml/buffer.rb, line 126 def adjust_tabs(tab_change) @real_tabs += tab_change end
# File lib/haml/buffer.rb, line 199 def attributes(class_id, obj_ref, *attributes_hashes) attributes = class_id attributes_hashes.each do |old| self.class.merge_attrs(attributes, Hash[old.map {|k, v| [k.to_s, v]}]) end self.class.merge_attrs(attributes, parse_object_ref(obj_ref)) if obj_ref Compiler.build_attributes( html?, @options[:attr_wrapper], @options[:escape_attrs], @options[:hyphenate_data_attrs], attributes) end
@return [Boolean] Whether or not the format is HTML4
# File lib/haml/buffer.rb, line 50 def html4? @options[:format] == :html4 end
@return [Boolean] Whether or not the format is HTML5.
# File lib/haml/buffer.rb, line 55 def html5? @options[:format] == :html5 end
@return [Boolean] Whether or not the format is any flavor of HTML
# File lib/haml/buffer.rb, line 45 def html? html4? or html5? end
Appends text to the buffer, properly tabulated. Also modifies the document's indentation.
@param text [String] The text to append @param tab_change [Fixnum] The number of tabs by which to increase
or decrease the document's indentation
@param dont_tab_up [Boolean] If true, don't indent the first line of `text`
# File lib/haml/buffer.rb, line 109 def push_text(text, tab_change, dont_tab_up) if @tabulation > 0 # Have to push every line in by the extra user set tabulation. # Don't push lines with just whitespace, though, # because that screws up precompiled indentation. text.gsub!(/^(?!\s+$)/m, tabs) text.sub!(tabs, '') if dont_tab_up end @buffer << text @real_tabs += tab_change end
Remove the whitespace from the right side of the buffer string. Doesn't do anything if we're at the beginning of a capture_haml block.
# File lib/haml/buffer.rb, line 211 def rstrip! if capture_position.nil? buffer.rstrip! return end buffer << buffer.slice!(capture_position..-1).rstrip end
@return [Fixnum] The current indentation level of the document
# File lib/haml/buffer.rb, line 75 def tabulation @real_tabs + @tabulation end
Sets the current tabulation of the document.
@param val [Fixnum] The new tabulation
# File lib/haml/buffer.rb, line 82 def tabulation=(val) val = val - @real_tabs @tabulation = val > -1 ? val : 0 end
@return [Boolean] Whether or not this buffer is a top-level template,
as opposed to a nested partial
# File lib/haml/buffer.rb, line 61 def toplevel? upper.nil? end
@return [Boolean] Whether or not the format is XHTML
# File lib/haml/buffer.rb, line 40 def xhtml? not html? end
Private Instance Methods
Works like #{find_and_preserve}, but allows the first newline after a preserved opening tag to remain unencoded, and then outdents the content. This change was motivated primarily by the change in Rails 3.2.3 to emit a newline after textarea helpers.
@param input [String] The text to process @since Haml 4.0.1 @private
# File lib/haml/buffer.rb, line 272 def fix_textareas!(input) pattern = /([ ]*)<(textarea)([^>]*)>(\n|
)(.*?)(<\/\2>)/im input.gsub!(pattern) do |s| match = pattern.match(s) content = match[5] if match[4] == '
' content.sub!(/\A /, ' ') else content.sub!(/\A[ ]*/, '') end "#{match[1]}<#{match[2]}#{match[3]}>\n#{content}</#{match[2]}>" end end
# File lib/haml/buffer.rb, line 287 def new_encoded_string "" end
Takes an array of objects and uses the class and id of the first one to create an attributes hash. The second object, if present, is used as a prefix, just like you can do with `dom_id()` and `dom_class()` in Rails
# File lib/haml/buffer.rb, line 307 def parse_object_ref(ref) prefix = ref[1] ref = ref[0] # Let's make sure the value isn't nil. If it is, return the default Hash. return {} if ref.nil? class_name = if ref.respond_to?(:haml_object_ref) ref.haml_object_ref else underscore(ref.class) end ref_id = if ref.respond_to?(:to_key) key = ref.to_key key.join('_') unless key.nil? else ref.id end id = "#{class_name}_#{ref_id || 'new'}" if prefix class_name = "#{ prefix }_#{ class_name}" id = "#{ prefix }_#{ id }" end {'id' => id, 'class' => class_name} end
Gets `count` tabs. Mostly for internal use.
# File lib/haml/buffer.rb, line 298 def tabs(count = 0) tabs = [count + @tabulation, 0].max @@tab_cache[tabs] ||= ' ' * tabs end
Changes a word from camel case to underscores. Based on the method of the same name in Rails' Inflector, but copied here so it'll run properly without Rails.
# File lib/haml/buffer.rb, line 337 def underscore(camel_cased_word) camel_cased_word.to_s.gsub(/::/, '_'). gsub(/([A-Z]+)([A-Z][a-z])/,'\1_\2'). gsub(/([a-z\d])([A-Z])/,'\1_\2'). tr("-", "_"). downcase end