require 'active_support/core_ext/object/blank' require 'active_support/core_ext/string/filters' require 'active_support/core_ext/array/extract_options' module ActionView # = Action View Text Helpers module Helpers #:nodoc: # The TextHelper module provides a set of methods for filtering, formatting # and transforming strings, which can reduce the amount of inline Ruby code in # your views. These helper methods extend Action View making them callable # within your template files. # # ==== Sanitization # # Most text helpers by default sanitize the given content, but do not escape it. # This means HTML tags will appear in the page but all malicious code will be removed. # Let's look at some examples using the +simple_format+ method: # # simple_format('Example') # # => "

Example

" # # simple_format('Example') # # => "

Example

" # # If you want to escape all content, you should invoke the +h+ method before # calling the text helper. # # simple_format h('Example') # # => "

<a href=\"http://example.com/\">Example</a>

" module TextHelper extend ActiveSupport::Concern include SanitizeHelper include TagHelper # The preferred method of outputting text in your views is to use the # <%= "text" %> eRuby syntax. The regular _puts_ and _print_ methods # do not operate as expected in an eRuby code block. If you absolutely must # output text within a non-output code block (i.e., <% %>), you can use the concat method. # # <% # concat "hello" # # is the equivalent of <%= "hello" %> # # if logged_in # concat "Logged in!" # else # concat link_to('login', :action => :login) # end # # will either display "Logged in!" or a login link # %> def concat(string) output_buffer << string end def safe_concat(string) output_buffer.respond_to?(:safe_concat) ? output_buffer.safe_concat(string) : concat(string) end # Truncates a given +text+ after a given :length if +text+ is longer than :length # (defaults to 30). The last characters will be replaced with the :omission (defaults to "...") # for a total length not exceeding :length. # # Pass a :separator to truncate +text+ at a natural break. # # The result is not marked as HTML-safe, so will be subject to the default escaping when # used in views, unless wrapped by raw(). Care should be taken if +text+ contains HTML tags # or entities, because truncation may produce invalid HTML (such as unbalanced or incomplete tags). # # truncate("Once upon a time in a world far far away") # # => "Once upon a time in a world..." # # truncate("Once upon a time in a world far far away", :length => 17) # # => "Once upon a ti..." # # truncate("Once upon a time in a world far far away", :length => 17, :separator => ' ') # # => "Once upon a..." # # truncate("And they found that many people were sleeping better.", :length => 25, :omission => '... (continued)') # # => "And they f... (continued)" # # truncate("

Once upon a time in a world far far away

") # # => "

Once upon a time in a wo..." def truncate(text, options = {}) options.reverse_merge!(:length => 30) text.truncate(options.delete(:length), options) if text end # Highlights one or more +phrases+ everywhere in +text+ by inserting it into # a :highlighter string. The highlighter can be specialized by passing :highlighter # as a single-quoted string with \1 where the phrase is to be inserted (defaults to # '\1') # # highlight('You searched for: rails', 'rails') # # => You searched for: rails # # highlight('You searched for: ruby, rails, dhh', 'actionpack') # # => You searched for: ruby, rails, dhh # # highlight('You searched for: rails', ['for', 'rails'], :highlighter => '\1') # # => You searched for: rails # # highlight('You searched for: rails', 'rails', :highlighter => '\1') # # => You searched for: rails def highlight(text, phrases, options = {}) options[:highlighter] ||= '\1' text = sanitize(text) unless options[:sanitize] == false if text.blank? || phrases.blank? text else match = Array(phrases).map { |p| Regexp.escape(p) }.join('|') text.gsub(/(#{match})(?![^<]*?>)/i, options[:highlighter]) end.html_safe end # Extracts an excerpt from +text+ that matches the first instance of +phrase+. # The :radius option expands the excerpt on each side of the first occurrence of +phrase+ by the number of characters # defined in :radius (which defaults to 100). If the excerpt radius overflows the beginning or end of the +text+, # then the :omission option (which defaults to "...") will be prepended/appended accordingly. The resulting string # will be stripped in any case. If the +phrase+ isn't found, nil is returned. # # excerpt('This is an example', 'an', :radius => 5) # # => ...s is an exam... # # excerpt('This is an example', 'is', :radius => 5) # # => This is a... # # excerpt('This is an example', 'is') # # => This is an example # # excerpt('This next thing is an example', 'ex', :radius => 2) # # => ...next... # # excerpt('This is also an example', 'an', :radius => 8, :omission => ' ') # # => is also an example def excerpt(text, phrase, options = {}) return unless text && phrase radius = options[:radius] || 100 omission = options[:omission] || "..." phrase = Regexp.escape(phrase) return unless found_pos = text =~ /(#{phrase})/i start_pos = [ found_pos - radius, 0 ].max end_pos = [ [ found_pos + phrase.length + radius - 1, 0].max, text.length ].min prefix = start_pos > 0 ? omission : "" postfix = end_pos < text.length - 1 ? omission : "" prefix + text[start_pos..end_pos].strip + postfix end # Attempts to pluralize the +singular+ word unless +count+ is 1. If # +plural+ is supplied, it will use that when count is > 1, otherwise # it will use the Inflector to determine the plural form # # pluralize(1, 'person') # # => 1 person # # pluralize(2, 'person') # # => 2 people # # pluralize(3, 'person', 'users') # # => 3 users # # pluralize(0, 'person') # # => 0 people def pluralize(count, singular, plural = nil) "#{count || 0} " + ((count == 1 || count =~ /^1(\.0+)?$/) ? singular : (plural || singular.pluralize)) end # Wraps the +text+ into lines no longer than +line_width+ width. This method # breaks on the first whitespace character that does not exceed +line_width+ # (which is 80 by default). # # word_wrap('Once upon a time') # # => Once upon a time # # word_wrap('Once upon a time, in a kingdom called Far Far Away, a king fell ill, and finding a successor to the throne turned out to be more trouble than anyone could have imagined...') # # => Once upon a time, in a kingdom called Far Far Away, a king fell ill, and finding\na successor to the throne turned out to be more trouble than anyone could have\nimagined... # # word_wrap('Once upon a time', :line_width => 8) # # => Once\nupon a\ntime # # word_wrap('Once upon a time', :line_width => 1) # # => Once\nupon\na\ntime def word_wrap(text, options = {}) line_width = options[:line_width] || 80 text.split("\n").collect do |line| line.length > line_width ? line.gsub(/(.{1,#{line_width}})(\s+|$)/, "\\1\n").strip : line end * "\n" end # Returns +text+ transformed into HTML using simple formatting rules. # Two or more consecutive newlines(\n\n) are considered as a # paragraph and wrapped in

tags. One newline (\n) is # considered as a linebreak and a
tag is appended. This # method does not remove the newlines from the +text+. # # You can pass any HTML attributes into html_options. These # will be added to all created paragraphs. # # ==== Options # * :sanitize - If +false+, does not sanitize +text+. # * :wrapper_tag - String representing the tag wrapper, defaults to "p" # # ==== Examples # my_text = "Here is some basic text...\n...with a line break." # # simple_format(my_text) # # => "

Here is some basic text...\n
...with a line break.

" # # more_text = "We want to put a paragraph...\n\n...right there." # # simple_format(more_text) # # => "

We want to put a paragraph...

\n\n

...right there.

" # # simple_format("Look ma! A class!", :class => 'description') # # => "

Look ma! A class!

" # # simple_format("I'm allowed! It's true.", {}, :sanitize => false) # # => "

I'm allowed! It's true.

" def simple_format(text, html_options={}, options={}) text = sanitize(text) unless options[:sanitize] == false wrapper_tag = options.fetch(:wrapper_tag, :p) paragraphs = split_paragraphs(text) if paragraphs.empty? content_tag(wrapper_tag, nil, html_options) else paragraphs.map { |paragraph| content_tag(wrapper_tag, paragraph, html_options, options[:sanitize]) }.join("\n\n").html_safe end end # Creates a Cycle object whose _to_s_ method cycles through elements of an # array every time it is called. This can be used for example, to alternate # classes for table rows. You can use named cycles to allow nesting in loops. # Passing a Hash as the last parameter with a :name key will create a # named cycle. The default name for a cycle without a +:name+ key is # "default". You can manually reset a cycle by calling reset_cycle # and passing the name of the cycle. The current cycle string can be obtained # anytime using the current_cycle method. # # # Alternate CSS classes for even and odd numbers... # @items = [1,2,3,4] # # <% @items.each do |item| %> # "> # # # <% end %> #
item
# # # # Cycle CSS classes for rows, and text colors for values within each row # @items = x = [{:first => 'Robert', :middle => 'Daniel', :last => 'James'}, # {:first => 'Emily', :middle => 'Shannon', :maiden => 'Pike', :last => 'Hicks'}, # {:first => 'June', :middle => 'Dae', :last => 'Jones'}] # <% @items.each do |item| %> # "row_class") -%>"> # # <% item.values.each do |value| %> # <%# Create a named cycle "colors" %> # "colors") -%>"> # <%= value %> # # <% end %> # <% reset_cycle("colors") %> # # # <% end %> def cycle(first_value, *values) options = values.extract_options! name = options.fetch(:name, "default") values.unshift(first_value) cycle = get_cycle(name) unless cycle && cycle.values == values cycle = set_cycle(name, Cycle.new(*values)) end cycle.to_s end # Returns the current cycle string after a cycle has been started. Useful # for complex table highlighting or any other design need which requires # the current cycle string in more than one place. # # # Alternate background colors # @items = [1,2,3,4] # <% @items.each do |item| %> #
"> # <%= item %> #
# <% end %> def current_cycle(name = "default") cycle = get_cycle(name) cycle.current_value if cycle end # Resets a cycle so that it starts from the first element the next time # it is called. Pass in +name+ to reset a named cycle. # # # Alternate CSS classes for even and odd numbers... # @items = [[1,2,3,4], [5,6,3], [3,4,5,6,7,4]] # # <% @items.each do |item| %> # "> # <% item.each do |value| %> # "colors") -%>"> # <%= value %> # # <% end %> # # <% reset_cycle("colors") %> # # <% end %> #
def reset_cycle(name = "default") cycle = get_cycle(name) cycle.reset if cycle end class Cycle #:nodoc: attr_reader :values def initialize(first_value, *values) @values = values.unshift(first_value) reset end def reset @index = 0 end def current_value @values[previous_index].to_s end def to_s value = @values[@index].to_s @index = next_index return value end private def next_index step_index(1) end def previous_index step_index(-1) end def step_index(n) (@index + n) % @values.size end end private # The cycle helpers need to store the cycles in a place that is # guaranteed to be reset every time a page is rendered, so it # uses an instance variable of ActionView::Base. def get_cycle(name) @_cycles = Hash.new unless defined?(@_cycles) return @_cycles[name] end def set_cycle(name, cycle_object) @_cycles = Hash.new unless defined?(@_cycles) @_cycles[name] = cycle_object end def split_paragraphs(text) return [] if text.blank? text.to_str.gsub(/\r\n?/, "\n").split(/\n\n+/).map! do |t| t.gsub!(/([^\n]\n)(?=[^\n])/, '\1
') || t end end end end end