/actionpack/lib/action_view/helpers/text_helper.rb
Ruby | 417 lines | 135 code | 31 blank | 251 comment | 16 complexity | 82eec261940cc73c4a0e912340604bc9 MD5 | raw file
- require 'active_support/core_ext/object/blank'
- require 'active_support/core_ext/string/filters'
- require 'action_view/helpers/tag_helper'
- 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('<a href="http://example.com/">Example</a>')
- # # => "<p><a href=\"http://example.com/\">Example</a></p>"
- #
- # simple_format('<a href="javascript:alert(\'no!\')">Example</a>')
- # # => "<p><a>Example</a></p>"
- #
- # If you want to escape all content, you should invoke the +h+ method before
- # calling the text helper.
- #
- # simple_format h('<a href="http://example.com/">Example</a>')
- # # => "<p><a href=\"http://example.com/\">Example</a></p>"
- module TextHelper
- extend ActiveSupport::Concern
- include SanitizeHelper
- # 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.
- #
- # ==== Examples
- # <%
- # 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 <tt>:length</tt> if +text+ is longer than <tt>:length</tt>
- # (defaults to 30). The last characters will be replaced with the <tt>:omission</tt> (defaults to "...")
- # for a total length not exceeding <tt>:length</tt>.
- #
- # Pass a <tt>:separator</tt> 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 <tt>raw()</tt>. Care should be taken if +text+ contains HTML tags
- # or entities, because truncation may produce invalid HTML (such as unbalanced or incomplete tags).
- #
- # ==== Examples
- #
- # 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("<p>Once upon a time in a world far far away</p>")
- # # => "<p>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 <tt>:highlighter</tt> string. The highlighter can be specialized by passing <tt>:highlighter</tt>
- # as a single-quoted string with \1 where the phrase is to be inserted (defaults to
- # '<strong class="highlight">\1</strong>')
- #
- # ==== Examples
- # highlight('You searched for: rails', 'rails')
- # # => You searched for: <strong class="highlight">rails</strong>
- #
- # highlight('You searched for: ruby, rails, dhh', 'actionpack')
- # # => You searched for: ruby, rails, dhh
- #
- # highlight('You searched for: rails', ['for', 'rails'], :highlighter => '<em>\1</em>')
- # # => You searched <em>for</em>: <em>rails</em>
- #
- # highlight('You searched for: rails', 'rails', :highlighter => '<a href="search?q=\1">\1</a>')
- # # => You searched for: <a href="search?q=rails">rails</a>
- #
- # You can still use <tt>highlight</tt> with the old API that accepts the
- # +highlighter+ as its optional third parameter:
- # highlight('You searched for: rails', 'rails', '<a href="search?q=\1">\1</a>') # => You searched for: <a href="search?q=rails">rails</a>
- def highlight(text, phrases, *args)
- options = args.extract_options!
- unless args.empty?
- options[:highlighter] = args[0] || '<strong class="highlight">\1</strong>'
- end
- options.reverse_merge!(:highlighter => '<strong class="highlight">\1</strong>')
- 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 <tt>:radius</tt> option expands the excerpt on each side of the first occurrence of +phrase+ by the number of characters
- # defined in <tt>:radius</tt> (which defaults to 100). If the excerpt radius overflows the beginning or end of the +text+,
- # then the <tt>:omission</tt> 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.
- #
- # ==== Examples
- # 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 => '<chop> ')
- # # => <chop> is also an example
- #
- # You can still use <tt>excerpt</tt> with the old API that accepts the
- # +radius+ as its optional third and the +ellipsis+ as its
- # optional forth parameter:
- # excerpt('This is an example', 'an', 5) # => ...s is an exam...
- # excerpt('This is also an example', 'an', 8, '<chop> ') # => <chop> is also an example
- def excerpt(text, phrase, *args)
- return unless text && phrase
- options = args.extract_options!
- unless args.empty?
- options[:radius] = args[0] || 100
- options[:omission] = args[1] || "..."
- end
- options.reverse_merge!(:radius => 100, :omission => "...")
- phrase = Regexp.escape(phrase)
- return unless found_pos = text.mb_chars =~ /(#{phrase})/i
- start_pos = [ found_pos - options[:radius], 0 ].max
- end_pos = [ [ found_pos + phrase.mb_chars.length + options[:radius] - 1, 0].max, text.mb_chars.length ].min
- prefix = start_pos > 0 ? options[:omission] : ""
- postfix = end_pos < text.mb_chars.length - 1 ? options[:omission] : ""
- prefix + text.mb_chars[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
- #
- # ==== Examples
- # 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+)?$/) ? singular : (plural || singular.pluralize))
- end
- # Wraps the +text+ into lines no longer than +line_width+ width. This method
- # breaks on the first whitespace character that does not exceed +line_width+
- # (which is 80 by default).
- #
- # ==== Examples
- #
- # word_wrap('Once upon a time')
- # # => Once upon a time
- #
- # word_wrap('Once upon a time, in a kingdom called Far Far Away, a king fell ill, and finding a successor to the throne turned out to be more trouble than anyone could have imagined...')
- # # => Once upon a time, in a kingdom called Far Far Away, a king fell ill, and finding\n a successor to the throne turned out to be more trouble than anyone could have\n imagined...
- #
- # word_wrap('Once upon a time', :line_width => 8)
- # # => Once upon\na time
- #
- # word_wrap('Once upon a time', :line_width => 1)
- # # => Once\nupon\na\ntime
- #
- # You can still use <tt>word_wrap</tt> with the old API that accepts the
- # +line_width+ as its optional second parameter:
- # word_wrap('Once upon a time', 8) # => Once upon\na time
- def word_wrap(text, *args)
- options = args.extract_options!
- unless args.blank?
- options[:line_width] = args[0] || 80
- end
- options.reverse_merge!(:line_width => 80)
- text.split("\n").collect do |line|
- line.length > options[:line_width] ? line.gsub(/(.{1,#{options[:line_width]}})(\s+|$)/, "\\1\n").strip : line
- end * "\n"
- end
- # Returns +text+ transformed into HTML using simple formatting rules.
- # Two or more consecutive newlines(<tt>\n\n</tt>) are considered as a
- # paragraph and wrapped in <tt><p></tt> tags. One newline (<tt>\n</tt>) is
- # considered as a linebreak and a <tt><br /></tt> tag is appended. This
- # method does not remove the newlines from the +text+.
- #
- # You can pass any HTML attributes into <tt>html_options</tt>. These
- # will be added to all created paragraphs.
- #
- # ==== Options
- # * <tt>:sanitize</tt> - If +false+, does not sanitize +text+.
- #
- # ==== Examples
- # my_text = "Here is some basic text...\n...with a line break."
- #
- # simple_format(my_text)
- # # => "<p>Here is some basic text...\n<br />...with a line break.</p>"
- #
- # more_text = "We want to put a paragraph...\n\n...right there."
- #
- # simple_format(more_text)
- # # => "<p>We want to put a paragraph...</p>\n\n<p>...right there.</p>"
- #
- # simple_format("Look ma! A class!", :class => 'description')
- # # => "<p class='description'>Look ma! A class!</p>"
- #
- # simple_format("<span>I'm allowed!</span> It's true.", {}, :sanitize => false)
- # # => "<p><span>I'm allowed!</span> It's true.</p>"
- def simple_format(text, html_options={}, options={})
- text = '' if text.nil?
- text = text.dup
- start_tag = tag('p', html_options, true)
- text = sanitize(text) unless options[:sanitize] == false
- text = text.to_str
- text.gsub!(/\r\n?/, "\n") # \r\n and \r -> \n
- text.gsub!(/\n\n+/, "</p>\n\n#{start_tag}") # 2+ newline -> paragraph
- text.gsub!(/([^\n]\n)(?=[^\n])/, '\1<br />') # 1 newline -> br
- text.insert 0, start_tag
- text.html_safe.safe_concat("</p>")
- 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 <tt>:name</tt> key will create a
- # named cycle. The default name for a cycle without a +:name+ key is
- # <tt>"default"</tt>. 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.
- #
- # ==== Examples
- # # Alternate CSS classes for even and odd numbers...
- # @items = [1,2,3,4]
- # <table>
- # <% @items.each do |item| %>
- # <tr class="<%= cycle("odd", "even") -%>">
- # <td>item</td>
- # </tr>
- # <% end %>
- # </table>
- #
- #
- # # 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| %>
- # <tr class="<%= cycle("odd", "even", :name => "row_class") -%>">
- # <td>
- # <% item.values.each do |value| %>
- # <%# Create a named cycle "colors" %>
- # <span style="color:<%= cycle("red", "green", "blue", :name => "colors") -%>">
- # <%= value %>
- # </span>
- # <% end %>
- # <% reset_cycle("colors") %>
- # </td>
- # </tr>
- # <% end %>
- def cycle(first_value, *values)
- if (values.last.instance_of? Hash)
- params = values.pop
- name = params[:name]
- else
- name = "default"
- end
- 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.
- #
- # ==== Example
- # # Alternate background colors
- # @items = [1,2,3,4]
- # <% @items.each do |item| %>
- # <div style="background-color:<%= cycle("red","white","blue") %>">
- # <span style="background-color:<%= current_cycle %>"><%= item %></span>
- # </div>
- # <% 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.
- #
- # ==== Example
- # # Alternate CSS classes for even and odd numbers...
- # @items = [[1,2,3,4], [5,6,3], [3,4,5,6,7,4]]
- # <table>
- # <% @items.each do |item| %>
- # <tr class="<%= cycle("even", "odd") -%>">
- # <% item.each do |value| %>
- # <span style="color:<%= cycle("#333", "#666", "#999", :name => "colors") -%>">
- # <%= value %>
- # </span>
- # <% end %>
- #
- # <% reset_cycle("colors") %>
- # </tr>
- # <% end %>
- # </table>
- 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
- end
- end
- end