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rails--rails/actionpack/lib/action_view/helpers/text_helper.rb
Jeremy Kemper 71234daef1 r4487@asus: jeremy | 2006-04-29 12:21:39 -0700
Check whether @flash is defined? for warnings-safety.
 r4488@asus:  jeremy | 2006-04-29 12:23:15 -0700
 Check whether @flash is defined? for warnings-safety. Obviates nil? check.
 r4489@asus:  jeremy | 2006-04-29 12:45:18 -0700
 Check whether @session is defined? for warnings-safety.
 r4490@asus:  jeremy | 2006-04-29 12:50:41 -0700
 Check whether @rendering_runtime is defined? for warnings-safety.
 r4491@asus:  jeremy | 2006-04-29 12:55:01 -0700
 Check whether @_cycles is defined? for warnings-safety.
 r4492@asus:  jeremy | 2006-04-29 12:59:19 -0700
 Check whether instance variables are defined? for warnings-safety.
 r4493@asus:  jeremy | 2006-04-29 13:14:09 -0700
 Add nil @template to PrototypeHelperTest to suppress unitialized instance variable warning.
 r4494@asus:  jeremy | 2006-04-29 13:31:34 -0700
 Check whether @auto_index defined? for warnings-safety.
 r4495@asus:  jeremy | 2006-04-29 13:32:24 -0700
 Wrap content_columns redefinitions with silence_warnings.
 r4496@asus:  jeremy | 2006-04-29 13:35:28 -0700
 Wrap more redefinitions with silence_warnings.
 r4829@asus:  jeremy | 2006-07-08 10:59:20 -0700
 abstract unit, fix warnings
 r4830@asus:  jeremy | 2006-07-08 11:06:12 -0700
 Use parens to silence warning.
 r4831@asus:  jeremy | 2006-07-08 11:06:48 -0700
 Use parens to silence warning.


git-svn-id: http://svn-commit.rubyonrails.org/rails/trunk@4595 5ecf4fe2-1ee6-0310-87b1-e25e094e27de
2006-07-08 18:14:49 +00:00

368 lines
14 KiB
Ruby

require File.dirname(__FILE__) + '/tag_helper'
module ActionView
module Helpers #:nodoc:
# Provides a set of methods for working with text strings that can help unburden the level of inline Ruby code in the
# templates. In the example below we iterate over a collection of posts provided to the template and print each title
# after making sure it doesn't run longer than 20 characters:
# <% for post in @posts %>
# Title: <%= truncate(post.title, 20) %>
# <% end %>
module TextHelper
# The regular puts and print are outlawed in eRuby. It's recommended to use the <%= "hello" %> form instead of print "hello".
# If you absolutely must use a method-based output, you can use concat. It's used like this: <% concat "hello", binding %>. Notice that
# it doesn't have an equal sign in front. Using <%= concat "hello" %> would result in a double hello.
def concat(string, binding)
eval("_erbout", binding).concat(string)
end
# Truncates +text+ to the length of +length+ and replaces the last three characters with the +truncate_string+
# if the +text+ is longer than +length+.
def truncate(text, length = 30, truncate_string = "...")
if text.nil? then return end
l = length - truncate_string.length
if $KCODE == "NONE"
text.length > length ? text[0...l] + truncate_string : text
else
chars = text.split(//)
chars.length > length ? chars[0...l].join + truncate_string : text
end
end
# Highlights the +phrase+ where it is found in the +text+ by surrounding it like
# <strong class="highlight">I'm a highlight phrase</strong>. The highlighter can be specialized by
# passing +highlighter+ as single-quoted string with \1 where the phrase is supposed to be inserted.
# N.B.: The +phrase+ is sanitized to include only letters, digits, and spaces before use.
def highlight(text, phrase, highlighter = '<strong class="highlight">\1</strong>')
if phrase.blank? then return text end
text.gsub(/(#{Regexp.escape(phrase)})/i, highlighter) unless text.nil?
end
# Extracts an excerpt from the +text+ surrounding the +phrase+ with a number of characters on each side determined
# by +radius+. If the phrase isn't found, nil is returned. Ex:
# excerpt("hello my world", "my", 3) => "...lo my wo..."
def excerpt(text, phrase, radius = 100, excerpt_string = "...")
if text.nil? || phrase.nil? then return end
phrase = Regexp.escape(phrase)
if found_pos = text =~ /(#{phrase})/i
start_pos = [ found_pos - radius, 0 ].max
end_pos = [ found_pos + phrase.length + radius, text.length ].min
prefix = start_pos > 0 ? excerpt_string : ""
postfix = end_pos < text.length ? excerpt_string : ""
prefix + text[start_pos..end_pos].strip + postfix
else
nil
end
end
# Attempts to pluralize the +singular+ word unless +count+ is 1. See source for pluralization rules.
def pluralize(count, singular, plural = nil)
"#{count} " + if count == 1
singular
elsif plural
plural
elsif Object.const_defined?("Inflector")
Inflector.pluralize(singular)
else
singular + "s"
end
end
# Word wrap long lines to line_width.
def word_wrap(text, line_width = 80)
text.gsub(/\n/, "\n\n").gsub(/(.{1,#{line_width}})(\s+|$)/, "\\1\n").strip
end
begin
require_library_or_gem "redcloth" unless Object.const_defined?(:RedCloth)
# Returns the text with all the Textile codes turned into HTML-tags.
# <i>This method is only available if RedCloth can be required</i>.
def textilize(text)
if text.blank?
""
else
textilized = RedCloth.new(text, [ :hard_breaks ])
textilized.hard_breaks = true if textilized.respond_to?("hard_breaks=")
textilized.to_html
end
end
# Returns the text with all the Textile codes turned into HTML-tags, but without the regular bounding <p> tag.
# <i>This method is only available if RedCloth can be required</i>.
def textilize_without_paragraph(text)
textiled = textilize(text)
if textiled[0..2] == "<p>" then textiled = textiled[3..-1] end
if textiled[-4..-1] == "</p>" then textiled = textiled[0..-5] end
return textiled
end
rescue LoadError
# We can't really help what's not there
end
begin
require_library_or_gem "bluecloth" unless Object.const_defined?(:BlueCloth)
# Returns the text with all the Markdown codes turned into HTML-tags.
# <i>This method is only available if BlueCloth can be required</i>.
def markdown(text)
text.blank? ? "" : BlueCloth.new(text).to_html
end
rescue LoadError
# We can't really help what's not there
end
# Returns +text+ transformed into HTML using very simple formatting rules
# Surrounds paragraphs with <tt><p></tt> tags, and converts line breaks into <tt><br/></tt>
# Two consecutive newlines(<tt>\n\n</tt>) are considered as a paragraph, one newline (<tt>\n</tt>) is
# considered a linebreak, three or more consecutive newlines are turned into two newlines
def simple_format(text)
text.gsub!(/(\r\n|\n|\r)/, "\n") # lets make them newlines crossplatform
text.gsub!(/\n\n+/, "\n\n") # zap dupes
text.gsub!(/\n\n/, '</p>\0<p>') # turn two newlines into paragraph
text.gsub!(/([^\n])(\n)([^\n])/, '\1\2<br />\3') # turn single newline into <br />
content_tag("p", text)
end
# Turns all urls and email addresses into clickable links. The +link+ parameter can limit what should be linked.
# Options are <tt>:all</tt> (default), <tt>:email_addresses</tt>, and <tt>:urls</tt>.
#
# Example:
# auto_link("Go to http://www.rubyonrails.com and say hello to david@loudthinking.com") =>
# Go to <a href="http://www.rubyonrails.com">http://www.rubyonrails.com</a> and
# say hello to <a href="mailto:david@loudthinking.com">david@loudthinking.com</a>
#
# If a block is given, each url and email address is yielded and the
# result is used as the link text. Example:
# auto_link(post.body, :all, :target => '_blank') do |text|
# truncate(text, 15)
# end
def auto_link(text, link = :all, href_options = {}, &block)
return '' if text.blank?
case link
when :all then auto_link_urls(auto_link_email_addresses(text, &block), href_options, &block)
when :email_addresses then auto_link_email_addresses(text, &block)
when :urls then auto_link_urls(text, href_options, &block)
end
end
# Turns all links into words, like "<a href="something">else</a>" to "else".
def strip_links(text)
text.gsub(/<a\b.*?>(.*?)<\/a>/m, '\1')
end
# Try to require the html-scanner library
begin
require 'html/tokenizer'
require 'html/node'
rescue LoadError
# if there isn't a copy installed, use the vendor version in
# action controller
$:.unshift File.join(File.dirname(__FILE__), "..", "..",
"action_controller", "vendor", "html-scanner")
require 'html/tokenizer'
require 'html/node'
end
VERBOTEN_TAGS = %w(form script) unless defined?(VERBOTEN_TAGS)
VERBOTEN_ATTRS = /^on/i unless defined?(VERBOTEN_ATTRS)
# Sanitizes the given HTML by making form and script tags into regular
# text, and removing all "onxxx" attributes (so that arbitrary Javascript
# cannot be executed). Also removes href attributes that start with
# "javascript:".
#
# Returns the sanitized text.
def sanitize(html)
# only do this if absolutely necessary
if html.index("<")
tokenizer = HTML::Tokenizer.new(html)
new_text = ""
while token = tokenizer.next
node = HTML::Node.parse(nil, 0, 0, token, false)
new_text << case node
when HTML::Tag
if VERBOTEN_TAGS.include?(node.name)
node.to_s.gsub(/</, "&lt;")
else
if node.closing != :close
node.attributes.delete_if { |attr,v| attr =~ VERBOTEN_ATTRS }
if node.attributes["href"] =~ /^javascript:/i
node.attributes.delete "href"
end
end
node.to_s
end
else
node.to_s.gsub(/</, "&lt;")
end
end
html = new_text
end
html
end
# Strips all HTML tags from the input, including comments. This uses the html-scanner
# tokenizer and so it's HTML parsing ability is limited by that of html-scanner.
#
# Returns the tag free text.
def strip_tags(html)
if html.index("<")
text = ""
tokenizer = HTML::Tokenizer.new(html)
while token = tokenizer.next
node = HTML::Node.parse(nil, 0, 0, token, false)
# result is only the content of any Text nodes
text << node.to_s if node.class == HTML::Text
end
# strip any comments, and if they have a newline at the end (ie. line with
# only a comment) strip that too
text.gsub(/<!--(.*?)-->[\n]?/m, "")
else
html # already plain text
end
end
# Returns a Cycle object whose to_s value cycles through items of an
# array every time it is called. This can be used to alternate classes
# for table rows:
#
# <%- for item in @items do -%>
# <tr class="<%= cycle("even", "odd") %>">
# ... use item ...
# </tr>
# <%- end -%>
#
# You can use named cycles to prevent clashes in nested loops. You'll
# have to reset the inner cycle, manually:
#
# <%- for item in @items do -%>
# <tr class="<%= cycle("even", "odd", :name => "row_class")
# <td>
# <%- for value in item.values do -%>
# <span style="color:'<%= cycle("red", "green", "blue"
# :name => "colors") %>'">
# item
# </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)
if (cycle.nil? || cycle.values != values)
cycle = set_cycle(name, Cycle.new(*values))
end
return cycle.to_s
end
# Resets a cycle so that it starts from the first element in the array
# the next time it is used.
def reset_cycle(name = "default")
cycle = get_cycle(name)
cycle.reset unless cycle.nil?
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 to_s
value = @values[@index].to_s
@index = (@index + 1) % @values.size
return value
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
AUTO_LINK_RE = /
( # leading text
<\w+.*?>| # leading HTML tag, or
[^=!:'"\/]| # leading punctuation, or
^ # beginning of line
)
(
(?:http[s]?:\/\/)| # protocol spec, or
(?:www\.) # www.*
)
(
([\w]+:?[=?&\/.-]?)* # url segment
\w+[\/]? # url tail
(?:\#\w*)? # trailing anchor
)
([[:punct:]]|\s|<|$) # trailing text
/x unless const_defined?(:AUTO_LINK_RE)
# Turns all urls into clickable links. If a block is given, each url
# is yielded and the result is used as the link text. Example:
# auto_link_urls(post.body, :all, :target => '_blank') do |text|
# truncate(text, 15)
# end
def auto_link_urls(text, href_options = {})
extra_options = tag_options(href_options.stringify_keys) || ""
text.gsub(AUTO_LINK_RE) do
all, a, b, c, d = $&, $1, $2, $3, $5
if a =~ /<a\s/i # don't replace URL's that are already linked
all
else
text = b + c
text = yield(text) if block_given?
%(#{a}<a href="#{b=="www."?"http://www.":b}#{c}"#{extra_options}>#{text}</a>#{d})
end
end
end
# Turns all email addresses into clickable links. If a block is given,
# each email is yielded and the result is used as the link text.
# Example:
# auto_link_email_addresses(post.body) do |text|
# truncate(text, 15)
# end
def auto_link_email_addresses(text)
text.gsub(/([\w\.!#\$%\-+.]+@[A-Za-z0-9\-]+(\.[A-Za-z0-9\-]+)+)/) do
text = $1
text = yield(text) if block_given?
%{<a href="mailto:#{$1}">#{text}</a>}
end
end
end
end
end