Module: Hamlit::HamlHelpers

Extended by:
HamlHelpers
Includes:
XssMods
Included in:
HamlBuffer, HamlHelpers
Defined in:
lib/hamlit/rails_template.rb,
lib/hamlit/parser/haml_helpers.rb,
lib/hamlit/parser/haml_helpers/xss_mods.rb

Overview

This module contains various helpful methods to make it easier to do various tasks. HamlHelpers is automatically included in the context that a Haml template is parsed in, so all these methods are at your disposal from within the template.

Defined Under Namespace

Modules: XssMods Classes: ErrorReturn

Constant Summary collapse

HTML_ESCAPE =

Characters that need to be escaped to HTML entities from user input

{'&' => '&amp;', '<' => '&lt;', '>' => '&gt;', '"' => '&quot;', "'" => '&#39;'}.freeze
HTML_ESCAPE_REGEX = 
/['"><&]/
HTML_ESCAPE_ONCE_REGEX = 
/['"><]|&(?!(?:[a-zA-Z]+|#(?:\d+|[xX][0-9a-fA-F]+));)/
@@action_view_defined = 
false

Class Method Summary collapse

Instance Method Summary collapse

Methods included from XssMods

#capture_haml_with_haml_xss, #escape_once_with_haml_xss, #find_and_preserve_with_haml_xss, #haml_concat_with_haml_xss, #haml_indent_with_haml_xss, #html_escape_with_haml_xss, included, #list_of_with_haml_xss, #precede_with_haml_xss, #preserve_with_haml_xss, #succeed_with_haml_xss, #surround_with_haml_xss

Class Method Details

.action_view? ⇒ Boolean

Returns Whether or not ActionView is loaded.

Returns:

  • (Boolean) —

    Whether or not ActionView is loaded



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# File 'lib/hamlit/parser/haml_helpers.rb', line 56

def self.action_view?
  @@action_view_defined
end

Instance Method Details

#block_is_haml?(block) ⇒ Boolean

Returns whether or not ‘block` is defined directly in a Haml template.

Parameters:

  • block (Proc) —

    A Ruby block

Returns:

  • (Boolean) —

    Whether or not ‘block` is defined directly in a Haml template



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# File 'lib/hamlit/parser/haml_helpers.rb', line 646

def block_is_haml?(block)
  eval('!!defined?(_hamlout)', block.binding)
end

#capture_haml(*args) {|args| ... } ⇒ Object

Captures the result of a block of Haml code, gets rid of the excess indentation, and returns it as a string. For example, after the following,

.foo
  - foo = capture_haml(13) do |a|
    %p= a

the local variable ‘foo` would be assigned to `“<p>13</p>n”`.

Parameters:

  • args (Array) —

    Arguments to pass into the block

Yields:

  • (args) —

    A block of Haml code that will be converted to a string

Yield Parameters:

  • args (Array) —

    ‘args`



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# File 'lib/hamlit/parser/haml_helpers.rb', line 373

def capture_haml(*args, &block)
  buffer = eval('if defined? _hamlout then _hamlout else nil end', block.binding) || haml_buffer
  with_haml_buffer(buffer) do
    position = haml_buffer.buffer.length

    haml_buffer.capture_position = position
    value = block.call(*args)

    captured = haml_buffer.buffer.slice!(position..-1)

    if captured == '' and value != haml_buffer.buffer
      captured = (value.is_a?(String) ? value : nil)
    end

    captured
  end
ensure
  haml_buffer.capture_position = nil
end

#escape_once(text) ⇒ String Also known as: escape_once_without_haml_xss

Escapes HTML entities in ‘text`, but without escaping an ampersand that is already part of an escaped entity.

Parameters:

  • text (String) —

    The string to sanitize

Returns:

  • (String) —

    The sanitized string



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# File 'lib/hamlit/parser/haml_helpers.rb', line 623

def escape_once(text)
  text = text.to_s
  text.gsub(HTML_ESCAPE_ONCE_REGEX, HTML_ESCAPE)
end

#find_and_preserve(input, tags = haml_buffer.options[:preserve]) ⇒ Object #find_and_preserve(tags = haml_buffer.options[:preserve]) { ... } ⇒ Object

Uses #preserve to convert any newlines inside whitespace-sensitive tags into the HTML entities for endlines.

Overloads:

  • #find_and_preserve(input, tags = haml_buffer.options[:preserve]) ⇒ Object

    Escapes newlines within a string.

    Parameters:

    • input (String) —

      The string within which to escape newlines

  • #find_and_preserve(tags = haml_buffer.options[:preserve]) { ... } ⇒ Object

    Escapes newlines within a block of Haml code.

    Yields:

    • The block within which to escape newlines

Parameters:

  • tags (Array<String>) (defaults to: haml_buffer.options[:preserve]) —

    Tags that should have newlines escaped



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# File 'lib/hamlit/parser/haml_helpers.rb', line 111

def find_and_preserve(input = nil, tags = haml_buffer.options[:preserve], &block)
  return find_and_preserve(capture_haml(&block), input || tags) if block
  tags = tags.map { |tag| Regexp.escape(tag) }.join('|')
  re = /<(#{tags})([^>]*)>(.*?)(<\/\1>)/im
  input.to_s.gsub(re) do |s|
    s =~ re # Can't rely on $1, etc. existing since Rails' SafeBuffer#gsub is incompatible
    "<#{$1}#{$2}>#{preserve($3)}</#{$1}>"
  end
end

#haml_concat(text = "") ⇒ Object

Outputs text directly to the Haml buffer, with the proper indentation.

Parameters:

  • text (#to_s) (defaults to: "") —

    The text to output



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# File 'lib/hamlit/parser/haml_helpers.rb', line 396

def haml_concat(text = "")
  haml_internal_concat text
  ErrorReturn.new("haml_concat")
end

#haml_indent ⇒ String

Returns The indentation string for the current line.

Returns:

  • (String) —

    The indentation string for the current line



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# File 'lib/hamlit/parser/haml_helpers.rb', line 427

def haml_indent
  '  ' * haml_buffer.tabulation
end

#haml_tag(name, *rest, attributes = {}) { ... } ⇒ Object #haml_tag(name, text, *flags, attributes = {}) ⇒ Object

Creates an HTML tag with the given name and optionally text and attributes. Can take a block that will run between the opening and closing tags. If the block is a Haml block or outputs text using #haml_concat, the text will be properly indented.

‘name` can be a string using the standard Haml class/id shorthand (e.g. “span#foo.bar”, “#foo”). Just like standard Haml tags, these class and id values will be merged with manually-specified attributes.

‘flags` is a list of symbol flags like those that can be put at the end of a Haml tag (`:/`, `:<`, and `:>`). Currently, only `:/` and `:<` are supported.

‘haml_tag` outputs directly to the buffer; its return value should not be used. If you need to get the results as a string, use #capture_haml.

For example,

haml_tag :table do
  haml_tag :tr do
    haml_tag 'td.cell' do
      haml_tag :strong, "strong!"
      haml_concat "data"
    end
    haml_tag :td do
      haml_concat "more_data"
    end
  end
end

outputs

<table>
  <tr>
    <td class='cell'>
      <strong>
        strong!
      </strong>
      data
    </td>
    <td>
      more_data
    </td>
  </tr>
</table>

Overloads:

  • #haml_tag(name, *rest, attributes = {}) { ... } ⇒ Object

    Yields:

    • The block of Haml code within the tag

  • #haml_tag(name, text, *flags, attributes = {}) ⇒ Object

    Parameters:

    • text (#to_s) —

      The text within the tag

    • flags (Array<Symbol>) —

      Haml end-of-tag flags

Parameters:

  • name (#to_s) —

    The name of the tag



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# File 'lib/hamlit/parser/haml_helpers.rb', line 488

def haml_tag(name, *rest, &block)
  ret = ErrorReturn.new("haml_tag")

  text = rest.shift.to_s unless [Symbol, Hash, NilClass].any? {|t| rest.first.is_a? t}
  flags = []
  flags << rest.shift while rest.first.is_a? Symbol
  attrs = (rest.shift || {})
  attrs.keys.each {|key| attrs[key.to_s] = attrs.delete(key)} unless attrs.empty?
  name, attrs = merge_name_and_attributes(name.to_s, attrs)

  attributes = Hamlit::HamlAttributeBuilder.build_attributes(haml_buffer.html?,
    haml_buffer.options[:attr_wrapper],
    haml_buffer.options[:escape_attrs],
    haml_buffer.options[:hyphenate_data_attrs],
    attrs)

  if text.nil? && block.nil? && (haml_buffer.options[:autoclose].include?(name) || flags.include?(:/))
    haml_internal_concat_raw "<#{name}#{attributes}#{' /' if haml_buffer.options[:format] == :xhtml}>"
    return ret
  end

  if flags.include?(:/)
    raise HamlError.new(HamlError.message(:self_closing_content)) if text
    raise HamlError.new(HamlError.message(:illegal_nesting_self_closing)) if block
  end

  tag = "<#{name}#{attributes}>"
  end_tag = "</#{name}>"
  if block.nil?
    text = text.to_s
    if text.include?("\n")
      haml_internal_concat_raw tag
      tab_up
      haml_internal_concat text
      tab_down
      haml_internal_concat_raw end_tag
    else
      haml_internal_concat_raw tag, false
      haml_internal_concat text, false, false
      haml_internal_concat_raw end_tag, true, false
    end
    return ret
  end

  if text
    raise HamlError.new(HamlError.message(:illegal_nesting_line, name))
  end

  if flags.include?(:<)
    haml_internal_concat_raw tag, false
    haml_internal_concat "#{capture_haml(&block).strip}", false, false
    haml_internal_concat_raw end_tag, true, false
    return ret
  end

  haml_internal_concat_raw tag
  tab_up
  block.call
  tab_down
  haml_internal_concat_raw end_tag

  ret
end

#haml_tag_if(condition, *tag) ⇒ Object

Conditionally wrap a block in an element. If ‘condition` is `true` then this method renders the tag described by the arguments in `tag` (using #haml_tag) with the given block inside, otherwise it just renders the block.

For example,

- haml_tag_if important, '.important' do
  %p
    A (possibly) important paragraph.

will produce

<div class='important'>
  <p>
    A (possibly) important paragraph.
  </p>
</div>

if ‘important` is truthy, and just

<p>
  A (possibly) important paragraph.
</p>

otherwise.

Like #haml_tag, ‘haml_tag_if` outputs directly to the buffer and its return value should not be used. Use #capture_haml if you need to use its results as a string.

Parameters:

  • condition —

    The condition to test to determine whether to render the enclosing tag

  • tag —

    Definition of the enclosing tag. See #haml_tag for details (specifically the form that takes a block)



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# File 'lib/hamlit/parser/haml_helpers.rb', line 586

def haml_tag_if(condition, *tag)
  if condition
    haml_tag(*tag){ yield }
  else
    yield
  end
  ErrorReturn.new("haml_tag_if")
end

#html_attrs(lang = 'en-US') ⇒ {#to_s => String}

Returns a hash containing default assignments for the ‘xmlns`, `lang`, and `xml:lang` attributes of the `html` HTML element. For example,

%html{html_attrs}

becomes

<html xmlns='http://www.w3.org/1999/xhtml' xml:lang='en-US' lang='en-US'>

Parameters:

  • lang (String) (defaults to: 'en-US') —

    The value of ‘xml:lang` and `lang`

Returns:

  • ({#to_s => String}) —

    The attribute hash



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# File 'lib/hamlit/parser/haml_helpers.rb', line 228

def html_attrs(lang = 'en-US')
  if haml_buffer.options[:format] == :xhtml
    {:xmlns => "http://www.w3.org/1999/xhtml", 'xml:lang' => lang, :lang => lang}
  else
    {:lang => lang}
  end
end

#html_escape(text) ⇒ String Also known as: html_escape_without_haml_xss

Returns a copy of ‘text` with ampersands, angle brackets and quotes escaped into HTML entities.

Note that if ActionView is loaded and XSS protection is enabled (as is the default for Rails 3.0+, and optional for version 2.3.5+), this won’t escape text declared as “safe”.

Parameters:

  • text (String) —

    The string to sanitize

Returns:

  • (String) —

    The sanitized string



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# File 'lib/hamlit/parser/haml_helpers.rb', line 609

def html_escape(text)
  CGI.escapeHTML(text.to_s)
end

#init_haml_helpers ⇒ Object

Note: this does not need to be called when using Haml helpers normally in Rails.

Initializes the current object as though it were in the same context as a normal ActionView instance using Haml. This is useful if you want to use the helpers in a context other than the normal setup with ActionView. For example:

context = Object.new
class << context
  include Hamlit::HamlHelpers
end
context.init_haml_helpers
context.haml_tag :p, "Stuff"



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# File 'lib/hamlit/parser/haml_helpers.rb', line 76

def init_haml_helpers
  @haml_buffer = Hamlit::HamlBuffer.new(haml_buffer, HamlOptions.new.for_buffer)
  nil
end

#is_haml? ⇒ Boolean

Returns whether or not the current template is a Haml template.

This function, unlike other Hamlit::HamlHelpers functions, also works in other ‘ActionView` templates, where it will always return false.

Returns:

  • (Boolean) —

    Whether or not the current template is a Haml template



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# File 'lib/hamlit/parser/haml_helpers.rb', line 638

def is_haml?
  !@haml_buffer.nil? && @haml_buffer.active?
end

#list_of(enum, opts = {}) {|item| ... } ⇒ Object

Takes an ‘Enumerable` object and a block and iterates over the enum, yielding each element to a Haml block and putting the result into `<li>` elements. This creates a list of the results of the block. For example:

= list_of([['hello'], ['yall']]) do |i|
  = i[0]

Produces:

<li>hello</li>
<li>yall</li>

And:

= list_of({:title => 'All the stuff', :description => 'A book about all the stuff.'}) do |key, val|
  %h3= key.humanize
  %p= val

Produces:

<li>
  <h3>Title</h3>
  <p>All the stuff</p>
</li>
<li>
  <h3>Description</h3>
  <p>A book about all the stuff.</p>
</li>

While:

= list_of(["Home", "About", "Contact", "FAQ"], {class: "nav", role: "nav"}) do |item|
  %a{ href="#" }= item

Produces:

   <li class='nav' role='nav'>
     <a href='#'>Home</a>
   </li>
   <li class='nav' role='nav'>
     <a href='#'>About</a>
   </li>
   <li class='nav' role='nav'>
     <a href='#'>Contact</a>
   </li>
   <li class='nav' role='nav'>
     <a href='#'>FAQ</a>
   </li>

`[[class", "nav"], [role", "nav"]]` could have been used instead of `{class: "nav", role: "nav"}` (or any enumerable collection where each pair of items responds to #to_s)

Parameters:

  • enum (Enumerable) —

    The list of objects to iterate over

  • opts (Enumerable<#to_s,#to_s>) (defaults to: {}) —

    Each key/value pair will become an attribute pair for each list item element.

Yields:

  • (item) —

    A block which contains Haml code that goes within list items

Yield Parameters:

  • item —

    An element of ‘enum`



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# File 'lib/hamlit/parser/haml_helpers.rb', line 200

def list_of(enum, opts={}, &block)
  opts_attributes = opts.map { |k, v| " #{k}='#{v}'" }.join
  enum.map do |i|
    result = capture_haml(i, &block)

    if result.count("\n") > 1
      result.gsub!("\n", "\n  ")
      result = "\n  #{result.strip}\n"
    else
      result.strip!
    end

    %Q!<li#{opts_attributes}>#{result}</li>!
  end.join("\n")
end

#non_haml { ... } ⇒ Object

Runs a block of code in a non-Haml context (i.e. #is_haml? will return false).

This is mainly useful for rendering sub-templates such as partials in a non-Haml language, particularly where helpers may behave differently when run from Haml.

Note that this is automatically applied to Rails partials.

Yields:

  • A block which won’t register as Haml



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# File 'lib/hamlit/parser/haml_helpers.rb', line 90

def non_haml
  was_active = @haml_buffer.active?
  @haml_buffer.active = false
  yield
ensure
  @haml_buffer.active = was_active
end

#precede(str) { ... } ⇒ Object

Prepends a string to the beginning of a Haml block, with no whitespace between. For example:

= precede '*' do
  %span.small Not really

Produces:

*<span class='small'>Not really</span>

Parameters:

  • str (String) —

    The string to add before the Haml

Yields:

  • A block of Haml to prepend to



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# File 'lib/hamlit/parser/haml_helpers.rb', line 336

def precede(str, &block)
  "#{str}#{capture_haml(&block).chomp}\n"
end

#preserve(input) ⇒ Object #preserve { ... } ⇒ Object Also known as: flatten

Takes any string, finds all the newlines, and converts them to HTML entities so they’ll render correctly in whitespace-sensitive tags without screwing up the indentation.

Overloads:

  • #preserve(input) ⇒ Object

    Escapes newlines within a string.

    Parameters:

    • input (String) —

      The string within which to escape all newlines

  • #preserve { ... } ⇒ Object

    Escapes newlines within a block of Haml code.

    Yields:

    • The block within which to escape newlines



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# File 'lib/hamlit/parser/haml_helpers.rb', line 133

def preserve(input = nil, &block)
  return preserve(capture_haml(&block)) if block
  s = input.to_s.chomp("\n")
  s.gsub!(/\n/, '&#x000A;')
  s.delete!("\r")
  s
end

#succeed(str) { ... } ⇒ Object

Appends a string to the end of a Haml block, with no whitespace between. For example:

click
= succeed '.' do
  %a{:href=>"thing"} here

Produces:

click
<a href='thing'>here</a>.

Parameters:

  • str (String) —

    The string to add after the Haml

Yields:

  • A block of Haml to append to



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# File 'lib/hamlit/parser/haml_helpers.rb', line 355

def succeed(str, &block)
  "#{capture_haml(&block).chomp}#{str}\n"
end

#surround(front, back = front) { ... } ⇒ Object

Surrounds a block of Haml code with strings, with no whitespace in between. For example:

= surround '(', ')' do
  %a{:href => "food"} chicken

Produces:

(<a href='food'>chicken</a>)

and

= surround '*' do
  %strong angry

Produces:

*<strong>angry</strong>*

Parameters:

  • front (String) —

    The string to add before the Haml

  • back (String) (defaults to: front) —

    The string to add after the Haml

Yields:

  • A block of Haml to surround



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# File 'lib/hamlit/parser/haml_helpers.rb', line 317

def surround(front, back = front, &block)
  output = capture_haml(&block)

  "#{front}#{output.chomp}#{back}\n"
end

#tab_down(i = 1) ⇒ Object

Decrements the number of tabs the buffer automatically adds to the lines of the template.

Parameters:

  • i (Fixnum) (defaults to: 1) —

    The number of tabs by which to decrease the indentation

See Also:



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# File 'lib/hamlit/parser/haml_helpers.rb', line 263

def tab_down(i = 1)
  haml_buffer.tabulation -= i
end

#tab_up(i = 1) ⇒ Object

Increments the number of tabs the buffer automatically adds to the lines of the template. For example:

%h1 foo
- tab_up
%p bar
- tab_down
%strong baz

Produces:

<h1>foo</h1>
  <p>bar</p>
<strong>baz</strong>

Parameters:

  • i (Fixnum) (defaults to: 1) —

    The number of tabs by which to increase the indentation

See Also:



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# File 'lib/hamlit/parser/haml_helpers.rb', line 254

def tab_up(i = 1)
  haml_buffer.tabulation += i
end

#with_tabs(i) { ... } ⇒ Object

Sets the number of tabs the buffer automatically adds to the lines of the template, but only for the duration of the block. For example:

%h1 foo
- with_tabs(2) do
  %p bar
%strong baz

Produces:

<h1>foo</h1>
    <p>bar</p>
<strong>baz</strong>

Parameters:

  • i (Fixnum) —

    The number of tabs to use

Yields:

  • A block in which the indentation will be ‘i` spaces



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# File 'lib/hamlit/parser/haml_helpers.rb', line 286

def with_tabs(i)
  old_tabs = haml_buffer.tabulation
  haml_buffer.tabulation = i
  yield
ensure
  haml_buffer.tabulation = old_tabs
end