module Sass::Util

A module containing various useful functions.

Constants

ATOMIC_WRITE_MUTEX

@private

BASE64_DIGITS
BASE64_DIGIT_MAP
CHARSET_REGEXP
MultibyteStringScanner

rubocop:disable ConstantName

RUBY_ENGINE

The Ruby engine we're running under. Defaults to `“ruby”` if the top-level constant is undefined. @api public

RUBY_VERSION_COMPONENTS

An array of ints representing the Ruby version number. @api public

URI_ESCAPE

This is a hack around the fact that you can't instantiate a URI parser on 1.8, so we have to have this hacky stuff to work around it. When 1.8 support is dropped, we can remove this method.

@private

UTF_16BE_BOM
UTF_16LE_BOM
UTF_8_BOM
VLQ_BASE
VLQ_BASE_MASK
VLQ_BASE_SHIFT
VLQ_CONTINUATION_BIT

Public Instance Methods

absolute_path(path, dir_string = nil) click to toggle source

A cross-platform implementation of `File.absolute_path`.

@param path [String] @param dir_string [String] The directory to consider [path] relative to. @return [String] The absolute version of `path`.

# File lib/sass/util.rb, line 1179
def absolute_path(path, dir_string = nil)
  # Ruby 1.8 doesn't support File.absolute_path.
  return File.absolute_path(path, dir_string) unless ruby1_8?

  # File.expand_path expands "~", which we don't want.
  return File.expand_path(path, dir_string) unless path[0] == ?~
  File.expand_path(File.join(".", path), dir_string)
end
abstract(obj) click to toggle source

Throws a NotImplementedError for an abstract method.

@param obj [Object] `self` @raise [NotImplementedError]

# File lib/sass/util.rb, line 473
def abstract(obj)
  raise NotImplementedError.new("#{obj.class} must implement ##{caller_info[2]}")
end
ap_geq?(version) click to toggle source

Returns whether this environment is using ActionPack of a version greater than or equal to that specified.

@param version [String] The string version number to check against.

Should be greater than or equal to Rails 3,
because otherwise ActionPack::VERSION isn't autoloaded

@return [Boolean]

# File lib/sass/util.rb, line 558
def ap_geq?(version)
  # The ActionPack module is always loaded automatically in Rails >= 3
  return false unless defined?(ActionPack) && defined?(ActionPack::VERSION) &&
    defined?(ActionPack::VERSION::STRING)

  version_geq(ActionPack::VERSION::STRING, version)
end
ap_geq_3?() click to toggle source

Returns whether this environment is using ActionPack version 3.0.0 or greater.

@return [Boolean]

# File lib/sass/util.rb, line 547
def ap_geq_3?
  ap_geq?("3.0.0.beta1")
end
array_minus(minuend, subtrahend) click to toggle source

Returns a sub-array of `minuend` containing only elements that are also in `subtrahend`. Ensures that the return value has the same order as `minuend`, even on Rubinius where that's not guaranteed by `Array#-`.

@param minuend [Array] @param subtrahend [Array] @return [Array]

# File lib/sass/util.rb, line 346
def array_minus(minuend, subtrahend)
  return minuend - subtrahend unless rbx?
  set = Set.new(minuend) - subtrahend
  minuend.select {|e| set.include?(e)}
end
atomic_create_and_write_file(filename, perms = 0666) { |tmpfile| ... } click to toggle source

This creates a temp file and yields it for writing. When the write is complete, the file is moved into the desired location. The atomicity of this operation is provided by the filesystem's rename operation.

@param filename [String] The file to write to. @param perms [Integer] The permissions used for creating this file.

Will be masked by the process umask. Defaults to readable/writeable
by all users however the umask usually changes this to only be writable
by the process's user.

@yieldparam tmpfile [Tempfile] The temp file that can be written to. @return The value returned by the block.

# File lib/sass/util.rb, line 1222
def atomic_create_and_write_file(filename, perms = 0666)
  require 'tempfile'
  tmpfile = Tempfile.new(File.basename(filename), File.dirname(filename))
  tmpfile.binmode if tmpfile.respond_to?(:binmode)
  result = yield tmpfile
  tmpfile.close
  ATOMIC_WRITE_MUTEX.synchronize do
    begin
      File.chmod(perms & ~File.umask, tmpfile.path)
    rescue Errno::EPERM
      # If we don't have permissions to chmod the file, don't let that crash
      # the compilation. See issue 1215.
    end
    File.rename tmpfile.path, filename
  end
  result
ensure
  # close and remove the tempfile if it still exists,
  # presumably due to an error during write
  tmpfile.close if tmpfile
  tmpfile.unlink if tmpfile
end
av_template_class(name) click to toggle source

Returns an ActionView::Template* class. In pre-3.0 versions of Rails, most of these classes were of the form `ActionView::TemplateFoo`, while afterwards they were of the form `ActionView;:Template::Foo`.

@param name [#to_s] The name of the class to get.

For example, `:Error` will return `ActionView::TemplateError`
or `ActionView::Template::Error`.
# File lib/sass/util.rb, line 592
def av_template_class(name)
  return ActionView.const_get("Template#{name}") if ActionView.const_defined?("Template#{name}")
  ActionView::Template.const_get(name.to_s)
end
caller_info(entry = nil) click to toggle source

Returns information about the caller of the previous method.

@param entry [String] An entry in the `#caller` list, or a similarly formatted string @return [[String, Fixnum, (String, nil)]]

An array containing the filename, line, and method name of the caller.
The method name may be nil
# File lib/sass/util.rb, line 421
def caller_info(entry = nil)
  # JRuby evaluates `caller` incorrectly when it's in an actual default argument.
  entry ||= caller[1]
  info = entry.scan(/^((?:[A-Za-z]:)?.*?):(-?.*?)(?::.*`(.+)')?$/).first
  info[1] = info[1].to_i
  # This is added by Rubinius to designate a block, but we don't care about it.
  info[2].sub!(/ \{\}\Z/, '') if info[2]
  info
end
check_range(name, range, value, unit = '') click to toggle source

Asserts that `value` falls within `range` (inclusive), leaving room for slight floating-point errors.

@param name [String] The name of the value. Used in the error message. @param range [Range] The allowed range of values. @param value [Numeric, Sass::Script::Value::Number] The value to check. @param unit [String] The unit of the value. Used in error reporting. @return [Numeric] `value` adjusted to fall within range, if it

was outside by a floating-point margin.
# File lib/sass/util.rb, line 387
def check_range(name, range, value, unit = '')
  grace = (-0.00001..0.00001)
  str = value.to_s
  value = value.value if value.is_a?(Sass::Script::Value::Number)
  return value if range.include?(value)
  return range.first if grace.include?(value - range.first)
  return range.last if grace.include?(value - range.last)
  raise ArgumentError.new(
    "#{name} #{str} must be between #{range.first}#{unit} and #{range.last}#{unit}")
end
check_sass_encoding(str) click to toggle source

Like {#check_encoding}, but also checks for a `@charset` declaration at the beginning of the file and uses that encoding if it exists.

Sass follows CSS's decoding rules.

@param str [String] The string of which to check the encoding @return [(String, Encoding)] The original string encoded as UTF-8,

and the source encoding of the string (or `nil` under Ruby 1.8)

@raise [Encoding::UndefinedConversionError] if the source encoding

cannot be converted to UTF-8

@raise [ArgumentError] if the document uses an unknown encoding with `@charset` @raise [Sass::SyntaxError] If the document declares an encoding that

doesn't match its contents, or it doesn't declare an encoding and its
contents are invalid in the native encoding.
# File lib/sass/util.rb, line 859
def check_sass_encoding(str)
  # On Ruby 1.8 we can't do anything complicated with encodings.
  # Instead, we just strip out a UTF-8 BOM if it exists and
  # sanitize according to Section 3.3 of CSS Syntax Level 3. We
  # don't sanitize null characters since they might be components
  # of other characters.
  if ruby1_8?
    return str.gsub(/\A\xEF\xBB\xBF/, '').gsub(/\r\n?|\f/, "\n"), nil
  end

  # Determine the fallback encoding following section 3.2 of CSS Syntax Level 3 and Encodings:
  # http://www.w3.org/TR/2013/WD-css-syntax-3-20130919/#determine-the-fallback-encoding
  # http://encoding.spec.whatwg.org/#decode
  binary = str.dup.force_encoding("BINARY")
  if binary.start_with?(UTF_8_BOM)
    binary.slice! 0, UTF_8_BOM.length
    str = binary.force_encoding('UTF-8')
  elsif binary.start_with?(UTF_16BE_BOM)
    binary.slice! 0, UTF_16BE_BOM.length
    str = binary.force_encoding('UTF-16BE')
  elsif binary.start_with?(UTF_16LE_BOM)
    binary.slice! 0, UTF_16LE_BOM.length
    str = binary.force_encoding('UTF-16LE')
  elsif binary =~ CHARSET_REGEXP
    charset = $1.force_encoding('US-ASCII')
    # Ruby 1.9.2 doesn't recognize a UTF-16 encoding without an endian marker.
    if ruby1_9_2? && charset.downcase == 'utf-16'
      encoding = Encoding.find('UTF-8')
    else
      encoding = Encoding.find(charset)
      if encoding.name == 'UTF-16' || encoding.name == 'UTF-16BE'
        encoding = Encoding.find('UTF-8')
      end
    end
    str = binary.force_encoding(encoding)
  elsif str.encoding.name == "ASCII-8BIT"
    # Normally we want to fall back on believing the Ruby string
    # encoding, but if that's just binary we want to make sure
    # it's valid UTF-8.
    str = str.force_encoding('utf-8')
  end

  find_encoding_error(str) unless str.valid_encoding?

  begin
    # If the string is valid, preprocess it according to section 3.3 of CSS Syntax Level 3.
    return str.encode("UTF-8").gsub(/\r\n?|\f/, "\n").tr("\u0000", "�"), str.encoding
  rescue EncodingError
    find_encoding_error(str)
  end
end
cleanpath(path) click to toggle source

Like `Pathname#cleanpath`, but normalizes Windows paths to always use backslash separators. Normally, `Pathname#cleanpath` actually does the reverse – it will convert backslashes to forward slashes, which can break `Pathname#relative_path_from`.

@param path [String, Pathname] @return [Pathname]

# File lib/sass/util.rb, line 673
def cleanpath(path)
  path = Pathname.new(path) unless path.is_a?(Pathname)
  pathname(path.cleanpath.to_s)
end
deprecated(obj, message = nil) click to toggle source

Prints a deprecation warning for the caller method.

@param obj [Object] `self` @param message [String] A message describing what to do instead.

# File lib/sass/util.rb, line 481
def deprecated(obj, message = nil)
  obj_class = obj.is_a?(Class) ? "#{obj}." : "#{obj.class}#"
  full_message = "DEPRECATION WARNING: #{obj_class}#{caller_info[2]} " +
    "will be removed in a future version of Sass.#{("\n" + message) if message}"
  Sass::Util.sass_warn full_message
end
destructure(val) click to toggle source

Prepare a value for a destructuring assignment (e.g. `a, b = val`). This works around a performance bug when using ActiveSupport, and only needs to be called when `val` is likely to be `nil` reasonably often.

See [this bug report](redmine.ruby-lang.org/issues/4917).

@param val [Object] @return [Object]

# File lib/sass/util.rb, line 758
def destructure(val)
  val || []
end
encode_vlq(value) click to toggle source

Encodes `value` as VLQ (en.wikipedia.org/wiki/VLQ).

@param value [Fixnum] @return [String] The encoded value

# File lib/sass/util.rb, line 1140
def encode_vlq(value)
  if value < 0
    value = ((-value) << 1) | 1
  else
    value <<= 1
  end

  result = ''
  begin
    digit = value & VLQ_BASE_MASK
    value >>= VLQ_BASE_SHIFT
    if value > 0
      digit |= VLQ_CONTINUATION_BIT
    end
    result << BASE64_DIGITS[digit]
  end while value > 0
  result
end
enum_cons(enum, n) click to toggle source

A version of `Enumerable#enum_cons` that works in Ruby 1.8 and 1.9.

@param enum [Enumerable] The enumerable to get the enumerator for @param n [Fixnum] The size of each cons @return [Enumerator] The consed enumerator

# File lib/sass/util.rb, line 942
def enum_cons(enum, n)
  ruby1_8? ? enum.enum_cons(n) : enum.each_cons(n)
end
enum_slice(enum, n) click to toggle source

A version of `Enumerable#enum_slice` that works in Ruby 1.8 and 1.9.

@param enum [Enumerable] The enumerable to get the enumerator for @param n [Fixnum] The size of each slice @return [Enumerator] The consed enumerator

# File lib/sass/util.rb, line 951
def enum_slice(enum, n)
  ruby1_8? ? enum.enum_slice(n) : enum.each_slice(n)
end
enum_with_index(enum) click to toggle source

A version of `Enumerable#enum_with_index` that works in Ruby 1.8 and 1.9.

@param enum [Enumerable] The enumerable to get the enumerator for @return [Enumerator] The with-index enumerator

# File lib/sass/util.rb, line 933
def enum_with_index(enum)
  ruby1_8? ? enum.enum_with_index : enum.each_with_index
end
escape_uri(string) click to toggle source

URI-escape `string`.

@param string [String] @return [String]

# File lib/sass/util.rb, line 1170
def escape_uri(string)
  URI_ESCAPE.escape string
end
extract!(array) { |e| ... } click to toggle source

Destructively removes all elements from an array that match a block, and returns the removed elements.

@param array [Array] The array from which to remove elements. @yield [el] Called for each element. @yieldparam el [*] The element to test. @yieldreturn [Boolean] Whether or not to extract the element. @return [Array] The extracted elements.

# File lib/sass/util.rb, line 963
def extract!(array)
  out = []
  array.reject! do |e|
    next false unless yield e
    out << e
    true
  end
  out
end
extract_values(arr) click to toggle source

Extracts the non-string vlaues from an array containing both strings and non-strings. These values are replaced with escape sequences. This can be undone using {#inject_values}.

This is useful e.g. when we want to do string manipulation on an interpolated string.

The precise format of the resulting string is not guaranteed. However, it is guaranteed that newlines and whitespace won't be affected.

@param arr [Array] The array from which values are extracted. @return [(String, Array)] The resulting string, and an array of extracted values.

# File lib/sass/util.rb, line 1025
def extract_values(arr)
  values = []
  mapped = arr.map do |e|
    next e.gsub('{', '{{') if e.is_a?(String)
    values << e
    next "{#{values.count - 1}}"
  end
  return mapped.join, values
end
file_uri_from_path(path) click to toggle source

Converts `path` to a “file:” URI. This handles Windows paths correctly.

@param path [String, Pathname] @return [String]

# File lib/sass/util.rb, line 724
def file_uri_from_path(path)
  path = path.to_s if path.is_a?(Pathname)
  path = path.tr('\', '/') if windows?
  path = Sass::Util.escape_uri(path)
  return path.start_with?('/') ? "file://" + path : path unless windows?
  return "file:///" + path.tr("\\", "/") if path =~ /^[a-zA-Z]:[\/\]/
  return "file:" + path.tr("\\", "/") if path =~ /\\[^\]+\[^\\/]+/
  path.tr("\\", "/")
end
flatten_vertically(arrs) click to toggle source

Flattens the first level of nested arrays in `arrs`. Unlike `Array#flatten`, this orders the result by taking the first values from each array in order, then the second, and so on.

@param arrs [Array] The array to flatten. @return [Array] The flattened array.

# File lib/sass/util.rb, line 987
def flatten_vertically(arrs)
  result = []
  arrs = arrs.map {|sub| sub.is_a?(Array) ? sub.dup : Array(sub)}
  until arrs.empty?
    arrs.reject! do |arr|
      result << arr.shift
      arr.empty?
    end
  end
  result
end
glob(path) { |f| ... } click to toggle source

Like `Dir.glob`, but works with backslash-separated paths on Windows.

@param path [String]

# File lib/sass/util.rb, line 644
def glob(path)
  path = path.gsub('\', '/') if windows?
  if block_given?
    Dir.glob(path) {|f| yield(f)}
  else
    Dir.glob(path)
  end
end
group_by_to_a(enum) { |e| ... } click to toggle source

Performs the equivalent of `enum.group_by.to_a`, but with a guaranteed order. Unlike {Util#hash_to_a}, the resulting order isn't sorted key order; instead, it's the same order as `#group_by` has under Ruby 1.9 (key appearance order).

@param enum [Enumerable] @return [Array<[Object, Array]>] An array of pairs.

# File lib/sass/util.rb, line 322
def group_by_to_a(enum)
  return enum.group_by {|e| yield(e)}.to_a unless ruby1_8?
  order = {}
  arr = []
  groups = enum.group_by do |e|
    res = yield(e)
    unless order.include?(res)
      order[res] = order.size
    end
    res
  end
  groups.each do |key, vals|
    arr[order[key]] = [key, vals]
  end
  arr
end
has?(attr, klass, method) click to toggle source

Checks to see if a class has a given method. For example:

Sass::Util.has?(:public_instance_method, String, :gsub) #=> true

Method collections like `Class#instance_methods` return strings in Ruby 1.8 and symbols in Ruby 1.9 and on, so this handles checking for them in a compatible way.

@param attr [#to_s] The (singular) name of the method-collection method

(e.g. `:instance_methods`, `:private_methods`)

@param klass [Module] The class to check the methods of which to check @param method [String, Symbol] The name of the method do check for @return [Boolean] Whether or not the given collection has the given method

# File lib/sass/util.rb, line 925
def has?(attr, klass, method)
  klass.send("#{attr}s").include?(ruby1_8? ? method.to_s : method.to_sym)
end
hash_to_a(hash) click to toggle source

Converts a Hash to an Array. This is usually identical to `Hash#to_a`, with the following exceptions:

  • In Ruby 1.8, `Hash#to_a` is not deterministically ordered, but this is.

  • In Ruby 1.9 when running tests, this is ordered in the same way it would be under Ruby 1.8 (sorted key order rather than insertion order).

@param hash [Hash] @return [Array]

# File lib/sass/util.rb, line 310
def hash_to_a(hash)
  return hash.to_a unless ruby1_8? || defined?(Test::Unit)
  hash.sort_by {|k, v| k}
end
inject_values(str, values) click to toggle source

Undoes {#extract_values} by transforming a string with escape sequences into an array of strings and non-string values.

@param str [String] The string with escape sequences. @param values [Array] The array of values to inject. @return [Array] The array of strings and values.

# File lib/sass/util.rb, line 1041
def inject_values(str, values)
  return [str.gsub('{{', '{')] if values.empty?
  # Add an extra { so that we process the tail end of the string
  result = (str + '{{').scan(/(.*?)(?:(\{\{)|\{(\d+)\})/m).map do |(pre, esc, n)|
    [pre, esc ? '{' : '', n ? values[n.to_i] : '']
  end.flatten(1)
  result[-2] = '' # Get rid of the extra {
  merge_adjacent_strings(result).reject {|s| s == ''}
end
inspect_obj(obj) click to toggle source

Like `Object#inspect`, but preserves non-ASCII characters rather than escaping them under Ruby 1.9.2. This is necessary so that the precompiled Haml template can be `#encode`d into `@options` before being evaluated.

@param obj {Object} @return {String}

# File lib/sass/util.rb, line 1006
def inspect_obj(obj)
  return obj.inspect unless version_geq(RUBY_VERSION, "1.9.2")
  return ':' + inspect_obj(obj.to_s) if obj.is_a?(Symbol)
  return obj.inspect unless obj.is_a?(String)
  '"' + obj.gsub(/[\x00-\x7F]+/) {|s| s.inspect[1...-1]} + '"'
end
intersperse(enum, val) click to toggle source

Intersperses a value in an enumerable, as would be done with `Array#join` but without concatenating the array together afterwards.

@param enum [Enumerable] @param val @return [Array]

# File lib/sass/util.rb, line 220
def intersperse(enum, val)
  enum.inject([]) {|a, e| a << e << val}[0...-1]
end
ironruby?() click to toggle source

Whether or not this is running on IronRuby.

@return [Boolean]

# File lib/sass/util.rb, line 613
def ironruby?
  return @ironruby if defined?(@ironruby)
  @ironruby = RUBY_ENGINE == "ironruby"
end
jruby1_6?() click to toggle source

Wehter or not this is running under JRuby 1.6 or lower.

# File lib/sass/util.rb, line 795
def jruby1_6?
  return @jruby1_6 if defined?(@jruby1_6)
  @jruby1_6 = jruby? && jruby_version[0] == 1 && jruby_version[1] < 7
end
jruby?() click to toggle source

Whether or not this is running on JRuby.

@return [Boolean]

# File lib/sass/util.rb, line 629
def jruby?
  return @jruby if defined?(@jruby)
  @jruby = RUBY_PLATFORM =~ /java/
end
jruby_version() click to toggle source

Returns an array of ints representing the JRuby version number.

@return [Array<Fixnum>]

# File lib/sass/util.rb, line 637
def jruby_version
  @jruby_version ||= ::JRUBY_VERSION.split(".").map {|s| s.to_i}
end
json_escape_string(s) click to toggle source

Escapes certain characters so that the result can be used as the JSON string value. Returns the original string if no escaping is necessary.

@param s [String] The string to be escaped @return [String] The escaped string

# File lib/sass/util.rb, line 1079
def json_escape_string(s)
  return s if s !~ /["\\b\f\n\r\t]/

  result = ""
  s.split("").each do |c|
    case c
    when '"', "\\"
      result << "\\" << c
    when "\n" then result << "\\n"
    when "\t" then result << "\\t"
    when "\r" then result << "\\r"
    when "\f" then result << "\\f"
    when "\b" then result << "\\b"
    else
      result << c
    end
  end
  result
end
json_value_of(v) click to toggle source

Converts the argument into a valid JSON value.

@param v [Fixnum, String, Array, Boolean, nil] @return [String]

# File lib/sass/util.rb, line 1103
def json_value_of(v)
  case v
  when Fixnum
    v.to_s
  when String
    "\"" + json_escape_string(v) + "\""
  when Array
    "[" + v.map {|x| json_value_of(x)}.join(",") + "]"
  when NilClass
    "null"
  when TrueClass
    "true"
  when FalseClass
    "false"
  else
    raise ArgumentError.new("Unknown type: #{v.class.name}")
  end
end
lcs(x, y, &block) click to toggle source

Computes a single longest common subsequence for `x` and `y`. If there are more than one longest common subsequences, the one returned is that which starts first in `x`.

@param x [Array] @param y [Array] @yield [a, b] An optional block to use in place of a check for equality

between elements of `x` and `y`.

@yieldreturn [Object, nil] If the two values register as equal,

this will return the value to use in the LCS array.

@return [Array] The LCS

# File lib/sass/util.rb, line 294
def lcs(x, y, &block)
  x = [nil, *x]
  y = [nil, *y]
  block ||= proc {|a, b| a == b && a}
  lcs_backtrace(lcs_table(x, y, &block), x, y, x.size - 1, y.size - 1, &block)
end
listen_geq_2?() click to toggle source

Returns whether this environment is using Listen version 2.0.0 or greater.

@return [Boolean]

# File lib/sass/util.rb, line 570
def listen_geq_2?
  return @listen_geq_2 unless @listen_geq_2.nil?
  @listen_geq_2 =
    begin
      # Make sure we're loading listen/version from the same place that
      # we're loading listen itself.
      load_listen!
      require 'listen/version'
      version_geq(::Listen::VERSION, '2.0.0')
    rescue LoadError
      false
    end
end
load_listen!() click to toggle source
# File lib/sass/util.rb, line 1245
def load_listen!
  if defined?(gem)
    begin
      gem 'listen', '>= 1.1.0', '< 3.0.0'
      require 'listen'
    rescue Gem::LoadError
      dir = scope("vendor/listen/lib")
      $LOAD_PATH.unshift dir
      begin
        require 'listen'
      rescue LoadError => e
        if version_geq(RUBY_VERSION, "1.9.3")
          version_constraint = "~> 3.0"
        else
          version_constraint = "~> 1.1"
        end
        e.message << "\n" <<
          "Run \"gem install listen --version '#{version_constraint}'\" to get it."
        raise e
      end
    end
  else
    begin
      require 'listen'
    rescue LoadError => e
      dir = scope("vendor/listen/lib")
      if $LOAD_PATH.include?(dir)
        raise e unless File.exist?(scope(".git"))
        e.message << "\n" <<
          'Run "git submodule update --init" to get the bundled version.'
      else
        $LOAD_PATH.unshift dir
        retry
      end
    end
  end
end
macruby?() click to toggle source

Whether or not this is running under MacRuby.

@return [Boolean]

# File lib/sass/util.rb, line 803
def macruby?
  return @macruby if defined?(@macruby)
  @macruby = RUBY_ENGINE == 'macruby'
end
map_hash(hash) { |k, v| ... } click to toggle source

Maps the key-value pairs of a hash according to a block.

@example

map_hash({:foo => "bar", :baz => "bang"}) {|k, v| [k.to_s, v.to_sym]}
  #=> {"foo" => :bar, "baz" => :bang}

@param hash [Hash] The hash to map @yield [key, value] A block in which the key-value pairs are transformed @yieldparam [key] The hash key @yieldparam [value] The hash value @yieldreturn [(Object, Object)] The new value for the `[key, value]` pair @return [Hash] The mapped hash @see map_keys @see map_vals

# File lib/sass/util.rb, line 98
def map_hash(hash)
  # Copy and modify is more performant than mapping to an array and using
  # to_hash on the result.
  rv = hash.class.new
  hash.each do |k, v|
    new_key, new_value = yield(k, v)
    new_key = hash.denormalize(new_key) if hash.is_a?(NormalizedMap) && new_key == k
    rv[new_key] = new_value
  end
  rv
end
map_keys(hash) { |k| ... } click to toggle source

Maps the keys in a hash according to a block.

@example

map_keys({:foo => "bar", :baz => "bang"}) {|k| k.to_s}
  #=> {"foo" => "bar", "baz" => "bang"}

@param hash [Hash] The hash to map @yield [key] A block in which the keys are transformed @yieldparam key [Object] The key that should be mapped @yieldreturn [Object] The new value for the key @return [Hash] The mapped hash @see map_vals @see map_hash

# File lib/sass/util.rb, line 58
def map_keys(hash)
  map_hash(hash) {|k, v| [yield(k), v]}
end
map_vals(hash) { |v| ... } click to toggle source

Maps the values in a hash according to a block.

@example

map_values({:foo => "bar", :baz => "bang"}) {|v| v.to_sym}
  #=> {:foo => :bar, :baz => :bang}

@param hash [Hash] The hash to map @yield [value] A block in which the values are transformed @yieldparam value [Object] The value that should be mapped @yieldreturn [Object] The new value for the value @return [Hash] The mapped hash @see map_keys @see map_hash

# File lib/sass/util.rb, line 74
def map_vals(hash)
  # We don't delegate to map_hash for performance here
  # because map_hash does more than is necessary.
  rv = hash.class.new
  hash = hash.as_stored if hash.is_a?(NormalizedMap)
  hash.each do |k, v|
    rv[k] = yield(v)
  end
  rv
end
max(val1, val2) click to toggle source

Returns the maximum of `val1` and `val2`. We use this over {Array.max} to avoid unnecessary garbage collection.

# File lib/sass/util.rb, line 354
def max(val1, val2)
  val1 > val2 ? val1 : val2
end
merge_adjacent_strings(arr) click to toggle source

Concatenates all strings that are adjacent in an array, while leaving other elements as they are.

@example

merge_adjacent_strings([1, "foo", "bar", 2, "baz"])
  #=> [1, "foobar", 2, "baz"]

@param arr [Array] @return [Array] The enumerable with strings merged

# File lib/sass/util.rb, line 160
def merge_adjacent_strings(arr)
  # Optimize for the common case of one element
  return arr if arr.size < 2
  arr.inject([]) do |a, e|
    if e.is_a?(String)
      if a.last.is_a?(String)
        a.last << e
      else
        a << e.dup
      end
    else
      a << e
    end
    a
  end
end
min(val1, val2) click to toggle source

Returns the minimum of `val1` and `val2`. We use this over {Array.min} to avoid unnecessary garbage collection.

# File lib/sass/util.rb, line 360
def min(val1, val2)
  val1 <= val2 ? val1 : val2
end
ord(c) click to toggle source

Returns the ASCII code of the given character.

@param c [String] All characters but the first are ignored. @return [Fixnum] The ASCII code of `c`.

# File lib/sass/util.rb, line 977
def ord(c)
  ruby1_8? ? c[0] : c.ord
end
ordered_hash(*pairs_or_hash) click to toggle source

Converts a hash or a list of pairs into an order-preserving hash.

On Ruby 1.8.7, this uses the orderedhash gem to simulate an order-preserving hash. On Ruby 1.9 and up, it just uses the native Hash class, since that preserves the order itself.

@overload #ordered_hash(hash)

@param hash [Hash] a normal hash to convert to an ordered hash
@return [Hash]

@overload #ordered_hash(*pairs)

@example
  ordered_hash([:foo, "bar"], [:baz, "bang"])
    #=> {:foo => "bar", :baz => "bang"}
  ordered_hash #=> {}
@param pairs [Array<(Object, Object)>] the list of key/value pairs for
  the hash.
@return [Hash]
# File lib/sass/util.rb, line 827
def ordered_hash(*pairs_or_hash)
  if pairs_or_hash.length == 1 && pairs_or_hash.first.is_a?(Hash)
    hash = pairs_or_hash.first
    return hash unless ruby1_8?
    return OrderedHash.new.merge hash
  end

  return Hash[pairs_or_hash] unless ruby1_8?
  (pairs_or_hash.is_a?(NormalizedMap) ? NormalizedMap : OrderedHash)[*pairs_or_hash.flatten(1)]
end
pathname(path) click to toggle source

Like `Pathname.new`, but normalizes Windows paths to always use backslash separators.

`Pathname#relative_path_from` can break if the two pathnames aren't consistent in their slash style.

@param path [String] @return [Pathname]

# File lib/sass/util.rb, line 661
def pathname(path)
  path = path.tr("/", "\\") if windows?
  Pathname.new(path)
end
paths(arrs) click to toggle source

Return an array of all possible paths through the given arrays.

@param arrs [Array<Array>] @return [Array<Arrays>]

@example

paths([[1, 2], [3, 4], [5]]) #=>
  # [[1, 3, 5],
  #  [2, 3, 5],
  #  [1, 4, 5],
  #  [2, 4, 5]]
# File lib/sass/util.rb, line 277
def paths(arrs)
  arrs.inject([[]]) do |paths, arr|
    arr.map {|e| paths.map {|path| path + [e]}}.flatten(1)
  end
end
powerset(arr) click to toggle source

Computes the powerset of the given array. This is the set of all subsets of the array.

@example

powerset([1, 2, 3]) #=>
  Set[Set[], Set[1], Set[2], Set[3], Set[1, 2], Set[2, 3], Set[1, 3], Set[1, 2, 3]]

@param arr [Enumerable] @return [Set<Set>] The subsets of `arr`

# File lib/sass/util.rb, line 118
def powerset(arr)
  arr.inject([Set.new].to_set) do |powerset, el|
    new_powerset = Set.new
    powerset.each do |subset|
      new_powerset << subset
      new_powerset << subset + [el]
    end
    new_powerset
  end
end
rails_env() click to toggle source

Returns the environment of the Rails application, if this is running in a Rails context. Returns `nil` if no such environment is defined.

@return [String, nil]

# File lib/sass/util.rb, line 537
def rails_env
  return ::Rails.env.to_s if defined?(::Rails.env)
  return RAILS_ENV.to_s if defined?(RAILS_ENV)
  nil
end
rails_root() click to toggle source

Returns the root of the Rails application, if this is running in a Rails context. Returns `nil` if no such root is defined.

@return [String, nil]

# File lib/sass/util.rb, line 523
def rails_root
  if defined?(::Rails.root)
    return ::Rails.root.to_s if ::Rails.root
    raise "ERROR: Rails.root is nil!"
  end
  return RAILS_ROOT.to_s if defined?(RAILS_ROOT)
  nil
end
rbx?() click to toggle source

Whether or not this is running on Rubinius.

@return [Boolean]

# File lib/sass/util.rb, line 621
def rbx?
  return @rbx if defined?(@rbx)
  @rbx = RUBY_ENGINE == "rbx"
end
realpath(path) click to toggle source

Returns `path` with all symlinks resolved.

@param path [String, Pathname] @return [Pathname]

# File lib/sass/util.rb, line 682
def realpath(path)
  path = Pathname.new(path) unless path.is_a?(Pathname)

  # Explicitly DON'T run #pathname here. We don't want to convert
  # to Windows directory separators because we're comparing these
  # against the paths returned by Listen, which use forward
  # slashes everywhere.
  begin
    path.realpath
  rescue SystemCallError
    # If [path] doesn't actually exist, don't bail, just
    # return the original.
    path
  end
end
relative_path_from(path, from) click to toggle source

Returns `path` relative to `from`.

This is like `Pathname#relative_path_from` except it accepts both strings and pathnames, it handles Windows path separators correctly, and it throws an error rather than crashing if the paths use different encodings (github.com/ruby/ruby/pull/713).

@param path [String, Pathname] @param from [String, Pathname] @return [Pathname?]

# File lib/sass/util.rb, line 708
def relative_path_from(path, from)
  pathname(path.to_s).relative_path_from(pathname(from.to_s))
rescue NoMethodError => e
  raise e unless e.name == :zero?

  # Work around https://github.com/ruby/ruby/pull/713.
  path = path.to_s
  from = from.to_s
  raise ArgumentError("Incompatible path encodings: #{path.inspect} is #{path.encoding}, " +
    "#{from.inspect} is #{from.encoding}")
end
replace_subseq(arr, subseq, replacement) click to toggle source

Non-destructively replaces all occurrences of a subsequence in an array with another subsequence.

@example

replace_subseq([1, 2, 3, 4, 5], [2, 3], [:a, :b])
  #=> [1, :a, :b, 4, 5]

@param arr [Array] The array whose subsequences will be replaced. @param subseq [Array] The subsequence to find and replace. @param replacement [Array] The sequence that `subseq` will be replaced with. @return [Array] `arr` with `subseq` replaced with `replacement`.

# File lib/sass/util.rb, line 188
def replace_subseq(arr, subseq, replacement)
  new = []
  matched = []
  i = 0
  arr.each do |elem|
    if elem != subseq[i]
      new.push(*matched)
      matched = []
      i = 0
      new << elem
      next
    end

    if i == subseq.length - 1
      matched = []
      i = 0
      new.push(*replacement)
    else
      matched << elem
      i += 1
    end
  end
  new.push(*matched)
  new
end
restrict(value, range) click to toggle source

Restricts a number to falling within a given range. Returns the number if it falls within the range, or the closest value in the range if it doesn't.

@param value [Numeric] @param range [Range<Numeric>] @return [Numeric]

# File lib/sass/util.rb, line 136
def restrict(value, range)
  [[value, range.first].max, range.last].min
end
retry_on_windows() { || ... } click to toggle source

Retries a filesystem operation if it fails on Windows. Windows has weird and flaky locking rules that can cause operations to fail.

@yield [] The filesystem operation.

# File lib/sass/util.rb, line 738
def retry_on_windows
  return yield unless windows?

  begin
    yield
  rescue SystemCallError
    sleep 0.1
    yield
  end
end
round(value) click to toggle source

Like [Fixnum.round], but leaves rooms for slight floating-point differences.

@param value [Numeric] @return [Numeric]

# File lib/sass/util.rb, line 145
def round(value)
  # If the number is within epsilon of X.5, round up (or down for negative
  # numbers).
  return value.round if (value % 1) - 0.5 <= -1 * Script::Value::Number.epsilon
  value > 0 ? value.ceil : value.floor
end
ruby1?() click to toggle source

Whether or not this is running under a Ruby version under 2.0.

@return [Boolean]

# File lib/sass/util.rb, line 767
def ruby1?
  return @ruby1 if defined?(@ruby1)
  @ruby1 = RUBY_VERSION_COMPONENTS[0] <= 1
end
ruby1_8?() click to toggle source

Whether or not this is running under Ruby 1.8 or lower.

Note that IronRuby counts as Ruby 1.8, because it doesn't support the Ruby 1.9 encoding API.

@return [Boolean]

# File lib/sass/util.rb, line 778
def ruby1_8?
  # IronRuby says its version is 1.9, but doesn't support any of the encoding APIs.
  # We have to fall back to 1.8 behavior.
  return @ruby1_8 if defined?(@ruby1_8)
  @ruby1_8 = ironruby? ||
               (RUBY_VERSION_COMPONENTS[0] == 1 && RUBY_VERSION_COMPONENTS[1] < 9)
end
ruby1_9_2?() click to toggle source

Whether or not this is running under Ruby 1.9.2 exactly.

@return [Boolean]

# File lib/sass/util.rb, line 789
def ruby1_9_2?
  return @ruby1_9_2 if defined?(@ruby1_9_2)
  @ruby1_9_2 = RUBY_VERSION_COMPONENTS == [1, 9, 2]
end
sass_warn(msg) click to toggle source

The same as `Kernel#warn`, but is silenced by {#silence_sass_warnings}.

@param msg [String]

# File lib/sass/util.rb, line 511
def sass_warn(msg)
  msg = msg + "\n" unless ruby1?
  Sass.logger.warn(msg)
end
scope(file) click to toggle source

Returns the path of a file relative to the Sass root directory.

@param file [String] The filename relative to the Sass root @return [String] The filename relative to the the working directory

# File lib/sass/util.rb, line 31
def scope(file)
  File.join(Sass::ROOT_DIR, file)
end
silence_sass_warnings() { || ... } click to toggle source

Silences all Sass warnings within a block.

@yield A block in which no Sass warnings will be printed

# File lib/sass/util.rb, line 501
def silence_sass_warnings
  old_level, Sass.logger.log_level = Sass.logger.log_level, :error
  yield
ensure
  Sass.logger.log_level = old_level
end
silence_warnings() { || ... } click to toggle source

Silence all output to STDERR within a block.

@yield A block in which no output will be printed to STDERR

# File lib/sass/util.rb, line 491
def silence_warnings
  the_real_stderr, $stderr = $stderr, StringIO.new
  yield
ensure
  $stderr = the_real_stderr
end
slice_by(enum) { |value| ... } click to toggle source
# File lib/sass/util.rb, line 224
def slice_by(enum)
  results = []
  enum.each do |value|
    key = yield(value)
    if !results.empty? && results.last.first == key
      results.last.last << value
    else
      results << [key, [value]]
    end
  end
  results
end
sourcemap_name(css) click to toggle source

Builds a sourcemap file name given the generated CSS file name.

@param css [String] The generated CSS file name. @return [String] The source map file name.

# File lib/sass/util.rb, line 1069
def sourcemap_name(css)
  css + ".map"
end
strip_string_array(arr) click to toggle source

Destructively strips whitespace from the beginning and end of the first and last elements, respectively, in the array (if those elements are strings).

@param arr [Array] @return [Array] `arr`

# File lib/sass/util.rb, line 260
def strip_string_array(arr)
  arr.first.lstrip! if arr.first.is_a?(String)
  arr.last.rstrip! if arr.last.is_a?(String)
  arr
end
subsequence?(seq1, seq2) click to toggle source

Returns whether or not `seq1` is a subsequence of `seq2`. That is, whether or not `seq2` contains every element in `seq1` in the same order (and possibly more elements besides).

@param seq1 [Array] @param seq2 [Array] @return [Boolean]

# File lib/sass/util.rb, line 405
def subsequence?(seq1, seq2)
  i = j = 0
  loop do
    return true if i == seq1.size
    return false if j == seq2.size
    i += 1 if seq1[i] == seq2[j]
    j += 1
  end
end
substitute(ary, from, to) click to toggle source

Substitutes a sub-array of one array with another sub-array.

@param ary [Array] The array in which to make the substitution @param from [Array] The sequence of elements to replace with `to` @param to [Array] The sequence of elements to replace `from` with

# File lib/sass/util.rb, line 242
def substitute(ary, from, to)
  res = ary.dup
  i = 0
  while i < res.size
    if res[i...i + from.size] == from
      res[i...i + from.size] = to
    end
    i += 1
  end
  res
end
to_hash(arr) click to toggle source

Converts an array of `[key, value]` pairs to a hash.

@example

to_hash([[:foo, "bar"], [:baz, "bang"]])
  #=> {:foo => "bar", :baz => "bang"}

@param arr [Array<(Object, Object)>] An array of pairs @return [Hash] A hash

# File lib/sass/util.rb, line 42
def to_hash(arr)
  ordered_hash(*arr.compact)
end
undefined_conversion_error_char(e) click to toggle source

Returns a string description of the character that caused an `Encoding::UndefinedConversionError`.

@param e [Encoding::UndefinedConversionError] @return [String]

# File lib/sass/util.rb, line 369
def undefined_conversion_error_char(e)
  # Rubinius (as of 2.0.0.rc1) pre-quotes the error character.
  return e.error_char if rbx?
  # JRuby (as of 1.7.2) doesn't have an error_char field on
  # Encoding::UndefinedConversionError.
  return e.error_char.dump unless jruby?
  e.message[/^"[^"]+"/] # "
end
version_geq(v1, v2) click to toggle source

Returns whether one version string represents the same or a more recent version than another.

@param v1 [String] A version string. @param v2 [String] Another version string. @return [Boolean]

# File lib/sass/util.rb, line 465
def version_geq(v1, v2)
  version_gt(v1, v2) || !version_gt(v2, v1)
end
version_gt(v1, v2) click to toggle source

Returns whether one version string represents a more recent version than another.

@param v1 [String] A version string. @param v2 [String] Another version string. @return [Boolean]

# File lib/sass/util.rb, line 436
def version_gt(v1, v2)
  # Construct an array to make sure the shorter version is padded with nil
  Array.new([v1.length, v2.length].max).zip(v1.split("."), v2.split(".")) do |_, p1, p2|
    p1 ||= "0"
    p2 ||= "0"
    release1 = p1 =~ /^[0-9]+$/
    release2 = p2 =~ /^[0-9]+$/
    if release1 && release2
      # Integer comparison if both are full releases
      p1, p2 = p1.to_i, p2.to_i
      next if p1 == p2
      return p1 > p2
    elsif !release1 && !release2
      # String comparison if both are prereleases
      next if p1 == p2
      return p1 > p2
    else
      # If only one is a release, that one is newer
      return release1
    end
  end
end
windows?() click to toggle source

Whether or not this is running on Windows.

@return [Boolean]

# File lib/sass/util.rb, line 605
def windows?
  return @windows if defined?(@windows)
  @windows = (RbConfig::CONFIG['host_os'] =~ /mswin|windows|mingw/i)
end
with_extracted_values(arr) { |str| ... } click to toggle source

Allows modifications to be performed on the string form of an array containing both strings and non-strings.

@param arr [Array] The array from which values are extracted. @yield [str] A block in which string manipulation can be done to the array. @yieldparam str [String] The string form of `arr`. @yieldreturn [String] The modified string. @return [Array] The modified, interpolated array.

# File lib/sass/util.rb, line 1059
def with_extracted_values(arr)
  str, vals = extract_values(arr)
  str = yield str
  inject_values(str, vals)
end

Private Instance Methods

find_encoding_error(str) click to toggle source
# File lib/sass/util.rb, line 1285
def find_encoding_error(str)
  encoding = str.encoding
  cr = Regexp.quote("\r".encode(encoding).force_encoding('BINARY'))
  lf = Regexp.quote("\n".encode(encoding).force_encoding('BINARY'))
  ff = Regexp.quote("\f".encode(encoding).force_encoding('BINARY'))
  line_break = /#{cr}#{lf}?|#{ff}|#{lf}/

  str.force_encoding("binary").split(line_break).each_with_index do |line, i|
    begin
      line.encode(encoding)
    rescue Encoding::UndefinedConversionError => e
      raise Sass::SyntaxError.new(
        "Invalid #{encoding.name} character #{undefined_conversion_error_char(e)}",
        :line => i + 1)
    end
  end

  # We shouldn't get here, but it's possible some weird encoding stuff causes it.
  return str, str.encoding
end
lcs_backtrace(c, x, y, i, j) { |x, y| ... } click to toggle source

Computes a single longest common subsequence for arrays x and y. Algorithm from [Wikipedia](en.wikipedia.org/wiki/Longest_common_subsequence_problem#Reading_out_an_LCS)

# File lib/sass/util.rb, line 1332
def lcs_backtrace(c, x, y, i, j, &block)
  # rubocop:enable ParameterList, LineLengths
  return [] if i == 0 || j == 0
  if (v = yield(x[i], y[j]))
    return lcs_backtrace(c, x, y, i - 1, j - 1, &block) << v
  end

  return lcs_backtrace(c, x, y, i, j - 1, &block) if c[i][j - 1] > c[i - 1][j]
  lcs_backtrace(c, x, y, i - 1, j, &block)
end
lcs_table(x, y) { |x, y| ... } click to toggle source

Calculates the memoization table for the Least Common Subsequence algorithm. Algorithm from [Wikipedia](en.wikipedia.org/wiki/Longest_common_subsequence_problem#Computing_the_length_of_the_LCS)

# File lib/sass/util.rb, line 1310
def lcs_table(x, y)
  # This method does not take a block as an explicit parameter for performance reasons.
  # rubocop:enable LineLength
  c = Array.new(x.size) {[]}
  x.size.times {|i| c[i][0] = 0}
  y.size.times {|j| c[0][j] = 0}
  (1...x.size).each do |i|
    (1...y.size).each do |j|
      c[i][j] =
        if yield x[i], y[j]
          c[i - 1][j - 1] + 1
        else
          [c[i][j - 1], c[i - 1][j]].max
        end
    end
  end
  c
end