Module | Haml::Util |
In: |
lib/haml/util/subset_map.rb
lib/haml/util.rb |
A module containing various useful functions.
RUBY_VERSION | = | ::RUBY_VERSION.split(".").map {|s| s.to_i} | An array of ints representing the Ruby version number. @api public | |
ENCODINGS_TO_CHECK | = | %w[UTF-8 UTF-16BE UTF-16LE UTF-32BE UTF-32LE] | We could automatically add in any non-ASCII-compatible encodings here, but there‘s not really a good way to do that without manually checking that each encoding encodes all ASCII characters properly, which takes long enough to affect the startup time of the CLI. | |
CHARSET_REGEXPS | = | Hash.new do |h, e| h[e] = begin # /\A(?:\uFEFF)?@charset "(.*?)"|\A(\uFEFF)/ Regexp.new(/\A(?:#{_enc("\uFEFF", e)})?#{ _enc('@charset "', e)}(.*?)#{_enc('"', e)}|\A(#{ _enc("\uFEFF", e)})/) |
@private
# File lib/haml/util.rb, line 512 512: def _enc(string, encoding) 513: string.encode(encoding).force_encoding("BINARY") 514: end
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/haml/util.rb, line 306 306: def ap_geq?(version) 307: # The ActionPack module is always loaded automatically in Rails >= 3 308: return false unless defined?(ActionPack) && defined?(ActionPack::VERSION) && 309: defined?(ActionPack::VERSION::STRING) 310: 311: ActionPack::VERSION::STRING >= version 312: end
Returns whether this environment is using ActionPack version 3.0.0 or greater.
@return [Boolean]
# File lib/haml/util.rb, line 295 295: def ap_geq_3? 296: ap_geq?("3.0.0.beta1") 297: end
Assert that a given object (usually a String) is HTML safe according to Rails’ XSS handling, if it‘s loaded.
@param text [Object]
# File lib/haml/util.rb, line 354 354: def assert_html_safe!(text) 355: return unless rails_xss_safe? && text && !text.to_s.html_safe? 356: raise Haml::Error.new("Expected #{text.inspect} to be HTML-safe.") 357: end
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/haml/util.rb, line 322 322: def av_template_class(name) 323: return ActionView.const_get("Template#{name}") if ActionView.const_defined?("Template#{name}") 324: return ActionView::Template.const_get(name.to_s) 325: end
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/haml/util.rb, line 226 226: def caller_info(entry = caller[1]) 227: info = entry.scan(/^(.*?):(-?.*?)(?::.*`(.+)')?$/).first 228: info[1] = info[1].to_i 229: # This is added by Rubinius to designate a block, but we don't care about it. 230: info[2].sub!(/ \{\}\Z/, '') if info[2] 231: info 232: end
Checks that the encoding of a string is valid in Ruby 1.9 and cleans up potential encoding gotchas like the UTF-8 BOM. If it‘s not, yields an error string describing the invalid character and the line on which it occurrs.
@param str [String] The string of which to check the encoding @yield [msg] A block in which an encoding error can be raised.
Only yields if there is an encoding error
@yieldparam msg [String] The error message to be raised @return [String] `str`, potentially with encoding gotchas like BOMs removed
# File lib/haml/util.rb, line 407 407: def check_encoding(str) 408: if ruby1_8? 409: return str.gsub(/\A\xEF\xBB\xBF/, '') # Get rid of the UTF-8 BOM 410: elsif str.valid_encoding? 411: # Get rid of the Unicode BOM if possible 412: if str.encoding.name =~ /^UTF-(8|16|32)(BE|LE)?$/ 413: return str.gsub(Regexp.new("\\A\uFEFF".encode(str.encoding.name)), '') 414: else 415: return str 416: end 417: end 418: 419: encoding = str.encoding 420: newlines = Regexp.new("\r\n|\r|\n".encode(encoding).force_encoding("binary")) 421: str.force_encoding("binary").split(newlines).each_with_index do |line, i| 422: begin 423: line.encode(encoding) 424: rescue Encoding::UndefinedConversionError => e 425: yield <<MSG.rstrip, i + 1 426: Invalid #{encoding.name} character #{e.error_char.dump} 427: MSG 428: end 429: end 430: return str 431: end
Like {\check_encoding}, but also checks for a Ruby-style `-# coding:` comment at the beginning of the template and uses that encoding if it exists.
The Sass encoding rules are simple. If a `-# coding:` comment exists, we assume that that‘s the original encoding of the document. Otherwise, we use whatever encoding Ruby has.
Haml uses the same rules for parsing coding comments as Ruby. This means that it can understand Emacs-style comments (e.g. `-*- encoding: "utf-8" -*-`), and also that it cannot understand non-ASCII-compatible encodings such as `UTF-16` and `UTF-32`.
@param str [String] The Haml template of which to check the encoding @yield [msg] A block in which an encoding error can be raised.
Only yields if there is an encoding error
@yieldparam msg [String] The error message to be raised @return [String] The original string encoded properly @raise [ArgumentError] if the document declares an unknown encoding
# File lib/haml/util.rb, line 453 453: def check_haml_encoding(str, &block) 454: return check_encoding(str, &block) if ruby1_8? 455: str = str.dup if str.frozen? 456: 457: bom, encoding = parse_haml_magic_comment(str) 458: if encoding; str.force_encoding(encoding) 459: elsif bom; str.force_encoding("UTF-8") 460: end 461: 462: return check_encoding(str, &block) 463: end
Like {\check_encoding}, but also checks for a `@charset` declaration at the beginning of the file and uses that encoding if it exists.
The Sass encoding rules are simple. If a `@charset` declaration exists, we assume that that‘s the original encoding of the document. Otherwise, we use whatever encoding Ruby has. Then we convert that to UTF-8 to process internally. The UTF-8 end result is what‘s returned by this method.
@param str [String] The string of which to check the encoding @yield [msg] A block in which an encoding error can be raised.
Only yields if there is an encoding error
@yieldparam msg [String] The error message to be raised @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`
# File lib/haml/util.rb, line 484 484: def check_sass_encoding(str, &block) 485: return check_encoding(str, &block), nil if ruby1_8? 486: # We allow any printable ASCII characters but double quotes in the charset decl 487: bin = str.dup.force_encoding("BINARY") 488: encoding = Haml::Util::ENCODINGS_TO_CHECK.find do |enc| 489: bin =~ Haml::Util::CHARSET_REGEXPS[enc] 490: end 491: charset, bom = $1, $2 492: if charset 493: charset = charset.force_encoding(encoding).encode("UTF-8") 494: if endianness = encoding[/[BL]E$/] 495: begin 496: Encoding.find(charset + endianness) 497: charset << endianness 498: rescue ArgumentError # Encoding charset + endianness doesn't exist 499: end 500: end 501: str.force_encoding(charset) 502: elsif bom 503: str.force_encoding(encoding) 504: end 505: 506: str = check_encoding(str, &block) 507: return str.encode("UTF-8"), str.encoding 508: end
The same as `Kernel#warn`, but is silenced by \{silence_haml_warnings}.
@param msg [String]
# File lib/haml/util.rb, line 259 259: def haml_warn(msg) 260: return if @@silence_warnings 261: warn(msg) 262: end
Returns the given text, marked as being HTML-safe. With older versions of the Rails XSS-safety mechanism, this destructively modifies the HTML-safety of `text`.
@param text [String, nil] @return [String, nil] `text`, marked as HTML-safe
# File lib/haml/util.rb, line 344 344: def html_safe(text) 345: return unless text 346: return text.html_safe if defined?(ActiveSupport::SafeBuffer) 347: text.html_safe! 348: end
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/haml/util.rb, line 153 153: def intersperse(enum, val) 154: enum.inject([]) {|a, e| a << e << val}[0...-1] 155: end
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/haml/util.rb, line 214 214: def lcs(x, y, &block) 215: x = [nil, *x] 216: y = [nil, *y] 217: block ||= proc {|a, b| a == b && a} 218: lcs_backtrace(lcs_table(x, y, &block), x, y, x.size-1, y.size-1, &block) 219: end
Maps the key-value pairs of a hash according to a block. For 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/haml/util.rb, line 88 88: def map_hash(hash, &block) 89: to_hash(hash.map(&block)) 90: end
Maps the keys in a hash according to a block. For 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/haml/util.rb, line 53 53: def map_keys(hash) 54: to_hash(hash.map {|k, v| [yield(k), v]}) 55: end
Maps the values in a hash according to a block. For 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/haml/util.rb, line 70 70: def map_vals(hash) 71: to_hash(hash.map {|k, v| [k, yield(v)]}) 72: end
Concatenates all strings that are adjacent in an array, while leaving other elements as they are. For example:
merge_adjacent_strings([1, "foo", "bar", 2, "baz"]) #=> [1, "foobar", 2, "baz"]
@param enum [Enumerable] @return [Array] The enumerable with strings merged
# File lib/haml/util.rb, line 132 132: def merge_adjacent_strings(enum) 133: enum.inject([]) do |a, e| 134: if e.is_a?(String) 135: if a.last.is_a?(String) 136: a.last << e 137: else 138: a << e.dup 139: end 140: else 141: a << e 142: end 143: a 144: end 145: end
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/haml/util.rb, line 197 197: def paths(arrs) 198: arrs.inject([[]]) do |paths, arr| 199: flatten(arr.map {|e| paths.map {|path| path + [e]}}, 1) 200: end 201: end
Computes the powerset of the given array. This is the set of all subsets of the array. For 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/haml/util.rb, line 101 101: def powerset(arr) 102: arr.inject([Set.new].to_set) do |powerset, el| 103: new_powerset = Set.new 104: powerset.each do |subset| 105: new_powerset << subset 106: new_powerset << subset + [el] 107: end 108: new_powerset 109: end 110: end
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/haml/util.rb, line 285 285: def rails_env 286: return Rails.env.to_s if defined?(Rails.root) 287: return RAILS_ENV.to_s if defined?(RAILS_ENV) 288: return nil 289: end
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/haml/util.rb, line 271 271: def rails_root 272: if defined?(Rails.root) 273: return Rails.root.to_s if Rails.root 274: raise "ERROR: Rails.root is nil!" 275: end 276: return RAILS_ROOT.to_s if defined?(RAILS_ROOT) 277: return nil 278: end
The class for the Rails SafeBuffer XSS protection class. This varies depending on Rails version.
@return [Class]
# File lib/haml/util.rb, line 363 363: def rails_safe_buffer_class 364: # It's important that we check ActiveSupport first, 365: # because in Rails 2.3.6 ActionView::SafeBuffer exists 366: # but is a deprecated proxy object. 367: return ActiveSupport::SafeBuffer if defined?(ActiveSupport::SafeBuffer) 368: return ActionView::SafeBuffer 369: end
Whether or not ActionView‘s XSS protection is available and enabled, as is the default for Rails 3.0+, and optional for version 2.3.5+. Overridden in haml/template.rb if this is the case.
@return [Boolean]
# File lib/haml/util.rb, line 334 334: def rails_xss_safe? 335: false 336: end
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/haml/util.rb, line 119 119: def restrict(value, range) 120: [[value, range.first].max, range.last].min 121: end
Whether or not this is running under Ruby 1.8 or lower.
@return [Boolean]
# File lib/haml/util.rb, line 385 385: def ruby1_8? 386: Haml::Util::RUBY_VERSION[0] == 1 && Haml::Util::RUBY_VERSION[1] < 9 387: end
Whether or not this is running under Ruby 1.8.6 or lower. Note that lower versions are not officially supported.
@return [Boolean]
# File lib/haml/util.rb, line 393 393: def ruby1_8_6? 394: ruby1_8? && Haml::Util::RUBY_VERSION[2] < 7 395: end
Silences all Haml warnings within a block.
@yield A block in which no Haml warnings will be printed
# File lib/haml/util.rb, line 248 248: def silence_haml_warnings 249: old_silence_warnings = @@silence_warnings 250: @@silence_warnings = true 251: yield 252: ensure 253: @@silence_warnings = old_silence_warnings 254: end
Silence all output to STDERR within a block.
@yield A block in which no output will be printed to STDERR
# File lib/haml/util.rb, line 237 237: def silence_warnings 238: the_real_stderr, $stderr = $stderr, StringIO.new 239: yield 240: ensure 241: $stderr = the_real_stderr 242: end
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/haml/util.rb, line 180 180: def strip_string_array(arr) 181: arr.first.lstrip! if arr.first.is_a?(String) 182: arr.last.rstrip! if arr.last.is_a?(String) 183: arr 184: end
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/haml/util.rb, line 162 162: def substitute(ary, from, to) 163: res = ary.dup 164: i = 0 165: while i < res.size 166: if res[i...i+from.size] == from 167: res[i...i+from.size] = to 168: end 169: i += 1 170: end 171: res 172: end
Converts an array of `[key, value]` pairs to a hash. For 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/haml/util.rb, line 36 36: def to_hash(arr) 37: arr.compact.inject({}) {|h, (k, v)| h[k] = v; h} 38: end