Object
A buffer with source code. {Buffer} contains the source code itself, associated location information (name and first line), and takes care of encoding.
A source buffer is immutable once populated.
@!attribute [r] name
Buffer name. If the buffer was created from a file, the name corresponds to relative path to the file. @return [String] buffer name
@!attribute [r] first_line
First line of the buffer, 1 by default. @return [Integer] first line
@api public
@api private
# File lib/parser/source/buffer.rb, line 101 def initialize(name, first_line = 1) @name = name @source = nil @first_line = first_line @lines = nil @line_begins = nil end
Try to recognize encoding of `string` as Ruby would, i.e. by looking for magic encoding comment or UTF-8 BOM. `string` can be in any encoding.
@param [String] string @return [String|nil] encoding name, if recognized
# File lib/parser/source/buffer.rb, line 49 def self.recognize_encoding(string) return if string.empty? # extract the first two lines in an efficient way string =~ /\A(.*)\n?(.*\n)?/ first_line, second_line = $1, $2 if first_line =~ /\A\xef\xbb\xbf/ # BOM return Encoding::UTF_8 elsif first_line[0, 2] == '#!' encoding_line = second_line else encoding_line = first_line end if (result = ENCODING_RE.match(encoding_line)) Encoding.find(result[2] || result[3] || result[5]) else nil end end
Recognize encoding of `input` and process it so it could be lexed.
* If `input` does not contain BOM or magic encoding comment, it is kept in the original encoding. * If the detected encoding is binary, `input` is kept in binary. * Otherwise, `input` is re-encoded into UTF-8 and returned as a new string.
This method mutates the encoding of `input`, but not its content.
@param [String] input @return [String] @raise [EncodingError]
# File lib/parser/source/buffer.rb, line 86 def self.reencode_string(input) original_encoding = input.encoding detected_encoding = recognize_encoding(input.force_encoding(Encoding::BINARY)) if detected_encoding.nil? input.force_encoding(original_encoding) elsif detected_encoding == Encoding::BINARY input else input. force_encoding(detected_encoding). encode(Encoding::UTF_8) end end
Convert a character index into the source to a `[line, column]` tuple.
@param [Integer] position @return [[Integer, Integer]] `[line, column]`
# File lib/parser/source/buffer.rb, line 179 def decompose_position(position) line_no, line_begin = line_for(position) [ @first_line + line_no, position - line_begin ] end
Populate this buffer from a string without encoding autodetection.
@param [String] input @raise [ArgumentError] if already populated @return [String]
# File lib/parser/source/buffer.rb, line 165 def raw_source=(input) if @source raise ArgumentError, 'Source::Buffer is immutable' end @source = input.gsub("\r\n", "\n").freeze end
Populate this buffer from correspondingly named file.
@example
Parser::Source::Buffer.new('foo/bar.rb').read
@return [Buffer] self @raise [ArgumentError] if already populated
# File lib/parser/source/buffer.rb, line 119 def read File.open(@name, 'rb') do |io| self.source = io.read end self end
Source code contained in this buffer.
@return [String] source code @raise [RuntimeError] if buffer is not populated yet
# File lib/parser/source/buffer.rb, line 133 def source if @source.nil? raise RuntimeError, 'Cannot extract source from uninitialized Source::Buffer' end @source end
Populate this buffer from a string with encoding autodetection. `input` is mutated if not frozen.
@param [String] input @raise [ArgumentError] if already populated @return [String]
# File lib/parser/source/buffer.rb, line 149 def source=(input) if defined?(Encoding) input = input.dup if input.frozen? input = self.class.reencode_string(input) end self.raw_source = input end
Extract line `lineno` from source, taking `first_line` into account.
@param [Integer] lineno @return [String] @raise [IndexError] if `lineno` is out of bounds
# File lib/parser/source/buffer.rb, line 192 def source_line(lineno) unless @lines @lines = @source.lines.to_a @lines.each { |line| line.chomp!("\n") } # If a file ends with a newline, the EOF token will appear # to be one line further than the end of file. @lines << "" end @lines.fetch(lineno - @first_line).dup end
Generated with the Darkfish Rdoc Generator 2.