class File

Public Class Methods

append( file, str ) click to toggle source

Append to a file.

CREDIT: George Moschovitis

# File lib/core/facets/file/append.rb, line 7
def self.append( file, str )
  File.open( file, 'ab' ) { |f|
    f << str
  }
end
create(path, str='', &blk) click to toggle source

Creates a new file, or overwrites an existing file, and writes a string into it. Can also take a block just like File#open, which is yielded after the string is writ.

str = 'The content for the file'
File.create('myfile.txt', str)

CREDIT: George Moschovitis

# File lib/core/facets/file/create.rb, line 13
def self.create(path, str='', &blk)
  open(path, 'wb') do |f|
    f << str
    blk.call(f) if blk
  end
end
null() click to toggle source

Platform dependent null device.

CREDIT: Daniel Burger

# File lib/core/facets/file/null.rb, line 7
def self.null
  case RUBY_PLATFORM
  when /mswin/
    'NUL'
  when /amiga/
    'NIL:'
  when /openvms/
    'NL:'
  else
    '/dev/null'
  end
end
read_binary(fname) click to toggle source

Read in a file as binary data.

CREDIT: George Moschovitis

# File lib/core/facets/file/read.rb, line 18
def self.read_binary(fname)
  open(fname, 'rb') {|f|
    return f.read
  }
end
read_list(filepath, chomp_string='') click to toggle source

Reads in a file, removes blank lines and remarks (lines starting with '#') and then returns an array of all the remaining lines.

CREDIT: Trans

# File lib/core/facets/file/read.rb, line 30
def self.read_list(filepath, chomp_string='')
  farr = nil
  farr = read(filepath).split("\n")
  farr.collect! { |line|
    l = line.strip.chomp(chomp_string)
    (l.empty? or l[0,1] == '#') ? nil : l
  }
  farr.compact
end
rewrite(name, mode = "") { || ... } click to toggle source

Opens a file as a string and writes back the string to the file at the end of the block.

Returns the number of written bytes or nil if the file wasn't modified.

Note that the file will even be written back in case the block raises an exception.

Mode can either be “b” or “+” and specifies to open the file in binary mode (no mapping of the plattform's newlines to “n” is done) or to append to it.

# Reverse contents of "message"
File.rewrite("message") { |str| str.reverse }

# Replace "foo" by "bar" in "binary"
File.rewrite("binary", "b") { |str| str.gsub("foo", "bar") }

IMPORTANT: The old version of this method required in place modification of the file string. The new version will write whatever the block returns instead!!!

CREDIT: George Moschovitis

# File lib/core/facets/file/rewrite.rb, line 28
def self.rewrite(name, mode = "") #:yield:
  unless block_given?
    raise(ArgumentError, "Need to supply block to File.rewrite")
  end

  if mode.is_a?(Numeric) then
    flag, mode = mode, ""
    mode += "b" if flag & File::Constants::BINARY != 0
    mode += "+" if flag & File::Constants::APPEND != 0
  else
    mode.delete!("^b+")
  end

  old_str = open(name, "r#{mode}") { |file| file.read } #rescue ""
  old_str = old_str.clone

  begin
    new_str = yield(old_str)
  ensure
    if old_str != new_str
      open(name, "w#{mode}") { |file| file.write(new_str) }
    end
  end
end
rewrite!(name, mode = "") { || ... } click to toggle source

In place version of rewrite. This version of method requires that the string be modified in place within the block.

# Reverse contents of "message"
File.rewrite("message") { |str| str.reverse! }

# Replace "foo" by "bar" in "binary"
File.rewrite("binary", "b") { |str| str.gsub!("foo", "bar") }
# File lib/core/facets/file/rewrite.rb, line 62
def self.rewrite!(name, mode = "") #:yield:
  unless block_given?
    raise(ArgumentError, "Need to supply block to File.rewrite")
  end

  if mode.is_a?(Numeric) then
    flag, mode = mode, ""
    mode += "b" if flag & File::Constants::BINARY != 0
    mode += "+" if flag & File::Constants::APPEND != 0
  else
    mode.delete!("^b+")
  end

  old_str = open(name, "r#{mode}") { |file| file.read } #rescue ""
  new_str = old_str.clone

  begin
    yield(new_str)
  ensure
    if old_str != new_str
      open(name, "w#{mode}") { |file| file.write(str) }
    end
  end
end
rootname(path) click to toggle source

Returns onlt the first portion of the directory of a file path name.

File.rootname('lib/jump.rb')  #=> 'lib'
File.rootname('/jump.rb')     #=> '/'
File.rootname('jump.rb')      #=> '.'

CREDIT: Trans

# File lib/core/facets/file/rootname.rb, line 12
def self.rootname(path)
  # this should be fairly robust
  path_re = Regexp.new('[' + Regexp.escape(File::Separator + %q{\/}) + ']')

  head, tail = path.split(path_re, 2)
  return '.' if path == head
  return '/' if head.empty?
  return head
end
sanitize(filename) click to toggle source

Cleans up a filename to ensure it will work on filesystem.

CREDIT: George Moschovitis

# File lib/core/facets/file/read.rb, line 7
def self.sanitize(filename)
  filename = File.basename(filename.gsub("\\", "/")) # work-around for IE
  filename.gsub!(/[^a-zA-Z0-9\.\-\+_]/,"_")
  filename = "_#{filename}" if filename =~ /^\.+$/
  filename
end
split_all(path) click to toggle source

Splits a file path into an array of individual path components. This differs from File.split, which divides the path into only two parts, directory path and basename.

File.split_all("a/b/c") =>  ['a', 'b', 'c']

CREDIT: Trans

# File lib/core/facets/file/split_all.rb, line 11
def self.split_all(path)
  head, tail = File.split(path)
  return [tail] if head == '.' || tail == '/'
  return [head, tail] if head == '/'
  return split_all(head) + [tail]
end
split_root(path) click to toggle source

Return the head of path from the rest of the path.

File.split_root('etc/xdg/gtk')  #=> ['etc', 'xdg/gtk']
# File lib/core/facets/file/split_root.rb, line 7
def self.split_root(path)
  path_re = Regexp.new('[' + Regexp.escape(File::Separator + %q{\/}) + ']')
  path.split(path_re, 2)
end
write(path, data) click to toggle source

Writes the given data to the given path and closes the file. This is done in binary mode, complementing IO.read in standard Ruby.

Returns the number of bytes written.

CREDIT: Gavin Sinclair

# File lib/core/facets/file/write.rb, line 15
def self.write(path, data)
  File.open(path, "wb") do |file|
    return file.write(data)
  end
end
writelines(path, data) click to toggle source

Writes the given array of data to the given path and closes the file. This is done in binary mode, complementing IO.readlines in standard Ruby.

Note that readlines (the standard Ruby method) returns an array of lines with newlines intact, whereas writelines uses puts, and so appends newlines if necessary. In this small way, readlines and writelines are not exact opposites.

Returns nil.

CREDIT: Noah Gibbs, Gavin Sinclair

# File lib/core/facets/file/writelines.rb, line 16
def self.writelines(path, data)
  File.open(path, "wb") do |file|
    file.puts(data)
  end
end
yaml?(file) click to toggle source

Is a file a YAML file?

Note this isn't perfect. At present it depends on the use use of an initial document separator (eg. '—'). With YAML 1.1 the %YAML delaration will be manditory, so in the future this can be adapted to fit that standard.

# File lib/more/facets/yaml.rb, line 65
def self.yaml?(file)
  File.open(file) do |f|
    until f.eof?
      line = f.gets
      break true if line =~ /^---/
      break false unless line =~ /^(\s*#.*?|\s*)$/
    end
  end
end