class Byebug::ListCommand


List parts of the source code.

def description 

def description
  %(l[ist][[-=]][ nn-mm]
    Lists lines of code forward from current line or from the place where
    code was last listed. If "list-" is specified, lists backwards
    instead. If "list=" is specified, lists from current line regardless
    of where code was last listed. A line range can also be specified to
    list specific sections of code.)
end

def display_list(b, e, lines, current)


otherwise we return the previous line @state.previous_line.
current line number. If we can show from B to E then we return B,
Show file lines in LINES from line B to line E where CURRENT is the
# 
def display_list(b, e, lines, current)
  width = e.to_s.size
  b.upto(e) do |n|
    next unless n > 0 && lines[n - 1]
    line = n == current ? '=>' : '  '
    line += format(" %#{width}d: %s", n, lines[n - 1].chomp)
    puts(line)
  end
  e == lines.size ? @state.previous_line : b
end

def execute 

def execute
  Byebug.source_reload if Setting[:autoreload]
  lines = get_lines(@state.file)
  unless lines
    errmsg "No sourcefile available for #{@state.file}\n"
    return @state.previous_line
  end
  b, e = set_line_range(Setting[:listsize], lines.size)
  return @state.previous_line if b < 0
  puts "\n[#{b}, #{e}] in #{@state.file}"
  @state.previous_line = display_list(b, e, lines, @state.line)
end

def names 

def names
  %w(list)
end

def regexp 

def regexp
  /^\s* l(?:ist)? (?:\s*([-=])|\s+(\S+))? \s*$/x
end

def set_line_range(listsize, maxline)

Parameters:
  • maxline () -- - max line number that can be printed
  • listsize () -- - number of lines to be printed 
def set_line_range(listsize, maxline)
  if !@match || !(@match[1] || @match[2])
    b = if @state.previous_line
          @state.previous_line + listsize
        else
          @state.line - (listsize / 2)
        end
  elsif @match[1] == '-'
    b = if @state.previous_line
          if  @state.previous_line > 0
            @state.previous_line - listsize
          else
            @state.previous_line
          end
        else
          @state.line - (listsize / 2)
        end
  elsif @match[1] == '='
    @state.previous_line = nil
    b = @state.line - (listsize / 2)
  else
    b, e = @match[2].split(/[-,]/)
    if e
      b = b.to_i
      e = e.to_i
    else
      b = b.to_i - (listsize / 2)
    end
  end
  if b > maxline
    errmsg 'Invalid line range'
    return [-1, -1]
  end
  b = [1, b].max
  e ||=  b + listsize - 1
  if e > maxline
    e = maxline
    b = e - listsize + 1
    b = [1, b].max
  end
  [b, e]
end