Feature #1981 » ruby_19_csv_speedup_01.patch
| lib/csv.rb (working copy) | ||
|---|---|---|
|
# it can take multiple calls to <tt>@io.gets()</tt> to get a full line,
|
||
|
# because of \r and/or \n characters embedded in quoted fields
|
||
|
#
|
||
|
in_extended_col = false
|
||
|
csv = Array.new
|
||
|
loop do
|
||
|
# add another read to the line
|
||
|
(line += @io.gets(@row_sep)) rescue return nil
|
||
|
# copy the line so we can chop it up in parsing
|
||
|
parse = line.dup
|
||
|
parse = (@io.gets(@row_sep)) rescue nil
|
||
|
return nil unless parse
|
||
|
parse.sub!(@parsers[:line_end], "")
|
||
|
#
|
||
|
# I believe a blank line should be an <tt>Array.new</tt>, not Ruby 1.8
|
||
|
# CSV's <tt>[nil]</tt>
|
||
|
#
|
||
|
if parse.empty?
|
||
|
@lineno += 1
|
||
|
if @skip_blanks
|
||
|
line = ""
|
||
|
next
|
||
|
elsif @unconverted_fields
|
||
|
return add_unconverted_fields(Array.new, Array.new)
|
||
|
elsif @use_headers
|
||
|
return self.class::Row.new(Array.new, Array.new)
|
||
|
else
|
||
|
return Array.new
|
||
|
if csv.empty?
|
||
|
#
|
||
|
# I believe a blank line should be an <tt>Array.new</tt>, not Ruby 1.8
|
||
|
# CSV's <tt>[nil]</tt>
|
||
|
#
|
||
|
if parse.empty?
|
||
|
@lineno += 1
|
||
|
if @skip_blanks
|
||
|
next
|
||
|
elsif @unconverted_fields
|
||
|
return add_unconverted_fields(Array.new, Array.new)
|
||
|
elsif @use_headers
|
||
|
return self.class::Row.new(Array.new, Array.new)
|
||
|
else
|
||
|
return Array.new
|
||
|
end
|
||
|
end
|
||
|
end
|
||
|
#
|
||
|
# shave leading empty fields if needed, because the main parser chokes
|
||
|
# on these
|
||
|
#
|
||
|
csv = if parse.sub!(@parsers[:leading_fields], "")
|
||
|
[nil] * ($&.length / @col_sep.length)
|
||
|
else
|
||
|
Array.new
|
||
|
end
|
||
|
#
|
||
|
# then parse the main fields with a hyper-tuned Regexp from
|
||
|
# Mastering Regular Expressions, Second Edition
|
||
|
#
|
||
|
parse.gsub!(@parsers[:csv_row]) do
|
||
|
csv << if $1.nil? # we found an unquoted field
|
||
|
if $2.empty? # switch empty unquoted fields to +nil+...
|
||
|
nil # for Ruby 1.8 CSV compatibility
|
||
|
parts = parse.split(@col_sep, -1)
|
||
|
csv << nil if parts.empty?
|
||
|
# This loop is the hot path of csv parsing. Some things may be non-dry
|
||
|
# for a reason. Make sure to benchmark when refactoring.
|
||
|
parts.each do |part|
|
||
|
if in_extended_col
|
||
|
# If we are continuing a previous column
|
||
|
if part[-1] == @quote_char && part.count(@quote_char) % 2 != 0
|
||
|
# extended column ends
|
||
|
csv.last << part[0..-2]
|
||
|
csv.last.gsub!(@quote_char * 2, @quote_char)
|
||
|
in_extended_col = false
|
||
|
else
|
||
|
# I decided to take a strict approach to CSV parsing...
|
||
|
if $2.count(@parsers[:return_newline]).zero? # verify correctness
|
||
|
$2
|
||
|
else
|
||
|
# or throw an Exception
|
||
|
raise MalformedCSVError, "Unquoted fields do not allow " +
|
||
|
"\\r or \\n (line #{lineno + 1})."
|
||
|
end
|
||
|
csv.last << part
|
||
|
csv.last << @col_sep
|
||
|
end
|
||
|
else # we found a quoted field...
|
||
|
$1.gsub(@quote_char * 2, @quote_char) # unescape contents
|
||
|
elsif part[0] == @quote_char
|
||
|
# If we are staring a new quoted column
|
||
|
if part[-1] != @quote_char || part.count(@quote_char) % 2 != 0
|
||
|
# start an extended column
|
||
|
csv << part[1..-1]
|
||
|
csv.last << @col_sep
|
||
|
in_extended_col = true
|
||
|
else
|
||
|
# regular quoted column
|
||
|
csv << part[1..-2]
|
||
|
csv.last.gsub!(@quote_char * 2, @quote_char)
|
||
|
end
|
||
|
elsif part =~ @parsers[:quote_or_nl]
|
||
|
# Unquoted field with bad characters.
|
||
|
if part =~ @parsers[:nl_or_lf]
|
||
|
raise MalformedCSVError, "Unquoted fields do not allow " +
|
||
|
"\\r or \\n (line #{lineno + 1})."
|
||
|
else
|
||
|
raise MalformedCSVError, "Illegal quoting on line #{lineno + 1}."
|
||
|
end
|
||
|
else
|
||
|
# Regular ole unquoted field.
|
||
|
csv << (part.empty? ? nil : part)
|
||
|
end
|
||
|
"" # gsub!'s replacement, clear the field
|
||
|
end
|
||
|
# if parse is empty?(), we found all the fields on the line...
|
||
|
if parse.empty?
|
||
|
# Replace tacked on @col_sep with @row_sep if we are still in an extended
|
||
|
# column.
|
||
|
csv[-1][-1] = @row_sep if in_extended_col
|
||
|
if in_extended_col
|
||
|
# if we're at eof?(), a quoted field wasn't closed...
|
||
|
if @io.eof?
|
||
|
raise MalformedCSVError, "Unclosed quoted field on line #{lineno + 1}."
|
||
|
elsif @field_size_limit and csv.last.size >= @field_size_limit
|
||
|
raise MalformedCSVError, "Field size exceeded on line #{lineno + 1}."
|
||
|
end
|
||
|
# otherwise, we need to loop and pull some more data to complete the row
|
||
|
else
|
||
|
@lineno += 1
|
||
|
# save fields unconverted fields, if needed...
|
||
| ... | ... | |
|
# return the results
|
||
|
break csv
|
||
|
end
|
||
|
# if we're not empty?() but at eof?(), a quoted field wasn't closed...
|
||
|
if @io.eof?
|
||
|
raise MalformedCSVError, "Unclosed quoted field on line #{lineno + 1}."
|
||
|
elsif parse =~ @parsers[:bad_field]
|
||
|
raise MalformedCSVError, "Illegal quoting on line #{lineno + 1}."
|
||
|
elsif @field_size_limit and parse.length >= @field_size_limit
|
||
|
raise MalformedCSVError, "Field size exceeded on line #{lineno + 1}."
|
||
|
end
|
||
|
# otherwise, we need to loop and pull some more data to complete the row
|
||
|
end
|
||
|
end
|
||
|
alias_method :gets, :shift
|
||
| ... | ... | |
|
esc_row_sep = escape_re(@row_sep)
|
||
|
esc_quote = escape_re(@quote_char)
|
||
|
@parsers = {
|
||
|
# for empty leading fields
|
||
|
leading_fields: encode_re("\\A(?:", esc_col_sep, ")+"),
|
||
|
# The Primary Parser
|
||
|
csv_row: encode_re(
|
||
|
"\\G(?:\\A|", esc_col_sep, ")", # anchor the match
|
||
|
"(?:", esc_quote, # find quoted fields
|
||
|
"((?>[^", esc_quote, "]*)", # "unrolling the loop"
|
||
|
"(?>", esc_quote * 2, # double for escaping
|
||
|
"[^", esc_quote, "]*)*)",
|
||
|
esc_quote,
|
||
|
"|", # ... or ...
|
||
|
"([^", esc_quote, esc_col_sep, "]*))", # unquoted fields
|
||
|
"(?=", esc_col_sep, "|\\z)" # ensure field is ended
|
||
|
),
|
||
|
# a test for unescaped quotes
|
||
|
bad_field: encode_re(
|
||
|
"\\A", esc_col_sep, "?", # an optional comma
|
||
|
"(?:", esc_quote, # a quoted field
|
||
|
"(?>[^", esc_quote, "]*)", # "unrolling the loop"
|
||
|
"(?>", esc_quote * 2, # double for escaping
|
||
|
"[^", esc_quote, "]*)*",
|
||
|
esc_quote, # the closing quote
|
||
|
"[^", esc_quote, "]", # an extra character
|
||
|
"|", # ... or ...
|
||
|
"[^", esc_quote, esc_col_sep, "]+", # an unquoted field
|
||
|
esc_quote, ")" # an extra quote
|
||
|
),
|
||
|
# for detecting parse errors
|
||
|
quote_or_nl: encode_re("[", esc_quote, "\r\n]"),
|
||
|
nl_or_lf: encode_re("[\r\n]"),
|
||
|
# safer than chomp!()
|
||
|
line_end: encode_re(esc_row_sep, "\\z"),
|
||
|
# illegal unquoted characters
|
||