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Edit File: csv.rb
# encoding: US-ASCII # frozen_string_literal: true # = csv.rb -- CSV Reading and Writing # # Created by James Edward Gray II on 2005-10-31. # # See CSV for documentation. # # == Description # # Welcome to the new and improved CSV. # # This version of the CSV library began its life as FasterCSV. FasterCSV was # intended as a replacement to Ruby's then standard CSV library. It was # designed to address concerns users of that library had and it had three # primary goals: # # 1. Be significantly faster than CSV while remaining a pure Ruby library. # 2. Use a smaller and easier to maintain code base. (FasterCSV eventually # grew larger, was also but considerably richer in features. The parsing # core remains quite small.) # 3. Improve on the CSV interface. # # Obviously, the last one is subjective. I did try to defer to the original # interface whenever I didn't have a compelling reason to change it though, so # hopefully this won't be too radically different. # # We must have met our goals because FasterCSV was renamed to CSV and replaced # the original library as of Ruby 1.9. If you are migrating code from 1.8 or # earlier, you may have to change your code to comply with the new interface. # # == What's the Different From the Old CSV? # # I'm sure I'll miss something, but I'll try to mention most of the major # differences I am aware of, to help others quickly get up to speed: # # === \CSV Parsing # # * This parser is m17n aware. See CSV for full details. # * This library has a stricter parser and will throw MalformedCSVErrors on # problematic data. # * This library has a less liberal idea of a line ending than CSV. What you # set as the <tt>:row_sep</tt> is law. It can auto-detect your line endings # though. # * The old library returned empty lines as <tt>[nil]</tt>. This library calls # them <tt>[]</tt>. # * This library has a much faster parser. # # === Interface # # * CSV now uses Hash-style parameters to set options. # * CSV no longer has generate_row() or parse_row(). # * The old CSV's Reader and Writer classes have been dropped. # * CSV::open() is now more like Ruby's open(). # * CSV objects now support most standard IO methods. # * CSV now has a new() method used to wrap objects like String and IO for # reading and writing. # * CSV::generate() is different from the old method. # * CSV no longer supports partial reads. It works line-by-line. # * CSV no longer allows the instance methods to override the separators for # performance reasons. They must be set in the constructor. # # If you use this library and find yourself missing any functionality I have # trimmed, please {let me know}[mailto:james@grayproductions.net]. # # == Documentation # # See CSV for documentation. # # == What is CSV, really? # # CSV maintains a pretty strict definition of CSV taken directly from # {the RFC}[http://www.ietf.org/rfc/rfc4180.txt]. I relax the rules in only one # place and that is to make using this library easier. CSV will parse all valid # CSV. # # What you don't want to do is to feed CSV invalid data. Because of the way the # CSV format works, it's common for a parser to need to read until the end of # the file to be sure a field is invalid. This consumes a lot of time and memory. # # Luckily, when working with invalid CSV, Ruby's built-in methods will almost # always be superior in every way. For example, parsing non-quoted fields is as # easy as: # # data.split(",") # # == Questions and/or Comments # # Feel free to email {James Edward Gray II}[mailto:james@grayproductions.net] # with any questions. require "forwardable" require "English" require "date" require "stringio" require_relative "csv/fields_converter" require_relative "csv/match_p" require_relative "csv/parser" require_relative "csv/row" require_relative "csv/table" require_relative "csv/writer" using CSV::MatchP if CSV.const_defined?(:MatchP) # == \CSV # \CSV (comma-separated variables) data is a text representation of a table: # - A _row_ _separator_ delimits table rows. # A common row separator is the newline character <tt>"\n"</tt>. # - A _column_ _separator_ delimits fields in a row. # A common column separator is the comma character <tt>","</tt>. # # This \CSV \String, with row separator <tt>"\n"</tt> # and column separator <tt>","</tt>, # has three rows and two columns: # "foo,0\nbar,1\nbaz,2\n" # # Despite the name \CSV, a \CSV representation can use different separators. # # For more about tables, see the Wikipedia article # "{Table (information)}[https://en.wikipedia.org/wiki/Table_(information)]", # especially its section # "{Simple table}[https://en.wikipedia.org/wiki/Table_(information)#Simple_table]" # # == \Class \CSV # # Class \CSV provides methods for: # - Parsing \CSV data from a \String object, a \File (via its file path), or an \IO object. # - Generating \CSV data to a \String object. # # To make \CSV available: # require 'csv' # # All examples here assume that this has been done. # # == Keeping It Simple # # A \CSV object has dozens of instance methods that offer fine-grained control # of parsing and generating \CSV data. # For many needs, though, simpler approaches will do. # # This section summarizes the singleton methods in \CSV # that allow you to parse and generate without explicitly # creating \CSV objects. # For details, follow the links. # # === Simple Parsing # # Parsing methods commonly return either of: # - An \Array of Arrays of Strings: # - The outer \Array is the entire "table". # - Each inner \Array is a row. # - Each \String is a field. # - A CSV::Table object. For details, see # {\CSV with Headers}[#class-CSV-label-CSV+with+Headers]. # # ==== Parsing a \String # # The input to be parsed can be a string: # string = "foo,0\nbar,1\nbaz,2\n" # # \Method CSV.parse returns the entire \CSV data: # CSV.parse(string) # => [["foo", "0"], ["bar", "1"], ["baz", "2"]] # # \Method CSV.parse_line returns only the first row: # CSV.parse_line(string) # => ["foo", "0"] # # \CSV extends class \String with instance method String#parse_csv, # which also returns only the first row: # string.parse_csv # => ["foo", "0"] # # ==== Parsing Via a \File Path # # The input to be parsed can be in a file: # string = "foo,0\nbar,1\nbaz,2\n" # path = 't.csv' # File.write(path, string) # # \Method CSV.read returns the entire \CSV data: # CSV.read(path) # => [["foo", "0"], ["bar", "1"], ["baz", "2"]] # # \Method CSV.foreach iterates, passing each row to the given block: # CSV.foreach(path) do |row| # p row # end # Output: # ["foo", "0"] # ["bar", "1"] # ["baz", "2"] # # \Method CSV.table returns the entire \CSV data as a CSV::Table object: # CSV.table(path) # => #<CSV::Table mode:col_or_row row_count:3> # # ==== Parsing from an Open \IO Stream # # The input to be parsed can be in an open \IO stream: # # \Method CSV.read returns the entire \CSV data: # File.open(path) do |file| # CSV.read(file) # end # => [["foo", "0"], ["bar", "1"], ["baz", "2"]] # # As does method CSV.parse: # File.open(path) do |file| # CSV.parse(file) # end # => [["foo", "0"], ["bar", "1"], ["baz", "2"]] # # \Method CSV.parse_line returns only the first row: # File.open(path) do |file| # CSV.parse_line(file) # end # => ["foo", "0"] # # \Method CSV.foreach iterates, passing each row to the given block: # File.open(path) do |file| # CSV.foreach(file) do |row| # p row # end # end # Output: # ["foo", "0"] # ["bar", "1"] # ["baz", "2"] # # \Method CSV.table returns the entire \CSV data as a CSV::Table object: # File.open(path) do |file| # CSV.table(file) # end # => #<CSV::Table mode:col_or_row row_count:3> # # === Simple Generating # # \Method CSV.generate returns a \String; # this example uses method CSV#<< to append the rows # that are to be generated: # output_string = CSV.generate do |csv| # csv << ['foo', 0] # csv << ['bar', 1] # csv << ['baz', 2] # end # output_string # => "foo,0\nbar,1\nbaz,2\n" # # \Method CSV.generate_line returns a \String containing the single row # constructed from an \Array: # CSV.generate_line(['foo', '0']) # => "foo,0\n" # # \CSV extends class \Array with instance method <tt>Array#to_csv</tt>, # which forms an \Array into a \String: # ['foo', '0'].to_csv # => "foo,0\n" # # === "Filtering" \CSV # # \Method CSV.filter provides a Unix-style filter for \CSV data. # The input data is processed to form the output data: # in_string = "foo,0\nbar,1\nbaz,2\n" # out_string = '' # CSV.filter(in_string, out_string) do |row| # row[0] = row[0].upcase # row[1] *= 4 # end # out_string # => "FOO,0000\nBAR,1111\nBAZ,2222\n" # # == \CSV Objects # # There are three ways to create a \CSV object: # - \Method CSV.new returns a new \CSV object. # - \Method CSV.instance returns a new or cached \CSV object. # - \Method \CSV() also returns a new or cached \CSV object. # # === Instance Methods # # \CSV has three groups of instance methods: # - Its own internally defined instance methods. # - Methods included by module Enumerable. # - Methods delegated to class IO. See below. # # ==== Delegated Methods # # For convenience, a CSV object will delegate to many methods in class IO. # (A few have wrapper "guard code" in \CSV.) You may call: # * IO#binmode # * #binmode? # * IO#close # * IO#close_read # * IO#close_write # * IO#closed? # * #eof # * #eof? # * IO#external_encoding # * IO#fcntl # * IO#fileno # * #flock # * IO#flush # * IO#fsync # * IO#internal_encoding # * #ioctl # * IO#isatty # * #path # * IO#pid # * IO#pos # * IO#pos= # * IO#reopen # * #rewind # * IO#seek # * #stat # * IO#string # * IO#sync # * IO#sync= # * IO#tell # * #to_i # * #to_io # * IO#truncate # * IO#tty? # # === Options # # The default values for options are: # DEFAULT_OPTIONS = { # # For both parsing and generating. # col_sep: ",", # row_sep: :auto, # quote_char: '"', # # For parsing. # field_size_limit: nil, # converters: nil, # unconverted_fields: nil, # headers: false, # return_headers: false, # header_converters: nil, # skip_blanks: false, # skip_lines: nil, # liberal_parsing: false, # nil_value: nil, # empty_value: "", # # For generating. # write_headers: nil, # quote_empty: true, # force_quotes: false, # write_converters: nil, # write_nil_value: nil, # write_empty_value: "", # strip: false, # } # # ==== Options for Parsing # # Options for parsing, described in detail below, include: # - +row_sep+: Specifies the row separator; used to delimit rows. # - +col_sep+: Specifies the column separator; used to delimit fields. # - +quote_char+: Specifies the quote character; used to quote fields. # - +field_size_limit+: Specifies the maximum field size allowed. # - +converters+: Specifies the field converters to be used. # - +unconverted_fields+: Specifies whether unconverted fields are to be available. # - +headers+: Specifies whether data contains headers, # or specifies the headers themselves. # - +return_headers+: Specifies whether headers are to be returned. # - +header_converters+: Specifies the header converters to be used. # - +skip_blanks+: Specifies whether blanks lines are to be ignored. # - +skip_lines+: Specifies how comments lines are to be recognized. # - +strip+: Specifies whether leading and trailing whitespace are # to be stripped from fields.. # - +liberal_parsing+: Specifies whether \CSV should attempt to parse # non-compliant data. # - +nil_value+: Specifies the object that is to be substituted for each null (no-text) field. # - +empty_value+: Specifies the object that is to be substituted for each empty field. # # :include: ../doc/csv/options/common/row_sep.rdoc # # :include: ../doc/csv/options/common/col_sep.rdoc # # :include: ../doc/csv/options/common/quote_char.rdoc # # :include: ../doc/csv/options/parsing/field_size_limit.rdoc # # :include: ../doc/csv/options/parsing/converters.rdoc # # :include: ../doc/csv/options/parsing/unconverted_fields.rdoc # # :include: ../doc/csv/options/parsing/headers.rdoc # # :include: ../doc/csv/options/parsing/return_headers.rdoc # # :include: ../doc/csv/options/parsing/header_converters.rdoc # # :include: ../doc/csv/options/parsing/skip_blanks.rdoc # # :include: ../doc/csv/options/parsing/skip_lines.rdoc # # :include: ../doc/csv/options/parsing/strip.rdoc # # :include: ../doc/csv/options/parsing/liberal_parsing.rdoc # # :include: ../doc/csv/options/parsing/nil_value.rdoc # # :include: ../doc/csv/options/parsing/empty_value.rdoc # # ==== Options for Generating # # Options for generating, described in detail below, include: # - +row_sep+: Specifies the row separator; used to delimit rows. # - +col_sep+: Specifies the column separator; used to delimit fields. # - +quote_char+: Specifies the quote character; used to quote fields. # - +write_headers+: Specifies whether headers are to be written. # - +force_quotes+: Specifies whether each output field is to be quoted. # - +quote_empty+: Specifies whether each empty output field is to be quoted. # - +write_converters+: Specifies the field converters to be used in writing. # - +write_nil_value+: Specifies the object that is to be substituted for each +nil+-valued field. # - +write_empty_value+: Specifies the object that is to be substituted for each empty field. # # :include: ../doc/csv/options/common/row_sep.rdoc # # :include: ../doc/csv/options/common/col_sep.rdoc # # :include: ../doc/csv/options/common/quote_char.rdoc # # :include: ../doc/csv/options/generating/write_headers.rdoc # # :include: ../doc/csv/options/generating/force_quotes.rdoc # # :include: ../doc/csv/options/generating/quote_empty.rdoc # # :include: ../doc/csv/options/generating/write_converters.rdoc # # :include: ../doc/csv/options/generating/write_nil_value.rdoc # # :include: ../doc/csv/options/generating/write_empty_value.rdoc # # === \CSV with Headers # # CSV allows to specify column names of CSV file, whether they are in data, or # provided separately. If headers are specified, reading methods return an instance # of CSV::Table, consisting of CSV::Row. # # # Headers are part of data # data = CSV.parse(<<~ROWS, headers: true) # Name,Department,Salary # Bob,Engineering,1000 # Jane,Sales,2000 # John,Management,5000 # ROWS # # data.class #=> CSV::Table # data.first #=> #<CSV::Row "Name":"Bob" "Department":"Engineering" "Salary":"1000"> # data.first.to_h #=> {"Name"=>"Bob", "Department"=>"Engineering", "Salary"=>"1000"} # # # Headers provided by developer # data = CSV.parse('Bob,Engineering,1000', headers: %i[name department salary]) # data.first #=> #<CSV::Row name:"Bob" department:"Engineering" salary:"1000"> # # === \Converters # # By default, each value (field or header) parsed by \CSV is formed into a \String. # You can use a _field_ _converter_ or _header_ _converter_ # to intercept and modify the parsed values: # - See {Field Converters}[#class-CSV-label-Field+Converters]. # - See {Header Converters}[#class-CSV-label-Header+Converters]. # # Also by default, each value to be written during generation is written 'as-is'. # You can use a _write_ _converter_ to modify values before writing. # - See {Write Converters}[#class-CSV-label-Write+Converters]. # # ==== Specifying \Converters # # You can specify converters for parsing or generating in the +options+ # argument to various \CSV methods: # - Option +converters+ for converting parsed field values. # - Option +header_converters+ for converting parsed header values. # - Option +write_converters+ for converting values to be written (generated). # # There are three forms for specifying converters: # - A converter proc: executable code to be used for conversion. # - A converter name: the name of a stored converter. # - A converter list: an array of converter procs, converter names, and converter lists. # # ===== Converter Procs # # This converter proc, +strip_converter+, accepts a value +field+ # and returns <tt>field.strip</tt>: # strip_converter = proc {|field| field.strip } # In this call to <tt>CSV.parse</tt>, # the keyword argument <tt>converters: string_converter</tt> # specifies that: # - \Proc +string_converter+ is to be called for each parsed field. # - The converter's return value is to replace the +field+ value. # Example: # string = " foo , 0 \n bar , 1 \n baz , 2 \n" # array = CSV.parse(string, converters: strip_converter) # array # => [["foo", "0"], ["bar", "1"], ["baz", "2"]] # # A converter proc can receive a second argument, +field_info+, # that contains details about the field. # This modified +strip_converter+ displays its arguments: # strip_converter = proc do |field, field_info| # p [field, field_info] # field.strip # end # string = " foo , 0 \n bar , 1 \n baz , 2 \n" # array = CSV.parse(string, converters: strip_converter) # array # => [["foo", "0"], ["bar", "1"], ["baz", "2"]] # Output: # [" foo ", #<struct CSV::FieldInfo index=0, line=1, header=nil>] # [" 0 ", #<struct CSV::FieldInfo index=1, line=1, header=nil>] # [" bar ", #<struct CSV::FieldInfo index=0, line=2, header=nil>] # [" 1 ", #<struct CSV::FieldInfo index=1, line=2, header=nil>] # [" baz ", #<struct CSV::FieldInfo index=0, line=3, header=nil>] # [" 2 ", #<struct CSV::FieldInfo index=1, line=3, header=nil>] # Each CSV::Info object shows: # - The 0-based field index. # - The 1-based line index. # - The field header, if any. # # ===== Stored \Converters # # A converter may be given a name and stored in a structure where # the parsing methods can find it by name. # # The storage structure for field converters is the \Hash CSV::Converters. # It has several built-in converter procs: # - <tt>:integer</tt>: converts each \String-embedded integer into a true \Integer. # - <tt>:float</tt>: converts each \String-embedded float into a true \Float. # - <tt>:date</tt>: converts each \String-embedded date into a true \Date. # - <tt>:date_time</tt>: converts each \String-embedded date-time into a true \DateTime # . # This example creates a converter proc, then stores it: # strip_converter = proc {|field| field.strip } # CSV::Converters[:strip] = strip_converter # Then the parsing method call can refer to the converter # by its name, <tt>:strip</tt>: # string = " foo , 0 \n bar , 1 \n baz , 2 \n" # array = CSV.parse(string, converters: :strip) # array # => [["foo", "0"], ["bar", "1"], ["baz", "2"]] # # The storage structure for header converters is the \Hash CSV::HeaderConverters, # which works in the same way. # It also has built-in converter procs: # - <tt>:downcase</tt>: Downcases each header. # - <tt>:symbol</tt>: Converts each header to a \Symbol. # # There is no such storage structure for write headers. # # ===== Converter Lists # # A _converter_ _list_ is an \Array that may include any assortment of: # - Converter procs. # - Names of stored converters. # - Nested converter lists. # # Examples: # numeric_converters = [:integer, :float] # date_converters = [:date, :date_time] # [numeric_converters, strip_converter] # [strip_converter, date_converters, :float] # # Like a converter proc, a converter list may be named and stored in either # \CSV::Converters or CSV::HeaderConverters: # CSV::Converters[:custom] = [strip_converter, date_converters, :float] # CSV::HeaderConverters[:custom] = [:downcase, :symbol] # # There are two built-in converter lists: # CSV::Converters[:numeric] # => [:integer, :float] # CSV::Converters[:all] # => [:date_time, :numeric] # # ==== Field \Converters # # With no conversion, all parsed fields in all rows become Strings: # string = "foo,0\nbar,1\nbaz,2\n" # ary = CSV.parse(string) # ary # => # => [["foo", "0"], ["bar", "1"], ["baz", "2"]] # # When you specify a field converter, each parsed field is passed to the converter; # its return value becomes the stored value for the field. # A converter might, for example, convert an integer embedded in a \String # into a true \Integer. # (In fact, that's what built-in field converter +:integer+ does.) # # There are three ways to use field \converters. # # - Using option {converters}[#class-CSV-label-Option+converters] with a parsing method: # ary = CSV.parse(string, converters: :integer) # ary # => [0, 1, 2] # => [["foo", 0], ["bar", 1], ["baz", 2]] # - Using option {converters}[#class-CSV-label-Option+converters] with a new \CSV instance: # csv = CSV.new(string, converters: :integer) # # Field converters in effect: # csv.converters # => [:integer] # csv.read # => [["foo", 0], ["bar", 1], ["baz", 2]] # - Using method #convert to add a field converter to a \CSV instance: # csv = CSV.new(string) # # Add a converter. # csv.convert(:integer) # csv.converters # => [:integer] # csv.read # => [["foo", 0], ["bar", 1], ["baz", 2]] # # Installing a field converter does not affect already-read rows: # csv = CSV.new(string) # csv.shift # => ["foo", "0"] # # Add a converter. # csv.convert(:integer) # csv.converters # => [:integer] # csv.read # => [["bar", 1], ["baz", 2]] # # There are additional built-in \converters, and custom \converters are also supported. # # ===== Built-In Field \Converters # # The built-in field converters are in \Hash CSV::Converters: # - Each key is a field converter name. # - Each value is one of: # - A \Proc field converter. # - An \Array of field converter names. # # Display: # CSV::Converters.each_pair do |name, value| # if value.kind_of?(Proc) # p [name, value.class] # else # p [name, value] # end # end # Output: # [:integer, Proc] # [:float, Proc] # [:numeric, [:integer, :float]] # [:date, Proc] # [:date_time, Proc] # [:all, [:date_time, :numeric]] # # Each of these converters transcodes values to UTF-8 before attempting conversion. # If a value cannot be transcoded to UTF-8 the conversion will # fail and the value will remain unconverted. # # Converter +:integer+ converts each field that Integer() accepts: # data = '0,1,2,x' # # Without the converter # csv = CSV.parse_line(data) # csv # => ["0", "1", "2", "x"] # # With the converter # csv = CSV.parse_line(data, converters: :integer) # csv # => [0, 1, 2, "x"] # # Converter +:float+ converts each field that Float() accepts: # data = '1.0,3.14159,x' # # Without the converter # csv = CSV.parse_line(data) # csv # => ["1.0", "3.14159", "x"] # # With the converter # csv = CSV.parse_line(data, converters: :float) # csv # => [1.0, 3.14159, "x"] # # Converter +:numeric+ converts with both +:integer+ and +:float+.. # # Converter +:date+ converts each field that Date::parse accepts: # data = '2001-02-03,x' # # Without the converter # csv = CSV.parse_line(data) # csv # => ["2001-02-03", "x"] # # With the converter # csv = CSV.parse_line(data, converters: :date) # csv # => [#<Date: 2001-02-03 ((2451944j,0s,0n),+0s,2299161j)>, "x"] # # Converter +:date_time+ converts each field that DateTime::parse accepts: # data = '2020-05-07T14:59:00-05:00,x' # # Without the converter # csv = CSV.parse_line(data) # csv # => ["2020-05-07T14:59:00-05:00", "x"] # # With the converter # csv = CSV.parse_line(data, converters: :date_time) # csv # => [#<DateTime: 2020-05-07T14:59:00-05:00 ((2458977j,71940s,0n),-18000s,2299161j)>, "x"] # # Converter +:numeric+ converts with both +:date_time+ and +:numeric+.. # # As seen above, method #convert adds \converters to a \CSV instance, # and method #converters returns an \Array of the \converters in effect: # csv = CSV.new('0,1,2') # csv.converters # => [] # csv.convert(:integer) # csv.converters # => [:integer] # csv.convert(:date) # csv.converters # => [:integer, :date] # # ===== Custom Field \Converters # # You can define a custom field converter: # strip_converter = proc {|field| field.strip } # string = " foo , 0 \n bar , 1 \n baz , 2 \n" # array = CSV.parse(string, converters: strip_converter) # array # => [["foo", "0"], ["bar", "1"], ["baz", "2"]] # You can register the converter in \Converters \Hash, # which allows you to refer to it by name: # CSV::Converters[:strip] = strip_converter # string = " foo , 0 \n bar , 1 \n baz , 2 \n" # array = CSV.parse(string, converters: :strip) # array # => [["foo", "0"], ["bar", "1"], ["baz", "2"]] # # ==== Header \Converters # # Header converters operate only on headers (and not on other rows). # # There are three ways to use header \converters; # these examples use built-in header converter +:dowhcase+, # which downcases each parsed header. # # - Option +header_converters+ with a singleton parsing method: # string = "Name,Count\nFoo,0\n,Bar,1\nBaz,2" # tbl = CSV.parse(string, headers: true, header_converters: :downcase) # tbl.class # => CSV::Table # tbl.headers # => ["name", "count"] # # - Option +header_converters+ with a new \CSV instance: # csv = CSV.new(string, header_converters: :downcase) # # Header converters in effect: # csv.header_converters # => [:downcase] # tbl = CSV.parse(string, headers: true) # tbl.headers # => ["Name", "Count"] # # - Method #header_convert adds a header converter to a \CSV instance: # csv = CSV.new(string) # # Add a header converter. # csv.header_convert(:downcase) # csv.header_converters # => [:downcase] # tbl = CSV.parse(string, headers: true) # tbl.headers # => ["Name", "Count"] # # ===== Built-In Header \Converters # # The built-in header \converters are in \Hash CSV::HeaderConverters. # The keys there are the names of the \converters: # CSV::HeaderConverters.keys # => [:downcase, :symbol] # # Converter +:downcase+ converts each header by downcasing it: # string = "Name,Count\nFoo,0\n,Bar,1\nBaz,2" # tbl = CSV.parse(string, headers: true, header_converters: :downcase) # tbl.class # => CSV::Table # tbl.headers # => ["name", "count"] # # Converter +:symbol+ converts each header by making it into a \Symbol: # string = "Name,Count\nFoo,0\n,Bar,1\nBaz,2" # tbl = CSV.parse(string, headers: true, header_converters: :symbol) # tbl.headers # => [:name, :count] # Details: # - Strips leading and trailing whitespace. # - Downcases the header. # - Replaces embedded spaces with underscores. # - Removes non-word characters. # - Makes the string into a \Symbol. # # ===== Custom Header \Converters # # You can define a custom header converter: # upcase_converter = proc {|header| header.upcase } # string = "Name,Value\nfoo,0\nbar,1\nbaz,2\n" # table = CSV.parse(string, headers: true, header_converters: upcase_converter) # table # => #<CSV::Table mode:col_or_row row_count:4> # table.headers # => ["NAME", "VALUE"] # You can register the converter in \HeaderConverters \Hash, # which allows you to refer to it by name: # CSV::HeaderConverters[:upcase] = upcase_converter # table = CSV.parse(string, headers: true, header_converters: :upcase) # table # => #<CSV::Table mode:col_or_row row_count:4> # table.headers # => ["NAME", "VALUE"] # # ===== Write \Converters # # When you specify a write converter for generating \CSV, # each field to be written is passed to the converter; # its return value becomes the new value for the field. # A converter might, for example, strip whitespace from a field. # # Using no write converter (all fields unmodified): # output_string = CSV.generate do |csv| # csv << [' foo ', 0] # csv << [' bar ', 1] # csv << [' baz ', 2] # end # output_string # => " foo ,0\n bar ,1\n baz ,2\n" # Using option +write_converters+ with two custom write converters: # strip_converter = proc {|field| field.respond_to?(:strip) ? field.strip : field } # upcase_converter = proc {|field| field.respond_to?(:upcase) ? field.upcase : field } # write_converters = [strip_converter, upcase_converter] # output_string = CSV.generate(write_converters: write_converters) do |csv| # csv << [' foo ', 0] # csv << [' bar ', 1] # csv << [' baz ', 2] # end # output_string # => "FOO,0\nBAR,1\nBAZ,2\n" # # === Character Encodings (M17n or Multilingualization) # # This new CSV parser is m17n savvy. The parser works in the Encoding of the IO # or String object being read from or written to. Your data is never transcoded # (unless you ask Ruby to transcode it for you) and will literally be parsed in # the Encoding it is in. Thus CSV will return Arrays or Rows of Strings in the # Encoding of your data. This is accomplished by transcoding the parser itself # into your Encoding. # # Some transcoding must take place, of course, to accomplish this multiencoding # support. For example, <tt>:col_sep</tt>, <tt>:row_sep</tt>, and # <tt>:quote_char</tt> must be transcoded to match your data. Hopefully this # makes the entire process feel transparent, since CSV's defaults should just # magically work for your data. However, you can set these values manually in # the target Encoding to avoid the translation. # # It's also important to note that while all of CSV's core parser is now # Encoding agnostic, some features are not. For example, the built-in # converters will try to transcode data to UTF-8 before making conversions. # Again, you can provide custom converters that are aware of your Encodings to # avoid this translation. It's just too hard for me to support native # conversions in all of Ruby's Encodings. # # Anyway, the practical side of this is simple: make sure IO and String objects # passed into CSV have the proper Encoding set and everything should just work. # CSV methods that allow you to open IO objects (CSV::foreach(), CSV::open(), # CSV::read(), and CSV::readlines()) do allow you to specify the Encoding. # # One minor exception comes when generating CSV into a String with an Encoding # that is not ASCII compatible. There's no existing data for CSV to use to # prepare itself and thus you will probably need to manually specify the desired # Encoding for most of those cases. It will try to guess using the fields in a # row of output though, when using CSV::generate_line() or Array#to_csv(). # # I try to point out any other Encoding issues in the documentation of methods # as they come up. # # This has been tested to the best of my ability with all non-"dummy" Encodings # Ruby ships with. However, it is brave new code and may have some bugs. # Please feel free to {report}[mailto:james@grayproductions.net] any issues you # find with it. # class CSV # The error thrown when the parser encounters illegal CSV formatting. class MalformedCSVError < RuntimeError attr_reader :line_number alias_method :lineno, :line_number def initialize(message, line_number) @line_number = line_number super("#{message} in line #{line_number}.") end end # # A FieldInfo Struct contains details about a field's position in the data # source it was read from. CSV will pass this Struct to some blocks that make # decisions based on field structure. See CSV.convert_fields() for an # example. # # <b><tt>index</tt></b>:: The zero-based index of the field in its row. # <b><tt>line</tt></b>:: The line of the data source this row is from. # <b><tt>header</tt></b>:: The header for the column, when available. # FieldInfo = Struct.new(:index, :line, :header) # A Regexp used to find and convert some common Date formats. DateMatcher = / \A(?: (\w+,?\s+)?\w+\s+\d{1,2},?\s+\d{2,4} | \d{4}-\d{2}-\d{2} )\z /x # A Regexp used to find and convert some common DateTime formats. DateTimeMatcher = / \A(?: (\w+,?\s+)?\w+\s+\d{1,2}\s+\d{1,2}:\d{1,2}:\d{1,2},?\s+\d{2,4} | \d{4}-\d{2}-\d{2}\s\d{2}:\d{2}:\d{2} | # ISO-8601 \d{4}-\d{2}-\d{2} (?:T\d{2}:\d{2}(?::\d{2}(?:\.\d+)?(?:[+-]\d{2}(?::\d{2})|Z)?)?)? )\z /x # The encoding used by all converters. ConverterEncoding = Encoding.find("UTF-8") # A \Hash containing the names and \Procs for the built-in field converters. # See {Built-In Field Converters}[#class-CSV-label-Built-In+Field+Converters]. # # This \Hash is intentionally left unfrozen, and may be extended with # custom field converters. # See {Custom Field Converters}[#class-CSV-label-Custom+Field+Converters]. Converters = { integer: lambda { |f| Integer(f.encode(ConverterEncoding)) rescue f }, float: lambda { |f| Float(f.encode(ConverterEncoding)) rescue f }, numeric: [:integer, :float], date: lambda { |f| begin e = f.encode(ConverterEncoding) e.match?(DateMatcher) ? Date.parse(e) : f rescue # encoding conversion or date parse errors f end }, date_time: lambda { |f| begin e = f.encode(ConverterEncoding) e.match?(DateTimeMatcher) ? DateTime.parse(e) : f rescue # encoding conversion or date parse errors f end }, all: [:date_time, :numeric], } # A \Hash containing the names and \Procs for the built-in header converters. # See {Built-In Header Converters}[#class-CSV-label-Built-In+Header+Converters]. # # This \Hash is intentionally left unfrozen, and may be extended with # custom field converters. # See {Custom Header Converters}[#class-CSV-label-Custom+Header+Converters]. HeaderConverters = { downcase: lambda { |h| h.encode(ConverterEncoding).downcase }, symbol: lambda { |h| h.encode(ConverterEncoding).downcase.gsub(/[^\s\w]+/, "").strip. gsub(/\s+/, "_").to_sym } } # Default values for method options. DEFAULT_OPTIONS = { # For both parsing and generating. col_sep: ",", row_sep: :auto, quote_char: '"', # For parsing. field_size_limit: nil, converters: nil, unconverted_fields: nil, headers: false, return_headers: false, header_converters: nil, skip_blanks: false, skip_lines: nil, liberal_parsing: false, nil_value: nil, empty_value: "", # For generating. write_headers: nil, quote_empty: true, force_quotes: false, write_converters: nil, write_nil_value: nil, write_empty_value: "", strip: false, }.freeze class << self # :call-seq: # instance(string, **options) # instance(io = $stdout, **options) # instance(string, **options) {|csv| ... } # instance(io = $stdout, **options) {|csv| ... } # # Creates or retrieves cached \CSV objects. # For arguments and options, see CSV.new. # # --- # # With no block given, returns a \CSV object. # # The first call to +instance+ creates and caches a \CSV object: # s0 = 's0' # csv0 = CSV.instance(s0) # csv0.class # => CSV # # Subsequent calls to +instance+ with that _same_ +string+ or +io+ # retrieve that same cached object: # csv1 = CSV.instance(s0) # csv1.class # => CSV # csv1.equal?(csv0) # => true # Same CSV object # # A subsequent call to +instance+ with a _different_ +string+ or +io+ # creates and caches a _different_ \CSV object. # s1 = 's1' # csv2 = CSV.instance(s1) # csv2.equal?(csv0) # => false # Different CSV object # # All the cached objects remains available: # csv3 = CSV.instance(s0) # csv3.equal?(csv0) # true # Same CSV object # csv4 = CSV.instance(s1) # csv4.equal?(csv2) # true # Same CSV object # # --- # # When a block is given, calls the block with the created or retrieved # \CSV object; returns the block's return value: # CSV.instance(s0) {|csv| :foo } # => :foo def instance(data = $stdout, **options) # create a _signature_ for this method call, data object and options sig = [data.object_id] + options.values_at(*DEFAULT_OPTIONS.keys.sort_by { |sym| sym.to_s }) # fetch or create the instance for this signature @@instances ||= Hash.new instance = (@@instances[sig] ||= new(data, **options)) if block_given? yield instance # run block, if given, returning result else instance # or return the instance end end # :call-seq: # filter(**options) {|row| ... } # filter(in_string, **options) {|row| ... } # filter(in_io, **options) {|row| ... } # filter(in_string, out_string, **options) {|row| ... } # filter(in_string, out_io, **options) {|row| ... } # filter(in_io, out_string, **options) {|row| ... } # filter(in_io, out_io, **options) {|row| ... } # # Reads \CSV input and writes \CSV output. # # For each input row: # - Forms the data into: # - A CSV::Row object, if headers are in use. # - An \Array of Arrays, otherwise. # - Calls the block with that object. # - Appends the block's return value to the output. # # Arguments: # * \CSV source: # * Argument +in_string+, if given, should be a \String object; # it will be put into a new StringIO object positioned at the beginning. # * Argument +in_io+, if given, should be an IO object that is # open for reading; on return, the IO object will be closed. # * If neither +in_string+ nor +in_io+ is given, # the input stream defaults to {ARGF}[https://ruby-doc.org/core/ARGF.html]. # * \CSV output: # * Argument +out_string+, if given, should be a \String object; # it will be put into a new StringIO object positioned at the beginning. # * Argument +out_io+, if given, should be an IO object that is # ppen for writing; on return, the IO object will be closed. # * If neither +out_string+ nor +out_io+ is given, # the output stream defaults to <tt>$stdout</tt>. # * Argument +options+ should be keyword arguments. # - Each argument name that is prefixed with +in_+ or +input_+ # is stripped of its prefix and is treated as an option # for parsing the input. # Option +input_row_sep+ defaults to <tt>$INPUT_RECORD_SEPARATOR</tt>. # - Each argument name that is prefixed with +out_+ or +output_+ # is stripped of its prefix and is treated as an option # for generating the output. # Option +output_row_sep+ defaults to <tt>$INPUT_RECORD_SEPARATOR</tt>. # - Each argument not prefixed as above is treated as an option # both for parsing the input and for generating the output. # - See {Options for Parsing}[#class-CSV-label-Options+for+Parsing] # and {Options for Generating}[#class-CSV-label-Options+for+Generating]. # # Example: # in_string = "foo,0\nbar,1\nbaz,2\n" # out_string = '' # CSV.filter(in_string, out_string) do |row| # row[0] = row[0].upcase # row[1] *= 4 # end # out_string # => "FOO,0000\nBAR,1111\nBAZ,2222\n" def filter(input=nil, output=nil, **options) # parse options for input, output, or both in_options, out_options = Hash.new, {row_sep: $INPUT_RECORD_SEPARATOR} options.each do |key, value| case key.to_s when /\Ain(?:put)?_(.+)\Z/ in_options[$1.to_sym] = value when /\Aout(?:put)?_(.+)\Z/ out_options[$1.to_sym] = value else in_options[key] = value out_options[key] = value end end # build input and output wrappers input = new(input || ARGF, **in_options) output = new(output || $stdout, **out_options) # process headers need_manual_header_output = (in_options[:headers] and out_options[:headers] == true and out_options[:write_headers]) if need_manual_header_output first_row = input.shift if first_row if first_row.is_a?(Row) headers = first_row.headers yield headers output << headers end yield first_row output << first_row end end # read, yield, write input.each do |row| yield row output << row end end # # :call-seq: # foreach(path, mode='r', **options) {|row| ... ) # foreach(io, mode='r', **options {|row| ... ) # foreach(path, mode='r', headers: ..., **options) {|row| ... ) # foreach(io, mode='r', headers: ..., **options {|row| ... ) # foreach(path, mode='r', **options) -> new_enumerator # foreach(io, mode='r', **options -> new_enumerator # # Calls the block with each row read from source +path+ or +io+. # # * Argument +path+, if given, must be the path to a file. # :include: ../doc/csv/arguments/io.rdoc # * Argument +mode+, if given, must be a \File mode # See {Open Mode}[IO.html#method-c-new-label-Open+Mode]. # * Arguments <tt>**options</tt> must be keyword options. # See {Options for Parsing}[#class-CSV-label-Options+for+Parsing]. # * This method optionally accepts an additional <tt>:encoding</tt> option # that you can use to specify the Encoding of the data read from +path+ or +io+. # You must provide this unless your data is in the encoding # given by <tt>Encoding::default_external</tt>. # Parsing will use this to determine how to parse the data. # You may provide a second Encoding to # have the data transcoded as it is read. For example, # encoding: 'UTF-32BE:UTF-8' # would read +UTF-32BE+ data from the file # but transcode it to +UTF-8+ before parsing. # # ====== Without Option +headers+ # # Without option +headers+, returns each row as an \Array object. # # These examples assume prior execution of: # string = "foo,0\nbar,1\nbaz,2\n" # path = 't.csv' # File.write(path, string) # # Read rows from a file at +path+: # CSV.foreach(path) {|row| p row } # Output: # ["foo", "0"] # ["bar", "1"] # ["baz", "2"] # # Read rows from an \IO object: # File.open(path) do |file| # CSV.foreach(file) {|row| p row } # end # # Output: # ["foo", "0"] # ["bar", "1"] # ["baz", "2"] # # Returns a new \Enumerator if no block given: # CSV.foreach(path) # => #<Enumerator: CSV:foreach("t.csv", "r")> # CSV.foreach(File.open(path)) # => #<Enumerator: CSV:foreach(#<File:t.csv>, "r")> # # Issues a warning if an encoding is unsupported: # CSV.foreach(File.open(path), encoding: 'foo:bar') {|row| } # Output: # warning: Unsupported encoding foo ignored # warning: Unsupported encoding bar ignored # # ====== With Option +headers+ # # With {option +headers+}[#class-CSV-label-Option+headers], # returns each row as a CSV::Row object. # # These examples assume prior execution of: # string = "Name,Count\nfoo,0\nbar,1\nbaz,2\n" # path = 't.csv' # File.write(path, string) # # Read rows from a file at +path+: # CSV.foreach(path, headers: true) {|row| p row } # # Output: # #<CSV::Row "Name":"foo" "Count":"0"> # #<CSV::Row "Name":"bar" "Count":"1"> # #<CSV::Row "Name":"baz" "Count":"2"> # # Read rows from an \IO object: # File.open(path) do |file| # CSV.foreach(file, headers: true) {|row| p row } # end # # Output: # #<CSV::Row "Name":"foo" "Count":"0"> # #<CSV::Row "Name":"bar" "Count":"1"> # #<CSV::Row "Name":"baz" "Count":"2"> # # --- # # Raises an exception if +path+ is a \String, but not the path to a readable file: # # Raises Errno::ENOENT (No such file or directory @ rb_sysopen - nosuch.csv): # CSV.foreach('nosuch.csv') {|row| } # # Raises an exception if +io+ is an \IO object, but not open for reading: # io = File.open(path, 'w') {|row| } # # Raises TypeError (no implicit conversion of nil into String): # CSV.foreach(io) {|row| } # # Raises an exception if +mode+ is invalid: # # Raises ArgumentError (invalid access mode nosuch): # CSV.foreach(path, 'nosuch') {|row| } # def foreach(path, mode="r", **options, &block) return to_enum(__method__, path, mode, **options) unless block_given? open(path, mode, **options) do |csv| csv.each(&block) end end # # :call-seq: # generate(csv_string, **options) {|csv| ... } # generate(**options) {|csv| ... } # # * Argument +csv_string+, if given, must be a \String object; # defaults to a new empty \String. # * Arguments +options+, if given, should be generating options. # See {Options for Generating}[#class-CSV-label-Options+for+Generating]. # # --- # # Creates a new \CSV object via <tt>CSV.new(csv_string, **options)</tt>; # calls the block with the \CSV object, which the block may modify; # returns the \String generated from the \CSV object. # # Note that a passed \String *is* modified by this method. # Pass <tt>csv_string</tt>.dup if the \String must be preserved. # # This method has one additional option: <tt>:encoding</tt>, # which sets the base Encoding for the output if no no +str+ is specified. # CSV needs this hint if you plan to output non-ASCII compatible data. # # --- # # Add lines: # input_string = "foo,0\nbar,1\nbaz,2\n" # output_string = CSV.generate(input_string) do |csv| # csv << ['bat', 3] # csv << ['bam', 4] # end # output_string # => "foo,0\nbar,1\nbaz,2\nbat,3\nbam,4\n" # input_string # => "foo,0\nbar,1\nbaz,2\nbat,3\nbam,4\n" # output_string.equal?(input_string) # => true # Same string, modified # # Add lines into new string, preserving old string: # input_string = "foo,0\nbar,1\nbaz,2\n" # output_string = CSV.generate(input_string.dup) do |csv| # csv << ['bat', 3] # csv << ['bam', 4] # end # output_string # => "foo,0\nbar,1\nbaz,2\nbat,3\nbam,4\n" # input_string # => "foo,0\nbar,1\nbaz,2\n" # output_string.equal?(input_string) # => false # Different strings # # Create lines from nothing: # output_string = CSV.generate do |csv| # csv << ['foo', 0] # csv << ['bar', 1] # csv << ['baz', 2] # end # output_string # => "foo,0\nbar,1\nbaz,2\n" # # --- # # Raises an exception if +csv_string+ is not a \String object: # # Raises TypeError (no implicit conversion of Integer into String) # CSV.generate(0) # def generate(str=nil, **options) encoding = options[:encoding] # add a default empty String, if none was given if str str = StringIO.new(str) str.seek(0, IO::SEEK_END) str.set_encoding(encoding) if encoding else str = +"" str.force_encoding(encoding) if encoding end csv = new(str, **options) # wrap yield csv # yield for appending csv.string # return final String end # :call-seq: # CSV.generate_line(ary) # CSV.generate_line(ary, **options) # # Returns the \String created by generating \CSV from +ary+ # using the specified +options+. # # Argument +ary+ must be an \Array. # # Special options: # * Option <tt>:row_sep</tt> defaults to <tt>$INPUT_RECORD_SEPARATOR</tt> # (<tt>$/</tt>).: # $INPUT_RECORD_SEPARATOR # => "\n" # * This method accepts an additional option, <tt>:encoding</tt>, which sets the base # Encoding for the output. This method will try to guess your Encoding from # the first non-+nil+ field in +row+, if possible, but you may need to use # this parameter as a backup plan. # # For other +options+, # see {Options for Generating}[#class-CSV-label-Options+for+Generating]. # # --- # # Returns the \String generated from an \Array: # CSV.generate_line(['foo', '0']) # => "foo,0\n" # # --- # # Raises an exception if +ary+ is not an \Array: # # Raises NoMethodError (undefined method `find' for :foo:Symbol) # CSV.generate_line(:foo) # def generate_line(row, **options) options = {row_sep: $INPUT_RECORD_SEPARATOR}.merge(options) str = +"" if options[:encoding] str.force_encoding(options[:encoding]) else fallback_encoding = nil output_encoding = nil row.each do |field| next unless field.is_a?(String) fallback_encoding ||= field.encoding next if field.ascii_only? output_encoding = field.encoding break end output_encoding ||= fallback_encoding if output_encoding str.force_encoding(output_encoding) end end (new(str, **options) << row).string end # # :call-seq: # open(file_path, mode = "rb", **options ) -> new_csv # open(io, mode = "rb", **options ) -> new_csv # open(file_path, mode = "rb", **options ) { |csv| ... } -> object # open(io, mode = "rb", **options ) { |csv| ... } -> object # # possible options elements: # hash form: # :invalid => nil # raise error on invalid byte sequence (default) # :invalid => :replace # replace invalid byte sequence # :undef => :replace # replace undefined conversion # :replace => string # replacement string ("?" or "\uFFFD" if not specified) # # * Argument +path+, if given, must be the path to a file. # :include: ../doc/csv/arguments/io.rdoc # * Argument +mode+, if given, must be a \File mode # See {Open Mode}[IO.html#method-c-new-label-Open+Mode]. # * Arguments <tt>**options</tt> must be keyword options. # See {Options for Generating}[#class-CSV-label-Options+for+Generating]. # * This method optionally accepts an additional <tt>:encoding</tt> option # that you can use to specify the Encoding of the data read from +path+ or +io+. # You must provide this unless your data is in the encoding # given by <tt>Encoding::default_external</tt>. # Parsing will use this to determine how to parse the data. # You may provide a second Encoding to # have the data transcoded as it is read. For example, # encoding: 'UTF-32BE:UTF-8' # would read +UTF-32BE+ data from the file # but transcode it to +UTF-8+ before parsing. # # --- # # These examples assume prior execution of: # string = "foo,0\nbar,1\nbaz,2\n" # path = 't.csv' # File.write(path, string) # # --- # # With no block given, returns a new \CSV object. # # Create a \CSV object using a file path: # csv = CSV.open(path) # csv # => #<CSV io_type:File io_path:"t.csv" encoding:UTF-8 lineno:0 col_sep:"," row_sep:"\n" quote_char:"\""> # # Create a \CSV object using an open \File: # csv = CSV.open(File.open(path)) # csv # => #<CSV io_type:File io_path:"t.csv" encoding:UTF-8 lineno:0 col_sep:"," row_sep:"\n" quote_char:"\""> # # --- # # With a block given, calls the block with the created \CSV object; # returns the block's return value: # # Using a file path: # csv = CSV.open(path) {|csv| p csv} # csv # => #<CSV io_type:File io_path:"t.csv" encoding:UTF-8 lineno:0 col_sep:"," row_sep:"\n" quote_char:"\""> # Output: # #<CSV io_type:File io_path:"t.csv" encoding:UTF-8 lineno:0 col_sep:"," row_sep:"\n" quote_char:"\""> # # Using an open \File: # csv = CSV.open(File.open(path)) {|csv| p csv} # csv # => #<CSV io_type:File io_path:"t.csv" encoding:UTF-8 lineno:0 col_sep:"," row_sep:"\n" quote_char:"\""> # Output: # #<CSV io_type:File io_path:"t.csv" encoding:UTF-8 lineno:0 col_sep:"," row_sep:"\n" quote_char:"\""> # # --- # # Raises an exception if the argument is not a \String object or \IO object: # # Raises TypeError (no implicit conversion of Symbol into String) # CSV.open(:foo) def open(filename, mode="r", **options) # wrap a File opened with the remaining +args+ with no newline # decorator file_opts = {universal_newline: false}.merge(options) options.delete(:invalid) options.delete(:undef) options.delete(:replace) begin f = File.open(filename, mode, **file_opts) rescue ArgumentError => e raise unless /needs binmode/.match?(e.message) and mode == "r" mode = "rb" file_opts = {encoding: Encoding.default_external}.merge(file_opts) retry end begin csv = new(f, **options) rescue Exception f.close raise end # handle blocks like Ruby's open(), not like the CSV library if block_given? begin yield csv ensure csv.close end else csv end end # # :call-seq: # parse(string) -> array_of_arrays # parse(io) -> array_of_arrays # parse(string, headers: ..., **options) -> csv_table # parse(io, headers: ..., **options) -> csv_table # parse(string, **options) {|row| ... } # parse(io, **options) {|row| ... } # # Parses +string+ or +io+ using the specified +options+. # # - Argument +string+ should be a \String object; # it will be put into a new StringIO object positioned at the beginning. # :include: ../doc/csv/arguments/io.rdoc # - Argument +options+: see {Options for Parsing}[#class-CSV-label-Options+for+Parsing] # # ====== Without Option +headers+ # # Without {option +headers+}[#class-CSV-label-Option+headers] case. # # These examples assume prior execution of: # string = "foo,0\nbar,1\nbaz,2\n" # path = 't.csv' # File.write(path, string) # # --- # # With no block given, returns an \Array of Arrays formed from the source. # # Parse a \String: # a_of_a = CSV.parse(string) # a_of_a # => [["foo", "0"], ["bar", "1"], ["baz", "2"]] # # Parse an open \File: # a_of_a = File.open(path) do |file| # CSV.parse(file) # end # a_of_a # => [["foo", "0"], ["bar", "1"], ["baz", "2"]] # # --- # # With a block given, calls the block with each parsed row: # # Parse a \String: # CSV.parse(string) {|row| p row } # # Output: # ["foo", "0"] # ["bar", "1"] # ["baz", "2"] # # Parse an open \File: # File.open(path) do |file| # CSV.parse(file) {|row| p row } # end # # Output: # ["foo", "0"] # ["bar", "1"] # ["baz", "2"] # # ====== With Option +headers+ # # With {option +headers+}[#class-CSV-label-Option+headers] case. # # These examples assume prior execution of: # string = "Name,Count\nfoo,0\nbar,1\nbaz,2\n" # path = 't.csv' # File.write(path, string) # # --- # # With no block given, returns a CSV::Table object formed from the source. # # Parse a \String: # csv_table = CSV.parse(string, headers: ['Name', 'Count']) # csv_table # => #<CSV::Table mode:col_or_row row_count:5> # # Parse an open \File: # csv_table = File.open(path) do |file| # CSV.parse(file, headers: ['Name', 'Count']) # end # csv_table # => #<CSV::Table mode:col_or_row row_count:4> # # --- # # With a block given, calls the block with each parsed row, # which has been formed into a CSV::Row object: # # Parse a \String: # CSV.parse(string, headers: ['Name', 'Count']) {|row| p row } # # Output: # # <CSV::Row "Name":"foo" "Count":"0"> # # <CSV::Row "Name":"bar" "Count":"1"> # # <CSV::Row "Name":"baz" "Count":"2"> # # Parse an open \File: # File.open(path) do |file| # CSV.parse(file, headers: ['Name', 'Count']) {|row| p row } # end # # Output: # # <CSV::Row "Name":"foo" "Count":"0"> # # <CSV::Row "Name":"bar" "Count":"1"> # # <CSV::Row "Name":"baz" "Count":"2"> # # --- # # Raises an exception if the argument is not a \String object or \IO object: # # Raises NoMethodError (undefined method `close' for :foo:Symbol) # CSV.parse(:foo) def parse(str, **options, &block) csv = new(str, **options) return csv.each(&block) if block_given? # slurp contents, if no block is given begin csv.read ensure csv.close end end # :call-seq: # CSV.parse_line(string) -> new_array or nil # CSV.parse_line(io) -> new_array or nil # CSV.parse_line(string, **options) -> new_array or nil # CSV.parse_line(io, **options) -> new_array or nil # CSV.parse_line(string, headers: true, **options) -> csv_row or nil # CSV.parse_line(io, headers: true, **options) -> csv_row or nil # # Returns the data created by parsing the first line of +string+ or +io+ # using the specified +options+. # # - Argument +string+ should be a \String object; # it will be put into a new StringIO object positioned at the beginning. # :include: ../doc/csv/arguments/io.rdoc # - Argument +options+: see {Options for Parsing}[#class-CSV-label-Options+for+Parsing] # # ====== Without Option +headers+ # # Without option +headers+, returns the first row as a new \Array. # # These examples assume prior execution of: # string = "foo,0\nbar,1\nbaz,2\n" # path = 't.csv' # File.write(path, string) # # Parse the first line from a \String object: # CSV.parse_line(string) # => ["foo", "0"] # # Parse the first line from a File object: # File.open(path) do |file| # CSV.parse_line(file) # => ["foo", "0"] # end # => ["foo", "0"] # # Returns +nil+ if the argument is an empty \String: # CSV.parse_line('') # => nil # # ====== With Option +headers+ # # With {option +headers+}[#class-CSV-label-Option+headers], # returns the first row as a CSV::Row object. # # These examples assume prior execution of: # string = "Name,Count\nfoo,0\nbar,1\nbaz,2\n" # path = 't.csv' # File.write(path, string) # # Parse the first line from a \String object: # CSV.parse_line(string, headers: true) # => #<CSV::Row "Name":"foo" "Count":"0"> # # Parse the first line from a File object: # File.open(path) do |file| # CSV.parse_line(file, headers: true) # end # => #<CSV::Row "Name":"foo" "Count":"0"> # # --- # # Raises an exception if the argument is +nil+: # # Raises ArgumentError (Cannot parse nil as CSV): # CSV.parse_line(nil) # def parse_line(line, **options) new(line, **options).each.first end # # :call-seq: # read(source, **options) -> array_of_arrays # read(source, headers: true, **options) -> csv_table # # Opens the given +source+ with the given +options+ (see CSV.open), # reads the source (see CSV#read), and returns the result, # which will be either an \Array of Arrays or a CSV::Table. # # Without headers: # string = "foo,0\nbar,1\nbaz,2\n" # path = 't.csv' # File.write(path, string) # CSV.read(path) # => [["foo", "0"], ["bar", "1"], ["baz", "2"]] # # With headers: # string = "Name,Value\nfoo,0\nbar,1\nbaz,2\n" # path = 't.csv' # File.write(path, string) # CSV.read(path, headers: true) # => #<CSV::Table mode:col_or_row row_count:4> def read(path, **options) open(path, **options) { |csv| csv.read } end # :call-seq: # CSV.readlines(source, **options) # # Alias for CSV.read. def readlines(path, **options) read(path, **options) end # :call-seq: # CSV.table(source, **options) # # Calls CSV.read with +source+, +options+, and certain default options: # - +headers+: +true+ # - +converbers+: +:numeric+ # - +header_converters+: +:symbol+ # # Returns a CSV::Table object. # # Example: # string = "Name,Value\nfoo,0\nbar,1\nbaz,2\n" # path = 't.csv' # File.write(path, string) # CSV.table(path) # => #<CSV::Table mode:col_or_row row_count:4> def table(path, **options) default_options = { headers: true, converters: :numeric, header_converters: :symbol, } options = default_options.merge(options) read(path, **options) end end # :call-seq: # CSV.new(string) # CSV.new(io) # CSV.new(string, **options) # CSV.new(io, **options) # # Returns the new \CSV object created using +string+ or +io+ # and the specified +options+. # # - Argument +string+ should be a \String object; # it will be put into a new StringIO object positioned at the beginning. # :include: ../doc/csv/arguments/io.rdoc # - Argument +options+: See: # * {Options for Parsing}[#class-CSV-label-Options+for+Parsing] # * {Options for Generating}[#class-CSV-label-Options+for+Generating] # For performance reasons, the options cannot be overridden # in a \CSV object, so those specified here will endure. # # In addition to the \CSV instance methods, several \IO methods are delegated. # See {Delegated Methods}[#class-CSV-label-Delegated+Methods]. # # --- # # Create a \CSV object from a \String object: # csv = CSV.new('foo,0') # csv # => #<CSV io_type:StringIO encoding:UTF-8 lineno:0 col_sep:"," row_sep:"\n" quote_char:"\""> # # Create a \CSV object from a \File object: # File.write('t.csv', 'foo,0') # csv = CSV.new(File.open('t.csv')) # csv # => #<CSV io_type:File io_path:"t.csv" encoding:UTF-8 lineno:0 col_sep:"," row_sep:"\n" quote_char:"\""> # # --- # # Raises an exception if the argument is +nil+: # # Raises ArgumentError (Cannot parse nil as CSV): # CSV.new(nil) # def initialize(data, col_sep: ",", row_sep: :auto, quote_char: '"', field_size_limit: nil, converters: nil, unconverted_fields: nil, headers: false, return_headers: false, write_headers: nil, header_converters: nil, skip_blanks: false, force_quotes: false, skip_lines: nil, liberal_parsing: false, internal_encoding: nil, external_encoding: nil, encoding: nil, nil_value: nil, empty_value: "", quote_empty: true, write_converters: nil, write_nil_value: nil, write_empty_value: "", strip: false) raise ArgumentError.new("Cannot parse nil as CSV") if data.nil? if data.is_a?(String) @io = StringIO.new(data) @io.set_encoding(encoding || data.encoding) else @io = data end @encoding = determine_encoding(encoding, internal_encoding) @base_fields_converter_options = { nil_value: nil_value, empty_value: empty_value, } @write_fields_converter_options = { nil_value: write_nil_value, empty_value: write_empty_value, } @initial_converters = converters @initial_header_converters = header_converters @initial_write_converters = write_converters @parser_options = { column_separator: col_sep, row_separator: row_sep, quote_character: quote_char, field_size_limit: field_size_limit, unconverted_fields: unconverted_fields, headers: headers, return_headers: return_headers, skip_blanks: skip_blanks, skip_lines: skip_lines, liberal_parsing: liberal_parsing, encoding: @encoding, nil_value: nil_value, empty_value: empty_value, strip: strip, } @parser = nil @parser_enumerator = nil @eof_error = nil @writer_options = { encoding: @encoding, force_encoding: (not encoding.nil?), force_quotes: force_quotes, headers: headers, write_headers: write_headers, column_separator: col_sep, row_separator: row_sep, quote_character: quote_char, quote_empty: quote_empty, } @writer = nil writer if @writer_options[:write_headers] end # :call-seq: # csv.col_sep -> string # # Returns the encoded column separator; used for parsing and writing; # see {Option +col_sep+}[#class-CSV-label-Option+col_sep]: # CSV.new('').col_sep # => "," def col_sep parser.column_separator end # :call-seq: # csv.row_sep -> string # # Returns the encoded row separator; used for parsing and writing; # see {Option +row_sep+}[#class-CSV-label-Option+row_sep]: # CSV.new('').row_sep # => "\n" def row_sep parser.row_separator end # :call-seq: # csv.quote_char -> character # # Returns the encoded quote character; used for parsing and writing; # see {Option +quote_char+}[#class-CSV-label-Option+quote_char]: # CSV.new('').quote_char # => "\"" def quote_char parser.quote_character end # :call-seq: # csv.field_size_limit -> integer or nil # # Returns the limit for field size; used for parsing; # see {Option +field_size_limit+}[#class-CSV-label-Option+field_size_limit]: # CSV.new('').field_size_limit # => nil def field_size_limit parser.field_size_limit end # :call-seq: # csv.skip_lines -> regexp or nil # # Returns the \Regexp used to identify comment lines; used for parsing; # see {Option +skip_lines+}[#class-CSV-label-Option+skip_lines]: # CSV.new('').skip_lines # => nil def skip_lines parser.skip_lines end # :call-seq: # csv.converters -> array # # Returns an \Array containing field converters; # see {Field Converters}[#class-CSV-label-Field+Converters]: # csv = CSV.new('') # csv.converters # => [] # csv.convert(:integer) # csv.converters # => [:integer] # csv.convert(proc {|x| x.to_s }) # csv.converters def converters parser_fields_converter.map do |converter| name = Converters.rassoc(converter) name ? name.first : converter end end # :call-seq: # csv.unconverted_fields? -> object # # Returns the value that determines whether unconverted fields are to be # available; used for parsing; # see {Option +unconverted_fields+}[#class-CSV-label-Option+unconverted_fields]: # CSV.new('').unconverted_fields? # => nil def unconverted_fields? parser.unconverted_fields? end # :call-seq: # csv.headers -> object # # Returns the value that determines whether headers are used; used for parsing; # see {Option +headers+}[#class-CSV-label-Option+headers]: # CSV.new('').headers # => nil def headers if @writer @writer.headers else parsed_headers = parser.headers return parsed_headers if parsed_headers raw_headers = @parser_options[:headers] raw_headers = nil if raw_headers == false raw_headers end end # :call-seq: # csv.return_headers? -> true or false # # Returns the value that determines whether headers are to be returned; used for parsing; # see {Option +return_headers+}[#class-CSV-label-Option+return_headers]: # CSV.new('').return_headers? # => false def return_headers? parser.return_headers? end # :call-seq: # csv.write_headers? -> true or false # # Returns the value that determines whether headers are to be written; used for generating; # see {Option +write_headers+}[#class-CSV-label-Option+write_headers]: # CSV.new('').write_headers? # => nil def write_headers? @writer_options[:write_headers] end # :call-seq: # csv.header_converters -> array # # Returns an \Array containing header converters; used for parsing; # see {Header Converters}[#class-CSV-label-Header+Converters]: # CSV.new('').header_converters # => [] def header_converters header_fields_converter.map do |converter| name = HeaderConverters.rassoc(converter) name ? name.first : converter end end # :call-seq: # csv.skip_blanks? -> true or false # # Returns the value that determines whether blank lines are to be ignored; used for parsing; # see {Option +skip_blanks+}[#class-CSV-label-Option+skip_blanks]: # CSV.new('').skip_blanks? # => false def skip_blanks? parser.skip_blanks? end # :call-seq: # csv.force_quotes? -> true or false # # Returns the value that determines whether all output fields are to be quoted; # used for generating; # see {Option +force_quotes+}[#class-CSV-label-Option+force_quotes]: # CSV.new('').force_quotes? # => false def force_quotes? @writer_options[:force_quotes] end # :call-seq: # csv.liberal_parsing? -> true or false # # Returns the value that determines whether illegal input is to be handled; used for parsing; # see {Option +liberal_parsing+}[#class-CSV-label-Option+liberal_parsing]: # CSV.new('').liberal_parsing? # => false def liberal_parsing? parser.liberal_parsing? end # :call-seq: # csv.encoding -> endcoding # # Returns the encoding used for parsing and generating; # see {Character Encodings (M17n or Multilingualization)}[#class-CSV-label-Character+Encodings+-28M17n+or+Multilingualization-29]: # CSV.new('').encoding # => #<Encoding:UTF-8> attr_reader :encoding # :call-seq: # csv.line_no -> integer # # Returns the count of the rows parsed or generated. # # Parsing: # string = "foo,0\nbar,1\nbaz,2\n" # path = 't.csv' # File.write(path, string) # CSV.open(path) do |csv| # csv.each do |row| # p [csv.lineno, row] # end # end # Output: # [1, ["foo", "0"]] # [2, ["bar", "1"]] # [3, ["baz", "2"]] # # Generating: # CSV.generate do |csv| # p csv.lineno; csv << ['foo', 0] # p csv.lineno; csv << ['bar', 1] # p csv.lineno; csv << ['baz', 2] # end # Output: # 0 # 1 # 2 def lineno if @writer @writer.lineno else parser.lineno end end # :call-seq: # csv.line -> array # # Returns the line most recently read: # string = "foo,0\nbar,1\nbaz,2\n" # path = 't.csv' # File.write(path, string) # CSV.open(path) do |csv| # csv.each do |row| # p [csv.lineno, csv.line] # end # end # Output: # [1, "foo,0\n"] # [2, "bar,1\n"] # [3, "baz,2\n"] def line parser.line end ### IO and StringIO Delegation ### extend Forwardable def_delegators :@io, :binmode, :close, :close_read, :close_write, :closed?, :external_encoding, :fcntl, :fileno, :flush, :fsync, :internal_encoding, :isatty, :pid, :pos, :pos=, :reopen, :seek, :string, :sync, :sync=, :tell, :truncate, :tty? def binmode? if @io.respond_to?(:binmode?) @io.binmode? else false end end def flock(*args) raise NotImplementedError unless @io.respond_to?(:flock) @io.flock(*args) end def ioctl(*args) raise NotImplementedError unless @io.respond_to?(:ioctl) @io.ioctl(*args) end def path @io.path if @io.respond_to?(:path) end def stat(*args) raise NotImplementedError unless @io.respond_to?(:stat) @io.stat(*args) end def to_i raise NotImplementedError unless @io.respond_to?(:to_i) @io.to_i end def to_io @io.respond_to?(:to_io) ? @io.to_io : @io end def eof? return false if @eof_error begin parser_enumerator.peek false rescue MalformedCSVError => error @eof_error = error false rescue StopIteration true end end alias_method :eof, :eof? # Rewinds the underlying IO object and resets CSV's lineno() counter. def rewind @parser = nil @parser_enumerator = nil @eof_error = nil @writer.rewind if @writer @io.rewind end ### End Delegation ### # :call-seq: # csv << row -> self # # Appends a row to +self+. # # - Argument +row+ must be an \Array object or a CSV::Row object. # - The output stream must be open for writing. # # --- # # Append Arrays: # CSV.generate do |csv| # csv << ['foo', 0] # csv << ['bar', 1] # csv << ['baz', 2] # end # => "foo,0\nbar,1\nbaz,2\n" # # Append CSV::Rows: # headers = [] # CSV.generate do |csv| # csv << CSV::Row.new(headers, ['foo', 0]) # csv << CSV::Row.new(headers, ['bar', 1]) # csv << CSV::Row.new(headers, ['baz', 2]) # end # => "foo,0\nbar,1\nbaz,2\n" # # Headers in CSV::Row objects are not appended: # headers = ['Name', 'Count'] # CSV.generate do |csv| # csv << CSV::Row.new(headers, ['foo', 0]) # csv << CSV::Row.new(headers, ['bar', 1]) # csv << CSV::Row.new(headers, ['baz', 2]) # end # => "foo,0\nbar,1\nbaz,2\n" # # --- # # Raises an exception if +row+ is not an \Array or \CSV::Row: # CSV.generate do |csv| # # Raises NoMethodError (undefined method `collect' for :foo:Symbol) # csv << :foo # end # # Raises an exception if the output stream is not opened for writing: # path = 't.csv' # File.write(path, '') # File.open(path) do |file| # CSV.open(file) do |csv| # # Raises IOError (not opened for writing) # csv << ['foo', 0] # end # end def <<(row) writer << row self end alias_method :add_row, :<< alias_method :puts, :<< # :call-seq: # convert(converter_name) -> array_of_procs # convert {|field, field_info| ... } -> array_of_procs # # - With no block, installs a field converter (a \Proc). # - With a block, defines and installs a custom field converter. # - Returns the \Array of installed field converters. # # - Argument +converter_name+, if given, should be the name # of an existing field converter. # # See {Field Converters}[#class-CSV-label-Field+Converters]. # --- # # With no block, installs a field converter: # csv = CSV.new('') # csv.convert(:integer) # csv.convert(:float) # csv.convert(:date) # csv.converters # => [:integer, :float, :date] # # --- # # The block, if given, is called for each field: # - Argument +field+ is the field value. # - Argument +field_info+ is a CSV::FieldInfo object # containing details about the field. # # The examples here assume the prior execution of: # string = "foo,0\nbar,1\nbaz,2\n" # path = 't.csv' # File.write(path, string) # # Example giving a block: # csv = CSV.open(path) # csv.convert {|field, field_info| p [field, field_info]; field.upcase } # csv.read # => [["FOO", "0"], ["BAR", "1"], ["BAZ", "2"]] # # Output: # ["foo", #<struct CSV::FieldInfo index=0, line=1, header=nil>] # ["0", #<struct CSV::FieldInfo index=1, line=1, header=nil>] # ["bar", #<struct CSV::FieldInfo index=0, line=2, header=nil>] # ["1", #<struct CSV::FieldInfo index=1, line=2, header=nil>] # ["baz", #<struct CSV::FieldInfo index=0, line=3, header=nil>] # ["2", #<struct CSV::FieldInfo index=1, line=3, header=nil>] # # The block need not return a \String object: # csv = CSV.open(path) # csv.convert {|field, field_info| field.to_sym } # csv.read # => [[:foo, :"0"], [:bar, :"1"], [:baz, :"2"]] # # If +converter_name+ is given, the block is not called: # csv = CSV.open(path) # csv.convert(:integer) {|field, field_info| fail 'Cannot happen' } # csv.read # => [["foo", 0], ["bar", 1], ["baz", 2]] # # --- # # Raises a parse-time exception if +converter_name+ is not the name of a built-in # field converter: # csv = CSV.open(path) # csv.convert(:nosuch) => [nil] # # Raises NoMethodError (undefined method `arity' for nil:NilClass) # csv.read def convert(name = nil, &converter) parser_fields_converter.add_converter(name, &converter) end # :call-seq: # header_convert(converter_name) -> array_of_procs # header_convert {|header, field_info| ... } -> array_of_procs # # - With no block, installs a header converter (a \Proc). # - With a block, defines and installs a custom header converter. # - Returns the \Array of installed header converters. # # - Argument +converter_name+, if given, should be the name # of an existing header converter. # # See {Header Converters}[#class-CSV-label-Header+Converters]. # --- # # With no block, installs a header converter: # csv = CSV.new('') # csv.header_convert(:symbol) # csv.header_convert(:downcase) # csv.header_converters # => [:symbol, :downcase] # # --- # # The block, if given, is called for each header: # - Argument +header+ is the header value. # - Argument +field_info+ is a CSV::FieldInfo object # containing details about the header. # # The examples here assume the prior execution of: # string = "Name,Value\nfoo,0\nbar,1\nbaz,2\n" # path = 't.csv' # File.write(path, string) # # Example giving a block: # csv = CSV.open(path, headers: true) # csv.header_convert {|header, field_info| p [header, field_info]; header.upcase } # table = csv.read # table # => #<CSV::Table mode:col_or_row row_count:4> # table.headers # => ["NAME", "VALUE"] # # Output: # ["Name", #<struct CSV::FieldInfo index=0, line=1, header=nil>] # ["Value", #<struct CSV::FieldInfo index=1, line=1, header=nil>] # The block need not return a \String object: # csv = CSV.open(path, headers: true) # csv.header_convert {|header, field_info| header.to_sym } # table = csv.read # table.headers # => [:Name, :Value] # # If +converter_name+ is given, the block is not called: # csv = CSV.open(path, headers: true) # csv.header_convert(:downcase) {|header, field_info| fail 'Cannot happen' } # table = csv.read # table.headers # => ["name", "value"] # --- # # Raises a parse-time exception if +converter_name+ is not the name of a built-in # field converter: # csv = CSV.open(path, headers: true) # csv.header_convert(:nosuch) # # Raises NoMethodError (undefined method `arity' for nil:NilClass) # csv.read def header_convert(name = nil, &converter) header_fields_converter.add_converter(name, &converter) end include Enumerable # :call-seq: # csv.each -> enumerator # csv.each {|row| ...} # # Calls the block with each successive row. # The data source must be opened for reading. # # Without headers: # string = "foo,0\nbar,1\nbaz,2\n" # csv = CSV.new(string) # csv.each do |row| # p row # end # Output: # ["foo", "0"] # ["bar", "1"] # ["baz", "2"] # # With headers: # string = "Name,Value\nfoo,0\nbar,1\nbaz,2\n" # csv = CSV.new(string, headers: true) # csv.each do |row| # p row # end # Output: # <CSV::Row "Name":"foo" "Value":"0"> # <CSV::Row "Name":"bar" "Value":"1"> # <CSV::Row "Name":"baz" "Value":"2"> # # --- # # Raises an exception if the source is not opened for reading: # string = "foo,0\nbar,1\nbaz,2\n" # csv = CSV.new(string) # csv.close # # Raises IOError (not opened for reading) # csv.each do |row| # p row # end def each(&block) parser_enumerator.each(&block) end # :call-seq: # csv.read -> array or csv_table # # Forms the remaining rows from +self+ into: # - A CSV::Table object, if headers are in use. # - An \Array of Arrays, otherwise. # # The data source must be opened for reading. # # Without headers: # string = "foo,0\nbar,1\nbaz,2\n" # path = 't.csv' # File.write(path, string) # csv = CSV.open(path) # csv.read # => [["foo", "0"], ["bar", "1"], ["baz", "2"]] # # With headers: # string = "Name,Value\nfoo,0\nbar,1\nbaz,2\n" # path = 't.csv' # File.write(path, string) # csv = CSV.open(path, headers: true) # csv.read # => #<CSV::Table mode:col_or_row row_count:4> # # --- # # Raises an exception if the source is not opened for reading: # string = "foo,0\nbar,1\nbaz,2\n" # csv = CSV.new(string) # csv.close # # Raises IOError (not opened for reading) # csv.read def read rows = to_a if parser.use_headers? Table.new(rows, headers: parser.headers) else rows end end alias_method :readlines, :read # :call-seq: # csv.header_row? -> true or false # # Returns +true+ if the next row to be read is a header row\; # +false+ otherwise. # # Without headers: # string = "foo,0\nbar,1\nbaz,2\n" # csv = CSV.new(string) # csv.header_row? # => false # # With headers: # string = "Name,Value\nfoo,0\nbar,1\nbaz,2\n" # csv = CSV.new(string, headers: true) # csv.header_row? # => true # csv.shift # => #<CSV::Row "Name":"foo" "Value":"0"> # csv.header_row? # => false # # --- # # Raises an exception if the source is not opened for reading: # string = "foo,0\nbar,1\nbaz,2\n" # csv = CSV.new(string) # csv.close # # Raises IOError (not opened for reading) # csv.header_row? def header_row? parser.header_row? end # :call-seq: # csv.shift -> array, csv_row, or nil # # Returns the next row of data as: # - An \Array if no headers are used. # - A CSV::Row object if headers are used. # # The data source must be opened for reading. # # Without headers: # string = "foo,0\nbar,1\nbaz,2\n" # csv = CSV.new(string) # csv.shift # => ["foo", "0"] # csv.shift # => ["bar", "1"] # csv.shift # => ["baz", "2"] # csv.shift # => nil # # With headers: # string = "Name,Value\nfoo,0\nbar,1\nbaz,2\n" # csv = CSV.new(string, headers: true) # csv.shift # => #<CSV::Row "Name":"foo" "Value":"0"> # csv.shift # => #<CSV::Row "Name":"bar" "Value":"1"> # csv.shift # => #<CSV::Row "Name":"baz" "Value":"2"> # csv.shift # => nil # # --- # # Raises an exception if the source is not opened for reading: # string = "foo,0\nbar,1\nbaz,2\n" # csv = CSV.new(string) # csv.close # # Raises IOError (not opened for reading) # csv.shift def shift if @eof_error eof_error, @eof_error = @eof_error, nil raise eof_error end begin parser_enumerator.next rescue StopIteration nil end end alias_method :gets, :shift alias_method :readline, :shift # :call-seq: # csv.inspect -> string # # Returns a \String showing certain properties of +self+: # string = "Name,Value\nfoo,0\nbar,1\nbaz,2\n" # csv = CSV.new(string, headers: true) # s = csv.inspect # s # => "#<CSV io_type:StringIO encoding:UTF-8 lineno:0 col_sep:\",\" row_sep:\"\\n\" quote_char:\"\\\"\" headers:true>" def inspect str = ["#<", self.class.to_s, " io_type:"] # show type of wrapped IO if @io == $stdout then str << "$stdout" elsif @io == $stdin then str << "$stdin" elsif @io == $stderr then str << "$stderr" else str << @io.class.to_s end # show IO.path(), if available if @io.respond_to?(:path) and (p = @io.path) str << " io_path:" << p.inspect end # show encoding str << " encoding:" << @encoding.name # show other attributes ["lineno", "col_sep", "row_sep", "quote_char"].each do |attr_name| if a = __send__(attr_name) str << " " << attr_name << ":" << a.inspect end end ["skip_blanks", "liberal_parsing"].each do |attr_name| if a = __send__("#{attr_name}?") str << " " << attr_name << ":" << a.inspect end end _headers = headers str << " headers:" << _headers.inspect if _headers str << ">" begin str.join('') rescue # any encoding error str.map do |s| e = Encoding::Converter.asciicompat_encoding(s.encoding) e ? s.encode(e) : s.force_encoding("ASCII-8BIT") end.join('') end end private def determine_encoding(encoding, internal_encoding) # honor the IO encoding if we can, otherwise default to ASCII-8BIT io_encoding = raw_encoding return io_encoding if io_encoding return Encoding.find(internal_encoding) if internal_encoding if encoding encoding, = encoding.split(":", 2) if encoding.is_a?(String) return Encoding.find(encoding) end Encoding.default_internal || Encoding.default_external end def normalize_converters(converters) converters ||= [] unless converters.is_a?(Array) converters = [converters] end converters.collect do |converter| case converter when Proc # custom code block [nil, converter] else # by name [converter, nil] end end end # # Processes +fields+ with <tt>@converters</tt>, or <tt>@header_converters</tt> # if +headers+ is passed as +true+, returning the converted field set. Any # converter that changes the field into something other than a String halts # the pipeline of conversion for that field. This is primarily an efficiency # shortcut. # def convert_fields(fields, headers = false) if headers header_fields_converter.convert(fields, nil, 0) else parser_fields_converter.convert(fields, @headers, lineno) end end # # Returns the encoding of the internal IO object. # def raw_encoding if @io.respond_to? :internal_encoding @io.internal_encoding || @io.external_encoding elsif @io.respond_to? :encoding @io.encoding else nil end end def parser_fields_converter @parser_fields_converter ||= build_parser_fields_converter end def build_parser_fields_converter specific_options = { builtin_converters: Converters, } options = @base_fields_converter_options.merge(specific_options) build_fields_converter(@initial_converters, options) end def header_fields_converter @header_fields_converter ||= build_header_fields_converter end def build_header_fields_converter specific_options = { builtin_converters: HeaderConverters, accept_nil: true, } options = @base_fields_converter_options.merge(specific_options) build_fields_converter(@initial_header_converters, options) end def writer_fields_converter @writer_fields_converter ||= build_writer_fields_converter end def build_writer_fields_converter build_fields_converter(@initial_write_converters, @write_fields_converter_options) end def build_fields_converter(initial_converters, options) fields_converter = FieldsConverter.new(options) normalize_converters(initial_converters).each do |name, converter| fields_converter.add_converter(name, &converter) end fields_converter end def parser @parser ||= Parser.new(@io, parser_options) end def parser_options @parser_options.merge(header_fields_converter: header_fields_converter, fields_converter: parser_fields_converter) end def parser_enumerator @parser_enumerator ||= parser.parse end def writer @writer ||= Writer.new(@io, writer_options) end def writer_options @writer_options.merge(header_fields_converter: header_fields_converter, fields_converter: writer_fields_converter) end end # Passes +args+ to CSV::instance. # # CSV("CSV,data").read # #=> [["CSV", "data"]] # # If a block is given, the instance is passed the block and the return value # becomes the return value of the block. # # CSV("CSV,data") { |c| # c.read.any? { |a| a.include?("data") } # } #=> true # # CSV("CSV,data") { |c| # c.read.any? { |a| a.include?("zombies") } # } #=> false # def CSV(*args, &block) CSV.instance(*args, &block) end require_relative "csv/version" require_relative "csv/core_ext/array" require_relative "csv/core_ext/string"