JezK
Edit File: row.rb
# frozen_string_literal: true require "forwardable" class CSV # # A CSV::Row is part Array and part Hash. It retains an order for the fields # and allows duplicates just as an Array would, but also allows you to access # fields by name just as you could if they were in a Hash. # # All rows returned by CSV will be constructed from this class, if header row # processing is activated. # class Row # # Constructs a new CSV::Row from +headers+ and +fields+, which are expected # to be Arrays. If one Array is shorter than the other, it will be padded # with +nil+ objects. # # The optional +header_row+ parameter can be set to +true+ to indicate, via # CSV::Row.header_row?() and CSV::Row.field_row?(), that this is a header # row. Otherwise, the row assumes to be a field row. # # A CSV::Row object supports the following Array methods through delegation: # # * empty?() # * length() # * size() # def initialize(headers, fields, header_row = false) @header_row = header_row headers.each { |h| h.freeze if h.is_a? String } # handle extra headers or fields @row = if headers.size >= fields.size headers.zip(fields) else fields.zip(headers).each(&:reverse!) end end # Internal data format used to compare equality. attr_reader :row protected :row ### Array Delegation ### extend Forwardable def_delegators :@row, :empty?, :length, :size def initialize_copy(other) super_return_value = super @row = @row.collect(&:dup) super_return_value end # :call-seq: # row.header_row? -> true or false # # Returns +true+ if this is a header row, +false+ otherwise. def header_row? @header_row end # :call-seq: # row.field_row? -> true or false # # Returns +true+ if this is a field row, +false+ otherwise. def field_row? not header_row? end # :call-seq: # row.headers # # Returns the headers for this row: # source = "Name,Value\nfoo,0\nbar,1\nbaz,2\n" # table = CSV.parse(source, headers: true) # row = table.first # row.headers # => ["Name", "Value"] def headers @row.map(&:first) end # :call-seq: # field(index) # field(header) # field(header, offset) # # Returns the field value for the given +index+ or +header+. # # --- # # Fetch field value by \Integer index: # source = "Name,Value\nfoo,0\nbar,1\nbaz,2\n" # table = CSV.parse(source, headers: true) # row = table[0] # row.field(0) # => "foo" # row.field(1) # => "bar" # # Counts backward from the last column if +index+ is negative: # row.field(-1) # => "0" # row.field(-2) # => "foo" # # Returns +nil+ if +index+ is out of range: # row.field(2) # => nil # row.field(-3) # => nil # # --- # # Fetch field value by header (first found): # source = "Name,Name,Name\nFoo,Bar,Baz\n" # table = CSV.parse(source, headers: true) # row = table[0] # row.field('Name') # => "Foo" # # Fetch field value by header, ignoring +offset+ leading fields: # source = "Name,Name,Name\nFoo,Bar,Baz\n" # table = CSV.parse(source, headers: true) # row = table[0] # row.field('Name', 2) # => "Baz" # # Returns +nil+ if the header does not exist. def field(header_or_index, minimum_index = 0) # locate the pair finder = (header_or_index.is_a?(Integer) || header_or_index.is_a?(Range)) ? :[] : :assoc pair = @row[minimum_index..-1].public_send(finder, header_or_index) # return the field if we have a pair if pair.nil? nil else header_or_index.is_a?(Range) ? pair.map(&:last) : pair.last end end alias_method :[], :field # # :call-seq: # fetch(header) # fetch(header, default) # fetch(header) {|row| ... } # # Returns the field value as specified by +header+. # # --- # # With the single argument +header+, returns the field value # for that header (first found): # source = "Name,Name,Name\nFoo,Bar,Baz\n" # table = CSV.parse(source, headers: true) # row = table[0] # row.fetch('Name') # => "Foo" # # Raises exception +KeyError+ if the header does not exist. # # --- # # With arguments +header+ and +default+ given, # returns the field value for the header (first found) # if the header exists, otherwise returns +default+: # source = "Name,Name,Name\nFoo,Bar,Baz\n" # table = CSV.parse(source, headers: true) # row = table[0] # row.fetch('Name', '') # => "Foo" # row.fetch(:nosuch, '') # => "" # # --- # # With argument +header+ and a block given, # returns the field value for the header (first found) # if the header exists; otherwise calls the block # and returns its return value: # source = "Name,Name,Name\nFoo,Bar,Baz\n" # table = CSV.parse(source, headers: true) # row = table[0] # row.fetch('Name') {|header| fail 'Cannot happen' } # => "Foo" # row.fetch(:nosuch) {|header| "Header '#{header} not found'" } # => "Header 'nosuch not found'" def fetch(header, *varargs) raise ArgumentError, "Too many arguments" if varargs.length > 1 pair = @row.assoc(header) if pair pair.last else if block_given? yield header elsif varargs.empty? raise KeyError, "key not found: #{header}" else varargs.first end end end # :call-seq: # row.has_key?(header) # # Returns +true+ if there is a field with the given +header+, # +false+ otherwise. def has_key?(header) !!@row.assoc(header) end alias_method :include?, :has_key? alias_method :key?, :has_key? alias_method :member?, :has_key? alias_method :header?, :has_key? # # :call-seq: # row[index] = value -> value # row[header, offset] = value -> value # row[header] = value -> value # # Assigns the field value for the given +index+ or +header+; # returns +value+. # # --- # # Assign field value by \Integer index: # source = "Name,Value\nfoo,0\nbar,1\nbaz,2\n" # table = CSV.parse(source, headers: true) # row = table[0] # row[0] = 'Bat' # row[1] = 3 # row # => #<CSV::Row "Name":"Bat" "Value":3> # # Counts backward from the last column if +index+ is negative: # row[-1] = 4 # row[-2] = 'Bam' # row # => #<CSV::Row "Name":"Bam" "Value":4> # # Extends the row with <tt>nil:nil</tt> if positive +index+ is not in the row: # row[4] = 5 # row # => #<CSV::Row "Name":"bad" "Value":4 nil:nil nil:nil nil:5> # # Raises IndexError if negative +index+ is too small (too far from zero). # # --- # # Assign field value by header (first found): # source = "Name,Name,Name\nFoo,Bar,Baz\n" # table = CSV.parse(source, headers: true) # row = table[0] # row['Name'] = 'Bat' # row # => #<CSV::Row "Name":"Bat" "Name":"Bar" "Name":"Baz"> # # Assign field value by header, ignoring +offset+ leading fields: # source = "Name,Name,Name\nFoo,Bar,Baz\n" # table = CSV.parse(source, headers: true) # row = table[0] # row['Name', 2] = 4 # row # => #<CSV::Row "Name":"Foo" "Name":"Bar" "Name":4> # # Append new field by (new) header: # source = "Name,Value\nfoo,0\nbar,1\nbaz,2\n" # table = CSV.parse(source, headers: true) # row = table[0] # row['New'] = 6 # row# => #<CSV::Row "Name":"foo" "Value":"0" "New":6> def []=(*args) value = args.pop if args.first.is_a? Integer if @row[args.first].nil? # extending past the end with index @row[args.first] = [nil, value] @row.map! { |pair| pair.nil? ? [nil, nil] : pair } else # normal index assignment @row[args.first][1] = value end else index = index(*args) if index.nil? # appending a field self << [args.first, value] else # normal header assignment @row[index][1] = value end end end # # :call-seq: # row << [header, value] -> self # row << hash -> self # row << value -> self # # Adds a field to +self+; returns +self+: # # If the argument is a 2-element \Array <tt>[header, value]</tt>, # a field is added with the given +header+ and +value+: # source = "Name,Name,Name\nFoo,Bar,Baz\n" # table = CSV.parse(source, headers: true) # row = table[0] # row << ['NAME', 'Bat'] # row # => #<CSV::Row "Name":"Foo" "Name":"Bar" "Name":"Baz" "NAME":"Bat"> # # If the argument is a \Hash, each <tt>key-value</tt> pair is added # as a field with header +key+ and value +value+. # source = "Name,Name,Name\nFoo,Bar,Baz\n" # table = CSV.parse(source, headers: true) # row = table[0] # row << {NAME: 'Bat', name: 'Bam'} # row # => #<CSV::Row "Name":"Foo" "Name":"Bar" "Name":"Baz" NAME:"Bat" name:"Bam"> # # Otherwise, the given +value+ is added as a field with no header. # source = "Name,Name,Name\nFoo,Bar,Baz\n" # table = CSV.parse(source, headers: true) # row = table[0] # row << 'Bag' # row # => #<CSV::Row "Name":"Foo" "Name":"Bar" "Name":"Baz" nil:"Bag"> def <<(arg) if arg.is_a?(Array) and arg.size == 2 # appending a header and name @row << arg elsif arg.is_a?(Hash) # append header and name pairs arg.each { |pair| @row << pair } else # append field value @row << [nil, arg] end self # for chaining end # :call-seq: # row.push(*values) ->self # # Appends each of the given +values+ to +self+ as a field; returns +self+: # source = "Name,Name,Name\nFoo,Bar,Baz\n" # table = CSV.parse(source, headers: true) # row = table[0] # row.push('Bat', 'Bam') # row # => #<CSV::Row "Name":"Foo" "Name":"Bar" "Name":"Baz" nil:"Bat" nil:"Bam"> def push(*args) args.each { |arg| self << arg } self # for chaining end # # :call-seq: # delete(index) -> [header, value] or nil # delete(header) -> [header, value] or empty_array # delete(header, offset) -> [header, value] or empty_array # # Removes a specified field from +self+; returns the 2-element \Array # <tt>[header, value]</tt> if the field exists. # # If an \Integer argument +index+ is given, # removes and returns the field at offset +index+, # or returns +nil+ if the field does not exist: # source = "Name,Name,Name\nFoo,Bar,Baz\n" # table = CSV.parse(source, headers: true) # row = table[0] # row.delete(1) # => ["Name", "Bar"] # row.delete(50) # => nil # # Otherwise, if the single argument +header+ is given, # removes and returns the first-found field with the given header, # of returns a new empty \Array if the field does not exist: # source = "Name,Name,Name\nFoo,Bar,Baz\n" # table = CSV.parse(source, headers: true) # row = table[0] # row.delete('Name') # => ["Name", "Foo"] # row.delete('NAME') # => [] # # If argument +header+ and \Integer argument +offset+ are given, # removes and returns the first-found field with the given header # whose +index+ is at least as large as +offset+: # source = "Name,Name,Name\nFoo,Bar,Baz\n" # table = CSV.parse(source, headers: true) # row = table[0] # row.delete('Name', 1) # => ["Name", "Bar"] # row.delete('NAME', 1) # => [] def delete(header_or_index, minimum_index = 0) if header_or_index.is_a? Integer # by index @row.delete_at(header_or_index) elsif i = index(header_or_index, minimum_index) # by header @row.delete_at(i) else [ ] end end # :call-seq: # row.delete_if {|header, value| ... } -> self # # Removes fields from +self+ as selected by the block; returns +self+. # # Removes each field for which the block returns a truthy value: # source = "Name,Name,Name\nFoo,Bar,Baz\n" # table = CSV.parse(source, headers: true) # row = table[0] # row.delete_if {|header, value| value.start_with?('B') } # => true # row # => #<CSV::Row "Name":"Foo"> # row.delete_if {|header, value| header.start_with?('B') } # => false # # If no block is given, returns a new Enumerator: # row.delete_if # => #<Enumerator: #<CSV::Row "Name":"Foo">:delete_if> def delete_if(&block) return enum_for(__method__) { size } unless block_given? @row.delete_if(&block) self # for chaining end # :call-seq: # self.fields(*specifiers) # # Returns field values per the given +specifiers+, which may be any mixture of: # - \Integer index. # - \Range of \Integer indexes. # - 2-element \Array containing a header and offset. # - Header. # - \Range of headers. # # For +specifier+ in one of the first four cases above, # returns the result of <tt>self.field(specifier)</tt>; see #field. # # Although there may be any number of +specifiers+, # the examples here will illustrate one at a time. # # When the specifier is an \Integer +index+, # returns <tt>self.field(index)</tt>L # source = "Name,Name,Name\nFoo,Bar,Baz\n" # table = CSV.parse(source, headers: true) # row = table[0] # row.fields(1) # => ["Bar"] # # When the specifier is a \Range of \Integers +range+, # returns <tt>self.field(range)</tt>: # row.fields(1..2) # => ["Bar", "Baz"] # # When the specifier is a 2-element \Array +array+, # returns <tt>self.field(array)</tt>L # row.fields('Name', 1) # => ["Foo", "Bar"] # # When the specifier is a header +header+, # returns <tt>self.field(header)</tt>L # row.fields('Name') # => ["Foo"] # # When the specifier is a \Range of headers +range+, # forms a new \Range +new_range+ from the indexes of # <tt>range.start</tt> and <tt>range.end</tt>, # and returns <tt>self.field(new_range)</tt>: # source = "Name,NAME,name\nFoo,Bar,Baz\n" # table = CSV.parse(source, headers: true) # row = table[0] # row.fields('Name'..'NAME') # => ["Foo", "Bar"] # # Returns all fields if no argument given: # row.fields # => ["Foo", "Bar", "Baz"] def fields(*headers_and_or_indices) if headers_and_or_indices.empty? # return all fields--no arguments @row.map(&:last) else # or work like values_at() all = [] headers_and_or_indices.each do |h_or_i| if h_or_i.is_a? Range index_begin = h_or_i.begin.is_a?(Integer) ? h_or_i.begin : index(h_or_i.begin) index_end = h_or_i.end.is_a?(Integer) ? h_or_i.end : index(h_or_i.end) new_range = h_or_i.exclude_end? ? (index_begin...index_end) : (index_begin..index_end) all.concat(fields.values_at(new_range)) else all << field(*Array(h_or_i)) end end return all end end alias_method :values_at, :fields # # :call-seq: # index( header ) # index( header, offset ) # # This method will return the index of a field with the provided +header+. # The +offset+ can be used to locate duplicate header names, as described in # CSV::Row.field(). # def index(header, minimum_index = 0) # find the pair index = headers[minimum_index..-1].index(header) # return the index at the right offset, if we found one index.nil? ? nil : index + minimum_index end # # Returns +true+ if +data+ matches a field in this row, and +false+ # otherwise. # def field?(data) fields.include? data end include Enumerable # # Yields each pair of the row as header and field tuples (much like # iterating over a Hash). This method returns the row for chaining. # # If no block is given, an Enumerator is returned. # # Support for Enumerable. # def each(&block) return enum_for(__method__) { size } unless block_given? @row.each(&block) self # for chaining end alias_method :each_pair, :each # # Returns +true+ if this row contains the same headers and fields in the # same order as +other+. # def ==(other) return @row == other.row if other.is_a? CSV::Row @row == other end # :call-seq: # row.to_h -> hash # # Returns the new \Hash formed by adding each header-value pair in +self+ # as a key-value pair in the \Hash. # source = "Name,Value\nfoo,0\nbar,1\nbaz,2\n" # table = CSV.parse(source, headers: true) # row = table[0] # row.to_h # => {"Name"=>"foo", "Value"=>"0"} # # Header order is preserved, but repeated headers are ignored: # source = "Name,Name,Name\nFoo,Bar,Baz\n" # table = CSV.parse(source, headers: true) # row = table[0] # row.to_h # => {"Name"=>"Foo"} def to_h hash = {} each do |key, _value| hash[key] = self[key] unless hash.key?(key) end hash end alias_method :to_hash, :to_h alias_method :to_ary, :to_a # :call-seq: # row.to_csv -> csv_string # # Returns the row as a \CSV String. Headers are not included: # source = "Name,Value\nfoo,0\nbar,1\nbaz,2\n" # table = CSV.parse(source, headers: true) # row = table[0] # row.to_csv # => "foo,0\n" def to_csv(**options) fields.to_csv(**options) end alias_method :to_s, :to_csv # :call-seq: # row.dig(index_or_header, *identifiers) -> object # # Finds and returns the object in nested object that is specified # by +index_or_header+ and +specifiers+. # # The nested objects may be instances of various classes. # See {Dig Methods}[https://docs.ruby-lang.org/en/master/doc/dig_methods_rdoc.html]. # # Examples: # source = "Name,Value\nfoo,0\nbar,1\nbaz,2\n" # table = CSV.parse(source, headers: true) # row = table[0] # row.dig(1) # => "0" # row.dig('Value') # => "0" # row.dig(5) # => nil def dig(index_or_header, *indexes) value = field(index_or_header) if value.nil? nil elsif indexes.empty? value else unless value.respond_to?(:dig) raise TypeError, "#{value.class} does not have \#dig method" end value.dig(*indexes) end end # :call-seq: # row.inspect -> string # # Returns an ASCII-compatible \String showing: # - Class \CSV::Row. # - Header-value pairs. # Example: # source = "Name,Value\nfoo,0\nbar,1\nbaz,2\n" # table = CSV.parse(source, headers: true) # row = table[0] # row.inspect # => "#<CSV::Row \"Name\":\"foo\" \"Value\":\"0\">" def inspect str = ["#<", self.class.to_s] each do |header, field| str << " " << (header.is_a?(Symbol) ? header.to_s : header.inspect) << ":" << field.inspect end 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 end end