require "tty-screen"
require "unicode/display_width"
module Tabulo
# Represents a table primarily intended for "pretty-printing" in a fixed-width font.
#
# A Table is also an Enumerable, of which each element is a {Row}.
class Table
include Enumerable
# @!visibility public
DEFAULT_BORDER = :ascii
# @!visibility public
DEFAULT_COLUMN_WIDTH = 12
# @!visibility public
DEFAULT_COLUMN_PADDING = 1
# @!visibility public
DEFAULT_TRUNCATION_INDICATOR = "~"
# @!visibility private
PADDING_CHARACTER = " "
# @!visibility private
attr_reader :column_registry
# @return [Enumerable] the underlying enumerable from which the table derives its data
attr_accessor :sources
# @param [Enumerable] sources the underlying Enumerable from which the table will derive its data
# @param [Array[Symbol]] columns Specifies the initial columns. The Symbols provided must
# be unique. Each element of the Array will be used to create a column whose content is
# created by calling the corresponding method on each element of sources. Note
# the {#add_column} method is a much more flexible way to set up columns on the table.
# @param [:left, :right, :center, :auto] align_body Determines the alignment of body cell
# (i.e. non-header) content within columns in this Table. Can be overridden for individual columns
# using the align_body option passed to {#add_column}. If passed :auto,
# alignment is determined by cell content, with numbers aligned right, booleans
# center-aligned, and other values left-aligned.
# @param [:left, :right, :center] align_header Determines the alignment of header text
# for columns in this Table. Can be overridden for individual columns using the
# align_header option passed to {#add_column}
# @param [:left, :right, :center] align_header Determines the alignment of the table
# title, if present.
# @param [:ascii, :markdown, :modern, :blank, nil] border Determines the characters used
# for the Table border, including both the characters around the outside of table, and the lines drawn
# within the table to separate columns from each other and the header row from the Table body.
# If nil, then the value of {DEFAULT_BORDER} will be used.
# Possible values are:
# - `:ascii` Uses ASCII characters only
# - `:markdown` Produces a GitHub-flavoured Markdown table. Note: Using the `title`
# option in combination with this border type will cause the rendered
# table not to be valid Markdown, since Markdown engines do not generally
# support adding a caption element (i.e. title) to tables.
# - `:modern` Uses non-ASCII Unicode characters to render a border with smooth continuous lines
# - `:blank` No border characters are rendered
# - `:reduced_ascii` Like `:ascii`, but without left or right borders, and with internal vertical
# borders and intersection characters consisting of whitespace only
# - `:reduced_modern` Like `:modern`, but without left or right borders, and with internal vertical
# borders and intersection characters consisting of whitespace only
# - `:classic` Like `:ascii`, but does not have a horizontal line at the bottom of the
# table. This reproduces the default behaviour in `tabulo` v1.
# @param [nil, #to_proc] border_styler A lambda or other callable object taking
# a single parameter, representing a section of the table's borders (which for this purpose
# include any horizontal and vertical lines inside the table), and returning a string.
# If passed nil, then no additional styling will be applied to borders. If passed a
# callable, then that callable will be called for each border section, with the
# resulting string rendered in place of that border. The extra width of the string returned by the
# border_styler is not taken into consideration by the internal table rendering calculations
# Thus it can be used to apply ANSI escape codes to border characters, to colour the borders
# for example, without breaking the table formatting.
# @param [nil, Integer, Array] column_padding Determines the amount of blank space with which to pad
# either side of each column. If passed an Integer, then the given amount of padding is
# applied to each side of each column. If passed a two-element Array, then the first element of the
# Array indicates the amount of padding to apply to the left of each column, and the second
# element indicates the amount to apply to the right. This setting can be overridden for
# individual columns using the `padding` option of {#add_column}.
# @param [Integer, nil] column_width The default column width for columns in this
# table, not excluding padding. If nil, then {DEFAULT_COLUMN_WIDTH} will be used.
# @param [nil, #to_proc] formatter The default formatter for columns in this
# table. See `formatter` option of {#add_column} for details.
# @param [:start, nil, Integer] header_frequency (:start) Controls the display of column headers.
# If passed :start, headers will be shown at the top of the table only. If passed nil,
# headers will not be shown. If passed an Integer N (> 0), headers will be shown at the top of the table,
# then repeated every N rows.
# @param [nil, #to_proc] header_styler The default header styler for columns in this
# table. See `header_styler` option of {#add_column} for details.
# @param [nil, Integer] row_divider_frequency Controls the display of horizontal row dividers within
# the table body. If passed nil, dividers will not be shown. If passed an Integer N (> 0),
# dividers will be shown after every N rows. The characters used to form the dividers are
# determined by the `border` option, and are the same as those used to form the bottom edge of the
# header row.
# @param [nil, #to_proc] styler The default styler for columns in this table. See `styler`
# option of {#add_column} for details.
# @param [nil, String] title If passed a String, will arrange for a title to be shown at the top
# of the table. Note: If the `border` option is set to `:markdown`, adding a title to the table
# will cause it to cease being valid Markdown when rendered, since Markdown engines do not generally
# support adding a caption element (i.e. title) to tables.
# @param [nil, #to_proc] title_styler A lambda or other callable object that will
# determine the colors or other styling applied to the table title. Can be passed
# nil, or can be passed a callable that takes either 1 or 2 parametes:
# * If passed nil, then no additional styling will be applied to the title.
# * If passed a callable, then that callable will be called for each line of
# the title, and the resulting string rendered in place of that line.
# The extra width of the string returned by the title_styler is not taken into
# consideration by the internal table and cell width calculations involved in rendering the
# table. Thus it can be used to apply ANSI escape codes to title content, to color the
# content for example, without breaking the table formatting.
# * If the passed callable takes 1 parameter, then the first parameter is a string
# representing a single line within the title. For example, if the title
# is wrapped over three lines, then the title_styler will be called
# three times, once for each line of content.
# * If the passed callable takes 2 parameters, then the first parameter is as above, and the
# second parameter is an Integer representing the index of the line within the
# title that is currently being styled. For example, if the title is wrapped over 3
# lines, then the callable will be called first with a line index of 0, to style the first line,
# then with a line index of 1, to style the second line, and finally with a line index of 2, for
# the third and final wrapped line of the cell.
#
# @param [nil, String] truncation_indicator Determines the character used to indicate that a
# cell's content has been truncated. If omitted or passed nil,
# defaults to {DEFAULT_TRUNCATION_INDICATOR}. If passed something other than nil or
# a single-character String, raises {InvalidTruncationIndicatorError}.
# @param [Symbol] wrap_preserve Specifies what unit of text the wrapping mechanism will try to
# preserve intact when wrapping column content when the column width is reached:
# * If passed `:rune` (the default), then it will wrap at the "character" level (approximately
# speaking, the Unicode grapheme cluster level). This means the maximum number of what
# readers usually think of as "characters" will be fit on each line, within the column's allocated
# width, before contininuing to a new line, even if it means splitting a word in the middle.
# * If passed `:word`, then it will wrap in such a way as to avoid splitting words, where
# "words" are defined as units of text separated by spaces or dashes (hyphens, m-dashes and
# n-dashes). Whitespace will be used to pad lines as required. Already-hyphenated may will be split
# at the hyphen, however hyphens will not be inserted in non-hyphenated words.
# @param [nil, Integer] wrap_body_cells_to Controls wrapping behaviour for table cells (excluding
# headers), if their content is longer than the column's fixed width. If passed nil, content will
# be wrapped for as many rows as required to accommodate it. If passed an Integer N (> 0), content will be
# wrapped up to N rows and then truncated thereafter.
# headers), if their content is longer than the column's fixed width. If passed nil, content will
# be wrapped for as many rows as required to accommodate it. If passed an Integer N (> 0), content will be
# wrapped up to N rows and then truncated thereafter.
# @param [nil, Integer] wrap_header_cells_to Controls wrapping behaviour for header
# cells if the content thereof is longer than the column's fixed width. If passed nil (default),
# content will be wrapped for as many rows as required to accommodate it. If passed an Integer N (> 0),
# content will be wrapped up to N rows and then truncated thereafter.
# @return [Table] a new {Table}
# @raise [InvalidColumnLabelError] if non-unique Symbols are provided to columns.
# @raise [InvalidBorderError] if invalid option passed to `border` parameter.
def initialize(sources, *columns, align_body: :auto, align_header: :center, align_title: :center,
border: nil, border_styler: nil, column_padding: nil, column_width: nil, formatter: :to_s.to_proc,
header_frequency: :start, header_styler: nil, row_divider_frequency: nil, styler: nil,
title: nil, title_styler: nil, truncation_indicator: nil, wrap_preserve: :rune, wrap_body_cells_to: nil,
wrap_header_cells_to: nil)
@sources = sources
@align_body = align_body
@align_header = align_header
@align_title = align_title
@border = (border || DEFAULT_BORDER)
@border_styler = border_styler
@border_instance = Border.from(@border, @border_styler)
@column_padding = (column_padding || DEFAULT_COLUMN_PADDING)
@left_column_padding, @right_column_padding =
(Array === @column_padding ? @column_padding : [@column_padding, @column_padding])
@column_width = (column_width || DEFAULT_COLUMN_WIDTH)
@formatter = formatter
@header_frequency = header_frequency
@header_styler = header_styler
@row_divider_frequency = row_divider_frequency
@styler = styler
@title = title
@title_styler = title_styler
@truncation_indicator = validate_character(truncation_indicator,
DEFAULT_TRUNCATION_INDICATOR, InvalidTruncationIndicatorError, "truncation indicator")
@wrap_preserve = wrap_preserve
@wrap_body_cells_to = wrap_body_cells_to
@wrap_header_cells_to = wrap_header_cells_to
@column_registry = { }
columns.each { |item| add_column(item) }
yield self if block_given?
end
# Adds a column to the Table.
#
# @param [Symbol, String, Integer] label A unique identifier for this column, which by
# default will also be used as the column header text (see also the header param). If the
# extractor argument is not also provided, then the label argument should correspond to
# a method to be called on each item in the table sources to provide the content
# for this column. If a String is passed as the label, then it will be converted to
# a Symbol for the purpose of serving as this label.
# @param [:left, :center, :right, :auto, nil] align_body Specifies how the cell body contents
# should be aligned. If nil is passed, then the alignment is determined
# by the Table-level setting passed to the align_body option on Table initialization
# (which itself defaults to :auto). Otherwise this option determines the alignment of
# this column. If :auto is passed, the alignment is determined by the type of the cell
# value, with numbers aligned right, booleans center-aligned, and other values left-aligned.
# Note header text alignment is configured separately using the :align_header param.
# @param [:left, :center, :right, nil] align_header Specifies how the header text
# should be aligned. If nil is passed, then the alignment is determined
# by the Table-level setting passed to the align_header (which itself defaults
# to :center). Otherwise, this option determines the alignment of the header
# content for this column.
# @param [Symbol, String, Integer, nil] before The label of the column before (i.e. to
# the left of) which the new column should inserted. If nil is passed, it will be
# inserted after all other columns. If there is no column with the given label, then an
# {InvalidColumnLabelError} will be raised. A non-Integer labelled column can be identified
# in either String or Symbol form for this purpose.
# @param [#to_proc] formatter A lambda or other callable object that
# will be passed the calculated value of each cell to determine how it should be displayed. This
# is distinct from the extractor and the styler (see below).
# For example, if the extractor for this column generates a Date, then the formatter might format
# that Date in a particular way.
# * If nil is provided, then the callable that was passed to the `formatter` option
# of the table itself on its creation (see {#initialize}) (which itself defaults to
# `:to_s.to_proc`), will be used as the formatter for the column.
# * If a 1-parameter callable is passed, then this callable will be called with the calculated
# value of the cell; it should then return a String, and this String will be displayed as
# the formatted value of the cell.
# * If a 2-parameter callable is passed, then the first parameter represents the calculated
# value of the cell, and the second parameter is a {CellData} instance, containing
# additional information about the cell that may be relevant to what formatting should
# be applied. For example, the {CellData#row_index} attribute can be inspected to determine
# whether the {Cell} is an odd- or even-numbered {Row}, to arrange for different formatting
# to be applied to alternating rows.
# See the documentation for {CellData} for more.
# @param [nil, #to_s] header Text to be displayed in the column header. If passed nil,
# the column's label will also be used as its header text.
# @param [nil, #to_proc] header_styler (nil) A lambda or other callable object that will
# determine the colors or other styling applied to the header content. Can be passed
# nil, or can be passed a callable that takes 1, 2 or 3 parameters:
# * If passed nil, then no additional styling will be applied to the cell content
# (other than what was already applied by the formatter).
# * If passed a callable, then that callable will be called for each line of content within
# the header cell, and the resulting string rendered in place of that line.
# The extra width of the string returned by the header_styler is not taken into
# consideration by the internal table and cell width calculations involved in rendering the
# table. Thus it can be used to apply ANSI escape codes to header cell content, to color the
# cell content for example, without breaking the table formatting.
# * If the passed callable takes 1 parameter, then the first parameter is a string
# representing a single formatted line within the header cell. For example, if the header
# cell content is wrapped over three lines, then the header_styler will be called
# three times for that header cell, once for each line of content.
# * If the passed callable takes 2 parameters, then the first parameter is as above, and the
# second parameter is an Integer representing the positional index of this header's {Column},
# with the leftmost column having index 0, the next having index 1 etc.. This can be
# used, for example, to apply different styles to alternating {Column}s.
# * If the passed callable takes 3 parameters, then the first and second parameters are as above,
# and the third parameter is an Integer representing the index of the line within the
# header cell that is currently being styled. For example, if the cell content is wrapped over 3
# lines, then the callable will be called first with a line index of 0, to style the first line,
# then with a line index of 1, to style the second line, and finally with a line index of 2, for
# the third and final wrapped line of the cell.
#
# Note that if the header content is truncated, then any header_styler will be applied to the
# truncation indicator character as well as to the truncated content.
# @param [nil, Integer, Array] padding Determines the amount of blank space with which to
# pad either side of the column. If passed nil, then the `column_padding` setting of the
# {Table} will determine the column's padding. (See {#initialize}.) Otherwise, this option
# overrides, for this column, the `column_padding` that was set at the table level: if passed an Integer,
# then the given amount of padding is applied to either side of the column; or if passed a two-element Array,
# then the first element of the Array indicates the amount of padding to apply to the left of the column,
# and the second element indicates the amount to apply to the right.
# @param [nil, #to_proc] styler A lambda or other callable object that will determine
# the colors or other styling applied to the formatted value of the cell. Can be passed
# nil, or can be passed a callable that takes either 2 or 3 parameters:
# * If passed nil, then no additional styling will be applied to the cell content
# (other than what was already applied by the formatter).
# * If passed a callable, then that callable will be called for each line of content within
# the cell, and the resulting string rendered in place of that line.
# The styler option differs from the formatter option in that the extra width of the
# string returned by styler is not taken into consideration by the internal table and
# cell width calculations involved in rendering the table. Thus it can be used to apply
# ANSI escape codes to cell content, to color the cell content for example, without
# breaking the table formatting.
# * If the passed callable takes 2 parameters, then the first parameter is the calculated
# value of the cell (prior to the formatter being applied); and the second parameter is
# a string representing a single formatted line within the cell. For example, if the cell
# content is wrapped over three lines, then for that cell, the styler will be called
# three times, once for each line of content within the cell.
# * If the passed callable takes 3 parameters, then the first two parameters are as above,
# and the third parameter is a {CellData} instance, containing additional information
# about the cell that may be relevant to what styles should be applied. For example, the
# {CellData#row_index} attribute can be inspected to determine whether the {Cell} is an
# odd- or even-numbered {Row}, to arrange for different styling to be applied to
# alternating rows. See the documentation for {CellData} for more.
# * If the passed callable takes 4 parameters, then the first three parameters are as above,
# and the fourth parameter is an Integer representing the index of the line within the
# cell that is currently being styled. For example, if the cell content is wrapped over 3
# lines, then the callable will be called first with a line index of 0, to style the first
# line, then with a line index of 1, to style the second line, and finally with a line
# index of 2, to style the third and final wrapped line of the cell.
#
# Note that if the content of a cell is truncated, then the whatever styling is applied by the
# styler to the cell content will also be applied to the truncation indicator character.
# @param [Integer] width Specifies the width of the column, excluding padding. If
# nil, then the column will take the width provided by the `column_width` param
# with which the Table was initialized.
# @param [Symbol] wrap_preserve Specifies how to wrap column content when the column width is reached.
# * If passed `nil`, or not provided, then the value passed to the `wrap_preserve` param of
# {#initialize} will be used.
# * If passed `rune` or word, then the option passed to {#initialize} will be overridden for
# this column. See the documentation under {#initialize} for the behaviour of each option.
# @param [#to_proc] extractor A block or other callable that will be passed each of the {Table}
# sources to determine the value in each cell of this column.
# * If this is not provided, then the column label will be treated as a method to be called on
# each source item to determine each cell's value.
# * If provided a single-parameter callable, then this callable will be passed each of the
# {Table} sources to determine the cell value for each row in this column.
# * If provided a 2-parameter callable, then for each of the {Table} sources, this callable
# will be passed the source, and the row index, to determine the cell value for that row.
# For this purpose, the first body row (not counting the header row) has an index of 0,
# the next an index of 1, etc..
# @raise [InvalidColumnLabelError] if label has already been used for another column in this
# Table. (This is case-sensitive, but is insensitive to whether a String or Symbol is passed
# to the label parameter.)
def add_column(label, align_body: nil, align_header: nil, before: nil, formatter: nil,
header: nil, header_styler: nil, padding: nil, styler: nil, width: nil, wrap_preserve: nil, &extractor)
column_label = normalize_column_label(label)
left_padding, right_padding =
if padding
Array === padding ? padding : [padding, padding]
else
[@left_column_padding, @right_column_padding]
end
if column_registry.include?(column_label)
raise InvalidColumnLabelError, "Column label already used in this table."
end
column = Column.new(
align_body: align_body || @align_body,
align_header: align_header || @align_header,
extractor: extractor || label.to_proc,
formatter: formatter || @formatter,
header: (header || label).to_s,
header_styler: header_styler || @header_styler,
index: column_registry.count,
left_padding: left_padding,
padding_character: PADDING_CHARACTER,
right_padding: right_padding,
styler: styler || @styler,
truncation_indicator: @truncation_indicator,
wrap_preserve: wrap_preserve || @wrap_preserve,
width: width || @column_width,
)
if before == nil
add_column_final(column, column_label)
else
add_column_before(column, column_label, before)
end
end
# Removes the column identifed by the passed label.
#
# @example
# table = Table.new(1..10, :itself, :even?, :odd?)
# table.add_column(:even2, header: "even?") { |n| n.even? }
# table.remove_column(:even2)
# table.remove_column(:odd?)
#
# @param [Symbol, String, Integer] label The unique identifier for the column to be removed,
# corresponding to the label that was passed as the first parameter to {#add_column} (or was
# used in the table initializer) when the column was originally added. For columns that were
# originally added with a String or Symbol label, either a String or Symbol form of that label
# can be passed to {#remove_column}, indifferently. For example, if the label passed to
# {#add_column} had been `"height"`, then that column could be removed by passing either
# `"height"` or `:height` to {#remove_column}. (However, if an Integer was originally passed
# as the label to {#add_column}, then only that same Integer, as an Integer, can be passed to
# {#remove_column} to remove that column.)
# @return [true, false] If the label identifies a column in the table, then the column will be
# removed and true will be returned; otherwise no column will be removed, and false will be returned.
def remove_column(label)
!!column_registry.delete(Integer === label ? label : label.to_sym)
end
# @return [String] a graphical "ASCII" representation of the Table, suitable for
# display in a fixed-width font.
def to_s
if column_registry.any?
bottom_edge = horizontal_rule(:bottom)
rows = map(&:to_s)
bottom_edge.empty? ? Util.join_lines(rows) : Util.join_lines(rows + [bottom_edge])
else
""
end
end
# Calls the given block once for each {Row} in the Table, passing that {Row} as parameter.
#
# @example
# table.each do |row|
# puts row
# end
#
# Note that when printed, the first row will visually include the headers (assuming these
# were not disabled when the Table was initialized).
def each
@sources.each_with_index do |source, index|
header =
if (index == 0) && @header_frequency
:top
elsif (Integer === @header_frequency) && Util.divides?(@header_frequency, index)
:middle
end
show_divider = @row_divider_frequency && (index != 0) && Util.divides?(@row_divider_frequency, index)
yield Row.new(self, source, header: header, divider: show_divider, index: index)
end
end
# @return [String] a graphical representation of the Table column headers formatted with fixed
# width plain text, excluding any horizontal borders above or below.
def formatted_header
cells = get_columns.map(&:header_cell)
format_row(cells, @wrap_header_cells_to)
end
# Produce a horizontal dividing line suitable for printing at the top, bottom or middle
# of the table.
#
# @param [:top, :middle, :bottom, :title_top, :title_bottom] position
# Specifies the position for which the resulting horizontal dividing line is intended to
# be printed. This determines the border characters that are used to construct the line.
# The `:title_top` and `:title_bottom` options are used internally for adding borders
# above and below the table title text.
# @return [String] an "ASCII" graphical representation of a horizontal
# dividing line.
# @example Print a horizontal divider between each pair of rows, and again at the bottom:
#
# table.each_with_index do |row, i|
# puts table.horizontal_rule(:middle) unless i == 0
# puts row
# end
# puts table.horizontal_rule(:bottom)
#
# It may be that `:top`, `:middle` and `:bottom` all look the same. Whether
# this is the case depends on the characters used for the table border.
def horizontal_rule(position = :bottom)
column_widths = get_columns.map { |column| column.width + column.total_padding }
@border_instance.horizontal_rule(column_widths, position)
end
# Resets all the column widths so that each column is *just* wide enough to accommodate
# its header text as well as the formatted content of each its cells for the entire
# collection, together with a single character of padding on either side of the column,
# without any wrapping. In addition, if the table has a title but is not wide enough to
# accommodate (without wrapping) the title text (with a character of padding either side),
# widens the columns roughly evenly until the table as a whole is just wide enough to
# accommodate the title text.
#
# Note that calling this method will cause the entire source Enumerable to
# be traversed and all the column extractors and formatters to be applied in order
# to calculate the required widths.
#
# Note also that this method causes column widths to be fixed as appropriate to the
# formatted cell contents given the state of the source Enumerable at the point it
# is called. If the source Enumerable changes between that point, and the point when
# the Table is printed, then columns will *not* be resized yet again on printing.
#
# @param [nil, Numeric] max_table_width With no args, or if passed :auto,
# stops the total table width (including padding and borders) from expanding beyond the
# bounds of the terminal screen.
# If passed nil, the table width will not be capped.
# Width is deducted from columns if required to achieve this, with one character progressively
# deducted from the width of the widest column until the target is reached. When the
# table is printed, wrapping or truncation will then occur in these columns as required
# (depending on how they were configured).
# Note that regardless of the value passed to max_table_width, the table will always be left wide
# enough to accommodate at least 1 character's width of content, 1 character of left padding and
# 1 character of right padding in each column, together with border characters (1 on each side
# of the table and 1 between adjacent columns). I.e. there is a certain width below width the
# Table will refuse to shrink itself.
# @return [Table] the Table itself
def pack(max_table_width: :auto)
get_columns.each { |column| column.width = Util.wrapped_width(column.header) }
@sources.each_with_index do |source, row_index|
get_columns.each_with_index do |column, column_index|
cell = column.body_cell(source, row_index: row_index, column_index: column_index)
cell_width = Util.wrapped_width(cell.formatted_content)
column.width = Util.max(column.width, cell_width)
end
end
shrink_to(max_table_width == :auto ? TTY::Screen.width : max_table_width) if max_table_width
if @title
border_edge_width = (@border == :blank ? 0 : 2)
columns = get_columns
expand_to(
Unicode::DisplayWidth.of(@title) +
columns.first.left_padding +
columns.last.right_padding +
border_edge_width
)
end
self
end
# Creates a new {Table} from the current Table, transposed, that is rotated 90 degrees,
# relative to the current Table, so that the header names of the current Table form the
# content of left-most column of the new Table, and each column thereafter corresponds to one of the
# elements of the current Table's sources, with the header of that column being the String
# value of that element.
#
# @example
# puts Tabulo::Table.new(-1..1, :even?, :odd?, :abs).transpose
# # => +-------+--------------+--------------+--------------+
# # | | -1 | 0 | 1 |
# # +-------+--------------+--------------+--------------+
# # | even? | false | true | false |
# # | odd? | true | false | true |
# # | abs | 1 | 0 | 1 |
#
# @param [Hash] opts Options for configuring the new, transposed {Table}.
# The following options are the same as the keyword params for the {#initialize} method for
# {Table}: column_width, column_padding, formatter,
# header_frequency, row_divider_frequency, wrap_header_cells_to,
# wrap_body_cells_to, border, border_styler, title,
# title_styler, truncation_indicator, align_header, align_body,
# align_title.
# These are applied in the same way as documented for {#initialize}, when
# creating the new, transposed Table. Any options not specified explicitly in the call to {#transpose}
# will inherit their values from the original {Table} (with the exception of settings
# for the left-most column, containing the field names, which are determined as described
# below). In addition, the following options also apply to {#transpose}:
# @option opts [nil, Integer] :field_names_width Determines the width of the left-most column of the
# new Table, which contains the names of "fields" (corresponding to the original Table's
# column headings). If this is not provided, then by default this column will be made just
# wide enough to accommodate its contents.
# @option opts [String] :field_names_header By default the left-most column will have a
# blank header; but this can be overridden by passing a String to this option.
# @option opts [:left, :center, :right] :field_names_header_alignment Specifies how the
# header text of the left-most column (if it has header text) should be aligned.
# @option opts [:left, :center, :right] :field_names_body_alignment Specifies how the
# body text of the left-most column should be aligned.
# @option opts [#to_proc] :headers A lambda or other callable object that
# will be passed in turn each of the elements of the current Table's sources
# Enumerable, to determine the text to be displayed in the header of each column of the
# new Table (other than the left-most column's header, which is determined as described
# above).
# @return [Table] a new {Table}
# @raise [InvalidBorderError] if invalid argument passed to `border` parameter.
def transpose(opts = {})
default_opts = [:align_body, :align_header, :align_title, :border, :border_styler, :column_padding,
:column_width, :formatter, :header_frequency, :row_divider_frequency, :title, :title_styler,
:truncation_indicator, :wrap_body_cells_to, :wrap_header_cells_to].map do |sym|
[sym, instance_variable_get("@#{sym}")]
end.to_h
initializer_opts = default_opts.merge(Util.slice_hash(opts, *default_opts.keys))
default_extra_opts = { field_names_body_alignment: :right, field_names_header: "",
field_names_header_alignment: :right, field_names_width: nil, headers: :to_s.to_proc }
extra_opts = default_extra_opts.merge(Util.slice_hash(opts, *default_extra_opts.keys))
# The underlying enumerable for the new table, is the columns of the original table.
fields = column_registry.values
Table.new(fields, **initializer_opts) do |t|
# Left hand column of new table, containing field names
width_opt = extra_opts[:field_names_width]
field_names_width = (width_opt.nil? ? fields.map { |f| f.header.length }.max : width_opt)
t.add_column(:dummy, align_body: extra_opts[:field_names_body_alignment],
align_header: extra_opts[:field_names_header_alignment], header: extra_opts[:field_names_header],
width: field_names_width, &:header)
# Add a column to the new table for each of the original table's sources
sources.each_with_index do |source, i|
t.add_column(i, header: extra_opts[:headers].call(source)) do |original_column|
original_column.body_cell_value(source, row_index: i, column_index: original_column.index)
end
end
end
end
# @!visibility private
def formatted_body_row(source, header:, divider:, index:)
cells = get_columns.map.with_index { |c, i| c.body_cell(source, row_index: index, column_index: i) }
inner = format_row(cells, @wrap_body_cells_to)
if @title && header == :top
Util.condense_lines([horizontal_rule(:title_top), formatted_title, horizontal_rule(:title_bottom),
formatted_header, horizontal_rule(:middle), inner])
elsif header == :top
Util.condense_lines([horizontal_rule(:top), formatted_header, horizontal_rule(:middle), inner])
elsif header
Util.condense_lines([horizontal_rule(:middle), formatted_header, horizontal_rule(:middle), inner])
elsif divider
Util.condense_lines([horizontal_rule(:middle), inner])
else
inner
end
end
private
# @!visibility private
def get_columns
column_registry.values
end
# @!visibility private
def add_column_before(column, label, before)
old_column_entries = @column_registry.to_a
new_column_entries = []
old_column_entries.each do |entry|
new_column_entries << [label, column] if entry[0] == before
new_column_entries << entry
end
found = (new_column_entries.size == old_column_entries.size + 1)
raise InvalidColumnLabelError, "There is no column with label #{before}" unless found
@column_registry = new_column_entries.to_h
end
# @!visibility private
def add_column_final(column, label)
@column_registry[label] = column
end
# @visibility private
def formatted_title
columns = get_columns
extra_for_internal_dividers = (@border == :blank ? 0 : 1)
title_cell_width = columns.inject(0) do |total_width, column|
total_width + column.padded_width + extra_for_internal_dividers
end
title_cell_width -= (columns.first.left_padding + columns.last.right_padding + extra_for_internal_dividers)
styler =
if @title_styler
case @title_styler.arity
when 1
-> (_val, str) { @title_styler.call(str) }
when 2
-> (_val, str, _cell_data, line_index) { @title_styler.call(str, line_index) }
end
else
-> (_val, str) { str }
end
title_cell = Cell.new(
alignment: @align_title,
cell_data: nil,
formatter: -> (s) { s },
left_padding: columns.first.left_padding,
padding_character: PADDING_CHARACTER,
right_padding: columns.last.right_padding,
styler: styler,
truncation_indicator: @truncation_indicator,
value: @title,
width: title_cell_width,
wrap_preserve: @wrap_preserve,
)
cells = [title_cell]
max_cell_height = cells.map(&:height).max
row_height = ([nil, max_cell_height].compact.min || 1)
subcell_stacks = cells.map do |cell|
cell.padded_truncated_subcells(row_height)
end
subrows = subcell_stacks.transpose.map do |subrow_components|
@border_instance.join_cell_contents(subrow_components)
end
Util.join_lines(subrows)
end
# @!visibility private
def normalize_column_label(label)
case label
when Integer, Symbol
label
when String
label.to_sym
end
end
# @!visibility private
def expand_to(min_table_width)
columns = get_columns
num_columns = columns.count
total_columns_padded_width = columns.inject(0) { |sum, column| sum + column.padded_width }
total_borders = num_columns + 1
unadjusted_table_width = total_columns_padded_width + total_borders
required_increase = Util.max(min_table_width - unadjusted_table_width, 0)
required_increase.times do
narrowest_column = columns.inject(columns.first) do |narrowest, column|
column.width <= narrowest.width ? column : narrowest
end
narrowest_column.width += 1
end
end
# @!visibility private
def shrink_to(max_table_width)
columns = get_columns
num_columns = columns.count
total_columns_padded_width = columns.inject(0) { |sum, column| sum + column.padded_width }
total_padding = columns.inject(0) { |sum, column| sum + column.total_padding }
total_borders = num_columns + 1
unadjusted_table_width = total_columns_padded_width + total_borders
# Ensure max table width is at least wide enough to accommodate table borders and padding
# and one character of content.
min_table_width = total_padding + total_borders + column_registry.count
max_table_width = Util.max(min_table_width, max_table_width)
required_reduction = Util.max(unadjusted_table_width - max_table_width, 0)
required_reduction.times do
widest_column = columns.inject(columns.first) do |widest, column|
column.width >= widest.width ? column : widest
end
widest_column.width -= 1
end
end
# @!visibility private
#
# Formats a single header row or body row as a String.
#
# @param [String[][]] cells an Array of Array-of-Strings, each of which represents a
# "stack" of "subcells". Each such stack represents the wrapped content of a given
# "cell" in this row, from the top down, one String for each "line".
# Each String includes the spaces, if any, on either side required for the
# "internal padding" of the cell to carry out the cell content alignment -- but
# does not include the single character of padding around each column.
# @param [Integer] wrap_cells_to the number of "lines" of wrapped content to allow
# before truncating.
# @return [String] the entire formatted row including all padding and borders.
def format_row(cells, wrap_cells_to)
max_cell_height = cells.map(&:height).max
row_height = ([wrap_cells_to, max_cell_height].compact.min || 1)
subcell_stacks = cells.map do |cell|
cell.padded_truncated_subcells(row_height)
end
subrows = subcell_stacks.transpose.map do |subrow_components|
@border_instance.join_cell_contents(subrow_components)
end
Util.join_lines(subrows)
end
# @!visibility private
def validate_character(character, default, exception_class, message_fragment)
case (c = (character || default))
when nil
; # do nothing
when String
if Unicode::DisplayWidth.of(c) != 1
raise exception_class, "#{message_fragment} is neither nil nor a single-character String"
end
else
raise exception_class, "#{message_fragment} is neither nil nor a single-character String"
end
c
end
end
end