module Strings::Truncate
A module responsible for text truncation
Constants
- DEFAULT_LENGTH
- DEFAULT_TRAILING
Public Class Methods
display_width(string)
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Visible width of a string
@api private
# File lib/strings/truncate.rb, line 101 def display_width(string) Unicode::DisplayWidth.of(Strings::ANSI.sanitize(string)) end
shorten(original_chars, chars, length_without_trailing)
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Perform actual shortening of the text
@return [String]
@api private
# File lib/strings/truncate.rb, line 71 def shorten(original_chars, chars, length_without_trailing) truncated = [] char_width = display_width(chars[0]) while length_without_trailing - char_width > 0 orig_char = original_chars.shift char = chars.shift break unless char while orig_char != char # consume ansi ansi = true truncated << orig_char orig_char = original_chars.shift end truncated << char char_width = display_width(char) length_without_trailing -= char_width end truncated << ["\e[0m"] if ansi truncated end
to_chars(text)
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@api private
# File lib/strings/truncate.rb, line 93 def to_chars(text) UnicodeUtils.each_grapheme(text) end
truncate(text, truncate_at = DEFAULT_LENGTH, options = {})
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Truncate
a text at a given length (defualts to 30)
@param [String] text
the text to be truncated
@param [Integer] truncate_at
the width at which to truncate the text
@param [Hash] options
@option options [Symbol] :separator the character for splitting words @option options [Symbol] :trailing the character for ending sentence
@example
text = "The sovereignest thing on earth is parmacetti for an inward bruise." Strings::Truncate.truncate(text) # => "The sovereignest thing on ear…" Strings::Truncate.truncate(text, 20) # => "The sovereignest th…" Strings::Truncate.truncate(text, 20, separator: ' ' ) # => "The sovereignest…" Strings::Truncate.truncate(40, trailing: '... (see more)' ) # => "The sovereignest thing on... (see more)"
@api public
# File lib/strings/truncate.rb, line 42 def truncate(text, truncate_at = DEFAULT_LENGTH, options = {}) if truncate_at.is_a?(Hash) options = truncate_at truncate_at = DEFAULT_LENGTH end if display_width(text) <= truncate_at.to_i || truncate_at.to_i.zero? return text.dup end trail = options.fetch(:trailing) { DEFAULT_TRAILING } separation = options.fetch(:separator) { nil } sanitized_text = Strings::ANSI.sanitize(text) length_without_trailing = truncate_at - display_width(trail) chars = to_chars(sanitized_text).to_a stop = chars[0, length_without_trailing].rindex(separation) slice_length = stop || length_without_trailing sliced_chars = chars[0, slice_length] original_chars = to_chars(text).to_a[0, 3 * slice_length] shorten(original_chars, sliced_chars, length_without_trailing).join + trail end
Private Instance Methods
display_width(string)
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Visible width of a string
@api private
# File lib/strings/truncate.rb, line 101 def display_width(string) Unicode::DisplayWidth.of(Strings::ANSI.sanitize(string)) end
shorten(original_chars, chars, length_without_trailing)
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Perform actual shortening of the text
@return [String]
@api private
# File lib/strings/truncate.rb, line 71 def shorten(original_chars, chars, length_without_trailing) truncated = [] char_width = display_width(chars[0]) while length_without_trailing - char_width > 0 orig_char = original_chars.shift char = chars.shift break unless char while orig_char != char # consume ansi ansi = true truncated << orig_char orig_char = original_chars.shift end truncated << char char_width = display_width(char) length_without_trailing -= char_width end truncated << ["\e[0m"] if ansi truncated end
to_chars(text)
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@api private
# File lib/strings/truncate.rb, line 93 def to_chars(text) UnicodeUtils.each_grapheme(text) end
truncate(text, truncate_at = DEFAULT_LENGTH, options = {})
click to toggle source
Truncate
a text at a given length (defualts to 30)
@param [String] text
the text to be truncated
@param [Integer] truncate_at
the width at which to truncate the text
@param [Hash] options
@option options [Symbol] :separator the character for splitting words @option options [Symbol] :trailing the character for ending sentence
@example
text = "The sovereignest thing on earth is parmacetti for an inward bruise." Strings::Truncate.truncate(text) # => "The sovereignest thing on ear…" Strings::Truncate.truncate(text, 20) # => "The sovereignest th…" Strings::Truncate.truncate(text, 20, separator: ' ' ) # => "The sovereignest…" Strings::Truncate.truncate(40, trailing: '... (see more)' ) # => "The sovereignest thing on... (see more)"
@api public
# File lib/strings/truncate.rb, line 42 def truncate(text, truncate_at = DEFAULT_LENGTH, options = {}) if truncate_at.is_a?(Hash) options = truncate_at truncate_at = DEFAULT_LENGTH end if display_width(text) <= truncate_at.to_i || truncate_at.to_i.zero? return text.dup end trail = options.fetch(:trailing) { DEFAULT_TRAILING } separation = options.fetch(:separator) { nil } sanitized_text = Strings::ANSI.sanitize(text) length_without_trailing = truncate_at - display_width(trail) chars = to_chars(sanitized_text).to_a stop = chars[0, length_without_trailing].rindex(separation) slice_length = stop || length_without_trailing sliced_chars = chars[0, slice_length] original_chars = to_chars(text).to_a[0, 3 * slice_length] shorten(original_chars, sliced_chars, length_without_trailing).join + trail end