Module: Lazier::TimeZone::ClassMethods

Defined in:

lib/lazier/datetime.rb

Overview

General methods.

Instance Method Summary

• #compare(left, right) ⇒ Fixnum

  Compares two timezones.

• #find(name, dst_label = nil) ⇒ TimeZone

  Find a zone by its name.

• #format_offset(offset, colon = true) ⇒ String

  Returns a +HH:MM formatted representation of the offset.

• #list_all(with_dst = true, dst_label = nil) ⇒ Array

  Returns a list of names of all timezones.

• #parameterize_zone(tz, with_offset = true) ⇒ String

  Returns a string representation of a timezone.

• #rationalize_offset(offset) ⇒ Rational

  Returns an offset in rational value.

• #unparameterize_zone(tz, as_string = false, dst_label = nil) ⇒ String|TimeZone

  Finds a parameterized timezone.

Instance Method Details

#compare(left, right) ⇒ Fixnum

Compares two timezones. They are sorted by the location name.

Parameters:

• left (String|TimeZone) —

  The first zone name to compare.

• right (String|TimeZone) —

  The second zone name to compare.

Returns:

• (Fixnum) —

  The result of comparison, like Ruby's operator <=>.

# File 'lib/lazier/datetime.rb', line 373

def compare(left, right)
  left = left.to_str if left.is_a?(::ActiveSupport::TimeZone)
  right = right.to_str if right.is_a?(::ActiveSupport::TimeZone)
  left.ensure_string.split(" ", 2)[1] <=> right.ensure_string.split(" ", 2)[1]
end

#find(name, dst_label = nil) ⇒ TimeZone

Find a zone by its name.

Parameters:

• name (String) —

  The zone name.

• dst_label (String) (defaults to: nil) —

  Label for the DST indication. Defaults to (DST).

Returns:

• (TimeZone) —

  A timezone or nil if no zone was found.

# File 'lib/lazier/datetime.rb', line 299

def find(name, dst_label = nil)
  catch(:zone) do
    ::ActiveSupport::TimeZone.all.each do |zone|
      zone.aliases.each do |zone_alias|
        throw(:zone, zone) if [zone.to_str(zone_alias), zone.to_str_with_dst(dst_label, nil, zone_alias)].include?(name)
      end
    end

    nil
  end
end

#format_offset(offset, colon = true) ⇒ String

Returns a +HH:MM formatted representation of the offset.

Parameters:

• offset (Rational|Fixnum) —

  The offset to represent, in seconds or as a rational.

• colon (Boolean) (defaults to: true) —

  If to put the colon in the output string.

Returns:

• (String) —

  The formatted offset.

# File 'lib/lazier/datetime.rb', line 290

def format_offset(offset, colon = true)
  self.seconds_to_utc_offset(offset.is_a?(::Rational) ? (offset * 86400).to_i : offset, colon)
end

#list_all(with_dst = true, dst_label = nil) ⇒ Array

Returns a list of names of all timezones.

Parameters:

• with_dst (Boolean) (defaults to: true) —

  If include DST version of the zones.

• dst_label (String) (defaults to: nil) —

  Label for the DST indication. Defaults to (DST).

Returns:

• (Array) —

  A list of names of timezones.

# File 'lib/lazier/datetime.rb', line 316

def list_all(with_dst = true, dst_label = nil)
  dst_label ||= "(DST)"

  @zones_names ||= { "STANDARD" => ::ActiveSupport::TimeZone.all.collect(&:to_s) }
  @zones_names["DST[#{dst_label}]-STANDARD"] ||= ::ActiveSupport::TimeZone.all.collect { |zone| fetch_aliases(zone, dst_label) }.flatten.compact.uniq.sort { |a,b| ::ActiveSupport::TimeZone.compare(a, b) } # Sort by name

  @zones_names["#{with_dst ? "DST[#{dst_label}]-" : ""}STANDARD"]
end

#parameterize_zone(tz, with_offset = true) ⇒ String

Returns a string representation of a timezone.

DateTime.parameterize_zone(ActiveSupport::TimeZone["Pacific Time (US & Canada)"])
# => "-0800@pacific-time-us-canada"

Parameters:

• tz (TimeZone) —

  The zone to represent.

• with_offset (Boolean) (defaults to: true) —

  If to include offset into the representation.

Returns:

• (String) —

  A string representation which can be used for searches.

# File 'lib/lazier/datetime.rb', line 334

def parameterize_zone(tz, with_offset = true)
  tz = tz.to_s if !tz.is_a?(::String)

  if tz =~ /^(\([a-z]+([+-])(\d{2})(:?)(\d{2})\)\s(.+))$/i then
    with_offset ? "#{$2}#{$3}#{$5}@#{$6.parameterize}" : $6.parameterize
  elsif !with_offset then
    tz.gsub(/^([+-]?(\d{2})(:?)(\d{2})@)/, "")
  else
    tz.parameterize
  end
end

#rationalize_offset(offset) ⇒ Rational

Returns an offset in rational value.

Parameters:

• offset (Fixnum) —

  The offset to convert.

Returns:

• (Rational) —

  The converted offset.

# File 'lib/lazier/datetime.rb', line 281

def rationalize_offset(offset)
  ::TZInfo::OffsetRationals.rational_for_offset(offset.is_a?(::Fixnum) ? offset : offset.offset)
end

#unparameterize_zone(tz, as_string = false, dst_label = nil) ⇒ String|TimeZone

Finds a parameterized timezone.

Parameters:

• tz (String) —

  The zone to unparameterize.

• as_string (Boolean) (defaults to: false) —

  If return just the zone name.

• dst_label (String) (defaults to: nil) —

  Label for the DST indication. Defaults to (DST).

Returns:

• (String|TimeZone) —

  The found timezone or nil if the zone is not valid.

See Also:

• DateTime#parameterize_zone

# File 'lib/lazier/datetime.rb', line 353

def unparameterize_zone(tz, as_string = false, dst_label = nil)
  tz = parameterize_zone(tz, false)
  matcher = /(#{Regexp.quote(tz)})$/

  rv = catch(:zone) do
    list_all(true, dst_label).each do |zone|
      throw(:zone, zone) if parameterize_zone(zone, false) =~ matcher
    end

    nil
  end

  rv ? (as_string ? rv : self.find(rv, dst_label)) : nil
end