pagy.rb in pagy-4.2.0

- old
+ new
@@ -1,49 +1,67 @@
 # See Pagy API documentation: https://ddnexus.github.io/pagy/api/pagy
-# encoding: utf-8
 # frozen_string_literal: true
 
 require 'pathname'
 
-class Pagy ; VERSION = '4.1.0'
+# main class
+class Pagy
+  VERSION = '4.2.0'
 
   # Root pathname to get the path of Pagy files like templates or dictionaries
-  def self.root = @root ||= Pathname.new(__FILE__).dirname.freeze
+  def self.root
+    @root ||= Pathname.new(__dir__).freeze
+  end
 
   # default vars
-  VARS = { page:1, items:20, outset:0, size:[1,4,4,1], page_param: :page, params:{}, anchor:'', link_extra:'', i18n_key:'pagy.item_name', cycle:false }
+  VARS = { page: 1, items: 20, outset: 0, size: [1, 4, 4, 1], page_param: :page,              # rubocop:disable Style/MutableConstant
+           params: {}, anchor: '', link_extra: '', i18n_key: 'pagy.item_name', cycle: false }
 
   attr_reader :count, :page, :items, :vars, :pages, :last, :offset, :from, :to, :prev, :next
 
+  INSTANCE_VARS_MIN = { count: 0, items: 1, page: 1, outset: 0 }.freeze
+
   # Merge and validate the options, do some simple arithmetic and set the instance variables
   def initialize(vars)
-    @vars = VARS.merge(vars.delete_if{|_,v| v.nil? || v == '' })               # default vars + cleaned vars
-    { count:0, items:1, outset:0, page:1 }.each do |k,min|                     # validate instance variables
-      (@vars[k] && instance_variable_set(:"@#{k}", @vars[k].to_i) >= min) \
-         or raise(VariableError.new(self), "expected :#{k} >= #{min}; got #{@vars[k].inspect}")
+    @vars = VARS.merge( vars.delete_if{|_,v| v.nil? || v == '' } )
+
+    INSTANCE_VARS_MIN.each do |name,min|
+      raise VariableError.new(self), "expected :#{name} >= #{min}; got #{@vars[name].inspect}" \
+            unless @vars[name] && instance_variable_set(:"@#{name}", @vars[name].to_i) >= min
     end
-    @pages = @last = [(@count.to_f / @items).ceil, 1].max                      # cardinal and ordinal meanings
-    @page <= @last or raise(OverflowError.new(self), "expected :page in 1..#{@last}; got #{@page.inspect}")
-    @offset = @items * (@page - 1) + @outset                                   # pagination offset + outset (initial offset)
-    @items  = @count - ((@pages-1) * @items) if @page == @last && @count > 0   # adjust items for last non-empty page
-    @from   = @count == 0 ? 0 : @offset+1 - @outset                            # page begins from item
-    @to     = @count == 0 ? 0 : @offset + @items - @outset                     # page ends to item
-    @prev   = (@page-1 unless @page == 1)                                      # nil if no prev page
-    @next   = @page == @last ? (1 if @vars[:cycle]) : @page+1                  # nil if no next page, 1 if :cycle
+    @pages = @last = [(@count.to_f / @items).ceil, 1].max
+    raise OverflowError.new(self), "expected :page in 1..#{@last}; got #{@page.inspect}" if @page > @last
+
+    @offset = @items * (@page - 1) + @outset
+    @items  = @count - ((@pages-1) * @items) if @page == @last && @count.positive?
+    @from   = @count.zero? ? 0 : @offset + 1 - @outset
+    @to     = @count.zero? ? 0 : @offset + @items - @outset
+    @prev   = (@page-1 unless @page == 1)
+    @next   = @page == @last ? (1 if @vars[:cycle]) : @page + 1
   end
 
   # Return the array of page numbers and :gap items e.g. [1, :gap, 7, 8, "9", 10, 11, :gap, 36]
   def series(size=@vars[:size])
-    (series = []) and size.empty? and return series
-    4.times{|i| (size[i]>=0 rescue nil) or raise(VariableError.new(self), "expected 4 items >= 0 in :size; got #{size.inspect}")}
-    [*0..size[0], *@page-size[1]..@page+size[2], *@last-size[3]+1..@last+1].sort!.each_cons(2) do |a, b|
-      if    a<0 || a==b || a>@last; next                                  # skip out of range and duplicates
-      elsif a+1 == b; series.push(a)                                      # no gap     -> no additions
-      elsif a+2 == b; series.push(a, a+1)                                 # 1 page gap -> fill with missing page
-      else            series.push(a, :gap)                                # n page gap -> add gap
-      end                                                                 # skip the end boundary (last+1)
-    end                                                                   # shift the start boundary (0) and
-    series.shift; series[series.index(@page)] = @page.to_s; series        # convert the current page to String
+    return [] if size.empty?
+    raise VariableError.new(self), "expected 4 items >= 0 in :size; got #{size.inspect}" \
+          unless size.size == 4 && size.all?{ |num| num >= 0 rescue false }  # rubocop:disable Style/RescueModifier
+
+    series = []
+    [ *0..size[0],                                   # initial pages from 0
+      *@page-size[1]..@page+size[2],                 # around current page
+      *@last-size[3]+1..@last+1                      # final pages till @last+1
+    ].sort!.each_cons(2) do |left, right|            # sort and loop by 2
+      next if left.negative? || left == right        # skip out of range and duplicates
+      break if left > @last                          # break if out of @last boundary
+      case right
+      when left+1 then series.push(left)             # no gap     -> no additions
+      when left+2 then series.push(left, left+1)     # 1 page gap -> fill with missing page
+      else             series.push(left, :gap)       # n page gap -> add gap
+      end
+    end
+    series.shift                                     # shift the start boundary (0)
+    series[series.index(@page)] = @page.to_s         # convert the current page to String
+    series
   end
 
 end
 
 require 'pagy/backend'