Set theme for stats in plugin base class

Simplifies writing a plugin, so that a theme doesn't need to be passed
when initializing each `Stat`.

lib/repofetch.rb

@@ -190,16 +190,28 @@ def stats
       []
     end
 
+    # Adds +theme+ to the stats, mutating those stats.
+    #
+    # @return [Array<Stat>]
+    def theme_stats!
+      stats.each do |stat|
+        stat.theme = theme if stat.respond_to?(:theme=)
+      end
+    end
+
     # Makes an array of stat lines, including the header and separator.
-    def stat_lines
-      [header, separator, *stats.map(&:to_s)]
+    #
+    # Mutates +stats+ to add the +theme+.
+    def stat_lines!
+      [header, separator, *theme_stats!.map(&:to_s)]
     end
 
     # Zips ASCII lines with stat lines.
     #
     # If there are more of one than the other, than the zip will be padded with empty strings.
     def zipped_lines
       ascii_lines = ascii.lines.map(&:chomp)
+      stat_lines = stat_lines!
       if ascii_lines.length > stat_lines.length
         ascii_lines.zip(stat_lines)
       else
@@ -211,17 +223,17 @@ def zipped_lines
   # Base class for stats.
   class Stat
     attr_reader :label, :value, :emoji
+    attr_writer :theme
 
     # Creates a stat
     #
     # @param [String] label The label of the stat
     # @param value The value of the stat
     # @param [String] emoji An optional emoji for the stat
-    def initialize(label, value, emoji: nil, theme: nil)
+    def initialize(label, value, emoji: nil)
       @label = label
       @value = value
       @emoji = emoji
-      @theme = theme
       @label_styles = []
     end
 

lib/repofetch/github.rb

@@ -106,27 +106,27 @@ def repo_stats
     end
 
     def url
-      Repofetch::Stat.new('URL', repo_stats['clone_url'], emoji: '🌐', theme: theme)
+      Repofetch::Stat.new('URL', repo_stats['clone_url'], emoji: '🌐')
     end
 
     def stargazers
-      Repofetch::Stat.new('stargazers', repo_stats['stargazers_count'], emoji: '⭐', theme: theme)
+      Repofetch::Stat.new('stargazers', repo_stats['stargazers_count'], emoji: '⭐')
     end
 
     def subscribers
-      Repofetch::Stat.new('subscribers', repo_stats['subscribers_count'], emoji: '👀', theme: theme)
+      Repofetch::Stat.new('subscribers', repo_stats['subscribers_count'], emoji: '👀')
     end
 
     def forks
-      Repofetch::Stat.new('forks', repo_stats['forks_count'], emoji: '🔱', theme: theme)
+      Repofetch::Stat.new('forks', repo_stats['forks_count'], emoji: '🔱')
     end
 
     def created
-      Repofetch::TimespanStat.new('created', repo_stats['created_at'], emoji: '🐣', theme: theme)
+      Repofetch::TimespanStat.new('created', repo_stats['created_at'], emoji: '🐣')
     end
 
     def updated
-      Repofetch::TimespanStat.new('updated', repo_stats['updated_at'], emoji: '📤', theme: theme)
+      Repofetch::TimespanStat.new('updated', repo_stats['updated_at'], emoji: '📤')
     end
 
     def size
@@ -136,17 +136,17 @@ def size
         significant: false,
         strip_insignificant_zeros: false
       )
-      Repofetch::Stat.new('size', byte_size, emoji: '💽', theme: theme)
+      Repofetch::Stat.new('size', byte_size, emoji: '💽')
     end
 
     def issues
       @issue_search = @client.search_issues("repo:#{repo_id} is:issue", per_page: 1, page: 0) if @issue_search.nil?
-      Repofetch::Stat.new('issues', @issue_search['total_count'], emoji: '❗', theme: theme)
+      Repofetch::Stat.new('issues', @issue_search['total_count'], emoji: '❗')
     end
 
     def pull_requests
       @pr_search = @client.search_issues("repo:#{repo_id} is:pr", per_page: 1, page: 0) if @pr_search.nil?
-      Repofetch::Stat.new('pull requests', @pr_search['total_count'], emoji: '🔀', theme: theme)
+      Repofetch::Stat.new('pull requests', @pr_search['total_count'], emoji: '🔀')
     end
   end
 end