Add Sorbet plugin for delegate.

Library/Homebrew/sorbet/plugins/delegate.rb

@@ -0,0 +1,21 @@
+# typed: strict
+# frozen_string_literal: true
+
+source = ARGV[5]
+
+methods = if (single = source[/delegate\s+([^:]+):\s+/, 1])
+  [single]
+else
+  multiple = source[/delegate\s+\[(.*?)\]\s+=>\s+/m, 1]
+  non_comments = multiple.gsub(/\#.*$/, "")
+  non_comments.scan(/:([^:,\s]+)/).flatten
+end
+
+methods.each do |method|
+  puts <<~RUBY
+    # typed: strict
+
+    sig {params(arg0: T.untyped).returns(T.untyped)}
+    def #{method}(*arg0); end
+  RUBY
+end

Library/Homebrew/sorbet/triggers.yml

@@ -4,3 +4,4 @@ ruby_extra_args:
 triggers:
   using: sorbet/plugins/unpack_strategy_magic.rb
   attr_predicate: sorbet/plugins/attr_predicate.rb
+  delegate: sorbet/plugins/delegate.rb