Support min_named :formula_or_cask.

Library/Homebrew/cli/parser.rb

@@ -455,11 +455,13 @@ module Homebrew
       def check_named_args(args)
         min_exception = case @min_named_type
         when :cask
-          Cask::CaskUnspecifiedError.new
+          Cask::CaskUnspecifiedError
         when :formula
-          FormulaUnspecifiedError.new
+          FormulaUnspecifiedError
+        when :formula_or_cask
+          FormulaOrCaskUnspecifiedError
         when :keg
-          KegUnspecifiedError.new
+          KegUnspecifiedError
         else
           MinNamedArgumentsError.new(@min_named_args)
         end

Library/Homebrew/cmd/install.rb

@@ -143,7 +143,7 @@ module Homebrew
       end
       cask_options
 
-      min_named 1
+      min_named :formula_or_cask
     end
   end
 

Library/Homebrew/cmd/reinstall.rb

@@ -80,7 +80,7 @@ module Homebrew
       end
       cask_options
 
-      min_named 1
+      min_named :formula_or_cask
     end
   end
 

Library/Homebrew/exceptions.rb

@@ -27,6 +27,13 @@ class FormulaUnspecifiedError < UsageError
   end
 end
 
+# Raised when a command expects a formula or cask and none was specified.
+class FormulaOrCaskUnspecifiedError < UsageError
+  def initialize
+    super "this command requires a formula or cask argument"
+  end
+end
+
 # Raised when a command expects a keg and none was specified.
 class KegUnspecifiedError < UsageError
   def initialize