Deprecate use of == and != for Redis::Future

Author: GustavoCaso

lib/redis.rb

@@ -5,6 +5,10 @@
 
 class Redis
 
+  def self.deprecate(message, trace = caller[0])
+    $stderr.puts "\n#{message} (in #{trace})"
+  end
+
   def self.current
     @current ||= Redis.new
   end

lib/redis/pipeline.rb

@@ -132,16 +132,20 @@ class Future < BasicObject
 
     attr_reader :timeout
 
-    # Avoid allowing people to use == inside a pipelined
-    undef :==
-
     def initialize(command, transformation, timeout)
       @command = command
       @transformation = transformation
       @timeout = timeout
       @object = FutureNotReady
     end
 
+    def ==(*)
+      message = "The method == and != is deprecated for Redis::Future and will be removed in 4.2.0"
+      message << " - You probably meant to call .value == or .value !="
+      ::Redis.deprecate(message)
+      super
+    end
+
     def inspect
       "<Redis::Future #{@command.inspect}>"
     end

test/pipelining_commands_test.rb

@@ -126,14 +126,6 @@ def test_futures_raise_when_trying_to_access_their_values_too_early
     end
   end
 
-  def test_futures_raise_when_trying_to_compare_their_value_too_early
-    r.pipelined do
-      assert_raises(NoMethodError) do
-        r.sadd("foo", 1) == 1
-      end
-    end
-  end
-
   def test_futures_raise_when_command_errors_and_needs_transformation
     assert_raises(Redis::CommandError) do
       r.pipelined do