2 files changed, 18 insertions, 1 deletions
diff --git a/activesupport/lib/active_support/deprecation/behaviors.rb b/activesupport/lib/active_support/deprecation/behaviors.rb
index 9f9dca8453..0cdc7e96f7 100644
--- a/activesupport/lib/active_support/deprecation/behaviors.rb
+++ b/activesupport/lib/active_support/deprecation/behaviors.rb
@@ -38,6 +38,18 @@ module ActiveSupport
       silence: ->(message, callstack) {},
     }
 
+    # Behavior module allows to determine how to display deprecation messages.
+    # You can set any behaviors from +DEFAULT_BEHAVIORS+ constant or create
+    # custom behavior. Available behaviors:
+    #
+    # [+raise+]   Raise <tt>ActiveSupport::DeprecationException</tt>.
+    # [+stderr+]  Log all deprecation warnings to +$stderr+.
+    # [+log+]     Log all deprecation warnings to +Rails.logger+.
+    # [+notify+]  Use +ActiveSupport::Notifications+ to notify +deprecation.rails+.
+    # [+silence+] Do nothing.
+    #
+    # Setting behaviors only affects deprecations that happen after boot time.
+    # For more information you can read documentation for +behavior=+ method.
     module Behavior
       # Whether to print a backtrace along with the warning.
       attr_accessor :debug
diff --git a/activesupport/lib/active_support/deprecation/proxy_wrappers.rb b/activesupport/lib/active_support/deprecation/proxy_wrappers.rb
index dfdb8034e5..c6d2b5e795 100644
--- a/activesupport/lib/active_support/deprecation/proxy_wrappers.rb
+++ b/activesupport/lib/active_support/deprecation/proxy_wrappers.rb
@@ -104,7 +104,7 @@ module ActiveSupport
     end
 
     # DeprecatedConstantProxy transforms a constant into a deprecated one. It
-    # takes the names of an old (deprecated) constant and of a new contstant
+    # takes the names of an old (deprecated) constant and of a new constant
     # (both in string form) and optionally a deprecator. The deprecator defaults
     # to +ActiveSupport::Deprecator+ if none is specified. The deprecated constant
     # now returns the value of the new one.
@@ -127,6 +127,11 @@ module ActiveSupport
         @deprecator = deprecator
       end
 
+      # Returns class of a new constant.
+      #
+      #   PLANETS_POST_2006 = %w(mercury venus earth mars jupiter saturn uranus neptune)
+      #   PLANETS = ActiveSupport::Deprecation::DeprecatedConstantProxy.new('PLANETS', 'PLANETS_POST_2006')
+      #   PLANETS.class # => Array
       def class
         target.class
       end