Friendlier runtime exception if delegatee is nil

2 files changed, 10 insertions, 4 deletions

diff --git a/activesupport/lib/active_support/core_ext/module/delegation.rb b/activesupport/lib/active_support/core_ext/module/delegation.rb
index cea3fb7f57..11e01437aa 100644
--- a/activesupport/lib/active_support/core_ext/module/delegation.rb
+++ b/activesupport/lib/active_support/core_ext/module/delegation.rb
@@ -108,15 +108,21 @@ class Module
 
     prefix = options[:prefix] && "#{options[:prefix] == true ? to : options[:prefix]}_"
 
-    allow_nil = options[:allow_nil] && "#{to} && "
-
     file, line = caller.first.split(':', 2)
     line = line.to_i
 
     methods.each do |method|
+      on_nil =
+        if options[:allow_nil]
+          'return'
+        else
+          %(raise "#{self}##{prefix}#{method} delegated to #{to}.#{method}, but #{to} is nil: \#{self.inspect}")
+        end
+
       module_eval(<<-EOS, file, line)
         def #{prefix}#{method}(*args, &block)                           # def customer_name(*args, &block)
-          #{allow_nil}#{to}.__send__(#{method.inspect}, *args, &block)  #   client && client.__send__(:name, *args, &block)
+          #{on_nil} if #{to}.nil?
+          #{to}.__send__(#{method.inspect}, *args, &block)  #   client && client.__send__(:name, *args, &block)
         end                                                             # end
       EOS
     end
diff --git a/activesupport/test/core_ext/module_test.rb b/activesupport/test/core_ext/module_test.rb
index c3c696f93a..f8387ae4ab 100644
--- a/activesupport/test/core_ext/module_test.rb
+++ b/activesupport/test/core_ext/module_test.rb
@@ -142,7 +142,7 @@ class ModuleTest < Test::Unit::TestCase
 
   def test_delegation_without_allow_nil_and_nil_value
     david = Someone.new("David")
-    assert_raise(NoMethodError) { david.street }
+    assert_raise(RuntimeError) { david.street }
   end
 
   def test_parent