`TimeWithZone` raises `NoMethodError` in proper context.

Closes #9772.

`TimeWithZone` delegates everything to the wrapped `Time` object
using `method_missing`. The result is that `NoMethodError` error
will be raised in the context of `Time` which leads to a misleading
debug output.

3 files changed, 15 insertions, 0 deletions

diff --git a/activesupport/CHANGELOG.md b/activesupport/CHANGELOG.md
index 9e6b77e2f3..b629688591 100644
--- a/activesupport/CHANGELOG.md
+++ b/activesupport/CHANGELOG.md
@@ -1,5 +1,10 @@
 ## Rails 4.0.0 (unreleased) ##
 
+*   `ActiveSupport::TimeWithZone` raises `NoMethodError` in proper context.
+    Fixes #9772.
+
+    *Yves Senn*
+
 *   Fix deletion of empty directories in `ActiveSupport::Cache::FileStore`.
 
     *Charles Jones*
diff --git a/activesupport/lib/active_support/time_with_zone.rb b/activesupport/lib/active_support/time_with_zone.rb
index 98c866ac43..4a032b0ad0 100644
--- a/activesupport/lib/active_support/time_with_zone.rb
+++ b/activesupport/lib/active_support/time_with_zone.rb
@@ -366,6 +366,8 @@ module ActiveSupport
     # TimeWithZone with the existing +time_zone+.
     def method_missing(sym, *args, &block)
       wrap_with_time_zone time.__send__(sym, *args, &block)
+    rescue NoMethodError => e
+      raise e, e.message.sub(time.inspect, self.inspect), e.backtrace
     end
 
     private
diff --git a/activesupport/test/core_ext/time_with_zone_test.rb b/activesupport/test/core_ext/time_with_zone_test.rb
index 0f5699fd63..98a87ab9e6 100644
--- a/activesupport/test/core_ext/time_with_zone_test.rb
+++ b/activesupport/test/core_ext/time_with_zone_test.rb
@@ -779,6 +779,14 @@ class TimeWithZoneTest < ActiveSupport::TestCase
     assert_equal "Sun, 15 Jul 2007 10:30:00 EDT -04:00", (twz - 1.year).inspect
   end
 
+  def test_no_method_error_has_proper_context
+    e = assert_raises(NoMethodError) {
+      @twz.this_method_does_not_exist
+    }
+    assert_equal "undefined method `this_method_does_not_exist' for Fri, 31 Dec 1999 19:00:00 EST -05:00:Time", e.message
+    assert_no_match "rescue", e.backtrace.first
+  end
+
   protected
     def with_env_tz(new_tz = 'US/Eastern')
       old_tz, ENV['TZ'] = ENV['TZ'], new_tz