From 1092c181b5568d06e84f6a3253aaca81c02a2b2c Mon Sep 17 00:00:00 2001
From: Josh Susser <josh@hasmanythrough.com>
Date: Mon, 25 Aug 2008 21:28:53 -0700
Subject: [PATCH] add dynamic finder bang version to raise RecordNotFound

[#905 state:resolved]

Signed-off-by: Jeremy Kemper <jeremy@bitsweat.net>
---
 activerecord/lib/active_record/base.rb             |  4 +++-
 .../lib/active_record/dynamic_finder_match.rb      |  7 +++++++
 activerecord/test/cases/finder_test.rb             | 14 ++++++++++++++
 3 files changed, 24 insertions(+), 1 deletion(-)

diff --git a/activerecord/lib/active_record/base.rb b/activerecord/lib/active_record/base.rb
index 523b619e62..5c30f80555 100644
--- a/activerecord/lib/active_record/base.rb
+++ b/activerecord/lib/active_record/base.rb
@@ -1679,6 +1679,7 @@ module ActiveRecord #:nodoc:
             super unless all_attributes_exists?(attribute_names)
             if match.finder?
               finder = match.finder
+              bang = match.bang?
               self.class_eval %{
                 def self.#{method_id}(*args)
                   options = args.extract_options!
@@ -1687,13 +1688,14 @@ module ActiveRecord #:nodoc:
                   validate_find_options(options)
                   set_readonly_option!(options)
 
-                  if options[:conditions]
+                  #{'result = ' if bang}if options[:conditions]
                     with_scope(:find => finder_options) do
                       ActiveSupport::Deprecation.silence { send(:#{finder}, options) }
                     end
                   else
                     ActiveSupport::Deprecation.silence { send(:#{finder}, options.merge(finder_options)) }
                   end
+                  #{'result || raise(RecordNotFound)' if bang}
                 end
               }, __FILE__, __LINE__
               send(method_id, *arguments)
diff --git a/activerecord/lib/active_record/dynamic_finder_match.rb b/activerecord/lib/active_record/dynamic_finder_match.rb
index 4618e777a4..b105b919f5 100644
--- a/activerecord/lib/active_record/dynamic_finder_match.rb
+++ b/activerecord/lib/active_record/dynamic_finder_match.rb
@@ -11,6 +11,9 @@ module ActiveRecord
       when /^find_(all_by|by)_([_a-zA-Z]\w*)$/
         @finder = :find_every if $1 == 'all_by'
         names = $2
+      when /^find_by_([_a-zA-Z]\w*)\!$/
+        @bang = true
+        names = $1
       when /^find_or_(initialize|create)_by_([_a-zA-Z]\w*)$/
         @instantiator = $1 == 'initialize' ? :new : :create
         names = $2
@@ -29,5 +32,9 @@ module ActiveRecord
     def instantiator?
       @finder == :find_initial && !@instantiator.nil?
     end
+
+    def bang?
+      @bang
+    end
   end
 end
diff --git a/activerecord/test/cases/finder_test.rb b/activerecord/test/cases/finder_test.rb
index 875d56f6c1..2ce49ed76f 100644
--- a/activerecord/test/cases/finder_test.rb
+++ b/activerecord/test/cases/finder_test.rb
@@ -25,6 +25,15 @@ class DynamicFinderMatchTest < ActiveRecord::TestCase
     assert_equal %w(age sex location), match.attribute_names
   end
 
+  def find_by_bang
+    match = ActiveRecord::DynamicFinderMatch.match("find_by_age_and_sex_and_location!")
+    assert_not_nil match
+    assert match.finder?
+    assert match.bang?
+    assert_equal :find_initial, match.finder
+    assert_equal %w(age sex location), match.attribute_names
+  end
+
   def test_find_all_by
     match = ActiveRecord::DynamicFinderMatch.match("find_all_by_age_and_sex_and_location")
     assert_not_nil match
@@ -482,6 +491,11 @@ class FinderTest < ActiveRecord::TestCase
     assert_nil Topic.find_by_title("The First Topic!")
   end
 
+  def test_find_by_one_attribute_bang
+    assert_equal topics(:first), Topic.find_by_title!("The First Topic")
+    assert_raises(ActiveRecord::RecordNotFound) { Topic.find_by_title!("The First Topic!") }
+  end
+
   def test_find_by_one_attribute_caches_dynamic_finder
     # ensure this test can run independently of order
     class << Topic; self; end.send(:remove_method, :find_by_title) if Topic.public_methods.any? { |m| m.to_s == 'find_by_title' }