diff options
Diffstat (limited to 'activerecord')
6 files changed, 46 insertions, 10 deletions
diff --git a/activerecord/lib/active_record/associations/singular_association.rb b/activerecord/lib/active_record/associations/singular_association.rb index 0d8e45adb5..4edbe216be 100644 --- a/activerecord/lib/active_record/associations/singular_association.rb +++ b/activerecord/lib/active_record/associations/singular_association.rb @@ -37,7 +37,7 @@ module ActiveRecord # Implemented by subclasses def replace(record) - raise NotImplementedError + raise NotImplementedError, "Subclasses must implement a replace(record) method" end def set_new_record(record) diff --git a/activerecord/lib/active_record/locking/optimistic.rb b/activerecord/lib/active_record/locking/optimistic.rb index 6b2b1ebafe..9a31675782 100644 --- a/activerecord/lib/active_record/locking/optimistic.rb +++ b/activerecord/lib/active_record/locking/optimistic.rb @@ -23,7 +23,7 @@ module ActiveRecord # p2.first_name = "should fail" # p2.save # Raises a ActiveRecord::StaleObjectError # - # Optimistic locking will also check for stale data when objects are destroyed. Example: + # Optimistic locking will also check for stale data when objects are destroyed. Example: # # p1 = Person.find(1) # p2 = Person.find(1) diff --git a/activerecord/lib/active_record/locking/pessimistic.rb b/activerecord/lib/active_record/locking/pessimistic.rb index 557b277d6b..862cf8f72a 100644 --- a/activerecord/lib/active_record/locking/pessimistic.rb +++ b/activerecord/lib/active_record/locking/pessimistic.rb @@ -9,9 +9,8 @@ module ActiveRecord # Account.find(1, :lock => true) # # Pass <tt>:lock => 'some locking clause'</tt> to give a database-specific locking clause - # of your own such as 'LOCK IN SHARE MODE' or 'FOR UPDATE NOWAIT'. + # of your own such as 'LOCK IN SHARE MODE' or 'FOR UPDATE NOWAIT'. Example: # - # Example: # Account.transaction do # # select * from accounts where name = 'shugo' limit 1 for update # shugo = Account.where("name = 'shugo'").lock(true).first @@ -24,6 +23,7 @@ module ActiveRecord # # You can also use ActiveRecord::Base#lock! method to lock one record by id. # This may be better if you don't need to lock every row. Example: + # # Account.transaction do # # select * from accounts where ... # accounts = Account.where(...).all @@ -44,7 +44,7 @@ module ActiveRecord module Pessimistic # Obtain a row lock on this record. Reloads the record to obtain the requested # lock. Pass an SQL locking clause to append the end of the SELECT statement - # or pass true for "FOR UPDATE" (the default, an exclusive row lock). Returns + # or pass true for "FOR UPDATE" (the default, an exclusive row lock). Returns # the locked record. def lock!(lock = true) reload(:lock => lock) if persisted? diff --git a/activerecord/lib/active_record/relation.rb b/activerecord/lib/active_record/relation.rb index 5af20bf38b..371403f510 100644 --- a/activerecord/lib/active_record/relation.rb +++ b/activerecord/lib/active_record/relation.rb @@ -110,7 +110,10 @@ module ActiveRecord # Returns true if there are no records. def empty? - loaded? ? @records.empty? : count.zero? + return @records.empty? if loaded? + + c = count + c.respond_to?(:zero?) ? c.zero? : c.empty? end def any? diff --git a/activerecord/lib/active_record/validations/uniqueness.rb b/activerecord/lib/active_record/validations/uniqueness.rb index a96796f9ff..9cd6c26322 100644 --- a/activerecord/lib/active_record/validations/uniqueness.rb +++ b/activerecord/lib/active_record/validations/uniqueness.rb @@ -173,10 +173,17 @@ module ActiveRecord # This technique is also known as optimistic concurrency control: # http://en.wikipedia.org/wiki/Optimistic_concurrency_control # - # Active Record currently provides no way to distinguish unique - # index constraint errors from other types of database errors, so you - # will have to parse the (database-specific) exception message to detect - # such a case. + # The bundled ActiveRecord::ConnectionAdapters distinguish unique index + # constraint errors from other types of database errors by throwing an + # ActiveRecord::RecordNotUnique exception. + # For other adapters you will have to parse the (database-specific) exception + # message to detect such a case. + # The following bundled adapters throw the ActiveRecord::RecordNotUnique exception: + # * ActiveRecord::ConnectionAdapters::MysqlAdapter + # * ActiveRecord::ConnectionAdapters::Mysql2Adapter + # * ActiveRecord::ConnectionAdapters::SQLiteAdapter + # * ActiveRecord::ConnectionAdapters::SQLite3Adapter + # * ActiveRecord::ConnectionAdapters::PostgreSQLAdapter # def validates_uniqueness_of(*attr_names) validates_with UniquenessValidator, _merge_attributes(attr_names) diff --git a/activerecord/test/cases/relations_test.rb b/activerecord/test/cases/relations_test.rb index ac586e2a63..680e1d50cf 100644 --- a/activerecord/test/cases/relations_test.rb +++ b/activerecord/test/cases/relations_test.rb @@ -673,6 +673,32 @@ class RelationTest < ActiveRecord::TestCase assert_equal expected, posts.count end + def test_empty + posts = Post.scoped + + assert_queries(1) { assert_equal false, posts.empty? } + assert ! posts.loaded? + + no_posts = posts.where(:title => "") + assert_queries(1) { assert_equal true, no_posts.empty? } + assert ! no_posts.loaded? + + best_posts = posts.where(:comments_count => 0) + best_posts.to_a # force load + assert_no_queries { assert_equal false, best_posts.empty? } + end + + def test_empty_complex_chained_relations + posts = Post.select("comments_count").where("id is not null").group("author_id").where("comments_count > 0") + + assert_queries(1) { assert_equal false, posts.empty? } + assert ! posts.loaded? + + no_posts = posts.where(:title => "") + assert_queries(1) { assert_equal true, no_posts.empty? } + assert ! no_posts.loaded? + end + def test_any posts = Post.scoped |