backport #8176, `#pluck` can be used on a relation with `select` clause. #8209

Merged
merged 1 commit into from Nov 13, 2012
9 activerecord/CHANGELOG.md
@@ -1,5 +1,14 @@
## Rails 3.2.10 (unreleased)
+* `#pluck` can be used on a relation with `select` clause. [Backport #8176]
+ Fix #7551
+
+ Example:
+
+ Topic.select([:approved, :id]).order(:id).pluck(:id)
+
+ *Yves Senn*
+
* Do not create useless database transaction when building `has_one` association. [Backport #8154]
Example:
View
4 activerecord/lib/active_record/relation/calculations.rb
@@ -178,7 +178,9 @@ def calculate(operation, column_name, options = {})
#
def pluck(column_name)
column_name = column_name.to_s
- klass.connection.select_all(select(column_name).arel).map! do |attributes|
+ relation = clone
+ relation.select_values = [column_name]
+ klass.connection.select_all(relation.arel).map! do |attributes|
klass.type_cast_attribute(attributes.keys.first, klass.initialize_attributes(attributes))
end
end
View
6 activerecord/test/cases/calculations_test.rb
@@ -487,4 +487,10 @@ def test_pluck_with_serialization
def test_pluck_with_qualified_column_name
assert_equal [1,2,3,4], Topic.order(:id).pluck("topics.id")
end
+
+ def test_pluck_replaces_select_clause
+ taks_relation = Topic.select([:approved, :id]).order(:id)
+ assert_equal [1,2,3,4], taks_relation.pluck(:id)
+ assert_equal [false, true, true, true], taks_relation.pluck(:approved)
+ end
end