Relation#readonly(false) should toggle the readonly flag

2 files changed, 10 insertions, 5 deletions

diff --git a/activerecord/lib/active_record/relation.rb b/activerecord/lib/active_record/relation.rb
index a7f62abe1d..ff10df96f2 100644
--- a/activerecord/lib/active_record/relation.rb
+++ b/activerecord/lib/active_record/relation.rb
@@ -35,12 +35,17 @@ module ActiveRecord
       create_new_relation(@relation, @readonly, @associations_to_preload, @eager_load_associations + Array.wrap(associations))
     end
 
-    def readonly
-      create_new_relation(@relation, true)
+    def readonly(status = true)
+      status.nil? ? create_new_relation : create_new_relation(@relation, status)
     end
 
     def select(selects)
-      selects.present? ? create_new_relation(@relation.project(selects)) : create_new_relation
+      if selects.present?
+        frozen = @relation.joins(relation).present? ? false : @readonly
+        create_new_relation(@relation.project(selects), frozen)
+      else
+        create_new_relation
+      end
     end
 
     def from(from)
@@ -106,7 +111,7 @@ module ActiveRecord
         @relation.join(join, join_type)
       end
 
-      create_new_relation(join_relation)
+      create_new_relation(join_relation, true)
     end
 
     def where(*args)
diff --git a/activerecord/test/cases/associations/inner_join_association_test.rb b/activerecord/test/cases/associations/inner_join_association_test.rb
index 6220fab383..18a1cd3cd0 100644
--- a/activerecord/test/cases/associations/inner_join_association_test.rb
+++ b/activerecord/test/cases/associations/inner_join_association_test.rb
@@ -64,7 +64,7 @@ class InnerJoinAssociationTest < ActiveRecord::TestCase
   end
 
   def test_find_with_implicit_inner_joins_honors_readonly_false
-    authors = Author.find(:all, :joins => :posts, :readonly => false)
+    authors = Author.joins(:posts).readonly(false).to_a
     assert !authors.empty?, "expected authors to be non-empty"
     assert authors.all? {|a| !a.readonly? }, "expected no authors to be readonly"
   end