Remove `Column#primary`

It appears to have been used at some point in the past, but is no longer
used in any meaningful way. Whether a column is considered primary is
a property of the model, not the schema/column. This also removes the
need for yet another layer of caching of the model's schema, and we can
leave that to the schema cache.

4 files changed, 5 insertions, 40 deletions

diff --git a/activerecord/test/cases/adapters/sqlite3/copy_table_test.rb b/activerecord/test/cases/adapters/sqlite3/copy_table_test.rb
index b478db749d..13b754d226 100644
--- a/activerecord/test/cases/adapters/sqlite3/copy_table_test.rb
+++ b/activerecord/test/cases/adapters/sqlite3/copy_table_test.rb
@@ -60,7 +60,6 @@ class CopyTableTest < ActiveRecord::TestCase
       assert_equal original_id.type, copied_id.type
       assert_equal original_id.sql_type, copied_id.sql_type
       assert_equal original_id.limit, copied_id.limit
-      assert_equal original_id.primary, copied_id.primary
     end
   end
 
diff --git a/activerecord/test/cases/base_test.rb b/activerecord/test/cases/base_test.rb
index 7c7c1fbfbd..c565daba65 100644
--- a/activerecord/test/cases/base_test.rb
+++ b/activerecord/test/cases/base_test.rb
@@ -102,8 +102,8 @@ class BasicsTest < ActiveRecord::TestCase
   end
 
   def test_columns_should_obey_set_primary_key
-    pk = Subscriber.columns.find { |x| x.name == 'nick' }
-    assert pk.primary, 'nick should be primary key'
+    pk = Subscriber.columns_hash[Subscriber.primary_key]
+    assert_equal 'nick', pk.name, 'nick should be primary key'
   end
 
   def test_primary_key_with_no_id
diff --git a/activerecord/test/cases/bind_parameter_test.rb b/activerecord/test/cases/bind_parameter_test.rb
index 40f73cd68c..0bc7ee6d64 100644
--- a/activerecord/test/cases/bind_parameter_test.rb
+++ b/activerecord/test/cases/bind_parameter_test.rb
@@ -21,7 +21,7 @@ module ActiveRecord
       super
       @connection = ActiveRecord::Base.connection
       @subscriber   = LogListener.new
-      @pk         = Topic.columns.find { |c| c.primary }
+      @pk         = Topic.columns_hash[Topic.primary_key]
       @subscription = ActiveSupport::Notifications.subscribe('sql.active_record', @subscriber)
     end
 
@@ -60,12 +60,10 @@ module ActiveRecord
       end
 
       def test_logs_bind_vars
-        pk = Topic.columns.find { |x| x.primary }
-
         payload = {
           :name  => 'SQL',
           :sql   => 'select * from topics where id = ?',
-          :binds => [[pk, 10]]
+          :binds => [[@pk, 10]]
         }
         event  = ActiveSupport::Notifications::Event.new(
           'foo',
@@ -87,7 +85,7 @@ module ActiveRecord
         }.new
 
         logger.sql event
-        assert_match([[pk.name, 10]].inspect, logger.debugs.first)
+        assert_match([[@pk.name, 10]].inspect, logger.debugs.first)
       end
     end
   end
diff --git a/activerecord/test/cases/primary_keys_test.rb b/activerecord/test/cases/primary_keys_test.rb
index 56d0dd6a77..c719918fd7 100644
--- a/activerecord/test/cases/primary_keys_test.rb
+++ b/activerecord/test/cases/primary_keys_test.rb
@@ -149,38 +149,6 @@ class PrimaryKeysTest < ActiveRecord::TestCase
     assert_equal k.connection.quote_column_name("foo"), k.quoted_primary_key
   end
 
-  def test_two_models_with_same_table_but_different_primary_key
-    k1 = Class.new(ActiveRecord::Base)
-    k1.table_name = 'posts'
-    k1.primary_key = 'id'
-
-    k2 = Class.new(ActiveRecord::Base)
-    k2.table_name = 'posts'
-    k2.primary_key = 'title'
-
-    assert k1.columns.find { |c| c.name == 'id' }.primary
-    assert !k1.columns.find { |c| c.name == 'title' }.primary
-    assert k1.columns_hash['id'].primary
-    assert !k1.columns_hash['title'].primary
-
-    assert !k2.columns.find { |c| c.name == 'id' }.primary
-    assert k2.columns.find { |c| c.name == 'title' }.primary
-    assert !k2.columns_hash['id'].primary
-    assert k2.columns_hash['title'].primary
-  end
-
-  def test_models_with_same_table_have_different_columns
-    k1 = Class.new(ActiveRecord::Base)
-    k1.table_name = 'posts'
-
-    k2 = Class.new(ActiveRecord::Base)
-    k2.table_name = 'posts'
-
-    k1.columns.zip(k2.columns).each do |col1, col2|
-      assert !col1.equal?(col2)
-    end
-  end
-
   def test_auto_detect_primary_key_from_schema
     MixedCaseMonkey.reset_primary_key
     assert_equal "monkeyID", MixedCaseMonkey.primary_key