Improve PostgreSQL adapter schema-awareness

* table_exists? scoped by schema search path unless schema is explicitly named. Added tests and doc to clarify the behaviour
* extract_schema_and_table tests and implementation extended to cover all cases
* primary_key does not ignore schema information
* add current_schema and schema_exists? methods
* more robust table referencing in insert_sql and sql_for_insert methods

1 files changed, 39 insertions, 0 deletions

diff --git a/activerecord/test/cases/adapters/postgresql/postgresql_adapter_test.rb b/activerecord/test/cases/adapters/postgresql/postgresql_adapter_test.rb
index 7c49236854..b113267dca 100644
--- a/activerecord/test/cases/adapters/postgresql/postgresql_adapter_test.rb
+++ b/activerecord/test/cases/adapters/postgresql/postgresql_adapter_test.rb
@@ -10,6 +10,45 @@ module ActiveRecord
         @connection.exec_query('create table ex(id serial primary key, number integer, data character varying(255))')
       end
 
+      def test_primary_key
+        assert_equal 'id',@connection.primary_key('ex')
+      end
+
+      def test_non_standard_primary_key
+        @connection.exec_query('drop table if exists ex')
+        @connection.exec_query('create table ex(data character varying(255) primary key)')
+        assert_equal 'data', @connection.primary_key('ex')
+      end
+
+      def test_primary_key_returns_nil_for_no_pk
+        @connection.exec_query('drop table if exists ex')
+        @connection.exec_query('create table ex(id integer)')
+        assert_nil @connection.primary_key('ex')
+      end
+
+      def test_primary_key_raises_error_if_table_not_found
+        assert_raises(ActiveRecord::StatementInvalid) do
+          @connection.primary_key('unobtainium')
+        end
+      end
+
+      def test_insert_sql_with_proprietary_returning_clause
+        id = @connection.insert_sql("insert into ex (number) values(5150)", nil, "number")
+        assert_equal "5150", id
+      end
+
+      def test_insert_sql_with_quoted_schema_and_table_name
+        id = @connection.insert_sql('insert into "public"."ex" (number) values(5150)')
+        expect = @connection.query('select max(id) from ex').first.first
+        assert_equal expect, id
+      end
+
+      def test_insert_sql_with_no_space_after_table_name
+        id = @connection.insert_sql("insert into ex(number) values(5150)")
+        expect = @connection.query('select max(id) from ex').first.first
+        assert_equal expect, id
+      end
+
       def test_serial_sequence
         assert_equal 'public.accounts_id_seq',
           @connection.serial_sequence('accounts', 'id')