introduce `connection.supports_views?` and basic view tests.

`AbstractAdapter#supports_views?` defaults to `false` so we have to turn it on
in adapter subclasses. Currently the flag only controls test execution.

/cc @yahonda

1 files changed, 42 insertions, 0 deletions

diff --git a/activerecord/test/cases/view_test.rb b/activerecord/test/cases/view_test.rb
new file mode 100644
index 0000000000..aef6ad2296
--- /dev/null
+++ b/activerecord/test/cases/view_test.rb
@@ -0,0 +1,42 @@
+require "cases/helper"
+require "models/book"
+
+if ActiveRecord::Base.connection.supports_views?
+class ViewWithPrimaryKeyTest < ActiveRecord::TestCase
+  fixtures :books
+
+  class Ebook < ActiveRecord::Base
+    self.primary_key = "id"
+  end
+
+  setup do
+    @connection = ActiveRecord::Base.connection
+    @connection.execute <<-SQL
+      CREATE VIEW ebooks
+        AS SELECT id, name, status FROM books WHERE format = 'ebook'
+    SQL
+  end
+
+  teardown do
+    @connection.execute "DROP VIEW IF EXISTS ebooks"
+  end
+
+  def test_reading
+    books = Ebook.all
+    assert_equal [books(:rfr).id], books.map(&:id)
+    assert_equal ["Ruby for Rails"], books.map(&:name)
+  end
+
+  def test_table_exists
+    skip "SQLite does not currently treat views as tables" if current_adapter?(:SQLite3Adapter)
+    view_name = Ebook.table_name
+    assert @connection.table_exists?(view_name), "'#{view_name}' table should exist"
+  end
+
+  def test_column_definitions
+    assert_equal([["id", :integer],
+                  ["name", :string],
+                  ["status", :integer]], Ebook.columns.map { |c| [c.name, c.type] })
+  end
+end
+end