Dont simply assume a type is a valid database type. This is only always true in the case of sqlite.

Others adapters need to perform a check for validity.
Add coverage for mysql2 db type validation

3 files changed, 16 insertions, 1 deletions

diff --git a/activerecord/lib/active_record/connection_adapters/abstract_adapter.rb b/activerecord/lib/active_record/connection_adapters/abstract_adapter.rb
index 86de8f1ca0..373c082f65 100644
--- a/activerecord/lib/active_record/connection_adapters/abstract_adapter.rb
+++ b/activerecord/lib/active_record/connection_adapters/abstract_adapter.rb
@@ -154,7 +154,7 @@ module ActiveRecord
       end
 
       def valid_type?(type)
-        true
+        false
       end
 
       def schema_creation
diff --git a/activerecord/lib/active_record/connection_adapters/sqlite3_adapter.rb b/activerecord/lib/active_record/connection_adapters/sqlite3_adapter.rb
index 1d7ce92b29..e3793e6c77 100644
--- a/activerecord/lib/active_record/connection_adapters/sqlite3_adapter.rb
+++ b/activerecord/lib/active_record/connection_adapters/sqlite3_adapter.rb
@@ -154,6 +154,10 @@ module ActiveRecord
         true
       end
 
+      def valid_type?(type)
+        true
+      end
+
       # Returns 62. SQLite supports index names up to 64
       # characters. The rest is used by rails internally to perform
       # temporary rename operations
diff --git a/activerecord/test/cases/adapters/mysql2/mysql2_adapter_test.rb b/activerecord/test/cases/adapters/mysql2/mysql2_adapter_test.rb
index 00d23740b6..61dd0828d0 100644
--- a/activerecord/test/cases/adapters/mysql2/mysql2_adapter_test.rb
+++ b/activerecord/test/cases/adapters/mysql2/mysql2_adapter_test.rb
@@ -17,6 +17,17 @@ class Mysql2AdapterTest < ActiveRecord::Mysql2TestCase
     end
   end
 
+  def test_valid_column
+    with_example_table do
+      column = @conn.columns('ex').find { |col| col.name == 'id' }
+      assert @conn.valid_type?(column.type)
+    end
+  end
+
+  def test_invalid_column
+    assert_not @conn.valid_type?(:foobar)
+  end
+
   def test_columns_for_distinct_zero_orders
     assert_equal "posts.id",
       @conn.columns_for_distinct("posts.id", [])