Translate foreign key violations to ActiveRecord::InvalidForeignKey exceptions.

Signed-off-by: Michael Koziarski <michael@koziarski.com>

3 files changed, 8 insertions, 0 deletions

diff --git a/activerecord/lib/active_record/base.rb b/activerecord/lib/active_record/base.rb
index defe1b56b6..027ab8af9e 100755
--- a/activerecord/lib/active_record/base.rb
+++ b/activerecord/lib/active_record/base.rb
@@ -71,6 +71,10 @@ module ActiveRecord #:nodoc:
   class RecordNotUnique < StatementInvalid
   end
 
+  # Raised when a record cannot be inserted or updated because it references a non-existent record.
+  class InvalidForeignKey < StatementInvalid
+  end
+
   # Raised when number of bind variables in statement given to <tt>:condition</tt> key (for example, when using +find+ method)
   # does not match number of expected variables.
   #
diff --git a/activerecord/lib/active_record/connection_adapters/mysql_adapter.rb b/activerecord/lib/active_record/connection_adapters/mysql_adapter.rb
index 59bf01e774..ae065e6bc1 100644
--- a/activerecord/lib/active_record/connection_adapters/mysql_adapter.rb
+++ b/activerecord/lib/active_record/connection_adapters/mysql_adapter.rb
@@ -569,6 +569,8 @@ module ActiveRecord
           case exception.errno
           when 1062
             RecordNotUnique.new(message)
+          when 1452
+            InvalidForeignKey.new(message)
           else
             super
           end
diff --git a/activerecord/lib/active_record/connection_adapters/postgresql_adapter.rb b/activerecord/lib/active_record/connection_adapters/postgresql_adapter.rb
index e990052e09..24482aa19a 100644
--- a/activerecord/lib/active_record/connection_adapters/postgresql_adapter.rb
+++ b/activerecord/lib/active_record/connection_adapters/postgresql_adapter.rb
@@ -945,6 +945,8 @@ module ActiveRecord
           case exception.message
           when /duplicate key value violates unique constraint/
             RecordNotUnique.new(message)
+          when /violates foreign key constraint/
+            InvalidForeignKey.new(message)
           else
             super
           end