Raise custom error on empty join

2 files changed, 16 insertions, 0 deletions

diff --git a/test/test_select_manager.rb b/test/test_select_manager.rb
index 9a225edeec..e88f0e8e11 100644
--- a/test/test_select_manager.rb
+++ b/test/test_select_manager.rb
@@ -618,6 +618,16 @@ module Arel
         manager   = Arel::SelectManager.new
         manager.join(nil).must_equal manager
       end
+
+      it 'raises EmptyJoinError on empty' do
+        left      = Table.new :users
+        manager   = Arel::SelectManager.new
+
+        manager.from left
+        assert_raises(EmptyJoinError) do
+          manager.join("")
+        end
+      end
     end
 
     describe 'outer join' do
diff --git a/test/test_table.rb b/test/test_table.rb
index 168fde370d..e36a6e3a41 100644
--- a/test/test_table.rb
+++ b/test/test_table.rb
@@ -71,6 +71,12 @@ module Arel
           mgr.to_sql.must_be_like %{ SELECT FROM "users" }
         end
 
+        it 'raises EmptyJoinError on empty' do
+          assert_raises(EmptyJoinError) do
+            @relation.join ""
+          end
+        end
+
         it 'takes a second argument for join type' do
           right     = @relation.alias
           predicate = @relation[:id].eq(right[:id])