Merge pull request #25107 from Erol/introduce-new-ar-transaction-error-classes

Introduce new ActiveRecord transaction error classes

Closes #26018

2 files changed, 40 insertions, 22 deletions

diff --git a/activerecord/test/cases/adapters/mysql2/transaction_test.rb b/activerecord/test/cases/adapters/mysql2/transaction_test.rb
index 0e37c70e5c..1a88b9cbca 100644
--- a/activerecord/test/cases/adapters/mysql2/transaction_test.rb
+++ b/activerecord/test/cases/adapters/mysql2/transaction_test.rb
@@ -27,32 +27,25 @@ module ActiveRecord
       @connection.drop_table 'samples', if_exists: true
     end
 
-    test "raises error when a serialization failure occurs" do
-      assert_raises(ActiveRecord::TransactionSerializationError) do
-        thread = Thread.new do
-          Sample.transaction isolation: :serializable do
-            Sample.delete_all
-
-            10.times do |i|
-              sleep 0.1
+    test "raises DeadlockDetected when a deadlock is encountered" do
+      assert_raises(ActiveRecord::DeadlockDetected) do
+        s1 = Sample.create value: 1
+        s2 = Sample.create value: 2
 
-              Sample.create value: i
-            end
+        thread = Thread.new do
+          Sample.transaction do
+            s1.lock!
+            sleep 1
+            s2.update_attributes value: 1
           end
         end
 
-        sleep 0.1
-
-        Sample.transaction isolation: :serializable do
-          Sample.delete_all
-
-          10.times do |i|
-            sleep 0.1
-
-            Sample.create value: i
-          end
+        sleep 0.5
 
+        Sample.transaction do
+          s2.lock!
           sleep 1
+          s1.update_attributes value: 2
         end
 
         thread.join
diff --git a/activerecord/test/cases/adapters/postgresql/transaction_test.rb b/activerecord/test/cases/adapters/postgresql/transaction_test.rb
index e76705a802..87d1fffe19 100644
--- a/activerecord/test/cases/adapters/postgresql/transaction_test.rb
+++ b/activerecord/test/cases/adapters/postgresql/transaction_test.rb
@@ -26,9 +26,9 @@ module ActiveRecord
       @connection.drop_table 'samples', if_exists: true
     end
 
-    test "raises error when a serialization failure occurs" do
+    test "raises SerializationFailure when a serialization failure occurs" do
       with_warning_suppression do
-        assert_raises(ActiveRecord::TransactionSerializationError) do
+        assert_raises(ActiveRecord::SerializationFailure) do
           thread = Thread.new do
             Sample.transaction isolation: :serializable do
               Sample.delete_all
@@ -51,8 +51,33 @@ module ActiveRecord
 
               Sample.create value: i
             end
+          end
+
+          thread.join
+        end
+      end
+    end
+
+    test "raises DeadlockDetected when a deadlock is encountered" do
+      with_warning_suppression do
+        assert_raises(ActiveRecord::DeadlockDetected) do
+          s1 = Sample.create value: 1
+          s2 = Sample.create value: 2
+
+          thread = Thread.new do
+            Sample.transaction do
+              s1.lock!
+              sleep 1
+              s2.update_attributes value: 1
+            end
+          end
+
+          sleep 0.5
 
+          Sample.transaction do
+            s2.lock!
             sleep 1
+            s1.update_attributes value: 2
           end
 
           thread.join