AR::RecordNotSaved & RecordNotDestroyed should include an error message

When `AR::Base.save!` or `AR::Base.destroy!` is called and an exception
is raised, the exception doesn't have any error message or has a weird
message like `#<FailedBulb:0x0000000907b4b8>`. Give a better message so
we can easily understand why it's failing to save/destroy.

2 files changed, 4 insertions, 1 deletions

diff --git a/activerecord/test/cases/associations/has_many_associations_test.rb b/activerecord/test/cases/associations/has_many_associations_test.rb
index 14cdf37f46..2c4e2a875c 100644
--- a/activerecord/test/cases/associations/has_many_associations_test.rb
+++ b/activerecord/test/cases/associations/has_many_associations_test.rb
@@ -2131,11 +2131,12 @@ class HasManyAssociationsTest < ActiveRecord::TestCase
     car = Car.create!
     original_child = FailedBulb.create!(car: car)
 
-    assert_raise(ActiveRecord::RecordNotDestroyed) do
+    error = assert_raise(ActiveRecord::RecordNotDestroyed) do
       car.failed_bulbs = [FailedBulb.create!]
     end
 
     assert_equal [original_child], car.reload.failed_bulbs
+    assert_equal "Failed to destroy the record", error.message
   end
 
   test 'updates counter cache when default scope is given' do
diff --git a/activerecord/test/cases/callbacks_test.rb b/activerecord/test/cases/callbacks_test.rb
index 3ae4a6eade..73ac30e547 100644
--- a/activerecord/test/cases/callbacks_test.rb
+++ b/activerecord/test/cases/callbacks_test.rb
@@ -451,6 +451,7 @@ class CallbacksTest < ActiveRecord::TestCase
       assert !david.save
       exc = assert_raise(ActiveRecord::RecordNotSaved) { david.save! }
       assert_equal exc.record, david
+      assert_equal "Failed to save the record", exc.message
     end
 
     david = ImmutableDeveloper.find(1)
@@ -494,6 +495,7 @@ class CallbacksTest < ActiveRecord::TestCase
       assert !david.destroy
       exc = assert_raise(ActiveRecord::RecordNotDestroyed) { david.destroy! }
       assert_equal exc.record, david
+      assert_equal "Failed to destroy the record", exc.message
     end
     assert_not_nil ImmutableDeveloper.find_by_id(1)