6 files changed, 58 insertions, 23 deletions
diff --git a/activerecord/test/cases/associations/eager_test.rb b/activerecord/test/cases/associations/eager_test.rb
index 7d054b874b..11f4aae5b3 100644
--- a/activerecord/test/cases/associations/eager_test.rb
+++ b/activerecord/test/cases/associations/eager_test.rb
@@ -739,18 +739,25 @@ class EagerAssociationTest < ActiveRecord::TestCase
   end
 
   def test_eager_with_invalid_association_reference
-    assert_raise(ActiveRecord::AssociationNotFoundError, "Association was not found; perhaps you misspelled it?  You specified :include => :monkeys") {
+    e = assert_raise(ActiveRecord::AssociationNotFoundError) {
       Post.all.merge!(includes: :monkeys).find(6)
     }
-    assert_raise(ActiveRecord::AssociationNotFoundError, "Association was not found; perhaps you misspelled it?  You specified :include => :monkeys") {
+    assert_equal("Association named 'monkeys' was not found on Post; perhaps you misspelled it?", e.message)
+
+    e = assert_raise(ActiveRecord::AssociationNotFoundError) {
       Post.all.merge!(includes: [ :monkeys ]).find(6)
     }
-    assert_raise(ActiveRecord::AssociationNotFoundError, "Association was not found; perhaps you misspelled it?  You specified :include => :monkeys") {
+    assert_equal("Association named 'monkeys' was not found on Post; perhaps you misspelled it?", e.message)
+
+    e = assert_raise(ActiveRecord::AssociationNotFoundError) {
       Post.all.merge!(includes: [ "monkeys" ]).find(6)
     }
-    assert_raise(ActiveRecord::AssociationNotFoundError, "Association was not found; perhaps you misspelled it?  You specified :include => :monkeys, :elephants") {
+    assert_equal("Association named 'monkeys' was not found on Post; perhaps you misspelled it?", e.message)
+
+    e = assert_raise(ActiveRecord::AssociationNotFoundError) {
       Post.all.merge!(includes: [ :monkeys, :elephants ]).find(6)
     }
+    assert_equal("Association named 'monkeys' was not found on Post; perhaps you misspelled it?", e.message)
   end
 
   def test_eager_has_many_through_with_order
diff --git a/activerecord/test/cases/coders/yaml_column_test.rb b/activerecord/test/cases/coders/yaml_column_test.rb
index b9c6224425..1e0b4580af 100644
--- a/activerecord/test/cases/coders/yaml_column_test.rb
+++ b/activerecord/test/cases/coders/yaml_column_test.rb
@@ -5,46 +5,48 @@ module ActiveRecord
   module Coders
     class YAMLColumnTest < ActiveRecord::TestCase
       def test_initialize_takes_class
-        coder = YAMLColumn.new(Object)
+        coder = YAMLColumn.new("attr_name", Object)
         assert_equal Object, coder.object_class
       end
 
       def test_type_mismatch_on_different_classes_on_dump
-        coder = YAMLColumn.new(Array)
-        assert_raises(SerializationTypeMismatch) do
+        coder = YAMLColumn.new("attr_name", Array)
+        error = assert_raises(SerializationTypeMismatch) do
           coder.dump("a")
         end
+        assert_equal %{Attribute `attr_name` was supposed to be a Array, but was a String. -- "a"}, error.to_s
       end
 
       def test_type_mismatch_on_different_classes
-        coder = YAMLColumn.new(Array)
-        assert_raises(SerializationTypeMismatch) do
+        coder = YAMLColumn.new("attr_name", Array)
+        error = assert_raises(SerializationTypeMismatch) do
           coder.load "--- foo"
         end
+        assert_equal %{Attribute `attr_name` was supposed to be a Array, but was a String. -- "foo"}, error.to_s
       end
 
       def test_nil_is_ok
-        coder = YAMLColumn.new
+        coder = YAMLColumn.new("attr_name")
         assert_nil coder.load "--- "
       end
 
       def test_returns_new_with_different_class
-        coder = YAMLColumn.new SerializationTypeMismatch
+        coder = YAMLColumn.new("attr_name", SerializationTypeMismatch)
         assert_equal SerializationTypeMismatch, coder.load("--- ").class
       end
 
       def test_returns_string_unless_starts_with_dash
-        coder = YAMLColumn.new
+        coder = YAMLColumn.new("attr_name")
         assert_equal "foo", coder.load("foo")
       end
 
       def test_load_handles_other_classes
-        coder = YAMLColumn.new
+        coder = YAMLColumn.new("attr_name")
         assert_equal [], coder.load([])
       end
 
       def test_load_doesnt_swallow_yaml_exceptions
-        coder = YAMLColumn.new
+        coder = YAMLColumn.new("attr_name")
         bad_yaml = "--- {"
         assert_raises(Psych::SyntaxError) do
           coder.load(bad_yaml)
@@ -52,7 +54,7 @@ module ActiveRecord
       end
 
       def test_load_doesnt_handle_undefined_class_or_module
-        coder = YAMLColumn.new
+        coder = YAMLColumn.new("attr_name")
         missing_class_yaml = '--- !ruby/object:DoesNotExistAndShouldntEver {}\n'
         assert_raises(ArgumentError) do
           coder.load(missing_class_yaml)
diff --git a/activerecord/test/cases/migration/compatibility_test.rb b/activerecord/test/cases/migration/compatibility_test.rb
index e5a7412bc3..9296f3da90 100644
--- a/activerecord/test/cases/migration/compatibility_test.rb
+++ b/activerecord/test/cases/migration/compatibility_test.rb
@@ -103,9 +103,10 @@ module ActiveRecord
       end
 
       def test_legacy_migrations_raises_exception_when_inherited
-        assert_raises(StandardError) do
-          Class.new(ActiveRecord::Migration)
+        e = assert_raises(StandardError) do
+          class_eval("class LegacyMigration < ActiveRecord::Migration; end")
         end
+        assert_match(/LegacyMigration < ActiveRecord::Migration\[4\.2\]/, e.message)
       end
     end
   end
diff --git a/activerecord/test/cases/migrator_test.rb b/activerecord/test/cases/migrator_test.rb
index 224e8d1854..20d70b75ac 100644
--- a/activerecord/test/cases/migrator_test.rb
+++ b/activerecord/test/cases/migrator_test.rb
@@ -45,10 +45,11 @@ class MigratorTest < ActiveRecord::TestCase
   end
 
   def test_migrator_with_duplicate_names
-    assert_raises(ActiveRecord::DuplicateMigrationNameError, "Multiple migrations have the name Chunky") do
+    e = assert_raises(ActiveRecord::DuplicateMigrationNameError) do
       list = [ActiveRecord::Migration.new("Chunky"), ActiveRecord::Migration.new("Chunky")]
       ActiveRecord::Migrator.new(:up, list)
     end
+    assert_match(/Multiple migrations have the name Chunky/, e.message)
   end
 
   def test_migrator_with_duplicate_versions
diff --git a/activerecord/test/cases/reflection_test.rb b/activerecord/test/cases/reflection_test.rb
index 2444eccab1..04ee67c177 100644
--- a/activerecord/test/cases/reflection_test.rb
+++ b/activerecord/test/cases/reflection_test.rb
@@ -258,7 +258,9 @@ class ReflectionTest < ActiveRecord::TestCase
       [Post.reflect_on_association(:first_taggings).scope],
       [Author.reflect_on_association(:misc_posts).scope]
     ]
-    actual = Author.reflect_on_association(:misc_post_first_blue_tags).scope_chain
+    actual = assert_deprecated do
+      Author.reflect_on_association(:misc_post_first_blue_tags).scope_chain
+    end
     assert_equal expected, actual
 
     expected = [
@@ -270,7 +272,9 @@ class ReflectionTest < ActiveRecord::TestCase
       [],
       []
     ]
-    actual = Author.reflect_on_association(:misc_post_first_blue_tags_2).scope_chain
+    actual = assert_deprecated do
+      Author.reflect_on_association(:misc_post_first_blue_tags_2).scope_chain
+    end
     assert_equal expected, actual
   end
 
@@ -395,9 +399,15 @@ class ReflectionTest < ActiveRecord::TestCase
   end
 
   def test_through_reflection_scope_chain_does_not_modify_other_reflections
-    orig_conds = Post.reflect_on_association(:first_blue_tags_2).scope_chain.inspect
-    Author.reflect_on_association(:misc_post_first_blue_tags_2).scope_chain
-    assert_equal orig_conds, Post.reflect_on_association(:first_blue_tags_2).scope_chain.inspect
+    orig_conds = assert_deprecated do
+      Post.reflect_on_association(:first_blue_tags_2).scope_chain
+    end.inspect
+    assert_deprecated do
+      Author.reflect_on_association(:misc_post_first_blue_tags_2).scope_chain
+    end
+    assert_equal orig_conds, assert_deprecated {
+      Post.reflect_on_association(:first_blue_tags_2).scope_chain
+    }.inspect
   end
 
   def test_symbol_for_class_name
diff --git a/activerecord/test/cases/serialized_attribute_test.rb b/activerecord/test/cases/serialized_attribute_test.rb
index a469da0a5b..24b83691f6 100644
--- a/activerecord/test/cases/serialized_attribute_test.rb
+++ b/activerecord/test/cases/serialized_attribute_test.rb
@@ -240,6 +240,20 @@ class SerializedAttributeTest < ActiveRecord::TestCase
     assert_equal [], light.long_state
   end
 
+  def test_unexpected_serialized_type
+    Topic.serialize :content, Hash
+    topic = Topic.create!(content: { zomg: true })
+
+    Topic.serialize :content, Array
+
+    topic.reload
+    error = assert_raise(ActiveRecord::SerializationTypeMismatch) do
+      topic.content
+    end
+    expected = "Attribute `content` was supposed to be a Array, but was a Hash. -- {:zomg=>true}"
+    assert_equal expected, error.to_s
+  end
+
   def test_serialized_column_should_unserialize_after_update_column
     t = Topic.create(content: "first")
     assert_equal("first", t.content)