1 files changed, 66 insertions, 0 deletions
diff --git a/activerecord/test/cases/coders/yaml_column_test.rb b/activerecord/test/cases/coders/yaml_column_test.rb
new file mode 100644
index 0000000000..4a5559c62f
--- /dev/null
+++ b/activerecord/test/cases/coders/yaml_column_test.rb
@@ -0,0 +1,66 @@
+# frozen_string_literal: true
+
+require "cases/helper"
+
+module ActiveRecord
+  module Coders
+    class YAMLColumnTest < ActiveRecord::TestCase
+      def test_initialize_takes_class
+        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("tags", Array)
+        error = assert_raises(SerializationTypeMismatch) do
+          coder.dump("a")
+        end
+        assert_equal %{can't dump `tags`: 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("tags", Array)
+        error = assert_raises(SerializationTypeMismatch) do
+          coder.load "--- foo"
+        end
+        assert_equal %{can't load `tags`: was supposed to be a Array, but was a String. -- "foo"}, error.to_s
+      end
+
+      def test_nil_is_ok
+        coder = YAMLColumn.new("attr_name")
+        assert_nil coder.load "--- "
+      end
+
+      def test_returns_new_with_different_class
+        coder = YAMLColumn.new("attr_name", SerializationTypeMismatch)
+        assert_equal SerializationTypeMismatch, coder.load("--- ").class
+      end
+
+      def test_returns_string_unless_starts_with_dash
+        coder = YAMLColumn.new("attr_name")
+        assert_equal "foo", coder.load("foo")
+      end
+
+      def test_load_handles_other_classes
+        coder = YAMLColumn.new("attr_name")
+        assert_equal [], coder.load([])
+      end
+
+      def test_load_doesnt_swallow_yaml_exceptions
+        coder = YAMLColumn.new("attr_name")
+        bad_yaml = "--- {"
+        assert_raises(Psych::SyntaxError) do
+          coder.load(bad_yaml)
+        end
+      end
+
+      def test_load_doesnt_handle_undefined_class_or_module
+        coder = YAMLColumn.new("attr_name")
+        missing_class_yaml = '--- !ruby/object:DoesNotExistAndShouldntEver {}\n'
+        assert_raises(ArgumentError) do
+          coder.load(missing_class_yaml)
+        end
+      end
+    end
+  end
+end