1 files changed, 28 insertions, 0 deletions
diff --git a/spec/ruby/core/string/concat_spec.rb b/spec/ruby/core/string/concat_spec.rb
new file mode 100644
index 0000000000..939be5ed0a
--- /dev/null
+++ b/spec/ruby/core/string/concat_spec.rb
@@ -0,0 +1,28 @@
+require File.expand_path('../../../spec_helper', __FILE__)
+require File.expand_path('../fixtures/classes', __FILE__)
+require File.expand_path('../shared/concat', __FILE__)
+
+describe "String#concat" do
+  it_behaves_like :string_concat, :concat
+  it_behaves_like :string_concat_encoding, :concat
+
+  ruby_version_is "2.4" do
+    it "takes multiple arguments" do
+      str = "hello "
+      str.concat "wo", "", "rld"
+      str.should == "hello world"
+    end
+
+    it "concatenates the initial value when given arguments contain 2 self" do
+      str = "hello"
+      str.concat str, str
+      str.should == "hellohellohello"
+    end
+
+    it "returns self when given no arguments" do
+      str = "hello"
+      str.concat.should equal(str)
+      str.should == "hello"
+    end
+  end
+end