1 files changed, 48 insertions, 0 deletions
diff --git a/spec/ruby/core/string/shared/replace.rb b/spec/ruby/core/string/shared/replace.rb
new file mode 100644
index 0000000000..24dac0eb27
--- /dev/null
+++ b/spec/ruby/core/string/shared/replace.rb
@@ -0,0 +1,48 @@
+# frozen_string_literal: false
+describe :string_replace, shared: true do
+  it "returns self" do
+    a = "a"
+    a.send(@method, "b").should equal(a)
+  end
+
+  it "replaces the content of self with other" do
+    a = "some string"
+    a.send(@method, "another string")
+    a.should == "another string"
+  end
+
+  it "replaces the encoding of self with that of other" do
+    a = "".encode("UTF-16LE")
+    b = "".encode("UTF-8")
+    a.send(@method, b)
+    a.encoding.should == Encoding::UTF_8
+  end
+
+  it "carries over the encoding invalidity" do
+    a = "\u{8765}".force_encoding('ascii')
+    "".send(@method, a).valid_encoding?.should be_false
+  end
+
+  it "tries to convert other to string using to_str" do
+    other = mock('x')
+    other.should_receive(:to_str).and_return("converted to a string")
+    "hello".send(@method, other).should == "converted to a string"
+  end
+
+  it "raises a TypeError if other can't be converted to string" do
+    -> { "hello".send(@method, 123)       }.should raise_error(TypeError)
+    -> { "hello".send(@method, [])        }.should raise_error(TypeError)
+    -> { "hello".send(@method, mock('x')) }.should raise_error(TypeError)
+  end
+
+  it "raises a FrozenError on a frozen instance that is modified" do
+    a = "hello".freeze
+    -> { a.send(@method, "world") }.should raise_error(FrozenError)
+  end
+
+  # see [ruby-core:23666]
+  it "raises a FrozenError on a frozen instance when self-replacing" do
+    a = "hello".freeze
+    -> { a.send(@method, a) }.should raise_error(FrozenError)
+  end
+end