1 files changed, 28 insertions, 0 deletions
diff --git a/spec/ruby/core/io/buffer/readonly_spec.rb b/spec/ruby/core/io/buffer/readonly_spec.rb
new file mode 100644
index 0000000000..4eefc9f29f
--- /dev/null
+++ b/spec/ruby/core/io/buffer/readonly_spec.rb
@@ -0,0 +1,28 @@
+require_relative '../../../spec_helper'
+
+describe "IO::Buffer#readonly?" do
+  after :each do
+    @buffer&.free
+    @buffer = nil
+  end
+
+  it "is true for a buffer created with READONLY flag" do
+    @buffer = IO::Buffer.new(12, IO::Buffer::INTERNAL | IO::Buffer::READONLY)
+    @buffer.readonly?.should == true
+  end
+
+  it "is true for a buffer that is non-writable" do
+    @buffer = IO::Buffer.for("string")
+    @buffer.readonly?.should == true
+  end
+
+  it "is false for a modifiable buffer" do
+    @buffer = IO::Buffer.new(12)
+    @buffer.readonly?.should == false
+  end
+
+  it "is false for a null buffer" do
+    @buffer = IO::Buffer.new(0)
+    @buffer.readonly?.should == false
+  end
+end