spec/device/stdout_spec.rb in logstash-logger-0.6.2 vs spec/device/stdout_spec.rb in logstash-logger-0.7.0

@@ -1,14 +1,31 @@
 require 'logstash-logger'
 
 describe LogStashLogger::Device::Stdout do
+  let(:stdout) { $stdout }
+
   it "writes to $stdout" do
-    expect(subject.to_io).to eq($stdout)
-    expect($stdout).to receive(:write).once
+    expect(subject.to_io).to eq(stdout)
+    expect(stdout).to receive(:write).once
     subject.write("test")
   end
 
   it "ignores #close" do
-    expect($stdout).not_to receive(:close)
+    expect(stdout).not_to receive(:close)
     subject.close
+  end
+
+  context "when the default $stdout has been overridden" do
+    before { $stdout = StringIO.new }
+    after  { $stdout = STDOUT }
+
+    let(:injected_stdout) { STDOUT }
+
+    subject { described_class.new(io: injected_stdout) }
+
+    it "accepts an injectable reference to stdout" do
+      expect(subject.to_io).to eq(injected_stdout)
+      expect(injected_stdout).to receive(:write).once
+      subject.write("test")
+    end
   end
 end