1 files changed, 29 insertions, 0 deletions
diff --git a/src/ruby/spec/channel_credentials_spec.rb b/src/ruby/spec/channel_credentials_spec.rb
index b2bdf7032e..ecab5dca12 100644
--- a/src/ruby/spec/channel_credentials_spec.rb
+++ b/src/ruby/spec/channel_credentials_spec.rb
@@ -31,6 +31,7 @@ require 'grpc'
 
 describe GRPC::Core::ChannelCredentials do
   ChannelCredentials = GRPC::Core::ChannelCredentials
+  CallCredentials = GRPC::Core::CallCredentials
 
   def load_test_certs
     test_root = File.join(File.dirname(__FILE__), 'testdata')
@@ -60,4 +61,32 @@ describe GRPC::Core::ChannelCredentials do
       expect(&blk).to raise_error
     end
   end
+
+  describe '#compose' do
+    it 'can compose with a CallCredentials' do
+      certs = load_test_certs
+      channel_creds = ChannelCredentials.new(*certs)
+      auth_proc = proc { { 'plugin_key' => 'plugin_value' } }
+      call_creds = CallCredentials.new auth_proc
+      expect { channel_creds.compose call_creds }.not_to raise_error
+    end
+
+    it 'can compose with multiple CallCredentials' do
+      certs = load_test_certs
+      channel_creds = ChannelCredentials.new(*certs)
+      auth_proc = proc { { 'plugin_key' => 'plugin_value' } }
+      call_creds1 = CallCredentials.new auth_proc
+      call_creds2 = CallCredentials.new auth_proc
+      expect do
+        channel_creds.compose(call_creds1, call_creds2)
+      end.not_to raise_error
+    end
+
+    it 'cannot compose with ChannelCredentials' do
+      certs = load_test_certs
+      channel_creds1 = ChannelCredentials.new(*certs)
+      channel_creds2 = ChannelCredentials.new(*certs)
+      expect { channel_creds1.compose channel_creds2 }.to raise_error(TypeError)
+    end
+  end
 end