Handle last_stream_member more gently in CLI

Author: acogoluegnes

deps/rabbitmq_cli/lib/rabbitmq/cli/streams/commands/delete_replica_command.ex

@@ -29,6 +29,8 @@ defmodule RabbitMQ.CLI.Streams.Commands.DeleteReplicaCommand do
       {:error, :quorum_queue_not_supported} ->
         {:error, "Cannot delete replicas from a quorum queue"}
 
+      {:error, :last_stream_member} ->
+        {:error, "Cannot delete the last member of a stream"}
       other ->
         other
     end

deps/rabbitmq_cli/test/streams/delete_replica_command_test.exs

@@ -20,7 +20,8 @@ defmodule RabbitMQ.CLI.Streams.Commands.DeleteReplicaCommandTest do
   setup context do
     {:ok, opts: %{
         node: get_rabbit_hostname(),
-        timeout: context[:test_timeout] || 30000
+        timeout: context[:test_timeout] || 30000,
+        vhost: "/"
       }}
   end
 
@@ -42,6 +43,12 @@ defmodule RabbitMQ.CLI.Streams.Commands.DeleteReplicaCommandTest do
     assert @command.validate(["stream-queue-a", "rabbit@new-node"], %{}) == :ok
   end
 
+  test "run: trying to delete the last member of a stream should fail and return a meaningful message", context do
+    declare_stream("test_stream_1", "/")
+    assert @command.run(["test_stream_1", get_rabbit_hostname()], context[:opts]) ==
+             {:error, "Cannot delete the last member of a stream"}
+  end
+
   @tag test_timeout: 3000
   test "run: targeting an unreachable node throws a badrpc" do
     assert match?({:badrpc, _}, @command.run(["stream-queue-a", "rabbit@new-node"],

deps/rabbitmq_cli/test/test_helper.exs

@@ -162,6 +162,10 @@ defmodule TestHelper do
               [queue_name, durable, auto_delete, args, owner, "acting-user"])
   end
 
+  def declare_stream(name, vhost) do
+    declare_queue(name, vhost, true, false, [{"x-queue-type", :longstr, "stream"}])
+  end
+
   def delete_queue(name, vhost) do
     queue_name = :rabbit_misc.r(vhost, :queue, name)
     :rpc.call(get_rabbit_hostname(),