refactor: move lib/postal/smtp_server to app/lib/smtp_server

spec/lib/smtp_server/client/helo_spec.rb

@@ -0,0 +1,36 @@
+# frozen_string_literal: true
+
+require "rails_helper"
+
+module SMTPServer
+
+  describe Client do
+    let(:ip_address) { "1.2.3.4" }
+    subject(:client) { described_class.new(ip_address) }
+
+    describe "HELO" do
+      it "returns the hostname" do
+        expect(client.state).to eq :welcome
+        expect(client.handle("HELO: test.example.com")).to eq "250 #{Postal.config.dns.smtp_server_hostname}"
+        expect(client.state).to eq :welcomed
+      end
+    end
+
+    describe "EHLO" do
+      it "returns the capabilities" do
+        expect(client.handle("EHLO test.example.com")).to eq ["250-My capabilities are",
+                                                              "250 AUTH CRAM-MD5 PLAIN LOGIN"]
+      end
+
+      context "when TLS is enabled" do
+        it "returns capabilities include starttls" do
+          allow(Postal.config.smtp_server).to receive(:tls_enabled?).and_return(true)
+          expect(client.handle("EHLO test.example.com")).to eq ["250-My capabilities are",
+                                                                "250-STARTTLS",
+                                                                "250 AUTH CRAM-MD5 PLAIN LOGIN"]
+        end
+      end
+    end
+  end
+
+end