✨ Add greeting code data to responses

This simplifies caching of the server capabilities, as many servers will
send their capabilities inside the greeting.  Needed for #31.

Author: nevans

lib/net/imap.rb

@@ -2128,7 +2128,7 @@ def initialize(host, port_or_options = {},
         else
           @usessl = false
         end
-        @responses = Hash.new([].freeze)
+        @responses = Hash.new {|h, k| h[k] = [] }
         @tagged_responses = {}
         @response_handlers = []
         @tagged_response_arrival = new_cond
@@ -2144,6 +2144,7 @@ def initialize(host, port_or_options = {},
         if @greeting.nil?
           raise Error, "connection closed"
         end
+        record_untagged_response_code(@greeting)
         if @greeting.name == "BYE"
           raise ByeResponseError, @greeting
         end
@@ -2208,10 +2209,7 @@ def receive_responses
               end
             when UntaggedResponse
               record_response(resp.name, resp.data)
-              if resp.data.instance_of?(ResponseText) &&
-                  (code = resp.data.code)
-                record_response(code.name, code.data)
-              end
+              record_untagged_response_code(resp)
               if resp.name == "BYE" && @logout_command_tag.nil?
                 @sock.close
                 @exception = ByeResponseError.new(resp)
@@ -2289,6 +2287,13 @@ def get_response
       return @parser.parse(buff)
     end
 
+    def record_untagged_response_code(resp)
+      if resp.data.instance_of?(ResponseText) &&
+          (code = resp.data.code)
+        record_response(code.name, code.data)
+      end
+    end
+
     def record_response(name, data)
       unless @responses.has_key?(name)
         @responses[name] = []

test/net/imap/test_imap.rb

@@ -928,7 +928,12 @@ def test_responses
     end
     begin
       imap = Net::IMAP.new(server_addr, port: port)
+      # responses available before SELECT/EXAMINE
+      assert_equal(%w[IMAP4REV1 AUTH=PLAIN STARTTLS],
+                   imap.responses("CAPABILITY", &:last))
       resp = imap.select "INBOX"
+      # responses are cleared after SELECT/EXAMINE
+      assert_equal(nil, imap.responses("CAPABILITY", &:last))
       assert_equal([Net::IMAP::TaggedResponse, "RUBY0001", "OK"],
                    [resp.class, resp.tag, resp.name])
       assert_equal([172], imap.responses { _1["EXISTS"] })