Improve specs coverage of Msf::RPC::RPC_Session

lib/msf/core/rpc/v10/rpc_session.rb

@@ -338,6 +338,8 @@ def rpc_interactive_write(sid, data)
       session.channels.each_value do |ch|
         interacting ||= ch.respond_to?('interacting') && ch.interacting
       end
+    else
+      interacting = session.interacting
     end
 
     if interacting
@@ -534,11 +536,6 @@ def rpc_compatible_modules( sid)
     smb
   ].freeze
 
-  SHELL_OPERATION_SESSIONS = %w[
-    shell
-    powershell
-  ]
-
   def _find_module(_mtype, mname)
     mod = framework.modules.create(mname)
     error(500, 'Invalid Module') if mod.nil?
@@ -552,16 +549,16 @@ def _valid_session(sid, operation_type)
 
     case operation_type
     when 'ring'
-      error(500, "Session #{s.type} does not support ring operations") unless s.respond_to?(:ring)
+      error(500, "Session of #{session.type} type does not support ring operations") unless session.respond_to?(:ring)
     when 'meterpreter'
-      error(500, 'Invalid session type') unless s.type == 'meterpreter'
+      error(500, 'Invalid session type') unless session.type == 'meterpreter'
     when 'interactive'
-      unless INTERACTIVE_OPERATION_SESSIONS.include?(s.type)
-        error(500, "Session doesn't support interactive operations")
+      unless INTERACTIVE_OPERATION_SESSIONS.include?(session.type)
+        error(500, "Session of #{session.type} type doesn't support interactive operations")
       end
     when 'shell'
-      unless SHELL_OPERATION_SESSIONS.include?(s.type)
-        error(500, "Session doesn't support command shell operations")
+      if INTERACTIVE_OPERATION_SESSIONS.include?(session.type)
+        error(500, "Use `interactive_read` and `interactive_write` for sessions of #{session.type} type")
       end
     else
       error(500, 'Invalid operation type')