Try to fix preview server config

middleman-core/lib/middleman-core/application.rb

@@ -271,6 +271,8 @@ module Middleman
       # Before config is parsed, before extensions get to it.
       execute_callbacks(:initialized)
 
+      apply_cli_options
+
       # Before config is parsed. Mostly used for extensions.
       execute_callbacks(:before_configuration)
 
@@ -283,14 +285,7 @@ module Middleman
       # Run any `configure` blocks for the current mode.
       execute_callbacks([:configure, config[:mode]])
 
-      config[:cli_options].each do |k, v|
-        setting = config.setting(k.to_sym)
-        next unless setting
-
-        v = setting.options[:import].call(v) if setting.options[:import]
-
-        config[k.to_sym] = v
-      end
+      apply_cli_options
 
       # Post parsing, pre-extension callback
       execute_callbacks(:after_configuration_eval)
@@ -308,6 +303,17 @@ module Middleman
       execute_callbacks(:ready) unless config[:exit_before_ready]
     end
 
+    def apply_cli_options
+      config[:cli_options].each do |k, v|
+        setting = config.setting(k.to_sym)
+        next unless setting
+
+        v = setting.options[:import].call(v) if setting.options[:import]
+
+        config[k.to_sym] = v
+      end
+    end
+
     # Eval config
     def evaluate_configuration!
       # Check for and evaluate local configuration in `config.rb`

middleman-core/lib/middleman-core/preview_server.rb

@@ -172,18 +172,23 @@ module Middleman
         end
 
         # store configured port to make a check later on possible
-        configured_port = app.config[:port]
+        configured_port = possible_from_cli(:port, app.config)
 
         # Use configuration values to set `bind_address` etc. in
         # `server_information`
-        server_information.use app.config
+        server_information.use({
+          bind_address: possible_from_cli(:bind_address, app.config),
+          port: possible_from_cli(:port, app.config),
+          server_name: possible_from_cli(:server_name, app.config),
+          https: possible_from_cli(:https, app.config)
+        })
 
-        app.logger.warn format('== The Middleman uses a different port "%s" then the configured one "%s" because some other server is listening on that port.', server_information.port, configured_port) unless app.config[:port] == configured_port
+        app.logger.warn format('== The Middleman uses a different port "%s" then the configured one "%s" because some other server is listening on that port.', server_information.port, configured_port) unless server_information.port == configured_port
 
-        @environment = app.config[:environment]
+        @environment = possible_from_cli(:environment, app.config)
 
-        @ssl_certificate = app.config[:ssl_certificate]
-        @ssl_private_key = app.config[:ssl_private_key]
+        @ssl_certificate = possible_from_cli(:ssl_certificate, app.config)
+        @ssl_private_key = possible_from_cli(:ssl_private_key, app.config)
 
         app.files.on_change :reload do
           $mm_reload = true
@@ -199,6 +204,14 @@ module Middleman
         app
       end
 
+      def possible_from_cli(key, config)
+        if @cli_options[key] && @cli_options[key] != :undefined
+          @cli_options[key]
+        else
+          config[key]
+        end
+      end
+
       # Trap some interupt signals and shut down smoothly
       # @return [void]
       def register_signal_handlers