Handle :log_if in Proxy constructors

lib/dry/logger/backends/proxy.rb

@@ -35,6 +35,14 @@ class Proxy < SimpleDelegator
           end
         end
 
+        # @since 1.0.2
+        # @api private
+        def initialize(backend, **options)
+          super(backend)
+          @options = options
+          self.log_if = @options[:log_if]
+        end
+
         # @since 1.0.0
         # @api private
         def log?(entry)

lib/dry/logger/dispatcher.rb

@@ -260,7 +260,7 @@ def add_backend(instance = nil, **backend_options)
         backend =
           case (instance ||= Dry::Logger.new(**options, **backend_options))
           when Backends::Stream then instance
-          else Backends::Proxy.new(instance)
+          else Backends::Proxy.new(instance, **options, **backend_options)
           end
 
         yield(backend) if block_given?

spec/dry/logger/backends/proxy_spec.rb

@@ -87,15 +87,21 @@ def error(exception, **payload)
 
   it "supports shortcut log_if" do
     backend = test_backend do
+      def info(message)
+        @stream.write(message)
+      end
+
       def error(message)
         @stream.write(message)
       end
     end
 
     logger = Dry.Logger(:test) { |s| s.add_backend(backend, log_if: :error?) }
 
-    logger.error("Hello World")
+    logger.info("Hello World")
+    logger.error("Oops")
 
-    expect(output).to eql("Hello World")
+    expect(stream).to_not include("Hello World")
+    expect(stream).to include("Oops")
   end
 end