add Faraday::Connection#dup

lib/faraday/builder.rb

@@ -20,12 +20,12 @@ module Faraday
       Builder.new(&block).tap { |builder| builder.run(inner) }
     end
 
-    def initialize
-      @handlers = []
-      yield self
+    def initialize(handlers = [])
+      @handlers = handlers
+      yield self if block_given?
     end
 
-    def run app
+    def run(app)
       @handlers.unshift app
     end
 
@@ -53,5 +53,13 @@ module Faraday
     def use_symbol(mod, key, *args, &block)
       use mod.lookup_module(key), *args, &block
     end
+
+    def ==(other)
+      other.is_a?(self.class) && @handlers == other.handlers
+    end
+
+    def dup
+      self.class.new @handlers.dup
+    end
   end
 end

lib/faraday/connection.rb

@@ -34,6 +34,8 @@ module Faraday
       merge_headers @headers, options[:headers] if options[:headers]
       if block
         @builder = Builder.create_with_inner_app(&block)
+      else
+        @builder = options[:builder] || Builder.new
       end
     end
 
@@ -141,6 +143,10 @@ module Faraday
       uri
     end
 
+    def dup
+      self.class.new(build_url(''), :headers => headers.dup, :params => params.dup, :builder => builder.dup)
+    end
+
     def replace_query(uri, params)
       url_params = @params.dup
       if uri.query && !uri.query.empty?

test/connection_test.rb

@@ -158,4 +158,19 @@ class TestConnection < Faraday::TestCase
     end
     assert_equal "a%5Bb%5D=1%20%2B%202", conn.build_query('a[b]' => '1 + 2')
   end
+
+  def test_dups_connection_object
+    conn = Faraday::Connection.new 'http://sushi.com/foo' do |b|
+      b.adapter :net_http
+    end
+    conn.headers['content-type'] = 'text/plain'
+    conn.params['a'] = '1'
+
+    duped = conn.dup
+    assert_equal conn.build_url(''), duped.build_url('')
+    [:headers, :params, :builder].each do |attr|
+      assert_equal     conn.send(attr),           duped.send(attr)
+      assert_not_equal conn.send(attr).object_id, duped.send(attr).object_id
+    end
+  end
 end