Additional changes ported back from master to allow faraday 1.x and 2.x

lib/oauth2/client.rb

@@ -59,15 +59,12 @@ def site=(value)
 
     # The Faraday connection object
     def connection
-      @connection ||= begin
-        conn = Faraday.new(site, options[:connection_opts])
-        if options[:connection_build]
-          conn.build do |b|
-            options[:connection_build].call(b)
+      @connection ||=
+        Faraday.new(site, options[:connection_opts]) do |builder|
+          if options[:connection_build]
+            options[:connection_build].call(builder)
           end
         end
-        conn
-      end
     end
 
     # The authorize endpoint URL of the OAuth2 provider

spec/oauth2/client_spec.rb

@@ -46,7 +46,7 @@
     it 'is able to pass a block to configure the connection' do
       connection = double('connection')
       builder = double('builder')
-      allow(connection).to receive(:build).and_yield(builder)
+      allow(Faraday).to receive(:new).and_yield(builder)
       allow(Faraday::Connection).to receive(:new).and_return(connection)
 
       expect(builder).to receive(:adapter).with(:test)