respect Faraday::RequestOptions#params_encoder

Fixes lostisland#269

lib/faraday/adapter/test.rb

@@ -144,10 +144,11 @@ def configure
       def call(env)
         super
         normalized_path = Faraday::Utils.normalize_path(env[:url])
+        params_encoder = env.request.params_encoder || Faraday::Utils.default_params_encoder
 
         if stub = stubs.match(env[:method], normalized_path, env.request_headers, env[:body])
           env[:params] = (query = env[:url].query) ?
-            Faraday::Utils.parse_nested_query(query)  :
+            params_encoder.decode(query)  :
             {}
           status, headers, body = stub.block.call(env)
           save_response(env, status, body, headers)

test/adapters/test_middleware_test.rb

@@ -69,6 +69,35 @@ def test_yields_env_to_stubs
       assert_equal 'a', @conn.get('http://foo.com/hello?a=1').body
     end
 
+    def test_parses_params_with_default_encoder
+      @stubs.get '/hello' do |env|
+        assert_equal '1', env[:params]['a']['b']
+        [200, {}, 'a']
+      end
+
+      assert_equal 'a', @conn.get('http://foo.com/hello?a[b]=1').body
+    end
+
+    def test_parses_params_with_nested_encoder
+      @stubs.get '/hello' do |env|
+        assert_equal '1', env[:params]['a']['b']
+        [200, {}, 'a']
+      end
+
+      @conn.options.params_encoder = Faraday::NestedParamsEncoder
+      assert_equal 'a', @conn.get('http://foo.com/hello?a[b]=1').body
+    end
+
+    def test_parses_params_with_flat_encoder
+      @stubs.get '/hello' do |env|
+        assert_equal '1', env[:params]['a[b]']
+        [200, {}, 'a']
+      end
+
+      @conn.options.params_encoder = Faraday::FlatParamsEncoder
+      assert_equal 'a', @conn.get('http://foo.com/hello?a[b]=1').body
+    end
+
     def test_raises_an_error_if_no_stub_is_found_for_request
       assert_raises Stubs::NotFound do
         @conn.get('/invalid'){ [200, {}, []] }