--- a/test/transport/kex/test_diffie_hellman_group_exchange_sha256.rb
+++ b/test/transport/kex/test_diffie_hellman_group_exchange_sha256.rb
@@ -1,5 +1,6 @@
 require 'common'
 require 'net/ssh/transport/kex/diffie_hellman_group_exchange_sha1'
+require 'transport/kex/test_diffie_hellman_group_exchange_sha1'
 
 module Transport; module Kex
 
--- a/test/transport/kex/test_ecdh_sha2_nistp384.rb
+++ b/test/transport/kex/test_ecdh_sha2_nistp384.rb
@@ -1,4 +1,5 @@
 require 'openssl'
+require 'transport/kex/test_ecdh_sha2_nistp256'
 
 unless defined?(OpenSSL::PKey::EC)
   puts "Skipping tests for ecdh-sha2-nistp384 key exchange"
--- a/test/transport/kex/test_ecdh_sha2_nistp521.rb
+++ b/test/transport/kex/test_ecdh_sha2_nistp521.rb
@@ -1,4 +1,5 @@
 require 'openssl'
+require 'transport/kex/test_ecdh_sha2_nistp256'
 
 unless defined?(OpenSSL::PKey::EC)
   puts "Skipping tests for ecdh-sha2-nistp521 key exchange"