Check that master key is returned when querying device for first time (#1166)

See matrix-org/synapse#11234

Author: erikjohnston

tests/41end-to-end-keys/08-cross-signing.pl

@@ -652,6 +652,21 @@
          matrix_join_room( $user2, $room_id );
       })->then( sub {
          sync_until_user_in_device_list( $user1, $user2 );
+      })->then( sub {
+         matrix_get_e2e_keys( $user1, $user2_id );
+      })->then( sub {
+         my ( $content ) = @_;
+
+         log_if_fail "key query content1", $content;
+
+         # Check that we do in fact see the master key when querying the
+         # devices.
+         assert_json_keys( $content->{master_keys}, $user2_id );
+         assert_json_keys( $content->{master_keys}->{$user2_id}, "keys");
+         assert_json_keys( $content->{master_keys}->{$user2_id}{keys},
+            "ed25519:nqOvzeuGWT/sRx3h7+MHoInYj3Uk2LD/unI9kDYcHwk");
+
+         matrix_sync_again( $user1 )
       })->then( sub {
          sign_json(
             $device, secret_key => $self_signing_secret_key,
@@ -671,8 +686,9 @@
       })->then( sub {
          my ( $content ) = @_;
 
-         log_if_fail "key query content", $content;
+         log_if_fail "key query content2", $content;
 
+         # Check that fetching the devices again returns the new signature
          assert_json_keys( $content->{device_keys}->{$user2_id}->{$user2_device}, "signatures" );
 
          assert_deeply_eq( $content->{device_keys}->{$user2_id}->{$user2_device}->{signatures}, {
@@ -681,6 +697,12 @@
             },
          } );
 
+         # Check that we still see the master key when querying the devices.
+         assert_json_keys( $content->{master_keys}, $user2_id );
+         assert_json_keys( $content->{master_keys}->{$user2_id}, "keys");
+         assert_json_keys( $content->{master_keys}->{$user2_id}{keys},
+            "ed25519:nqOvzeuGWT/sRx3h7+MHoInYj3Uk2LD/unI9kDYcHwk");
+
          Future->done(1);
       });
    };