{"action":"created","issue":{"url":"https://api.github.com/repos/facebook/relay/issues/667","labels_url":"https://api.github.com/repos/facebook/relay/issues/667/labels{/name}","comments_url":"https://api.github.com/repos/facebook/relay/issues/667/comments","events_url":"https://api.github.com/repos/facebook/relay/issues/667/events","html_url":"https://github.com/facebook/relay/issues/667","id":121285451,"number":667,"title":"Validation error of type FieldsConflict","user":{"login":"stephanos","id":159852,"avatar_url":"https://avatars.githubusercontent.com/u/159852?v=3","gravatar_id":"","url":"https://api.github.com/users/stephanos","html_url":"https://github.com/stephanos","followers_url":"https://api.github.com/users/stephanos/followers","following_url":"https://api.github.com/users/stephanos/following{/other_user}","gists_url":"https://api.github.com/users/stephanos/gists{/gist_id}","starred_url":"https://api.github.com/users/stephanos/starred{/owner}{/repo}","subscriptions_url":"https://api.github.com/users/stephanos/subscriptions","organizations_url":"https://api.github.com/users/stephanos/orgs","repos_url":"https://api.github.com/users/stephanos/repos","events_url":"https://api.github.com/users/stephanos/events{/privacy}","received_events_url":"https://api.github.com/users/stephanos/received_events","type":"User","site_admin":false},"labels":[],"state":"closed","locked":false,"assignee":null,"milestone":null,"comments":4,"created_at":"2015-12-09T16:29:52Z","updated_at":"2015-12-10T09:49:04Z","closed_at":"2015-12-10T09:49:04Z","body":"We are currently stuck with this Relay error: `Validation error of type FieldsConflict: cycle: they return differing types TypeA and TypeB`.\r\n\r\nBasically this is the query that we attempt:\r\n\r\n```\r\nThings {\r\n  ... on TVShow {\r\n     owner {\r\n        name\r\n     }\r\n  },\r\n  ... on Pet {\r\n     owner {\r\n        name\r\n     }\r\n  }\r\n}\r\n```\r\n\r\n`owner` of a Pet is of type `Human`, `owner` of a `TVShow` is of type `Business`. Relay doesn't seem to like that.\r\n\r\nOn the GraphQL issue tracker there was a discussion about a very similar issue over a month ago. It was said that a workaround would be to use an alias. But this doesn't work for us in Relay (yet in Graphiql the error actually disappears!).\r\n\r\nEventually, the issue was closed and the behavior was changed to allow 'conflicts' like this: \"[...] two fields which could not overlap are still treated as a potential conflict. This change loosens this rule, allowing fields which can never both apply in a frame of execution to diverge.\"\r\n\r\nAm I missing something or is Relay being too strict here?"},"comment":{"url":"https://api.github.com/repos/facebook/relay/issues/comments/163558842","html_url":"https://github.com/facebook/relay/issues/667#issuecomment-163558842","issue_url":"https://api.github.com/repos/facebook/relay/issues/667","id":163558842,"user":{"login":"stephanos","id":159852,"avatar_url":"https://avatars.githubusercontent.com/u/159852?v=3","gravatar_id":"","url":"https://api.github.com/users/stephanos","html_url":"https://github.com/stephanos","followers_url":"https://api.github.com/users/stephanos/followers","following_url":"https://api.github.com/users/stephanos/following{/other_user}","gists_url":"https://api.github.com/users/stephanos/gists{/gist_id}","starred_url":"https://api.github.com/users/stephanos/starred{/owner}{/repo}","subscriptions_url":"https://api.github.com/users/stephanos/subscriptions","organizations_url":"https://api.github.com/users/stephanos/orgs","repos_url":"https://api.github.com/users/stephanos/repos","events_url":"https://api.github.com/users/stephanos/events{/privacy}","received_events_url":"https://api.github.com/users/stephanos/received_events","type":"User","site_admin":false},"created_at":"2015-12-10T09:49:04Z","updated_at":"2015-12-10T09:49:04Z","body":"We investigated this further. We didn't realize that the error was reported by our backend (Java implementation). Sorry for the false alarm :("}}