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{"@context":"https://schema.org","@type":"DiscussionForumPosting","headline":"Variables are coerced twice during an execution when a field validation instrumentation is active","articleBody":"**Describe the bug**\r\nIt looks like variables are coerced twice during an execution using graphql-java 16.2, once in `execute` and once in `validateFieldsAndArguments`. This breaks e.g. enums with non-default names.\r\n\r\nVariables are first coerced [here](https://github.com/graphql-java/graphql-java/blob/master/src/main/java/graphql/execution/Execution.java#L69), then [added to the execution context](https://github.com/graphql-java/graphql-java/blob/master/src/main/java/graphql/execution/Execution.java#L90).\r\nIn `FieldValidationSupport`, the `QueryTraverser` is [initialized with those variables from the execution context](https://github.com/graphql-java/graphql-java/blob/master/src/main/java/graphql/execution/instrumentation/fieldvalidation/FieldValidationSupport.java#L36) and coerces them again [here](https://github.com/graphql-java/graphql-java/blob/master/src/main/java/graphql/analysis/QueryTraverser.java#L60).\r\n\r\n**To Reproduce**\r\nIf you have an enum value defined like this\r\n```kotlin\r\nGraphQLEnumType.newEnum()\r\n    .name(\"MyEnum\")\r\n    .description(\"My enum with all lowercase names.\")\r\n    .values(\r\n        MyEnum.values().map {\r\n            GraphQLEnumValueDefinition.newEnumValueDefinition()\r\n                .name(it.getLowerCaseName())\r\n                .value(it)\r\n                .build()\r\n        }\r\n    ).build()\r\n```\r\nthe first coercion works correctly, but the second one fails.","author":{"url":"https://github.com/jenssuhr","@type":"Person","name":"jenssuhr"},"datePublished":"2021-07-14T12:19:23.000Z","interactionStatistic":{"@type":"InteractionCounter","interactionType":"https://schema.org/CommentAction","userInteractionCount":3},"url":"https://github.com/2458/graphql-java/issues/2458"}