This generalizes the "arguments of correct type" and "default values of correct type" to a single rule "values of correct type" which has been re-written to rely on a traversal rather than the utility function `isValidLiteralValue`. To reduce breaking scope, this does not remove that utility even though it's no longer used directly within the library. Since the default values rule included another validation rule that rule was renamed to a more apt "variable default value allowed".
This also includes the original errors from custom scalars in the validation error output, solving the remainder of graphql/graphql-js#821.
ref: graphql/graphql-js#1144
This includes:
graphql/graphql-js#1147graphql/graphql-js#355
This also fixes two bugs in the Schema
- types that were not found where still added to the typeMap
- InputObject args should not be searched for types.
This factors out the enum value validation from scalar value validation and ensures the same try/catch is used in isValidLiteralValue as isValidPHPValue and protecting from errors in valueFromAST.
ref: graphql/graphql-js#1126
