ReplaceFieldType.ts

const ReplaceFieldType: Plugin = (builder) => {
  // Process the output fields
  builder.hook("GraphQLObjectType:fields:field", (field, build, context) => {
    const { getTypeByName, graphql } = build;
    const { GraphQLList, GraphQLNonNull } = graphql;
    const {
      scope: { pgFieldIntrospection: attr },
    } = context;

    if (!attr || attr.kind !== "attribute") {
      return field;
    }

    const overrideType = attr.tags.overrideType;
    if (!overrideType || typeof overrideType !== "string") {
      return field;
    }

    const typeName = overrideType.replace("[]", "");
    const isArray = overrideType.includes("[]");
    const gqlType = getTypeByName(typeName);
    if (!gqlType) {
      return field;
    }

    return {
      ...field,
      type: isArray ? new GraphQLList(new GraphQLNonNull(gqlType)) : gqlType,
    };
  });

  // Process the input fields
  builder.hook(
    "GraphQLInputObjectType:fields:field",
    (field, build, context) => {
      const { getTypeByName, graphql } = build;
      const { GraphQLList, GraphQLNonNull } = graphql;

      const {
        scope: { pgFieldIntrospection: attr },
      } = context;

      if (!attr || attr.kind !== "attribute") {
        return field;
      }

      const overrideType = attr.tags.overrideType;
      if (!overrideType) {
        return field;
      }

      const typeName = overrideType.replace("[]", "");
      const isArray = overrideType.includes("[]");
      const gqlType = getTypeByName(typeName + "Input");
      if (!gqlType) {
        return field;
      }

      return {
        ...field,
        type: isArray ? new GraphQLList(new GraphQLNonNull(gqlType)) : gqlType,
      };
    }
  );
};