Fix drizzleField to prevent unnecessary ModelLoader queries in mutations

[Copilot]

drizzleField within mutations caused unnecessary re-queries via ModelLoader even when resolvers returned complete data. This was particularly problematic for delete operations attempting to fetch already-deleted records.

Root Cause

queryFromInfo sets loader mappings that prevent ModelLoader from re-querying. It was only called when resolvers explicitly invoked the query parameter. Mutations using .returning() don't need the query function since they return data directly:

deleteCategory: t.drizzleField({
  type: ['categories'],
  resolve: async (query, _root, args) => {
    // query() never called - mappings never set
    return db.delete(categories)
      .where(eq(categories.name, args.name))
      .returning();
  },
});

This resulted in:

1. DELETE with RETURNING executed
2. ModelLoader re-queries for the deleted record (fails)

Changes

Modified drizzleField and drizzleFieldWithInput to:

• Track if query function is called via flag
• Await resolver completion to handle async properly
• Call queryFromInfo after resolver if query function was not invoked

This ensures mappings are set regardless of whether the resolver uses the query function, while avoiding duplicate calls when it does.

Test Coverage

Added mutation-field-mapping.test.ts validating:

• Delete mutations: 1 query instead of 2
• Create mutations: 1 query instead of 2
• Existing query-based mutations: unchanged behavior

Warning

Firewall rules blocked me from connecting to one or more addresses (expand for details)

I tried to connect to the following addresses, but was blocked by firewall rules:

• checkpoint.prisma.io
  • Triggering command: /usr/local/bin/node /usr/local/bin/node /home/REDACTED/work/pothos/pothos/node_modules/.pnpm/prisma@7.1.0_@types+react@19.2.7_better-sqlite3@12.5.0_react-dom@19.2.3_react@19.2.3__react@19.2.3_typescript@5.9.3/node_modules/prisma/build/child {"product":"prisma","version":"7.1.0","cli_install_type":"local","information":"","local_timestamp":"2025-12-21T09:26:13Z","project_hash":"344f9b9a","cli_path":"/home/REDACTED/work/pothos/pothos/packages/plugin-prisma/node_modules/prisma/build/index.js","cl sh .1/b�� swc src -d lib --config-file ../../.swcrc -C module.type=commonjs --strip-leading-paths node federation/node_modules/.bin/node s --strip-leadinnode node n/node node .1/b�� son node -r @swc-node/register ../../scripts/esm--config-file -d tools/pnpm/10.15.1_tmp_3499/node_modules/pnpm/dist/node-gyp-bin/node --config-file ../../.swcrc -C node (dns block)
  • Triggering command: /usr/local/bin/node /usr/local/bin/node /home/REDACTED/work/pothos/pothos/node_modules/.pnpm/prisma@7.1.0_@types+react@19.2.7_better-sqlite3@12.5.0_react-dom@19.2.3_react@19.2.3__react@19.2.3_typescript@5.9.3/node_modules/prisma/build/child {"product":"prisma","version":"7.1.0","cli_install_type":"local","information":"","local_timestamp":"2025-12-21T09:26:15Z","project_hash":"33bcc4ae","cli_path":"/home/REDACTED/work/pothos/pothos/packages/plugin-prisma/node_modules/prisma/build/index.js","cl node k/po�� -node/register ../../scripts/esm-transformer.ts sh _modules/pnpm/dist/node-gyp-bin/node s --strip-leadinsh sh node node .1/b�� && swc src -d esm --config-file ../../.swcrc -C module.type=es6--config-file node errors/node_modules/.bin/sh sm:extensions sh node sh (dns block)
  • Triggering command: /usr/local/bin/node /usr/local/bin/node /home/REDACTED/work/pothos/pothos/node_modules/.pnpm/prisma@7.1.0_@types+react@19.2.7_better-sqlite3@12.5.0_react-dom@19.2.3_react@19.2.3__react@19.2.3_typescript@5.9.3/node_modules/prisma/build/child {"product":"prisma","version":"7.1.0","cli_install_type":"local","information":"","local_timestamp":"2025-12-21T09:26:25Z","project_hash":"5d274ca5","cli_path":"/home/REDACTED/work/pothos/pothos/packages/plugin-with-input/node_modules/prisma/build/index.js" sh .1/b�� son node -r @swc-node/register ../../scripts/esm-transformer.ts sh _modules/pnpm/dist/node-gyp-bin/node sm:extensions node node node .1/b�� build:esm node les/.bin/sh ../.swcrc -C modsh build /home/REDACTED/.coTS_NODE_PROJECT=../../tsconfig.json node -r @swc-node/register ../../scripts/esm-transformer.ts sh (dns block)

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Original prompt

---

This section details on the original issue you should resolve

<issue_title>[@pothos/plugin-drizzle] Failed to map the Mutation field, causing an unnecessary ModelLoader to run.</issue_title>
<issue_description>The drizzleField within Mutation returns an empty object for state.mappings in stateFromInfo.
Therefore, even if sufficient values are returned during resolution when executing the Mutation, it always performs a re-query.
As a result, the delete operation attempts to retrieve a non-existent record, preventing the return of valid values.

• Verification Repository (plugin-test Brunch)

https://github.com/SoraKumo001/pothos-drizzle-generator-sample/tree/plugin-test

• code

https://github.com/SoraKumo001/pothos-drizzle-generator-sample/blob/4cfc3749d20c8e968d13bbb7da835bbdd239ba07/src/pothos-drizzle-generator/PothosDrizzleGenerator.ts#L555-L603

• GraphQL

mutation Test {
  createOneCategory(input: { name: "test" }) {
    id
  }
  deleteCategory(where: { name: { eq: "test" } }) {
    id
  }
}

• SQL

===========================
 insert into
  "Category" ("id", "name", "createdAt", "updatedAt")
values
  (default, $1, default, default)
returning
  "id",
  "name",
  "createdAt",
  "updatedAt"
--
 [ 'test' ]
===========================
 select
  "d0"."id" as "id"
from
  "Category" as "d0"
where
  "d0"."id" in ($1)
--
 [ 'bf26c514-65de-4950-bb75-c996bdcde0b2' ]
set Map(0) {}
===========================
 delete from "Category"
where
  "Category"."name" = $1
returning
  "id",
  "name",
  "createdAt",
  "updatedAt"
--
 [ 'test' ]
===========================
 select
  "d0"."id" as "id"
from
  "Category" as "d0"
where
  "d0"."id" in ($1)
--
 [ 'bf26c514-65de-4950-bb75-c996bdcde0b2' ]

• Error message

{
  "errors": [
    {
      "message": "Model categories(bf26c514-65de-4950-bb75-c996bdcde0b2) not found",
      "locations": [
        {
          "line": 6,
          "column": 5
        }
      ],
      "path": [
        "deleteCategory",
        0,
        "id"
      ]
    }
  ]
}

</issue_description>

<agent_instructions>Create a simple failing test, then implement a fix</agent_instructions>

Comments on the Issue (you are @copilot in this section)

• Fixes [@pothos/plugin-drizzle] Failed to map the Mutation field, causing an unnecessary ModelLoader to run. #1582

---

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Project	Deployment	Review	Updated (UTC)
pothos	Ready	Preview, Comment	Dec 21, 2025 9:43am