Describe the bug
The useMutationState hook doesn’t propagate generic type parameters (TData, TError, TVariables, TContext) into the select callback.
As a result, when filtering by a specific mutationKey, TypeScript doesn’t infer correct types for mutation.state, forcing developers to cast manually.
Your minimal, reproducible example
https://www.typescriptlang.org/play/?#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-FBMEYHu8EoWG2r1kKE6PlApp0FQb6Auk6bHrqPzDFhCQjFkCJInhRF-rM+HEdcpHgaRQk0VQdEwDuDFwcGzFIQhqETliICSGAQ7dsKJlmfYNCBhZWDjlceogH0shdHAGCRA5TnhJwAhpGgBIzok1okhOAD6nwFmaQ68vyUCCr2XHID5Bo3NAaUWEokQCHZWIwMshiSJorx5dSxC6ASGCKiqjbhAAxBACyKqowr+YFwWhQgRLhf8IimRgYCzuuiQVtQwrNRgqgCGaIoCAAFj8ThQAA4gII1jZW97hFNM1zQgEDvmtAVBVAs56n062dVA3W9cYVEnneo0wONO1hHtUCzT81wCpI11nRgSCba922TTI+0-UVpmlZOSZ1MgNBVTV50vW9OQ5V9+WwOVojDv2WBpm0dahjmox5lEMRTP+CkiCT2a7KpmZsecdxQMEXjVbVdD1WETUtagUAGg0Eojo+DREygZO4TTslAYzFHhhx8PYMu+POlgibJqmLRfhJsjFrT8vkS8StXFiyDelgvowH2GsAJJUHdNrCiBxWCCAsiziBXycF2jnrgaXFa3UhCzhgKspqLBMh6rkvINLBuy7+xsQSApxo2DE6cFxtspSD3ZqRCwqW1Q8ZLFykjylI4cV1I1fid2mcTcZUBc1A5eVw3tdd1I-tgM370wJ931UHDyaI8j1cg+jE4gegiKo4k2mMXpLPCgEX1IOdP6AYRKcvSvum6ygSt2hUkgaDGYtYK26JGCEE4APQAFQvxOMAv-AqCLbbN8wF0d0fh-ClV9B-F+T8JwBFKnFPkAp2JXFfu-K4n8YD2ywHlBAkQ-4E2IASH+C0OCcBgCAQhxBmo-DQAIQWMA1CdFmnUcBkCrgUPYNQ1Qc47bJmjhrRo3Zhj8MKo5DOW4YDxXgcKJB4C0EYIxNgrhodbYEKISQshOCNYAPdEwicCiBzmR4cmMcki37SLvs4VISwPS6KwCKfARBtFXFFAQQgQ5YzSjsXKbK9obBuPFoLWOKZmi6H4M4Twvj6iC3OGQUIqJ75SBcQYuoZiH5BzoLNThN9EnYE0mkYJMQcgRlytjX6FUYAAEUEBSDADsGgaB2avDMHaIp8xYB0Iwcmd4XJwkylUEEkQMQwk3x6VAU44dI4JPVsmYZASdZ5OcKcYYABHSpZkal1OeEOCpVS1n1Jev6EqQZcn9PmRGN2rw1B8g6F0oZEsJzdIliYCI-FipEIANoAF0YDmGGI8m4kRnYkjzqIZAOdEgvK4F8n5SQnb4h6jaL5pxgCjMeV8cxkg1aPOsWORIrzyAuhcAATXIJ875IooBpLxLOR5TjYDmE0jSr564P4oJZaytlbKn5PxgAAPTyEAA
Steps to reproduce
import { useMutationState } from '@tanstack/react-query'
type MyData = { data: string[] }
type MyError = { code: number; message: string }
type MyVars = { id: number }
const result = useMutationState<
MutationState<MyData, MyError, MyVars>
>({
filters: { mutationKey: ['KEY'] },
select: ({ state }) => state,
})
// Type '({ state }: Mutation<unknown, Error, unknown, unknown>) => MutationState<unknown, Error, unknown, unknown>' is not assignable to type '(mutation: Mutation<unknown, Error, unknown, unknown>) => MutationState<{ data: string[]; }, { code: number; message: string; }, { id: number; }, unknown>'.Expected behavior
When using filters.mutationKey to target a known mutation, the generic arguments should be propagated to the select callback:
select: (mutation: Mutation<MyData, MyError, MyVars>) => mutation.state
Current workaround - explicitly casting inside select:
select: (mutation) =>
mutation.state as MutationState<MyData, MyError, MyVars>
How often does this bug happen?
None
Screenshots or Videos
No response
Platform
All
Tanstack Query adapter
react-query
TanStack Query version
v5.59.15
TypeScript version
v5.9.3
Additional context
No response
