Fix: detecting fragment usage in maskFragments()

[takumiyoshikawa]

Background

I have reported the following issue to the gql.tada repository.
0no-co/gql.tada#500

Summary

When using gql.tada's maskFragments() function, the colocated fragments check was incorrectly reporting fragments as
unused, even though they were being used.

This PR fixes the false positive by detecting fragment usage in maskFragments() calls.

Example

import { maskFragments } from './graphql';
// Previously: "Unused co-located fragment PokemonFields" warning
// Now: No warning (correctly detected as used)
import { Pokemon, PokemonFields } from './fragment';

const data = { id: '1', name: 'Pikachu', fleeRate: 0.1 };
const x = maskFragments([PokemonFields], data);

console.log(Pokemon);

Changes

• Add isMaskFragmentsCall() check in ast/checks.ts
• Add findAllMaskFragmentsCalls() helper in ast/index.ts
• Update diagnostics.ts to detect fragments passed to maskFragments([...], data)
• Add e2e test for maskFragments usage

Test plan

• Added e2e test case should not warn about unused fragments when using maskFragments
• Run pnpm test:e2e

[changeset-bot]

🦋 Changeset detected

Latest commit: 214d770

The changes in this PR will be included in the next version bump.

This PR includes changesets to release 1 package

Name	Type
@0no-co/graphqlsp	Patch

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[takumiyoshikawa]

Currently, we only check whether maskFragments is being used by looking at the function name.
I’d like to improve this if there’s a better approach, but I haven’t found a good solution yet.

[takumiyoshikawa]

Thank you for the review. I’ve updated the commit suggestion accordingly.