fix(graphcache): Mutable links on InMemoryData store

urql-graphql / urql

The highly customizable and versatile GraphQL client with which you add on features like normalized caching as you grow.

MIT License

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Summary

When cache.resolve returns a list of entity links, i.e. an array link, a user may be tempted to mutate this list before writing it back to the store.

This can have unforeseen consequences if:

cache.link then doesn't write to the same layer
cache.link isn't called at all
the array is completely changed and then read back in an unrelated operation

This is because, unlike cache.link, cache.resolve doesn't make a copy of links before returning them. This means that mutating a link array leads to direct modifications to the internal caching layer.

Set of changes

Call ensureLink before returning the links via cache.resolve to copy them

urql-graphql / urql

fix(graphcache): Mutable links on InMemoryData store #3516

Summary

Set of changes

🦋 Changeset detected