Ensure subscriptions adhere to the errorPolicy

[jerelmiller]

Fixes #10559

Errors returned in subscriptions payloads are always thrown, regardless of the error policy. With this change, the next function is now called if the errorPolicy is set to all or ignore. In the case of ignore, the errors property is stripped off the result.

NOTE: Protocol errors are still thrown regardless of the error policy. According to our docs, errorPolicy only changes how GraphQL errors are handled.

NOTE: useSubscription and subscribeToMore do not currently allow errorPolicy as a valid option, so these are not tested with this change. Since that is technically a new "feature", I've opted to wait to add this functionality in a patch release and instead will consider this as part of the next minor release. See #11165 to track the progress on this missing functionality.

Checklist:

• If this PR contains changes to the library itself (not necessary for e.g. docs updates), please include a changeset (see CONTRIBUTING.md)
• If this PR is a new feature, please reference an issue where a consensus about the design was reached (not necessary for small changes)
• Make sure all of the significant new logic is covered by tests

[changeset-bot]

🦋 Changeset detected

Latest commit: 6110dc3

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

This PR includes changesets to release 1 package

Name	Type
@apollo/client	Patch

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[github-actions]

size-limit report 📦

Path	Size
dist/apollo-client.min.cjs	37.18 KB (+0.05% 🔺)
import { ApolloClient, InMemoryCache, HttpLink } from "dist/main.cjs"	43.65 KB (+0.05% 🔺)
import { ApolloClient, InMemoryCache, HttpLink } from "dist/main.cjs" (production)	42.27 KB (+0.04% 🔺)
import { ApolloClient, InMemoryCache, HttpLink } from "dist/index.js"	32.41 KB (+0.05% 🔺)
import { ApolloClient, InMemoryCache, HttpLink } from "dist/index.js" (production)	31.23 KB (+0.09% 🔺)
import { ApolloProvider } from "dist/react/index.js"	1.21 KB (0%)
import { ApolloProvider } from "dist/react/index.js" (production)	1.2 KB (0%)
import { useQuery } from "dist/react/index.js"	4.29 KB (0%)
import { useQuery } from "dist/react/index.js" (production)	4.1 KB (0%)
import { useLazyQuery } from "dist/react/index.js"	4.59 KB (0%)
import { useLazyQuery } from "dist/react/index.js" (production)	4.41 KB (0%)
import { useMutation } from "dist/react/index.js"	2.52 KB (0%)
import { useMutation } from "dist/react/index.js" (production)	2.5 KB (0%)
import { useSubscription } from "dist/react/index.js"	2.23 KB (0%)
import { useSubscription } from "dist/react/index.js" (production)	2.19 KB (0%)
import { useSuspenseQuery } from "dist/react/index.js"	4.73 KB (0%)
import { useSuspenseQuery } from "dist/react/index.js" (production)	4.16 KB (0%)
import { useBackgroundQuery } from "dist/react/index.js"	4.26 KB (0%)
import { useBackgroundQuery } from "dist/react/index.js" (production)	3.67 KB (0%)
import { useReadQuery } from "dist/react/index.js"	2.94 KB (0%)
import { useReadQuery } from "dist/react/index.js" (production)	2.88 KB (0%)
import { useFragment } from "dist/react/index.js"	2.07 KB (0%)
import { useFragment } from "dist/react/index.js" (production)	2.02 KB (0%)

[alessbell]

@jerelmiller and I synced offline on this - LGTM 👍