Add static is methods to error types for type narrowing

[jerelmiller]

Followup to #12539 (comment)

Make it easier to type-narrow an error type by adding static is methods to each error type. This is a bit more robust than just using instanceof since that might fail due to e.g. multiple versions of Apollo Client installed.

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Build ID: b4d01c490531d0d804e8b28c

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[github-actions]

size-limit report 📦

Path	Size
import { ApolloClient, InMemoryCache, HttpLink } from "@apollo/client" (CJS)	42.09 KB (+0.3% 🔺)
import { ApolloClient, InMemoryCache, HttpLink } from "@apollo/client" (production) (CJS)	37.71 KB (+0.44% 🔺)
import { ApolloClient, InMemoryCache, HttpLink } from "@apollo/client"	32.25 KB (+0.35% 🔺)
import { ApolloClient, InMemoryCache, HttpLink } from "@apollo/client" (production)	27.3 KB (+0.4% 🔺)
import { ApolloProvider } from "@apollo/client/react"	5.12 KB (0%)
import { ApolloProvider } from "@apollo/client/react" (production)	962 B (0%)
import { useQuery } from "@apollo/client/react"	10.82 KB (0%)
import { useQuery } from "@apollo/client/react" (production)	6.61 KB (0%)
import { useLazyQuery } from "@apollo/client/react"	6.3 KB (0%)
import { useLazyQuery } from "@apollo/client/react" (production)	2.13 KB (0%)
import { useMutation } from "@apollo/client/react"	5.71 KB (0%)
import { useMutation } from "@apollo/client/react" (production)	1.53 KB (0%)
import { useSubscription } from "@apollo/client/react"	6.01 KB (0%)
import { useSubscription } from "@apollo/client/react" (production)	1.83 KB (0%)
import { useSuspenseQuery } from "@apollo/client/react"	7.77 KB (0%)
import { useSuspenseQuery } from "@apollo/client/react" (production)	3.57 KB (0%)
import { useBackgroundQuery } from "@apollo/client/react"	7.57 KB (0%)
import { useBackgroundQuery } from "@apollo/client/react" (production)	3.42 KB (0%)
import { useLoadableQuery } from "@apollo/client/react"	7.59 KB (0%)
import { useLoadableQuery } from "@apollo/client/react" (production)	3.44 KB (0%)
import { useReadQuery } from "@apollo/client/react"	5.79 KB (0%)
import { useReadQuery } from "@apollo/client/react" (production)	1.62 KB (0%)
import { useFragment } from "@apollo/client/react"	5.84 KB (0%)
import { useFragment } from "@apollo/client/react" (production)	1.68 KB (0%)

[jerelmiller]

I figure its best to try instanceof first since its harder to spoof. If that fails for whatever reason (multiple versions of the library for example), then we use the lower fidelity check on error.name to see if it matches.

[phryneas]

I understand the thought, but "harder to spoof" doesn't seem like a valid argument here: if someone were to spoof it, they could just set the name and the next check would still succeed - no matter if we optionally check for instanceof first or not.

If we want to prevent spoofing, we could use the mechanism that Error.isErrorand Array.isArray use:
Create a property with a well-known symbol key and check for that. (The native solutions use a [[ErrorData]] internal engine slot for that, which we obviously cannot do.)

Really not sure if that's worth it, though, and it might make serialization harder.

As it is right now, I believe the instanceof would only be beneficial if someone had a valid CombinedGraphQLErrors instance, but changed the value of name manually - and I'm not sure if we should waste bundle size on supporting that.

[jerelmiller]

Check Symbol.for('apollo.error') property and compare name

[phryneas]

Setting this as "Request Changes" so we don't forget discussing the instanceof check.

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🦋 Changeset detected

Latest commit: e4bb1e8

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

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@apollo/client	Minor

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[phryneas]

Would be nice to test this with structuredClone to simulate an error from another realm, but we are polyfilling structuredClone with JSON.parse/JSON.stringify here so that won't work.