Copyable snapshots#16
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While snapshots are simple data types, they are not necessarily _value_ types, and so mutating a reference snapshot effectively mutates _all_ references to that snapshot. This is not a problem with the built-in tools, like `expect`, but for integrations that hold onto snapshots over time (like ComposableArchitecture 2.0), explicit copying is needed at times.
mbrandonw
approved these changes
Jun 15, 2026
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While snapshots are simple data types, they are not necessarily value types, and so mutating a reference snapshot effectively mutates all references to that snapshot.
This is not a problem with the built-in tools like
expect, but for integrations that hold onto snapshots over time (like ComposableArchitecture 2.0'sTestStore), explicit copying is needed at times.