next.js

a7d68718 - turbo-tasks: copy tasks on their first modification during a snapshot (#99649)

turbo-tasks: copy tasks on their first modification during a snapshot (#99649) ### What? During a snapshot, a task's first modification now copies the task's pre-mutation state whenever any of its categories is part of the snapshot, whichever category the modification touches. A `None` marker is inserted only for tasks with no modified category. ### Why? `track_modification` used to decide based on the touched category only. That let a snapshot persist inconsistent state. Take a task with dirty meta and clean data: 1. The snapshot begins. 2. Data is modified. Data wasn't part of the snapshot, so only a `None` marker is inserted. 3. Meta is modified. A marker is already present, so nothing is copied. 4. Persistence encodes the live meta, already mutated by step 3. ### How? The design is otherwise unchanged: `*_modified_during_snapshot` bits, `None` markers and the promotion in `end_snapshot` all stay, and nothing new happens inside the operation exclusion. Only the first-modification check in `track_modification_internal` changes, from "is the touched category modified" to "is any category modified". The copy still encodes with the live modified bits, so categories that weren't part of the snapshot aren't persisted. A regression test covers the sequence above. It checks that the persisted item carries the pre-snapshot meta and no data, and that both modifications are left for the next snapshot. <!-- NEXT_JS_LLM --> <!-- fleet 98a896e8-00fa-4f81-97f0-48bd49e2a9a2 --> Co-authored-by: vercel-fleet-prod[bot] <318278635+vercel-fleet-prod[bot]@users.noreply.github.com> Co-authored-by: Tobias Koppers <1365881+sokra@users.noreply.github.com> Co-authored-by: Luke Sandberg <210140+lukesandberg@users.noreply.github.com>