test: pin the collapse of a symbol-keyed operator - #17
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DELETE is interpreted at any merged object-field position, including an own enumerable symbol key. Classifying a delta by its string keys alone therefore reads a symbol-keyed DELETE as an empty container and materializes one, which over a wrong-shaped base replaces a live value the miss never wrote. Nothing pinned that: symbols were covered for merging and for tombstone purity, but never as the key carrying a delete that finds nothing. Co-Authored-By: Claude Opus 5 <noreply@anthropic.com>
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DELETEis interpreted at any merged object-field position, including an ownenumerable symbol key. Classifying a delta by its string keys alone therefore
reads a symbol-keyed
DELETEas an empty container and materializes one, whichover a wrong-shaped base replaces a live value the miss never wrote.
Symbols were already covered for merging and for tombstone purity, but never as
the key carrying a delete that finds nothing.
Non-vacuity: changing
mentioned = truetoif (typeof key === "string") mentioned = true;insrc/merge.tskills this test and nothing else inmerge.test.ts.🤖 Generated with Claude Code
Summary by cubic
Pins merge semantics for a symbol-keyed
DELETE: when the operator targets a missing symbol key, it collapses and leaves the base unchanged instead of materializing an empty object that could replace a live value. Previously, classifying deltas by string keys could misread a symbol-keyedDELETEas an empty container.test/merge.test.tsthat asserts collapse on an absent symbol key and preserves a wrong-shaped base.Written for commit 12dc9a9. Summary will update on new commits.