Implement java.util.List on sequence wrappers - #26
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Read and write array-list and linked-array-list views now implement the full read-only java.util.List contract instead of only toArray: size, get with bounds checks on both ends, indexOf, containsAll, listIterator, subList, and typed toArray. Mutating methods throw UnsupportedOperationException. Sublists and iterators are live: a sublist taken inside a transaction reflects later assocs. Shared methods delegate to a Collections.unmodifiableList over an AbstractList proxy that streams the wrapper's seq, so no materialization happens. Since the wrappers are now List instances, java.util.ArrayList.equals accepts them and equality is symmetric with Java lists, including HashSet membership. Co-Authored-By: Claude Fable 5.1 <noreply@anthropic.com>
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Routing the transaction wrappers' iterator through listIterator made every element read go through putCursor, a write path that copies index nodes. Since coll-reduce dispatches on Iterable for these types, reduce, into and mapv inside swap! duplicated the whole list in the append-only file on every transaction (48 KB per 5000-element vector, 115 KB per list). Iterate the seq again, which walks cursors without copying. The plain iterator is therefore not live after assoc; listIterator and subList iterators still are, and the test now asserts liveness only for those. Co-Authored-By: Claude Fable 5.1 <noreply@anthropic.com>
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Summary
Stacked on #25. Read and write views over array lists and linked array lists now implement the full read-only
java.util.Listcontract, replacing the previousjava.util.Collectionimplementation that only providedtoArray.size,isEmpty,getwithIndexOutOfBoundsExceptionfor negative and past-the-end indices,contains,containsAll,indexOf,lastIndexOf,listIteratorwith and without a start index,subList, and bothtoArrayoverloads including the typed-array form. Every mutating method throwsUnsupportedOperationException, including on sublists and list iterators.Collections.unmodifiableListover anAbstractListproxy inxitdb.util.collectionthat streams the wrapper's seq. A sublist taken from a write view inside a transaction reflects laterassoccalls.java.util.ArrayList.equalsrequires the other operand to be aList, so it previously returned false against a stored sequence even though the reverse comparison was true. Both directions now agree, andhashCodematches, so views and Java lists find each other in aHashSet.Test plan
clojure -M:test: 237 tests, 3,157 assertions, 0 failurestoArraybuffers, bidirectionallistIterator, sublist bounds, live sublists across an in-transactionassoc, and every mutator throwingequals,hashCode, andHashSetmembership in both operand orders againstjava.util.ArrayList🤖 Generated with Claude Code