From b40d3f7ca3f92373eca8dd0683d37183559c78e6 Mon Sep 17 00:00:00 2001 From: tv Date: Sun, 8 Nov 2026 19:48:45 +0000 Subject: document: tell whether a document holds a change without building it MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit With the policy's reads kept, judging a change still costs about one read (some 3.5 µs), and so does judging without a policy: what is left is At::new, which asks get_change_by_hash for each head. Automerge builds the change again from the document's operations to answer, at a cost growing with its history. Screening asks it again for every candidate and every dependency, and sync for heads. Ask by the missing dependencies instead (changes::holds), which look the hash up: one the document holds is not among them. A change queued in the document, waiting for its dependencies, isn't either; but then some are missing, and only then is it asked the slow way. Every check of whether a document holds a change goes through it. --- src/access/rules.rs | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) (limited to 'src/access/rules.rs') diff --git a/src/access/rules.rs b/src/access/rules.rs index 3aba0ba..bef9a13 100644 --- a/src/access/rules.rs +++ b/src/access/rules.rs @@ -125,7 +125,7 @@ pub(crate) fn judge_reading( // The first epoch's: the first change a document holds, as it comes to an empty // one, or as it is in one (judged again, `swarm::refusals`). let root = if epoch.generation == 0 { - doc.get_heads().is_empty() || doc.get_change_by_hash(&change.hash).is_some() + doc.get_heads().is_empty() || crate::document::changes::holds(doc, &change.hash) } else { change.hash.0 == epoch.id }; -- cgit v1.3.1