Commit `8bfc8934a6`

8bfc8934a6c1a386392321f2531027c489c31c2d

parent: 17d0f6db92

Unsigned

cmc <hello@cleberg.net> · 2026-07-16 04:18 UTC

fix: derive inbox activity from mail, not thread.updated

Thread.updated is the root email's insert time. It never advances when a reply
arrives, despite the name and despite the schema describing threads as ordered
"most recently bumped". sr.ht returns updated seven seconds after root.date on
a thread carrying four replies:

    subject: "Re: test post"
    updated: 2026-07-16T03:44:55Z
    replies: 4
    root:    { date: 2026-07-15T22:44:48-05:00 }

The app fed that field into lastActivityAt everywhere, so a reply to an old
thread was invisible: it did not mark the thread unread, did not raise it in the
list, and did not update the timestamp beside it.

This was inert until the unread baseline landed, because an absent view record
returned unread unconditionally and the date was never compared to anything. The
baseline did not break unread; it was the first code to depend on that field
meaning what it says.

Use MailingList.emails instead, which is real reverse-chronological arrival
data, keyed by thread root id. The scan stops once it is older than the cutoff,
so a quiet list costs one page and a busy one costs only what is new. Threads
with nothing in the window keep the root timestamp and stay read, which they
already were. Failure returns empty activity rather than throwing: unread is a
decoration and should not take the thread list down with it.

Uses Email.received rather than Email.date — received is server-side and
non-null, date comes from the sender's header and is neither.

Layout: unified · split

Hutch/Networking/MailingListActivity.swift added +135

@@ -0,0 +1,135 @@
	1	import Foundation
	2
	3	// MARK: - Response types (file-private to avoid @MainActor Decodable issues)
	4
	5	private struct ListEmailsResponse: Decodable, Sendable {
	6	let list: ListEmailsPayload?
	7	}
	8
	9	private struct ListEmailsPayload: Decodable, Sendable {
	10	let emails: ListEmailPage
	11	}
	12
	13	private struct ListEmailPage: Decodable, Sendable {
	14	let results: [ListEmailPayload]
	15	let cursor: String?
	16	}
	17
	18	private struct ListEmailPayload: Decodable, Sendable {
	19	/// When sr.ht received the mail. Unlike `date`, which comes from the sender's
	20	/// Date: header and is both nullable and not to be trusted, this is
	21	/// server-authoritative.
	22	let received: Date
	23	let thread: ListEmailThread
	24	}
	25
	26	private struct ListEmailThread: Decodable, Sendable {
	27	let root: ListEmailThreadRoot
	28	}
	29
	30	private struct ListEmailThreadRoot: Decodable, Sendable {
	31	let id: Int
	32	}
	33
	34	// MARK: - Activity
	35
	36	/// When each thread on a mailing list last received mail.
	37	///
	38	/// `Thread.updated` cannot answer this. Despite its name, and despite the schema
	39	/// describing threads as ordered "most recently bumped", it is the root email's
	40	/// insert time and never advances when a reply arrives — sr.ht reports `updated`
	41	/// seven seconds after `root.date` on a thread carrying four replies. Anything
	42	/// built on it silently treats thread creation as activity.
	43	///
	44	/// `MailingList.emails` is reverse-chronological arrival data, so it can.
	45	struct MailingListActivity: Sendable {
	46	private let newestByRootEmailID: [Int: Date]
	47
	48	init(newestByRootEmailID: [Int: Date] = [:]) {
	49	self.newestByRootEmailID = newestByRootEmailID
	50	}
	51
	52	/// The newest arrival in the thread rooted at `rootEmailID`.
	53	///
	54	/// Falls back to `fallback` for threads with nothing inside the scanned
	55	/// window, which are by definition older than the cutoff and therefore read.
	56	func lastActivity(rootEmailID: Int, fallback: Date) -> Date {
	57	guard let newest = newestByRootEmailID[rootEmailID] else { return fallback }
	58	return max(newest, fallback)
	59	}
	60	}
	61
	62	enum MailingListActivityLoader {
	63
	64	private static let listEmailsQuery = """
	65	query listActivity($rid: ID!, $cursor: Cursor) {
	66	list(rid: $rid) {
	67	emails(cursor: $cursor) {
	68	results {
	69	received
	70	thread { root { id } }
	71	}
	72	cursor
	73	}
	74	}
	75	}
	76	"""
	77
	78	/// Scans the list's mail newest-first and stops once it is older than
	79	/// `cutoff`, so a quiet list costs a single page and a busy one costs only
	80	/// what has arrived since.
	81	///
	82	/// `maxPages` bounds the scan. An account carrying pre-existing read state has
	83	/// a `distantPast` cutoff, which would otherwise walk the entire archive;
	84	/// threads beyond the window keep their fallback date and stay read, which is
	85	/// what they already were.
	86	///
	87	/// Returns empty activity on failure rather than throwing: unread is a
	88	/// decoration, and losing it should not fail the thread list around it.
	89	static func load(
	90	client: SRHTClient,
	91	listRID: String,
	92	since cutoff: Date,
	93	maxPages: Int = 3
	94	) async -> MailingListActivity {
	95	var newest: [Int: Date] = [:]
	96	var cursor: String?
	97	var pagesFetched = 0
	98
	99	while pagesFetched < maxPages {
	100	var variables: [String: any Sendable] = ["rid": listRID]
	101	if let cursor {
	102	variables["cursor"] = cursor
	103	}
	104
	105	let response: ListEmailsResponse
	106	do {
	107	response = try await client.execute(
	108	service: .lists,
	109	query: listEmailsQuery,
	110	variables: variables,
	111	responseType: ListEmailsResponse.self
	112	)
	113	} catch {
	114	return MailingListActivity(newestByRootEmailID: newest)
	115	}
	116
	117	guard let page = response.list?.emails else { break }
	118	pagesFetched += 1
	119
	120	for email in page.results {
	121	let rootID = email.thread.root.id
	122	if let existing = newest[rootID], existing >= email.received { continue }
	123	newest[rootID] = email.received
	124	}
	125
	126	// Reverse chronological, so once a page ends older than the cutoff
	127	// nothing further back can matter.
	128	if let oldest = page.results.map(\.received).min(), oldest <= cutoff { break }
	129	guard let next = page.cursor, !next.isEmpty else { break }
	130	cursor = next
	131	}
	132
	133	return MailingListActivity(newestByRootEmailID: newest)
	134	}
	135	}

Hutch/Views/Home/HomeViewModel.swift +11 −2

         var cursor: String?
         var unreadThreads: [InboxThreadSummary] = []
+        // thread.updated is the root email's insert time and never advances when a
+        // reply lands, so activity has to come from the list's mail feed.
+        let activity = await MailingListActivityLoader.load(
+            client: client,
+            listRID: mailingList.rid,
+            since: InboxReadStateStore.baseline(defaults: defaults) ?? .distantPast
+        )
         while true {
             var variables: [String: any Sendable] = ["rid": mailingList.rid]
             if let cursor {
             let response = cached.value
             let unreadThreadSummaries = response.list.threads.results.compactMap { thread -> InboxThreadSummary? in
+                let lastActivityAt = activity.lastActivity(rootEmailID: thread.root.id, fallback: thread.updated)
                 let summary = InboxThreadSummary(
                     rootEmailID: thread.root.id,
                     rootMessageID: thread.root.messageID,
                     listOwner: mailingList.owner,
                     subject: thread.subject,
                     latestSender: thread.sender,
-                    lastActivityAt: thread.updated,
+                    lastActivityAt: lastActivityAt,
                     messageCount: thread.replies + 1,
                     repo: InboxThreadUtilities.deriveRepositoryName(from: mailingList.name),
                     containsPatch: thread.root.patch != nil || thread.subject.localizedCaseInsensitiveContains("[patch"),
                     isUnread: InboxReadStateStore.isUnread(
                         threadID: "\(mailingList.rid)#\(InboxThreadSummary.normalizationKey(for: thread.subject))",
-                        lastActivityAt: thread.updated,
+                        lastActivityAt: lastActivityAt,
                         defaults: defaults
                     )
                 )

Hutch/Views/Projects/ProjectMailingListView.swift +17 −4

                 responseType: ProjectMailingListThreadsResponse.self
             )
+            let activity = await MailingListActivityLoader.load(
+                client: client,
+                listRID: mailingList.rid,
+                since: InboxReadStateStore.baseline(defaults: defaults) ?? .distantPast
+            )
             threads = deduplicateThreads(
-                response.list.threads.results.map(makeSummary(from:))
+                response.list.threads.results.map { makeSummary(from: $0, activity: activity) }
             )
         } catch {
             self.error = "Failed to load mailing list"
         NeedsAttentionSnapshotStore.adjustUnreadInboxThreads(by: -unreadThreads.count, accountID: accountID)
     }
-    private func makeSummary(from thread: ProjectMailingListThreadPayload) -> InboxThreadSummary {
+    private func makeSummary(
+        from thread: ProjectMailingListThreadPayload,
+        activity: MailingListActivity
+    ) -> InboxThreadSummary {
         let normalizedSubject = thread.subject
             .replacingOccurrences(of: #"\s+"#, with: " ", options: .regularExpression)
             .trimmingCharacters(in: .whitespacesAndNewlines)
             .lowercased()
         let threadID = "\(mailingList.rid)#\(normalizedSubject)"
+        // thread.updated is the root email's insert time and never advances when a
+        // reply lands, so activity has to come from the list's mail feed.
+        let lastActivityAt = activity.lastActivity(rootEmailID: thread.root.id, fallback: thread.updated)
         return InboxThreadSummary(
             rootEmailID: thread.root.id,
             rootMessageID: thread.root.messageID,
             listOwner: mailingList.owner,
             subject: thread.subject,
             latestSender: thread.sender,
-            lastActivityAt: thread.updated,
+            lastActivityAt: lastActivityAt,
             messageCount: thread.replies + 1,
             repo: nil,
             containsPatch: thread.root.patch != nil || thread.subject.localizedCaseInsensitiveContains("[patch"),
-            isUnread: InboxReadStateStore.isUnread(threadID: threadID, lastActivityAt: thread.updated, defaults: defaults)
+            isUnread: InboxReadStateStore.isUnread(threadID: threadID, lastActivityAt: lastActivityAt, defaults: defaults)
         )
     }

HutchTests/MailingListActivityTests.swift added +77

@@ -0,0 +1,77 @@
	1	import Foundation
	2	import Testing
	3	@testable import Hutch
	4
	5	struct MailingListActivityTests {
	6
	7	@Test
	8	func usesTheNewestArrivalOverTheRootTimestamp() {
	9	// The case that started this: sr.ht reports thread.updated seven seconds
	10	// after the root email on a thread carrying four replies, so the fallback
	11	// must lose to real arrival data.
	12	let rootInsert = Date(timeIntervalSince1970: 1_000)
	13	let newestReply = Date(timeIntervalSince1970: 5_000)
	14	let activity = MailingListActivity(newestByRootEmailID: [42: newestReply])
	15
	16	#expect(activity.lastActivity(rootEmailID: 42, fallback: rootInsert) == newestReply)
	17	}
	18
	19	@Test
	20	func fallsBackForThreadsOutsideTheScannedWindow() {
	21	// Threads with nothing new are absent from the feed scan; they keep the
	22	// root timestamp, which is older than any cutoff and so reads as read.
	23	let rootInsert = Date(timeIntervalSince1970: 1_000)
	24	let activity = MailingListActivity(newestByRootEmailID: [:])
	25
	26	#expect(activity.lastActivity(rootEmailID: 42, fallback: rootInsert) == rootInsert)
	27	}
	28
	29	@Test
	30	func neverGoesBackwardsFromTheFallback() {
	31	// A root inserted after the newest scanned reply must not age the thread
	32	// backwards.
	33	let rootInsert = Date(timeIntervalSince1970: 9_000)
	34	let staleReply = Date(timeIntervalSince1970: 5_000)
	35	let activity = MailingListActivity(newestByRootEmailID: [42: staleReply])
	36
	37	#expect(activity.lastActivity(rootEmailID: 42, fallback: rootInsert) == rootInsert)
	38	}
	39
	40	@Test
	41	func tracksThreadsIndependently() {
	42	let activity = MailingListActivity(newestByRootEmailID: [
	43	1: Date(timeIntervalSince1970: 5_000),
	44	2: Date(timeIntervalSince1970: 7_000)
	45	])
	46	let fallback = Date(timeIntervalSince1970: 1_000)
	47
	48	#expect(activity.lastActivity(rootEmailID: 1, fallback: fallback) == Date(timeIntervalSince1970: 5_000))
	49	#expect(activity.lastActivity(rootEmailID: 2, fallback: fallback) == Date(timeIntervalSince1970: 7_000))
	50	#expect(activity.lastActivity(rootEmailID: 3, fallback: fallback) == fallback)
	51	}
	52
	53	@Test
	54	func newMailInAnOldThreadReadsAsUnread() {
	55	let suiteName = "MailingListActivityTests-\(UUID().uuidString)"
	56	let defaults = UserDefaults(suiteName: suiteName)!
	57	defer { defaults.removePersistentDomain(forName: suiteName) }
	58
	59	let signIn = Date(timeIntervalSince1970: 5_000)
	60	InboxReadStateStore.establishBaselineIfNeeded(now: signIn, defaults: defaults)
	61
	62	// A thread rooted long before sign-in, with a reply after it. Keyed on
	63	// thread.updated this reads as read, which was the bug.
	64	let rootInsert = Date(timeIntervalSince1970: 1_000)
	65	let replyAfterSignIn = Date(timeIntervalSince1970: 6_000)
	66	let activity = MailingListActivity(newestByRootEmailID: [42: replyAfterSignIn])
	67	let lastActivityAt = activity.lastActivity(rootEmailID: 42, fallback: rootInsert)
	68
	69	#expect(
	70	InboxReadStateStore.isUnread(
	71	threadID: "list#old thread",
	72	lastActivityAt: lastActivityAt,
	73	defaults: defaults
	74	)
	75	)
	76	}
	77	}

Commit 8bfc8934a6

Commit `8bfc8934a6`