Test: the 0.32 shared vectors, loaded by the app's own code

Loader tests for the three vector files flamenet-e2e docs/spec-0-32 adds, found through FLAMENET_CONTENT_KINDS_VECTORS, FLAMENET_TODAY_VECTORS and FLAMENET_HELLO_LINK_VECTORS, or in a flamenet-e2e checkout beside this one: - content kinds (app module): every written envelope parsed and written back by the engine's encoders, byte for byte; every envelope through Content.parse and the session's own gates (control traffic, and a move or an ending through ChatGames.receive), checked field by field. - Today (client module): TodayFile.verify on the sample, every case and the 512 KB edge; the sequence and If-None-Match through TodayFeed over a MockWebServer on this machine. - hello links (app module): the link cases through HelloLink.fromLink, as openHelloLink calls it, and the scan cases through prefillFor. Test files only. Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com>
2026-10-04 15:30:57 -04:00
parent 067e6fcf51
commit 4aa0d0f237
3 changed files with 541 additions and 0 deletions
@@ -0,0 +1,221 @@
+package io.flamenet.messenger.app
+
+import io.flamenet.e2e.Content
+import org.json.JSONArray
+import org.json.JSONObject
+import java.io.File
+import kotlin.test.Test
+import kotlin.test.assertEquals
+import kotlin.test.fail
+
+/**
+ * The 0.32 content kinds against the shared vectors, `content-kinds-v1.json`
+ * from flamenet-e2e (§6.31 to §6.35, §6.12, §6.10).
+ *
+ * Two halves. Every `written` envelope is parsed and written back with this
+ * app's own encoders, and the bytes must be the file's. Every envelope, written
+ * or read, goes through `Content.parse` and the checks the session applies
+ * before anything is drawn or taken (control traffic, a game move's own rules
+ * through `ChatGames.receive`), and what comes out must be what the file says,
+ * for the fields the case lists.
+ *
+ * The file is found through `FLAMENET_CONTENT_KINDS_VECTORS`, or in a
+ * flamenet-e2e checkout beside this one.
+ */
+class SharedVectorsContentKindsTest {
+    private val file: JSONObject by lazy {
+        val candidates =
+            listOfNotNull(
+                System.getenv("FLAMENET_CONTENT_KINDS_VECTORS"),
+                "../../flamenet-e2e/test/vectors/content-kinds-v1.json",
+                "../../../flamenet-e2e/test/vectors/content-kinds-v1.json",
+            ).map(::File)
+        val found =
+            candidates.firstOrNull { it.exists() }
+                ?: throw AssertionError("content-kinds-v1.json not found. Looked in: ${candidates.joinToString { it.absolutePath }}")
+        JSONObject(found.readText())
+    }
+
+    private val dropped = mapOf("verdict" to "dropped")
+
+    /** What this app makes of one plaintext, in the file's terms. */
+    private fun read(plaintext: String): Map<String, Any?> {
+        val c = Content.parse(plaintext)
+        if (c.raw == null) return mapOf("verdict" to "plain")
+        val common =
+            mapOf(
+                "mid" to c.messageId,
+                "gid" to c.groupId,
+                "forwarded" to c.isForwarded,
+                "ownTimer" to c.lifetimeSeconds,
+            )
+        when (c.kind) {
+            Content.Kind.RSVP -> {
+                val r = c.rsvp ?: return dropped
+                return common + mapOf("verdict" to "rsvp", "rsvp" to mapOf("eid" to r.eventId, "r" to r.answer, "n" to r.n))
+            }
+
+            Content.Kind.GAME_MOVE, Content.Kind.GAME_END -> {
+                // As the session takes them: one to one only, then the rules'
+                // own refusals before anything is built.
+                val g = c.game ?: return dropped
+                if (c.groupId != null) return dropped
+                if (ChatGames.receive(null, c.kind, g) == ChatGames.Received.Ignored) return dropped
+                return common + mapOf("verdict" to c.kind, "game" to game(g, c.kind))
+            }
+
+            Content.Kind.UNPOST -> {
+                val u = c.unpost ?: return dropped
+                return common + mapOf("verdict" to "unpost", "sid" to u.storyId, "set" to u.setId)
+            }
+
+            Content.Kind.EDIT -> {
+                val target = c.editOf
+                if (target != null) {
+                    return common + mapOf("verdict" to "edit", "story" to c.editsStory, "mid" to target, "caption" to c.text)
+                }
+            }
+        }
+        if (c.isControl || !c.isRenderable) return dropped
+        c.card?.let { card ->
+            val body = mutableMapOf<String, Any?>("d" to card.design, "msg" to card.msg)
+            card.to?.let { body["to"] = it }
+            card.from?.let { body["from"] = it }
+            card.open?.let { body["open"] = it }
+            return common + mapOf("verdict" to "card", "card" to body, "drawn" to card.shownDesign)
+        }
+        c.event?.let { e ->
+            val ev = mutableMapOf<String, Any?>("id" to e.id, "rev" to e.rev, "title" to e.title, "cancel" to e.cancelled)
+            if (e.start != null) {
+                ev["start"] = e.start
+                e.tz?.let { ev["tz"] = it }
+            } else {
+                ev["day"] = e.day
+                ev["dayCount"] = e.days ?: 1
+            }
+            e.place?.let { ev["place"] = it }
+            e.note?.let { ev["note"] = it }
+            return common +
+                mapOf("verdict" to "event", "ev" to ev, "allDay" to e.allDay, "endShown" to if (e.start != null) e.end else null)
+        }
+        if (c.kind == Content.Kind.GAME) {
+            c.game?.let { return common + mapOf("verdict" to "game", "game" to game(it, c.kind)) }
+        }
+        if (c.kind == Content.Kind.TEXT) {
+            val link = c.link?.let { mapOf("url" to it.url, "title" to it.title, "desc" to it.desc) }
+            return common + mapOf("verdict" to "text", "caption" to c.text, "lnk" to link)
+        }
+        if (c.text == "[unsupported attachment]" && c.attachment == null) return mapOf("verdict" to "unsupported")
+        return mapOf("verdict" to "other: ${c.kind}")
+    }
+
+    private fun game(
+        g: Content.Game,
+        kind: String,
+    ): Map<String, Any?> {
+        val out = mutableMapOf<String, Any?>("id" to g.id, "t" to g.type, "mine" to g.mine)
+        if (kind != Content.Kind.GAME) g.log?.let { out["log"] = it }
+        if (kind == Content.Kind.GAME_END) g.ending?.let { out["r"] = it }
+        return out
+    }
+
+    /** The bytes this app writes for what it read from [plaintext]. */
+    private fun write(plaintext: String): String? {
+        val c = Content.parse(plaintext)
+        val raw = c.raw ?: return null
+        val groupName = raw.optString("gname").takeIf { it.isNotEmpty() }
+        return when (c.kind) {
+            Content.Kind.CARD -> {
+                val card = c.card ?: return null
+                Content.card(card, c.messageId ?: return null, c.groupId, groupName, c.isForwarded)
+            }
+
+            Content.Kind.EVENT -> {
+                val event = c.event ?: return null
+                Content.event(event, c.messageId ?: return null, c.groupId, groupName, c.isForwarded)
+            }
+
+            Content.Kind.RSVP -> {
+                c.rsvp?.let { Content.rsvp(it, c.groupId) }
+            }
+
+            Content.Kind.GAME -> {
+                c.game?.let { Content.game(it, c.messageId ?: return null) }
+            }
+
+            Content.Kind.GAME_MOVE -> {
+                c.game?.let { Content.gameMove(it) }
+            }
+
+            Content.Kind.GAME_END -> {
+                c.game?.let { Content.gameEnd(it) }
+            }
+
+            Content.Kind.UNPOST -> {
+                val u = c.unpost ?: return null
+                u.storyId?.let { Content.unpostStory(it) } ?: u.setId?.let { Content.unpostStorySet(it) }
+            }
+
+            Content.Kind.EDIT -> {
+                if (c.editsStory) c.editOf?.let { Content.storyEdit(it, c.text) } else null
+            }
+
+            else -> {
+                null
+            }
+        }
+    }
+
+    /** JSON values and this app's values in one shape: whole numbers as Long, objects as maps. */
+    private fun plain(value: Any?): Any? =
+        when (value) {
+            null, JSONObject.NULL -> null
+            is JSONObject -> value.keys().asSequence().associateWith { plain(value.get(it)) }
+            is JSONArray -> (0 until value.length()).map { plain(value.get(it)) }
+            is Map<*, *> -> value.entries.associate { (k, v) -> k.toString() to plain(v) }
+            is List<*> -> value.map(::plain)
+            // org.json reads a fraction as a BigDecimal: kept as a fraction, never cut to a whole number.
+            is java.math.BigDecimal -> if (value.stripTrailingZeros().scale() <= 0) value.toLong() else value.toDouble()
+            is Double -> if (value == Math.floor(value) && !value.isInfinite()) value.toLong() else value
+            is Float -> plain(value.toDouble())
+            is Number -> value.toLong()
+            else -> value
+        }
+
+    @Test
+    fun `every written envelope is what this app writes, byte for byte`() {
+        val written = file.getJSONArray("written")
+        assertEquals(24, written.length())
+        val wrong = mutableListOf<String>()
+        for (i in 0 until written.length()) {
+            val one = written.getJSONObject(i)
+            val envelope = one.getString("envelope")
+            val mine = runCatching { write(envelope) }.getOrElse { "threw: $it" }
+            if (mine != envelope) wrong += "written '${one.getString("name")}': the file has $envelope, this app writes $mine"
+        }
+        println("content-kinds written: ${written.length()} cases, ${wrong.size} differ")
+        if (wrong.isNotEmpty()) fail(wrong.joinToString("\n"))
+    }
+
+    @Test
+    fun `every envelope reads the way the file says`() {
+        val cases = (0 until file.getJSONArray("written").length()).map { file.getJSONArray("written").getJSONObject(it) } +
+            (0 until file.getJSONArray("read").length()).map { file.getJSONArray("read").getJSONObject(it) }
+        assertEquals(132, cases.size)
+        val wrong = mutableListOf<String>()
+        for (one in cases) {
+            val envelope = one.getString("envelope")
+            val want = one.getJSONObject("reads")
+            val got = read(envelope)
+            for (key in want.keys().asSequence().sorted()) {
+                val expected = plain(want.get(key))
+                val actual = plain(got[key])
+                if (expected != actual) {
+                    wrong += "read '${one.getString("name")}': $key is $expected in the file, $actual here. Envelope: $envelope"
+                }
+            }
+        }
+        println("content-kinds read: ${cases.size} cases, ${wrong.size} fields differ")
+        if (wrong.isNotEmpty()) fail(wrong.joinToString("\n"))
+    }
+}
@@ -0,0 +1,55 @@
+package io.flamenet.messenger.app
+
+import org.json.JSONObject
+import java.io.File
+import kotlin.test.Test
+import kotlin.test.assertEquals
+import kotlin.test.fail
+
+/**
+ * Hello links against the shared vectors, `hello-link-v1.json` from
+ * flamenet-e2e (§6.34). The `link` cases go through what the app does with a
+ * link it is opened with ([HelloLink.fromLink], as `openHelloLink` calls it),
+ * and the `scan` cases through what a scanned code fills the add screen with
+ * ([prefillFor]). The `fragment` cases are the relay's /hi page, not this app.
+ *
+ * The file is found through `FLAMENET_HELLO_LINK_VECTORS`, or in a
+ * flamenet-e2e checkout beside this one.
+ */
+class SharedVectorsHelloLinkTest {
+    private val file: JSONObject by lazy {
+        val candidates =
+            listOfNotNull(
+                System.getenv("FLAMENET_HELLO_LINK_VECTORS"),
+                "../../flamenet-e2e/test/vectors/hello-link-v1.json",
+                "../../../flamenet-e2e/test/vectors/hello-link-v1.json",
+            ).map(::File)
+        val found =
+            candidates.firstOrNull { it.exists() }
+                ?: throw AssertionError("hello-link-v1.json not found. Looked in: ${candidates.joinToString { it.absolutePath }}")
+        JSONObject(found.readText())
+    }
+
+    @Test
+    fun `every link and scan case gives the address or refusal the file says`() {
+        val cases = file.getJSONArray("cases")
+        val checked = mutableMapOf("link" to 0, "scan" to 0)
+        val wrong = mutableListOf<String>()
+        for (i in 0 until cases.length()) {
+            val one = cases.getJSONObject(i)
+            val context = one.getString("context")
+            if (context != "link" && context != "scan") continue
+            val input = one.getString("input")
+            val want = if (one.isNull("expect")) null else one.getString("expect")
+            val got = if (context == "link") HelloLink.fromLink(input) else prefillFor(input)
+            if (got != want) {
+                wrong += "$context '${one.getString("name")}': the file says ${want ?: "refused"}, " +
+                    "this app gives ${got ?: "refused"}. Input: ${input.take(120)}"
+            }
+            checked[context] = checked.getValue(context) + 1
+        }
+        println("hello links: $checked checked, ${wrong.size} differ")
+        assertEquals(mapOf("link" to 37, "scan" to 18), checked)
+        if (wrong.isNotEmpty()) fail(wrong.joinToString("\n"))
+    }
+}
@@ -0,0 +1,265 @@
+package io.flamenet.client
+
+import okhttp3.mockwebserver.MockResponse
+import okhttp3.mockwebserver.MockWebServer
+import org.json.JSONArray
+import org.json.JSONObject
+import java.io.File
+import java.nio.file.Files
+import kotlin.test.Test
+import kotlin.test.assertEquals
+import kotlin.test.fail
+
+/**
+ * The Today file against the shared vectors, `today-v1.json` from
+ * flamenet-e2e (§8.12): which envelopes this app takes and why it refuses the
+ * rest, what a taken one holds, the 512 KB edge, which of two files the feed
+ * shows, and when it sends the stored ETag back.
+ *
+ * The file is found through `FLAMENET_TODAY_VECTORS`, or in a flamenet-e2e
+ * checkout beside this one.
+ */
+class SharedVectorsTodayTest {
+    private val file: JSONObject by lazy {
+        val candidates =
+            listOfNotNull(
+                System.getenv("FLAMENET_TODAY_VECTORS"),
+                "../../flamenet-e2e/test/vectors/today-v1.json",
+                "../../../flamenet-e2e/test/vectors/today-v1.json",
+            ).map(::File)
+        val found =
+            candidates.firstOrNull { it.exists() }
+                ?: throw AssertionError("today-v1.json not found. Looked in: ${candidates.joinToString { it.absolutePath }}")
+        JSONObject(found.readText())
+    }
+
+    private val keys: TodayFile.Keys by lazy {
+        val key = file.getJSONObject("key")
+        TodayFile.Keys(listOf(key.getString("public"))).also {
+            assertEquals(setOf(key.getString("kid")), it.byKid.keys)
+        }
+    }
+
+    private fun why(refusal: TodayFile.Refusal): String =
+        when (refusal) {
+            TodayFile.Refusal.TOO_LARGE -> "too-large"
+            TodayFile.Refusal.MALFORMED -> "malformed"
+            TodayFile.Refusal.UNKNOWN_VERSION -> "unknown-version"
+            TodayFile.Refusal.UNSIGNED -> "unsigned"
+            TodayFile.Refusal.UNKNOWN_KEY -> "unknown-key"
+            TodayFile.Refusal.BAD_SIGNATURE -> "bad-signature"
+            TodayFile.Refusal.BAD_BODY -> "bad-body"
+        }
+
+    /** What this app keeps at one of the file's paths. It has no `lat` or `lon` to keep. */
+    private fun valueAt(
+        path: String,
+        b: TodayFile.Bundle,
+    ): Any? {
+        val p = path.split(".")
+        fun blank(s: String?) = s?.takeIf { it.isNotEmpty() }
+        val fields: Map<String, Any?> =
+            when (p.first()) {
+                "headlines" -> b.headlines.getOrNull(p[1].toInt())?.let { mapOf("t" to it.title, "u" to it.url, "src" to blank(it.source)) }
+                "markets" ->
+                    b.markets.getOrNull(p[1].toInt())?.let {
+                        mapOf("sym" to it.symbol, "name" to it.name, "last" to it.last, "chg" to blank(it.change), "pct" to blank(it.percent))
+                    }
+                "weather" -> b.weather.getOrNull(p[1].toInt())?.let { mapOf("city" to it.name, "cc" to blank(it.country), "tz" to blank(it.zone)) }
+                "site" -> b.site?.let { mapOf("t" to it.title, "u" to it.url, "d" to it.description) }
+                "post" -> b.post?.let { mapOf("t" to it.title, "u" to it.url, "d" to it.description, "by" to it.by) }
+                "notes" -> return b.notes.getOrNull(p[1].toInt())
+                else -> null
+            } ?: return null
+        return fields[p.last()]
+    }
+
+    /** Characters as a reader counts them, which is how the file states lengths. */
+    private fun drawnLength(s: String): Int {
+        val breaks = java.text.BreakIterator.getCharacterInstance()
+        breaks.setText(s)
+        var n = 0
+        while (breaks.next() != java.text.BreakIterator.DONE) n++
+        return n
+    }
+
+    private fun plain(value: Any?): Any? =
+        when (value) {
+            null, JSONObject.NULL -> null
+            // org.json reads a fraction as a BigDecimal: kept as a fraction, never cut to a whole number.
+            is java.math.BigDecimal -> if (value.stripTrailingZeros().scale() <= 0) value.toLong() else value.toDouble()
+            is Double -> if (value == Math.floor(value) && !value.isInfinite()) value.toLong() else value
+            is Number -> value.toLong()
+            else -> value
+        }
+
+    /** Where this app's answer for one envelope differs from [want], in words. */
+    private fun unlike(
+        envelope: ByteArray,
+        want: JSONObject,
+    ): List<String> {
+        val verdict = want.getString("verdict")
+        return when (val got = TodayFile.verify(envelope, keys)) {
+            is TodayFile.Verdict.Refused -> {
+                if (verdict != "refuse") {
+                    listOf("refused (${why(got.why)}), the file takes it")
+                } else if (why(got.why) != want.optString("why")) {
+                    listOf("refused as ${why(got.why)}, the file says ${want.optString("why")}")
+                } else {
+                    emptyList()
+                }
+            }
+
+            is TodayFile.Verdict.Good -> {
+                if (verdict != "accept") return listOf("taken, the file refuses it (${want.optString("why")})")
+                val b = got.bundle
+                val e = want.optJSONObject("expect") ?: JSONObject()
+                val wrong = mutableListOf<String>()
+                if (e.has("date") && e.getString("date") != b.date) wrong += "date ${b.date}"
+                if (e.has("made") && e.getLong("made") != b.made) wrong += "made ${b.made}"
+                val counts = mapOf("headlines" to b.headlines.size, "markets" to b.markets.size, "cities" to b.weather.size, "notes" to b.notes.size)
+                for ((key, n) in counts) if (e.has(key) && e.getInt(key) != n) wrong += "$key $n, not ${e.getInt(key)}"
+                e.optJSONArray("days")?.let { days ->
+                    val expected = (0 until days.length()).map { days.getInt(it) }
+                    val mine = expected.indices.map { b.weather.getOrNull(it)?.days?.size ?: -1 }
+                    if (mine != expected) wrong += "days $mine, not $expected"
+                }
+                val present = mapOf("site" to (b.site != null), "post" to (b.post != null), "siteNote" to (b.siteNote != null))
+                for ((key, has) in present) if (e.has(key) && e.getBoolean(key) != has) wrong += "$key $has"
+                e.optJSONObject("lengths")?.let { lengths ->
+                    for (path in lengths.keys().asSequence().sorted()) {
+                        val n = drawnLength(valueAt(path, b) as? String ?: "")
+                        if (n != lengths.getInt(path)) wrong += "$path drawn $n long, not ${lengths.getInt(path)}"
+                    }
+                }
+                e.optJSONObject("fields")?.let { fields ->
+                    for (path in fields.keys().asSequence().sorted()) {
+                        val mine = plain(valueAt(path, b))
+                        val theirs = plain(fields.get(path))
+                        if (mine != theirs) wrong += "$path is $mine, not $theirs"
+                    }
+                }
+                wrong
+            }
+        }
+    }
+
+    @Test
+    fun `the sample, every case, and the 512 KB edge, as the file says`() {
+        val wrong = mutableListOf<String>()
+        val sample = file.getJSONObject("sample")
+        val sampleBytes = sample.getString("envelope").toByteArray(Charsets.UTF_8)
+        unlike(sampleBytes, sample).forEach { wrong += "the sample: $it" }
+        assertEquals(sample.getString("etag"), TodayFeed.etagOf(sampleBytes))
+
+        val cases = file.getJSONArray("cases")
+        assertEquals(33, cases.length())
+        for (i in 0 until cases.length()) {
+            val one = cases.getJSONObject(i)
+            unlike(one.getString("envelope").toByteArray(Charsets.UTF_8), one).forEach { wrong += "case '${one.getString("name")}': $it" }
+        }
+
+        val built = file.getJSONArray("built")
+        val text = sample.getString("envelope")
+        for (i in 0 until built.length()) {
+            val one = built.getJSONObject(i)
+            val pad = one.getInt("padTo") - sampleBytes.size - ",\"pad\":\"\"".length
+            val bytes = (text.dropLast(1) + ",\"pad\":\"" + "x".repeat(pad) + "\"}").toByteArray(Charsets.UTF_8)
+            assertEquals(one.getInt("padTo"), bytes.size)
+            unlike(bytes, one).forEach { wrong += "built '${one.getString("name")}': $it" }
+        }
+        println("today: the sample, ${cases.length()} cases and ${built.length()} built files, ${wrong.size} differences")
+        if (wrong.isNotEmpty()) fail(wrong.joinToString("\n"))
+    }
+
+    /** Every named file in the vectors, by name. */
+    private fun byName(): Map<String, ByteArray> {
+        val out = mutableMapOf<String, ByteArray>()
+        val sample = file.getJSONObject("sample")
+        out[sample.getString("name")] = sample.getString("envelope").toByteArray(Charsets.UTF_8)
+        val cases = file.getJSONArray("cases")
+        for (i in 0 until cases.length()) {
+            val one = cases.getJSONObject(i)
+            out[one.getString("name")] = one.getString("envelope").toByteArray(Charsets.UTF_8)
+        }
+        return out
+    }
+
+    /** A feed over a relay in a box on this machine, with a clock the test moves. */
+    private fun <T> withFeed(block: (MockWebServer, TodayFeed, () -> Unit) -> T): T {
+        val server = MockWebServer().also { it.start() }
+        val dir = Files.createTempDirectory("today-vectors").toFile()
+        var clock = 1_800_000_000_000L
+        try {
+            val feed = TodayFeed(server.url("/").toString().trimEnd('/'), dir, keys, now = { clock })
+            return block(server, feed) { clock += 2 * TodayFeed.INTERVAL_MS }
+        } finally {
+            server.shutdown()
+            dir.deleteRecursively()
+        }
+    }
+
+    private fun MockWebServer.serve(
+        bytes: ByteArray,
+        etag: String,
+    ) = enqueue(
+        MockResponse()
+            .setResponseCode(200)
+            .setHeader("Content-Type", "application/json")
+            .setHeader("ETag", etag)
+            .setBody(okio.Buffer().write(bytes)),
+    )
+
+    @Test
+    fun `an older file never replaces a newer one, through the feed`() {
+        val named = byName()
+        val made = { name: String -> (TodayFile.verify(named.getValue(name), keys) as TodayFile.Verdict.Good).bundle.made }
+        val steps = file.getJSONArray("sequence")
+        assertEquals(2, steps.length())
+        val wrong = mutableListOf<String>()
+        for (i in 0 until steps.length()) {
+            val step = steps.getJSONObject(i)
+            val held = named.getValue(step.getString("held"))
+            val then = named.getValue(step.getString("then"))
+            val shown = step.getString("shown")
+            val got =
+                withFeed { server, feed, later ->
+                    server.serve(held, TodayFeed.etagOf(held))
+                    feed.refresh()
+                    later()
+                    server.serve(then, TodayFeed.etagOf(then))
+                    feed.refresh()
+                    assertEquals(2, server.requestCount)
+                    feed.current().bundle?.made
+                }
+            if (got != made(shown)) wrong += "sequence '${step.getString("name")}': shows made $got, the file says '$shown' (made ${made(shown)})"
+        }
+        if (wrong.isNotEmpty()) fail(wrong.joinToString("\n"))
+    }
+
+    @Test
+    fun `the stored tag goes back only when it is the hash of the copy held`() {
+        val named = byName()
+        val rules = file.getJSONArray("ifNoneMatch")
+        assertEquals(4, rules.length())
+        val wrong = mutableListOf<String>()
+        for (i in 0 until rules.length()) {
+            val rule = rules.getJSONObject(i)
+            val stored = rule.getString("stored")
+            val send = rule.getBoolean("send")
+            val sent =
+                withFeed { server, feed, _ ->
+                    // The relay hands this tag over with a file the phone keeps,
+                    // or, with no copy to hold, with one it refuses.
+                    val held = if (rule.isNull("held")) null else named.getValue(rule.getString("held"))
+                    server.serve(held ?: "{}".toByteArray(), stored)
+                    feed.refresh()
+                    feed.request().header("If-None-Match")
+                }
+            if ((sent == stored) != send || (sent != null && sent != stored)) {
+                wrong += "ifNoneMatch '${rule.getString("name")}': sends ${sent ?: "nothing"}, the file says send=$send"
+            }
+        }
+        if (wrong.isNotEmpty()) fail(wrong.joinToString("\n"))
+    }
+}