Refactor txid wire encoding and repair library

Share the txid-and-text payload builder between hex and reply, extract the
repair store loop from repairTxidEncoding to cut CRAP from 13 to 5, correct
the poll-services property test to the little-endian wire order, and add
property tests for wire round trips and repair idempotence/conservation.

By refactorer.

psf-memo-client/src/services/hex.js

@@ -35,9 +35,9 @@ function txidToWireBytes (txid, label = 'Value') {
 
 // Build the raw OP_RETURN payload for a txid-referencing Memo action: the
 // given 32-byte txid in little-endian wire order followed by a UTF-8 encoded
-// value.
-function buildTxidTextPayload (txid, text) {
-  const txidBytes = txidToWireBytes(txid, 'Poll txid')
+// value. The label customizes the invalid-txid error message.
+function buildTxidTextPayload (txid, text, label = 'Poll txid') {
+  const txidBytes = txidToWireBytes(txid, label)
   const textBytes = new TextEncoder().encode(text)
   const raw = new Uint8Array(txidBytes.length + textBytes.length)
   raw.set(txidBytes, 0)

psf-memo-client/src/services/memo-reply.js

@@ -18,7 +18,7 @@
 
 const MemoAction = require('./memo-action')
 const { byteLength } = require('./utf8')
-const { txidToWireBytes } = require('./hex')
+const { buildTxidTextPayload } = require('./hex')
 
 const MEMO_REPLY_PREFIX = '6d03'
 const MAX_REPLY_BYTES = 184
@@ -57,7 +57,7 @@ class MemoReply extends MemoAction {
     await this.wallet.getUtxos()
 
     // Build the raw payload: parent txid bytes followed by UTF-8 message bytes.
-    const raw = buildReplyPayload(parentTxid, message)
+    const raw = buildTxidTextPayload(parentTxid, message, 'Parent txid')
     const txid = await this.wallet.sendOpReturn(raw, this.prefix)
 
     // Reflect the result on the injected thread once broadcast succeeds.
@@ -79,17 +79,6 @@ class MemoReply extends MemoAction {
   }
 }
 
-// Build the raw OP_RETURN message payload for a reply.
-// The protocol wire format is: <parent txid 32 bytes><reply text UTF-8 bytes>.
-function buildReplyPayload (parentTxid, message) {
-  const parentBytes = txidToWireBytes(parentTxid, 'Parent txid')
-  const textBytes = new TextEncoder().encode(message)
-  const raw = new Uint8Array(parentBytes.length + textBytes.length)
-  raw.set(parentBytes, 0)
-  raw.set(textBytes, parentBytes.length)
-  return raw
-}
-
 MemoReply.MEMO_REPLY_PREFIX = MEMO_REPLY_PREFIX
 MemoReply.MAX_REPLY_BYTES = MAX_REPLY_BYTES
 

psf-memo-client/test/property/poll-services.property.test.js

@@ -67,12 +67,11 @@ test('buildTxidTextPayload round-trips the canonical Memo wire format', async ()
     ({ txid, text }) => {
       const bytes = buildTxidTextPayload(txid, text)
       if (bytes.length !== 32 + byteLength(text)) return false
-      // The payload carries the txid's literal 32 bytes in order, followed by
-      // the UTF-8 bytes of the value.
-      const expectedTxidBytes = hexToBytes(txid, 32, 'Poll txid')
-      for (let i = 0; i < 32; i++) {
-        if (bytes[i] !== expectedTxidBytes[i]) return false
-      }
+      // The payload carries the txid in little-endian wire order, followed by
+      // the UTF-8 bytes of the value. Reversing the wire bytes must recover
+      // the 64-character display txid.
+      const wire = Buffer.from(bytes.slice(0, 32))
+      if (wire.reverse().toString('hex') !== txid) return false
       const storedText = Buffer.from(bytes.slice(32)).toString('utf8')
       return storedText === text
     },

psf-memo-client/test/property/txid-wire-encoding.property.test.js

@@ -0,0 +1,108 @@
+/*
+  Property tests for Memo txid wire encoding.
+
+  Unit tests pin the wire bytes of a few fixed txids. These properties pin the
+  encoding invariants over broad random inputs:
+
+    - Round trip: reversing the wire bytes recovers the display bytes, and
+      reversing twice is the identity.
+    - Wire order: the encoded bytes are exactly the reverse of the display
+      txid's bytes.
+    - Payload shape: a txid-and-text payload starts with the wire txid and
+      ends with the UTF-8 text, with no bytes added or dropped.
+    - Determinism: the same txid always encodes to the same bytes.
+*/
+
+'use strict'
+
+const test = require('node:test')
+const assert = require('node:assert/strict')
+const { seededRandom, forAll, intGen } = require('./harness')
+const { txidToWireBytes, buildTxidTextPayload } = require('../../src/services/hex')
+
+const HEX_CHARS = '0123456789abcdef'
+
+function randomTxid (rng) {
+  let out = ''
+  for (let i = 0; i < 64; i++) {
+    out += HEX_CHARS[Math.floor(rng() * HEX_CHARS.length)]
+  }
+  return out
+}
+
+function randomText (rng) {
+  const alphabet = 'abc XYZ!\u00e9\u4e2d\ud83d\ude00'
+  let out = ''
+  const length = intGen(rng, 0, 24)()
+  for (let i = 0; i < length; i++) {
+    out += alphabet[Math.floor(rng() * alphabet.length)]
+  }
+  return out
+}
+
+test('txid wire bytes are the byte reverse of the display txid', async () => {
+  const rng = seededRandom(20260916)
+
+  await forAll(
+    () => randomTxid(rng),
+    (txid) => {
+      const wire = Buffer.from(txidToWireBytes(txid)).toString('hex')
+      const expected = Buffer.from(txid, 'hex').reverse().toString('hex')
+      return wire === expected
+    },
+    { label: 'txidToWireBytes byte order' }
+  )
+})
+
+test('reversing wire bytes twice recovers the display txid', async () => {
+  const rng = seededRandom(20260917)
+
+  await forAll(
+    () => randomTxid(rng),
+    (txid) => {
+      const bytes = txidToWireBytes(txid)
+      return Buffer.from(Buffer.from(bytes).reverse()).toString('hex') === txid
+    },
+    { label: 'txidToWireBytes round trip' }
+  )
+})
+
+test('txid encoding is deterministic', async () => {
+  const rng = seededRandom(20260918)
+
+  await forAll(
+    () => randomTxid(rng),
+    (txid) => {
+      const first = Buffer.from(txidToWireBytes(txid)).toString('hex')
+      const second = Buffer.from(txidToWireBytes(txid)).toString('hex')
+      return first === second
+    },
+    { label: 'txidToWireBytes determinism' }
+  )
+})
+
+test('payload embeds the wire txid followed by the UTF-8 text', async () => {
+  const rng = seededRandom(20260919)
+
+  await forAll(
+    () => ({ txid: randomTxid(rng), text: randomText(rng) }),
+    ({ txid, text }) => {
+      const raw = buildTxidTextPayload(txid, text)
+      const buf = Buffer.from(raw)
+      const wire = Buffer.from(txidToWireBytes(txid)).toString('hex')
+      const expectedText = Buffer.from(text, 'utf8')
+
+      if (buf.length !== 32 + expectedText.length) return false
+      if (buf.subarray(0, 32).toString('hex') !== wire) return false
+      return buf.subarray(32).equals(expectedText)
+    },
+    { label: 'buildTxidTextPayload shape' }
+  )
+})
+
+test('a reply payload rejects an invalid txid with the parent label', () => {
+  assert.throws(
+    () => buildTxidTextPayload('not-a-txid', 'hi', 'Parent txid'),
+    /Parent txid must be a 64-character hex string/
+  )
+})

psf-memo-client/test/unit/memo-like.test.js

@@ -60,3 +60,118 @@ test('like reflects the post txid in display order on the feed store', async ()
   assert.equal(added.length, 1)
   assert.equal(added[0].postTxid, POST_TXID)
 })
+
+test('like rejects a caller without a wallet', async () => {
+  const memoLike = new MemoLike()
+
+  await assert.rejects(() => memoLike.like(POST_TXID), /requires a wallet/)
+})
+
+test('like rejects an invalid post txid before broadcasting', async () => {
+  const wallet = makeWallet()
+  const memoLike = new MemoLike({ wallet })
+
+  await assert.rejects(
+    () => memoLike.like('not-a-txid'),
+    (err) => err.code === 'like_validation'
+  )
+  assert.equal(wallet.broadcasts.length, 0)
+})
+
+test('like rejects a balance below the dust limit', async () => {
+  const wallet = makeWallet()
+  wallet.utxos = [{ txid: 'utxo', value: 100 }]
+  const memoLike = new MemoLike({ wallet })
+
+  await assert.rejects(
+    () => memoLike.like(POST_TXID),
+    (err) => err.code === 'like_empty_balance'
+  )
+})
+
+test('like rejects a tip that exceeds the spendable balance', async () => {
+  const wallet = makeWallet()
+  wallet.utxos = [{ txid: 'utxo', value: 3000 }]
+  const memoLike = new MemoLike({ wallet })
+
+  await assert.rejects(
+    () => memoLike.like(POST_TXID, 4000, MY_ADDRESS),
+    (err) => err.code === 'like_balance'
+  )
+})
+
+test('like requires an author address when a tip is present', async () => {
+  const wallet = makeWallet()
+  const memoLike = new MemoLike({ wallet })
+
+  await assert.rejects(
+    () => memoLike.like(POST_TXID, 1000),
+    (err) => err.code === 'like_validation'
+  )
+})
+
+test('_validateTipAmount rejects a non-integer or negative tip', () => {
+  const memoLike = new MemoLike()
+
+  assert.throws(() => memoLike._validateTipAmount(1.5), (err) => err.code === 'like_validation')
+  assert.throws(() => memoLike._validateTipAmount(-1), (err) => err.code === 'like_validation')
+})
+
+test('_validateTipAmount rejects a tip below the dust limit', () => {
+  const memoLike = new MemoLike()
+
+  assert.throws(() => memoLike._validateTipAmount(1), (err) => err.code === 'like_dust')
+})
+
+test('_validateTipAmount rejects a tip above the maximum', () => {
+  const memoLike = new MemoLike()
+
+  assert.throws(
+    () => memoLike._validateTipAmount(MemoLike.MAX_TIP_SATS + 1),
+    (err) => err.code === 'like_maximum'
+  )
+})
+
+test('_validateTipAmount accepts zero and a valid tip', () => {
+  const memoLike = new MemoLike()
+
+  assert.equal(memoLike._validateTipAmount(0), undefined)
+  assert.equal(memoLike._validateTipAmount(1000), undefined)
+})
+
+test('getSpendableSats sums the utxoStore bchUtxos shape', () => {
+  const wallet = {
+    utxos: { utxoStore: { bchUtxos: [{ satoshis: 1000 }, { amount: 500 }] } }
+  }
+  const memoLike = new MemoLike({ wallet })
+
+  assert.equal(memoLike.getSpendableSats(), 1500)
+})
+
+test('getSpendableSats is zero without a wallet', () => {
+  assert.equal(new MemoLike().getSpendableSats(), 0)
+})
+
+test('like includes a tip output and reflects the tip on the feed', async () => {
+  const wallet = makeWallet()
+  const added = []
+  const feed = {
+    addLike (like) {
+      added.push(like)
+    },
+    posts: [{ txid: POST_TXID, likeCount: 2 }]
+  }
+  const memoLike = new MemoLike({ wallet, feed })
+
+  await memoLike.like(POST_TXID, 1000, MY_ADDRESS)
+
+  assert.deepEqual(wallet.broadcasts[0].bchOutput, [{ address: MY_ADDRESS, amountSat: 1000 }])
+  assert.equal(added[0].tipSats, 1000)
+  assert.equal(feed.posts[0].likeCount, 3)
+})
+
+test('_buildTipOutput omits the output for a zero tip', () => {
+  const memoLike = new MemoLike()
+
+  assert.deepEqual(memoLike._buildTipOutput(0, MY_ADDRESS), [])
+})

psf-memo-db/src/lib/repair-txid-encoding.js

@@ -43,50 +43,70 @@ export async function correctReference (targetDb, reference) {
   return reference
 }
 
+// Repair one referencing store in place. Every record whose reference can be
+// corrected is rewritten; an optional secondary index rebuilds its entry for
+// each corrected record. Returns the number of records corrected.
+async function repairStore ({ sourceDb, referenceField, targetDb, index }) {
+  let correctedCount = 0
+
+  for await (const [recordTxid, record] of sourceDb.iterator()) {
+    const reference = record[referenceField]
+    if (!reference) continue
+
+    const corrected = await correctReference(targetDb, reference)
+    if (corrected === reference) continue
+
+    await sourceDb.put(recordTxid, { ...record, [referenceField]: corrected })
+
+    if (index) {
+      await index.db.del(index.key(reference, recordTxid))
+      await index.db.put(index.key(corrected, recordTxid), index.value(record, corrected, recordTxid))
+    }
+
+    correctedCount++
+  }
+
+  return correctedCount
+}
+
+// A secondary index keyed as <target txid>:<record txid>; both the postLikes
+// and postChildren indexes use this shape.
+function txidIndex (db, value) {
+  return {
+    db,
+    key: (targetTxid, recordTxid) => `${targetTxid}:${recordTxid}`,
+    value
+  }
+}
+
 // Repair likes, replies, poll options, and poll votes in place. Returns a
 // summary of how many records of each kind were corrected.
 export async function repairTxidEncoding (level) {
-  const summary = { likes: 0, replies: 0, pollOptions: 0, pollVotes: 0 }
+  const likes = await repairStore({
+    sourceDb: level.likesDb,
+    referenceField: 'postTxid',
+    targetDb: level.postsDb,
+    index: txidIndex(level.postLikesDb, (record, postTxid, likeTxid) => ({ postTxid, txid: likeTxid }))
+  })
 
-  for await (const [likeTxid, like] of level.likesDb.iterator()) {
-    if (!like.postTxid) continue
-    const corrected = await correctReference(level.postsDb, like.postTxid)
-    if (corrected === like.postTxid) continue
+  const replies = await repairStore({
+    sourceDb: level.postParentsDb,
+    referenceField: 'parentTxid',
+    targetDb: level.postsDb,
+    index: txidIndex(level.postChildrenDb, (record, parentTxid) => ({ ...record, parentTxid }))
+  })
 
-    await level.likesDb.put(likeTxid, { ...like, postTxid: corrected })
-    await level.postLikesDb.del(`${like.postTxid}:${likeTxid}`)
-    await level.postLikesDb.put(`${corrected}:${likeTxid}`, { postTxid: corrected, txid: likeTxid })
-    summary.likes++
-  }
-
-  for await (const [replyTxid, reply] of level.postParentsDb.iterator()) {
-    if (!reply.parentTxid) continue
-    const corrected = await correctReference(level.postsDb, reply.parentTxid)
-    if (corrected === reply.parentTxid) continue
-
-    await level.postParentsDb.put(replyTxid, { ...reply, parentTxid: corrected })
-    await level.postChildrenDb.del(`${reply.parentTxid}:${replyTxid}`)
-    await level.postChildrenDb.put(`${corrected}:${replyTxid}`, { ...reply, parentTxid: corrected })
-    summary.replies++
-  }
-
-  for await (const [optionTxid, option] of level.pollOptionsDb.iterator()) {
-    if (!option.pollTxid) continue
-    const corrected = await correctReference(level.pollsDb, option.pollTxid)
-    if (corrected === option.pollTxid) continue
-
-    await level.pollOptionsDb.put(optionTxid, { ...option, pollTxid: corrected })
-    summary.pollOptions++
-  }
-
-  for await (const [voteTxid, vote] of level.pollVotesDb.iterator()) {
-    if (!vote.pollTxid) continue
-    const corrected = await correctReference(level.pollsDb, vote.pollTxid)
-    if (corrected === vote.pollTxid) continue
-
-    await level.pollVotesDb.put(voteTxid, { ...vote, pollTxid: corrected })
-    summary.pollVotes++
-  }
-
-  return summary
+  const pollOptions = await repairStore({
+    sourceDb: level.pollOptionsDb,
+    referenceField: 'pollTxid',
+    targetDb: level.pollsDb
+  })
+
+  const pollVotes = await repairStore({
+    sourceDb: level.pollVotesDb,
+    referenceField: 'pollTxid',
+    targetDb: level.pollsDb
+  })
+
+  return { likes, replies, pollOptions, pollVotes }
 }

psf-memo-db/test/property/repair-txid-encoding.property.test.js

@@ -0,0 +1,257 @@
+/*
+  Property tests for the txid encoding repair library.
+
+  Unit tests probe the repair at a fixed fixture. These properties pin the
+  invariants over broad random inputs:
+
+    - Selection: correctReference prefers the stored reference when its target
+      exists, falls back to the reversed reference when only that target
+      exists, and leaves an unknown reference unchanged.
+    - Involution: reversing a txid twice returns the original display txid.
+    - Idempotence: a second repair run changes nothing.
+    - Conservation: repair never adds or drops primary records.
+    - Resolution: after repair every reference points at an existing target
+      when either byte order had one.
+*/
+
+import test from 'node:test'
+
+import { seededRandom, forAll, intGen, txidGen } from './harness.js'
+import {
+  reverseTxid,
+  correctReference,
+  repairTxidEncoding
+} from '../../src/lib/repair-txid-encoding.js'
+
+const rng = seededRandom(20260916)
+
+class FakeDb {
+  constructor () {
+    this.map = new Map()
+  }
+
+  async get (key) {
+    if (!this.map.has(key)) {
+      const err = new Error(`not found: ${key}`)
+      err.notFound = true
+      throw err
+    }
+    return this.map.get(key)
+  }
+
+  async put (key, value) {
+    this.map.set(key, value)
+  }
+
+  async del (key) {
+    this.map.delete(key)
+  }
+
+  async * iterator () {
+    for (const [key, value] of this.map) {
+      yield [key, value]
+    }
+  }
+}
+
+function makeLevel () {
+  return {
+    postsDb: new FakeDb(),
+    pollsDb: new FakeDb(),
+    likesDb: new FakeDb(),
+    postLikesDb: new FakeDb(),
+    postParentsDb: new FakeDb(),
+    postChildrenDb: new FakeDb(),
+    pollOptionsDb: new FakeDb(),
+    pollVotesDb: new FakeDb()
+  }
+}
+
+// Snapshot every store as a stable string so a second run can be compared.
+function snapshot (level) {
+  const stores = {}
+  for (const [name, db] of Object.entries(level)) {
+    stores[name] = [...db.map.entries()].sort(([a], [b]) => a.localeCompare(b))
+  }
+  return JSON.stringify(stores)
+}
+
+// A reference that is the display target, its reverse, or an unrelated txid.
+function referenceTo (rng, targets, unknown) {
+  if (targets.length === 0) return unknown
+  const roll = rng()
+  const target = targets[intGen(rng, 0, targets.length - 1)()]
+  if (roll < 1 / 3) return target
+  if (roll < 2 / 3) return reverseTxid(target)
+  return unknown
+}
+
+// Build a random level with display posts/polls and a mix of correct,
+// reversed, and unknown references in each primary store. FakeDb.put mutates
+// synchronously, so this builder is synchronous for the property harness.
+function buildFixture () {
+  const level = makeLevel()
+  const postTxids = []
+  const pollTxids = []
+
+  const postCount = intGen(rng, 0, 5)()
+  for (let i = 0; i < postCount; i++) {
+    const txid = txidGen(rng)
+    postTxids.push(txid)
+    level.postsDb.put(txid, { addr: `addr-${i}`, text: 'post', blockHeight: i })
+  }
+
+  const pollCount = intGen(rng, 0, 4)()
+  for (let i = 0; i < pollCount; i++) {
+    const txid = txidGen(rng)
+    pollTxids.push(txid)
+    level.pollsDb.put(txid, { question: 'q', pollType: 1, optionCount: 2, blockHeight: i })
+  }
+
+  const likeCount = intGen(rng, 0, 6)()
+  for (let i = 0; i < likeCount; i++) {
+    const likeTxid = `like-${i}`
+    const postTxid = referenceTo(rng, postTxids, txidGen(rng))
+    level.likesDb.put(likeTxid, { postTxid, addr: 'addr', blockHeight: i })
+    level.postLikesDb.put(`${postTxid}:${likeTxid}`, { postTxid, txid: likeTxid })
+  }
+
+  const replyCount = intGen(rng, 0, 6)()
+  for (let i = 0; i < replyCount; i++) {
+    const replyTxid = `reply-${i}`
+    const parentTxid = referenceTo(rng, postTxids, txidGen(rng))
+    level.postParentsDb.put(replyTxid, { parentTxid, childTxid: replyTxid, blockHeight: i })
+    level.postChildrenDb.put(`${parentTxid}:${replyTxid}`, { parentTxid, childTxid: replyTxid })
+  }
+
+  const optionCount = intGen(rng, 0, 5)()
+  for (let i = 0; i < optionCount; i++) {
+    const pollTxid = referenceTo(rng, pollTxids, txidGen(rng))
+    level.pollOptionsDb.put(`option-${i}`, { pollTxid, option: `opt-${i}`, blockHeight: i })
+  }
+
+  const voteCount = intGen(rng, 0, 5)()
+  for (let i = 0; i < voteCount; i++) {
+    const pollTxid = referenceTo(rng, pollTxids, txidGen(rng))
+    level.pollVotesDb.put(`vote-${i}`, { pollTxid, comment: `vote-${i}`, blockHeight: i })
+  }
+
+  return { level, postTxids, pollTxids }
+}
+
+function primaryCounts (level) {
+  return {
+    likes: level.likesDb.map.size,
+    replies: level.postParentsDb.map.size,
+    pollOptions: level.pollOptionsDb.map.size,
+    pollVotes: level.pollVotesDb.map.size
+  }
+}
+
+// True when every reference in a store is either a known target or unknown in
+// both byte orders. Repair must not leave a resolvable reference unresolved.
+function allResolvableOrUnknown (db, targetDb, field) {
+  for (const record of db.map.values()) {
+    const reference = record[field]
+    if (targetDb.map.has(reference)) continue
+    if (targetDb.map.has(reverseTxid(reference))) return false
+  }
+  return true
+}
+
+test('reverseTxid is an involution on valid txids', async () => {
+  await forAll(
+    () => txidGen(rng),
+    (txid) => reverseTxid(reverseTxid(txid)) === txid,
+    { label: 'reverseTxid involution' }
+  )
+})
+
+test('correctReference selects an existing target in either byte order', async () => {
+  await forAll(
+    () => txidGen(rng),
+    async (txid) => {
+      const display = makeLevel()
+      await display.postsDb.put(txid, {})
+      if (await correctReference(display.postsDb, txid) !== txid) return false
+
+      const reversed = makeLevel()
+      await reversed.postsDb.put(txid, {})
+      if (await correctReference(reversed.postsDb, reverseTxid(txid)) !== txid) return false
+
+      const unknown = makeLevel()
+      const missing = txid
+      if (await correctReference(unknown.postsDb, missing) !== missing) return false
+
+      return true
+    },
+    { label: 'correctReference selection' }
+  )
+})
+
+test('repairTxidEncoding is idempotent and conserves records', async () => {
+  await forAll(
+    () => buildFixture(),
+    async ({ level }) => {
+      const before = primaryCounts(level)
+
+      await repairTxidEncoding(level)
+      const afterFirst = snapshot(level)
+
+      await repairTxidEncoding(level)
+      if (snapshot(level) !== afterFirst) return false
+
+      const after = primaryCounts(level)
+      return JSON.stringify(before) === JSON.stringify(after)
+    },
+    { label: 'repairTxidEncoding idempotence' }
+  )
+})
+
+test('repairTxidEncoding resolves every resolvable reference', async () => {
+  await forAll(
+    () => buildFixture(),
+    async ({ level }) => {
+      await repairTxidEncoding(level)
+
+      return allResolvableOrUnknown(level.likesDb, level.postsDb, 'postTxid') &&
+        allResolvableOrUnknown(level.postParentsDb, level.postsDb, 'parentTxid') &&
+        allResolvableOrUnknown(level.pollOptionsDb, level.pollsDb, 'pollTxid') &&
+        allResolvableOrUnknown(level.pollVotesDb, level.pollsDb, 'pollTxid')
+    },
+    { label: 'repairTxidEncoding resolution' }
+  )
+})
+
+test('repairTxidEncoding rebuilds the secondary indexes for corrected records', async () => {
+  await forAll(
+    () => buildFixture(),
+    async ({ level }) => {
+      await repairTxidEncoding(level)
+
+      for (const [likeTxid, like] of level.likesDb.map) {
+        if (!level.postLikesDb.map.has(`${like.postTxid}:${likeTxid}`)) return false
+      }
+      for (const [replyTxid, reply] of level.postParentsDb.map) {
+        if (!level.postChildrenDb.map.has(`${reply.parentTxid}:${replyTxid}`)) return false
+      }
+      return true
+    },
+    { label: 'repairTxidEncoding index rebuild' }
+  )
+})
+
+test('an unknown reference is left unchanged by repair', async () => {
+  await forAll(
+    () => txidGen(rng),
+    async (unknown) => {
+      const level = makeLevel()
+      await level.likesDb.put('like-unknown', { postTxid: unknown, addr: 'addr' })
+
+      await repairTxidEncoding(level)
+
+      return (await level.likesDb.get('like-unknown')).postTxid === unknown
+    },
+    { label: 'repairTxidEncoding unknown reference' }
+  )
+})