From 55c1ccdc24ec52f7a1eaeccf41573fb19cad874f Mon Sep 17 00:00:00 2001
From: Richard Gibson <richard.gibson@gmail.com>
Date: Fri, 6 Sep 2024 13:42:31 -0400
Subject: [PATCH 1/8] style(swing-store): Use consistent transcriptStore
 variable names, ordering, and values

---
 packages/swing-store/src/transcriptStore.js | 34 +++++++++++----------
 1 file changed, 18 insertions(+), 16 deletions(-)

diff --git a/packages/swing-store/src/transcriptStore.js b/packages/swing-store/src/transcriptStore.js
index 4a7ae9c47d6..d5d9a1bb1e2 100644
--- a/packages/swing-store/src/transcriptStore.js
+++ b/packages/swing-store/src/transcriptStore.js
@@ -219,10 +219,12 @@ export function makeTranscriptStore(
    */
   function initTranscript(vatID) {
     ensureTxn();
-    const initialIncarnation = 0;
-    sqlWriteSpan.run(vatID, 0, 0, initialHash, 1, initialIncarnation);
-    const newRec = spanRec(vatID, 0, 0, initialHash, true, 0);
-    noteExport(spanMetadataKey(newRec), JSON.stringify(newRec));
+    const pos = 0;
+    const isCurrent = 1;
+    const incarnation = 0;
+    sqlWriteSpan.run(vatID, pos, pos, initialHash, isCurrent, incarnation);
+    const rec = spanRec(vatID, pos, pos, initialHash, isCurrent, incarnation);
+    noteExport(spanMetadataKey(rec), JSON.stringify(rec));
   }
 
   const sqlGetCurrentSpanBounds = db.prepare(`
@@ -257,13 +259,13 @@ export function makeTranscriptStore(
 
   function doSpanRollover(vatID, isNewIncarnation) {
     ensureTxn();
-    const { hash, startPos, endPos, incarnation } = getCurrentSpanBounds(vatID);
-    const rec = spanRec(vatID, startPos, endPos, hash, false, incarnation);
+    const { startPos, endPos, hash, incarnation } = getCurrentSpanBounds(vatID);
+    const oldRec = spanRec(vatID, startPos, endPos, hash, false, incarnation);
 
     // add a new record for the now-old span
-    noteExport(spanMetadataKey(rec), JSON.stringify(rec));
+    noteExport(spanMetadataKey(oldRec), JSON.stringify(oldRec));
 
-    // and change its DB row to isCurrent=0
+    // and change its DB row to isCurrent=null
     sqlEndCurrentSpan.run(vatID);
 
     // create a new (empty) row, with isCurrent=1
@@ -271,7 +273,7 @@ export function makeTranscriptStore(
     sqlWriteSpan.run(vatID, endPos, endPos, initialHash, 1, incarnationToUse);
 
     // overwrite the transcript.${vatID}.current record with new span
-    const newRec = spanRec(
+    const rec = spanRec(
       vatID,
       endPos,
       endPos,
@@ -279,7 +281,7 @@ export function makeTranscriptStore(
       true,
       incarnationToUse,
     );
-    noteExport(spanMetadataKey(newRec), JSON.stringify(newRec));
+    noteExport(spanMetadataKey(rec), JSON.stringify(rec));
 
     if (!keepTranscripts) {
       // Delete items of the previously-current span.
@@ -360,8 +362,8 @@ export function makeTranscriptStore(
   `);
 
   /**
-   * Prepare for vat deletion by marking the isCurrent span as not
-   * current. Idempotent.
+   * Prepare for vat deletion by marking the isCurrent=1 span as not current.
+   * Idempotent.
    *
    * @param {string} vatID  The vat being terminated/deleted.
    */
@@ -373,10 +375,10 @@ export function makeTranscriptStore(
     if (bounds) {
       // add a new record for the now-old span
       const { startPos, endPos, hash, incarnation } = bounds;
-      const rec = spanRec(vatID, startPos, endPos, hash, false, incarnation);
-      noteExport(spanMetadataKey(rec), JSON.stringify(rec));
+      const oldRec = spanRec(vatID, startPos, endPos, hash, false, incarnation);
+      noteExport(spanMetadataKey(oldRec), JSON.stringify(oldRec));
 
-      // and change its DB row to isCurrent=0
+      // and change its DB row to isCurrent=null
       sqlEndCurrentSpan.run(vatID);
 
       // remove the transcript.${vatID}.current record
@@ -542,7 +544,7 @@ export function makeTranscriptStore(
         }
       }
     } else if (artifactMode === 'archival') {
-      // every span for all vatIDs that have an isCurrent span (to
+      // every span for all vatIDs that have an isCurrent=1 span (to
       // ignore terminated/partially-deleted vats)
       const vatIDs = new Set();
       for (const { vatID } of sqlGetCurrentSpanMetadata.iterate()) {

From e67be983ada7c4f583f6c0c23700b19311d2adc2 Mon Sep 17 00:00:00 2001
From: Richard Gibson <richard.gibson@gmail.com>
Date: Fri, 6 Sep 2024 16:23:38 -0400
Subject: [PATCH 2/8] test(swing-store): Refactor for better failure detail

---
 packages/internal/tools/ava-assertions.js  | 26 ++++++++++
 packages/swing-store/test/deletion.test.js | 56 +++++++++++-----------
 2 files changed, 53 insertions(+), 29 deletions(-)
 create mode 100644 packages/internal/tools/ava-assertions.js

diff --git a/packages/internal/tools/ava-assertions.js b/packages/internal/tools/ava-assertions.js
new file mode 100644
index 00000000000..d53b36fbf57
--- /dev/null
+++ b/packages/internal/tools/ava-assertions.js
@@ -0,0 +1,26 @@
+/**
+ * Assert that the contents of `array` are
+ * [like]{@link https://github.com/avajs/ava/blob/main/docs/03-assertions.md#likeactual-selector-message}
+ * those of `expected`, including having matching lengths, with pretty diffs in
+ * case of mismatch.
+ *
+ * @param {import('ava').ExecutionContext} t
+ * @param {unknown[]} array
+ * @param {unknown[]} expected
+ * @param {string} [message]
+ */
+export const arrayIsLike = (t, array, expected, message) => {
+  const actualLength = array.length;
+  const expectedLength = expected.length;
+  const actualExcess = actualLength - expectedLength;
+  const comparable =
+    actualExcess > 0
+      ? [...expected, ...Array.from({ length: actualExcess })]
+      : expected;
+  t.like(array, comparable, message);
+
+  if (actualLength === expectedLength) return;
+
+  const extended = [...array, ...Array.from({ length: -actualExcess })];
+  t.deepEqual(extended, array, message);
+};
diff --git a/packages/swing-store/test/deletion.test.js b/packages/swing-store/test/deletion.test.js
index e749fe92ba7..1c482a786cb 100644
--- a/packages/swing-store/test/deletion.test.js
+++ b/packages/swing-store/test/deletion.test.js
@@ -4,6 +4,7 @@ import path from 'path';
 
 import { Buffer } from 'node:buffer';
 import sqlite3 from 'better-sqlite3';
+import { arrayIsLike } from '@agoric/internal/tools/ava-assertions.js';
 import { tmpDir } from './util.js';
 import { initSwingStore } from '../src/swingStore.js';
 import { makeSwingStoreExporter } from '../src/exporter.js';
@@ -50,32 +51,31 @@ test('delete snapshots with export callback', async t => {
 
   await commit();
 
-  t.is(exportLog.length, 4);
-  t.is(exportLog[0][0], 'snapshot.v1.10');
-  t.is(exportLog[1][0], 'snapshot.v1.11');
-  t.is(exportLog[2][0], 'snapshot.v1.12');
-  t.is(exportLog[3][0], 'snapshot.v1.current');
   const hash = JSON.parse(exportLog[0][1]).hash;
+  arrayIsLike(t, exportLog.splice(0), [
+    ['snapshot.v1.10'],
+    ['snapshot.v1.11'],
+    ['snapshot.v1.12'],
+    ['snapshot.v1.current'],
+  ]);
   t.deepEqual(exportData, {
     'snapshot.v1.10': JSON.stringify({ vatID, snapPos: 10, hash, inUse: 0 }),
     'snapshot.v1.11': JSON.stringify({ vatID, snapPos: 11, hash, inUse: 0 }),
     'snapshot.v1.12': JSON.stringify({ vatID, snapPos: 12, hash, inUse: 1 }),
     'snapshot.v1.current': 'snapshot.v1.12',
   });
-  exportLog.length = 0;
 
   // in a previous version, deleteVatSnapshots caused overlapping SQL
   // queries, and failed
   snapStore.deleteVatSnapshots(vatID);
   await commit();
 
-  t.deepEqual(exportLog, [
+  t.deepEqual(exportLog.splice(0), [
     ['snapshot.v1.10', null],
     ['snapshot.v1.11', null],
     ['snapshot.v1.12', null],
     ['snapshot.v1.current', null],
   ]);
-  exportLog.length = 0;
   t.deepEqual(exportData, {});
 });
 
@@ -104,22 +104,20 @@ test('delete transcripts with export callback', async t => {
 
   await commit();
 
-  t.is(exportLog.length, 2);
-  t.is(exportLog[0][0], 'transcript.v1.0');
-  t.is(exportLog[1][0], 'transcript.v1.current');
-  exportLog.length = 0;
+  arrayIsLike(t, exportLog.splice(0), [
+    ['transcript.v1.0'],
+    ['transcript.v1.current'],
+  ]);
 
   // in a previous version, deleteVatTranscripts caused overlapping SQL
   // queries, and failed
   transcriptStore.deleteVatTranscripts('v1');
   await commit();
 
-  t.deepEqual(exportLog, [
+  t.deepEqual(exportLog.splice(0), [
     ['transcript.v1.0', null],
     ['transcript.v1.current', null],
   ]);
-
-  exportLog.length = 0;
 });
 
 const getExport = async (dbDir, artifactMode) => {
@@ -145,13 +143,13 @@ const reImport = async (t, dbDir, artifactMode) => {
   return sqlite3(path.join(dbDir2, 'swingstore.sqlite'));
 };
 
-const compareNoHash = (t, obj1, obj2) => {
-  const o1 = {};
-  for (const [key, value] of Object.entries(obj1)) {
+const compareNoHash = (t, actual, expected, message) => {
+  const stripped = {};
+  for (const [key, value] of Object.entries(actual)) {
     const { hash: _, ...data } = JSON.parse(value);
-    o1[key] = data;
+    stripped[key] = data;
   }
-  return t.deepEqual(o1, obj2);
+  return t.deepEqual(stripped, expected, message);
 };
 
 const setupTranscript = async t => {
@@ -213,12 +211,12 @@ test('slow deletion of transcripts', async t => {
     vatID,
   } = await setupTranscript(t);
 
-  t.is(exportLog.length, 4);
-  t.is(exportLog[0][0], 'transcript.v1.0');
-  t.is(exportLog[1][0], 'transcript.v1.2');
-  t.is(exportLog[2][0], 'transcript.v1.4');
-  t.is(exportLog[3][0], 'transcript.v1.current');
-  exportLog.length = 0;
+  arrayIsLike(t, exportLog.splice(0), [
+    ['transcript.v1.0'],
+    ['transcript.v1.2'],
+    ['transcript.v1.4'],
+    ['transcript.v1.current'],
+  ]);
   const t0 = { vatID, startPos: 0, endPos: 2, isCurrent: 0, incarnation: 0 };
   const t2 = { vatID, startPos: 2, endPos: 4, isCurrent: 0, incarnation: 0 };
   const t4 = { vatID, startPos: 4, endPos: 6, isCurrent: 0, incarnation: 1 };
@@ -288,7 +286,7 @@ test('slow deletion of transcripts', async t => {
     // stopUsingTranscript is idempotent
     transcriptStore.stopUsingTranscript(vatID);
     await commit();
-    t.is(exportLog.length, 0);
+    t.deepEqual(exportLog, []);
   }
 
   // All exports (debug and non-debug) in this "terminated but not
@@ -417,7 +415,7 @@ test('slow deletion of transcripts', async t => {
     t.true(dc.done);
     t.is(dc.cleanups, 0);
     await commit();
-    t.is(exportLog.length, 0);
+    t.deepEqual(exportLog, []);
   }
 });
 
@@ -556,7 +554,7 @@ test('slow deletion of snapshots', async t => {
     // stopUsingLastSnapshot is idempotent
     snapStore.stopUsingLastSnapshot(vatID);
     await commit();
-    t.is(exportLog.length, 0);
+    t.deepEqual(exportLog, []);
   }
 
   // first deletion

From 5b41def65e3a26f5269dd55c98f8c2ff173087d5 Mon Sep 17 00:00:00 2001
From: Richard Gibson <richard.gibson@gmail.com>
Date: Fri, 6 Sep 2024 16:23:38 -0400
Subject: [PATCH 3/8] test(swing-store): DRY out deletion.test.js expectations

---
 packages/swing-store/test/deletion.test.js | 152 ++++++++++-----------
 1 file changed, 70 insertions(+), 82 deletions(-)

diff --git a/packages/swing-store/test/deletion.test.js b/packages/swing-store/test/deletion.test.js
index 1c482a786cb..37917cde345 100644
--- a/packages/swing-store/test/deletion.test.js
+++ b/packages/swing-store/test/deletion.test.js
@@ -220,15 +220,27 @@ test('slow deletion of transcripts', async t => {
   const t0 = { vatID, startPos: 0, endPos: 2, isCurrent: 0, incarnation: 0 };
   const t2 = { vatID, startPos: 2, endPos: 4, isCurrent: 0, incarnation: 0 };
   const t4 = { vatID, startPos: 4, endPos: 6, isCurrent: 0, incarnation: 1 };
-  const tc = { vatID, startPos: 6, endPos: 8, isCurrent: 1, incarnation: 1 };
   const t6 = { vatID, startPos: 6, endPos: 8, isCurrent: 0, incarnation: 1 };
-  compareNoHash(t, currentExportData, {
+  const expectedLiveExportData = {
     'transcript.v1.0': t0,
     'transcript.v1.2': t2,
     'transcript.v1.4': t4,
-    'transcript.v1.current': tc,
-  });
-
+    'transcript.v1.current': { ...t6, isCurrent: 1 },
+  };
+  const expectedStoppedExportData = {
+    'transcript.v1.0': t0,
+    'transcript.v1.2': t2,
+    'transcript.v1.4': t4,
+    'transcript.v1.6': t6,
+  };
+  const expectedArtifactNames = [
+    'transcript.v1.0.2',
+    'transcript.v1.2.4',
+    'transcript.v1.4.6',
+    'transcript.v1.6.8',
+  ];
+
+  compareNoHash(t, currentExportData, expectedLiveExportData);
   t.is(db.prepare('SELECT COUNT(*) FROM transcriptItems').pluck().get(), 8);
   t.is(db.prepare('SELECT COUNT(*) FROM transcriptSpans').pluck().get(), 4);
 
@@ -237,13 +249,8 @@ test('slow deletion of transcripts', async t => {
   {
     const { exportData, artifactNames } = await getExport(dbDir, 'operational');
     t.deepEqual(currentExportData, mapToObj(exportData));
-    compareNoHash(t, mapToObj(exportData), {
-      'transcript.v1.0': t0,
-      'transcript.v1.2': t2,
-      'transcript.v1.4': t4,
-      'transcript.v1.current': tc,
-    });
-    t.deepEqual(artifactNames, ['transcript.v1.6.8']);
+    compareNoHash(t, mapToObj(exportData), expectedLiveExportData);
+    t.deepEqual(artifactNames, expectedArtifactNames.slice(-1));
     const db2 = await reImport(t, dbDir, 'operational');
     t.is(db2.prepare('SELECT COUNT(*) FROM transcriptItems').pluck().get(), 2);
     t.is(db2.prepare('SELECT COUNT(*) FROM transcriptSpans').pluck().get(), 4);
@@ -253,18 +260,8 @@ test('slow deletion of transcripts', async t => {
   // artifacts for each
   {
     const { exportData, artifactNames } = await getExport(dbDir, 'archival');
-    compareNoHash(t, mapToObj(exportData), {
-      'transcript.v1.0': t0,
-      'transcript.v1.2': t2,
-      'transcript.v1.4': t4,
-      'transcript.v1.current': tc,
-    });
-    t.deepEqual(artifactNames, [
-      'transcript.v1.0.2',
-      'transcript.v1.2.4',
-      'transcript.v1.4.6',
-      'transcript.v1.6.8',
-    ]);
+    compareNoHash(t, mapToObj(exportData), expectedLiveExportData);
+    t.deepEqual(artifactNames, expectedArtifactNames);
     const db2 = await reImport(t, dbDir, 'archival');
     t.is(db2.prepare('SELECT COUNT(*) FROM transcriptItems').pluck().get(), 8);
     t.is(db2.prepare('SELECT COUNT(*) FROM transcriptSpans').pluck().get(), 4);
@@ -276,12 +273,7 @@ test('slow deletion of transcripts', async t => {
   {
     transcriptStore.stopUsingTranscript(vatID);
     await commit();
-    compareNoHash(t, currentExportData, {
-      'transcript.v1.0': t0,
-      'transcript.v1.2': t2,
-      'transcript.v1.4': t4,
-      'transcript.v1.6': t6,
-    });
+    compareNoHash(t, currentExportData, expectedStoppedExportData);
     exportLog.length = 0;
     // stopUsingTranscript is idempotent
     transcriptStore.stopUsingTranscript(vatID);
@@ -294,39 +286,33 @@ test('slow deletion of transcripts', async t => {
   // debug-mode will have artifacts.
   for (const mode of ['operational', 'replay', 'archival', 'debug']) {
     const { exportData, artifactNames } = await getExport(dbDir, mode);
-    compareNoHash(t, mapToObj(exportData), {
-      'transcript.v1.0': t0,
-      'transcript.v1.2': t2,
-      'transcript.v1.4': t4,
-      'transcript.v1.6': t6,
-    });
-    if (mode === 'debug') {
-      t.deepEqual(artifactNames, [
-        'transcript.v1.0.2',
-        'transcript.v1.2.4',
-        'transcript.v1.4.6',
-        'transcript.v1.6.8',
-      ]);
-    } else {
-      t.deepEqual(artifactNames, []);
-    }
+    compareNoHash(
+      t,
+      mapToObj(exportData),
+      expectedStoppedExportData,
+      `${mode} stopped-vat export data`,
+    );
+    t.deepEqual(
+      artifactNames,
+      mode === 'debug' ? expectedArtifactNames : [],
+      `${mode} stopped-vat export artifacts`,
+    );
     const db2 = await reImport(t, dbDir, 'operational');
     t.is(db2.prepare('SELECT COUNT(*) FROM transcriptItems').pluck().get(), 0);
     t.is(db2.prepare('SELECT COUNT(*) FROM transcriptSpans').pluck().get(), 4);
   }
 
   // first deletion
+  const expectedTruncatedExportData1 = Object.fromEntries(
+    Object.entries(expectedStoppedExportData).slice(0, -1),
+  );
   {
     // budget=1 will let it delete one span, the last one
     const dc = transcriptStore.deleteVatTranscripts(vatID, 1);
     t.false(dc.done);
     t.is(dc.cleanups, 1);
     await commit();
-    compareNoHash(t, currentExportData, {
-      'transcript.v1.0': t0,
-      'transcript.v1.2': t2,
-      'transcript.v1.4': t4,
-    });
+    compareNoHash(t, currentExportData, expectedTruncatedExportData1);
     t.is(db.prepare('SELECT COUNT(*) FROM transcriptItems').pluck().get(), 6);
     t.is(db.prepare('SELECT COUNT(*) FROM transcriptSpans').pluck().get(), 3);
   }
@@ -339,50 +325,48 @@ test('slow deletion of transcripts', async t => {
 
   for (const mode of ['operational', 'replay', 'archival', 'debug']) {
     const { exportData, artifactNames } = await getExport(dbDir, mode);
-    compareNoHash(t, mapToObj(exportData), {
-      'transcript.v1.0': t0,
-      'transcript.v1.2': t2,
-      'transcript.v1.4': t4,
-    });
-    if (mode === 'debug') {
-      t.deepEqual(artifactNames, [
-        'transcript.v1.0.2',
-        'transcript.v1.2.4',
-        'transcript.v1.4.6',
-      ]);
-    } else {
-      t.deepEqual(artifactNames, []);
-    }
+    compareNoHash(
+      t,
+      mapToObj(exportData),
+      expectedTruncatedExportData1,
+      `${mode} first-deletion export data`,
+    );
+    t.deepEqual(
+      artifactNames,
+      mode === 'debug' ? expectedArtifactNames.slice(0, -1) : [],
+      `${mode} first-deletion export artifacts`,
+    );
     const db2 = await reImport(t, dbDir, 'operational');
     t.is(db2.prepare('SELECT COUNT(*) FROM transcriptItems').pluck().get(), 0);
     t.is(db2.prepare('SELECT COUNT(*) FROM transcriptSpans').pluck().get(), 3);
   }
 
   // second deletion
+  const expectedTruncatedExportData2 = Object.fromEntries(
+    Object.entries(expectedStoppedExportData).slice(0, -2),
+  );
   {
     const dc = transcriptStore.deleteVatTranscripts(vatID, 1);
     t.false(dc.done);
     t.is(dc.cleanups, 1);
     await commit();
-    compareNoHash(t, currentExportData, {
-      'transcript.v1.0': t0,
-      'transcript.v1.2': t2,
-    });
+    compareNoHash(t, currentExportData, expectedTruncatedExportData2);
     t.is(db.prepare('SELECT COUNT(*) FROM transcriptItems').pluck().get(), 4);
     t.is(db.prepare('SELECT COUNT(*) FROM transcriptSpans').pluck().get(), 2);
   }
-
   for (const mode of ['operational', 'replay', 'archival', 'debug']) {
     const { exportData, artifactNames } = await getExport(dbDir, mode);
-    compareNoHash(t, mapToObj(exportData), {
-      'transcript.v1.0': t0,
-      'transcript.v1.2': t2,
-    });
-    if (mode === 'debug') {
-      t.deepEqual(artifactNames, ['transcript.v1.0.2', 'transcript.v1.2.4']);
-    } else {
-      t.deepEqual(artifactNames, []);
-    }
+    compareNoHash(
+      t,
+      mapToObj(exportData),
+      expectedTruncatedExportData2,
+      `${mode} second-deletion export data`,
+    );
+    t.deepEqual(
+      artifactNames,
+      mode === 'debug' ? expectedArtifactNames.slice(0, -2) : [],
+      `${mode} second-deletion export artifacts`,
+    );
     const db2 = await reImport(t, dbDir, 'operational');
     t.is(db2.prepare('SELECT COUNT(*) FROM transcriptItems').pluck().get(), 0);
     t.is(db2.prepare('SELECT COUNT(*) FROM transcriptSpans').pluck().get(), 2);
@@ -398,11 +382,15 @@ test('slow deletion of transcripts', async t => {
     t.is(db.prepare('SELECT COUNT(*) FROM transcriptItems').pluck().get(), 0);
     t.is(db.prepare('SELECT COUNT(*) FROM transcriptSpans').pluck().get(), 0);
   }
-
   for (const mode of ['operational', 'replay', 'archival', 'debug']) {
     const { exportData, artifactNames } = await getExport(dbDir, mode);
-    compareNoHash(t, mapToObj(exportData), {});
-    t.deepEqual(artifactNames, []);
+    compareNoHash(
+      t,
+      mapToObj(exportData),
+      {},
+      `${mode} final-deletion export data`,
+    );
+    t.deepEqual(artifactNames, [], `${mode} final-deletion export artifacts`);
     const db2 = await reImport(t, dbDir, 'operational');
     t.is(db2.prepare('SELECT COUNT(*) FROM transcriptItems').pluck().get(), 0);
     t.is(db2.prepare('SELECT COUNT(*) FROM transcriptSpans').pluck().get(), 0);

From 235c4580f43dc0acc5ff8c280c92bacf6434c3a8 Mon Sep 17 00:00:00 2001
From: Richard Gibson <richard.gibson@gmail.com>
Date: Fri, 6 Sep 2024 16:23:38 -0400
Subject: [PATCH 4/8] test(swing-store): Refactor helpers for consistency and
 brevity

---
 packages/swing-store/test/deletion.test.js | 46 +++++++++++-----------
 1 file changed, 23 insertions(+), 23 deletions(-)

diff --git a/packages/swing-store/test/deletion.test.js b/packages/swing-store/test/deletion.test.js
index 37917cde345..27629fbfd25 100644
--- a/packages/swing-store/test/deletion.test.js
+++ b/packages/swing-store/test/deletion.test.js
@@ -143,13 +143,17 @@ const reImport = async (t, dbDir, artifactMode) => {
   return sqlite3(path.join(dbDir2, 'swingstore.sqlite'));
 };
 
-const compareNoHash = (t, actual, expected, message) => {
+const stripHashes = exportData => {
   const stripped = {};
-  for (const [key, value] of Object.entries(actual)) {
+  const entries =
+    exportData instanceof Map
+      ? exportData.entries()
+      : Object.entries(exportData);
+  for (const [key, value] of entries) {
     const { hash: _, ...data } = JSON.parse(value);
     stripped[key] = data;
   }
-  return t.deepEqual(stripped, expected, message);
+  return stripped;
 };
 
 const setupTranscript = async t => {
@@ -240,7 +244,7 @@ test('slow deletion of transcripts', async t => {
     'transcript.v1.6.8',
   ];
 
-  compareNoHash(t, currentExportData, expectedLiveExportData);
+  t.deepEqual(stripHashes(currentExportData), expectedLiveExportData);
   t.is(db.prepare('SELECT COUNT(*) FROM transcriptItems').pluck().get(), 8);
   t.is(db.prepare('SELECT COUNT(*) FROM transcriptSpans').pluck().get(), 4);
 
@@ -249,7 +253,7 @@ test('slow deletion of transcripts', async t => {
   {
     const { exportData, artifactNames } = await getExport(dbDir, 'operational');
     t.deepEqual(currentExportData, mapToObj(exportData));
-    compareNoHash(t, mapToObj(exportData), expectedLiveExportData);
+    t.deepEqual(stripHashes(exportData), expectedLiveExportData);
     t.deepEqual(artifactNames, expectedArtifactNames.slice(-1));
     const db2 = await reImport(t, dbDir, 'operational');
     t.is(db2.prepare('SELECT COUNT(*) FROM transcriptItems').pluck().get(), 2);
@@ -260,7 +264,7 @@ test('slow deletion of transcripts', async t => {
   // artifacts for each
   {
     const { exportData, artifactNames } = await getExport(dbDir, 'archival');
-    compareNoHash(t, mapToObj(exportData), expectedLiveExportData);
+    t.deepEqual(stripHashes(exportData), expectedLiveExportData);
     t.deepEqual(artifactNames, expectedArtifactNames);
     const db2 = await reImport(t, dbDir, 'archival');
     t.is(db2.prepare('SELECT COUNT(*) FROM transcriptItems').pluck().get(), 8);
@@ -273,7 +277,7 @@ test('slow deletion of transcripts', async t => {
   {
     transcriptStore.stopUsingTranscript(vatID);
     await commit();
-    compareNoHash(t, currentExportData, expectedStoppedExportData);
+    t.deepEqual(stripHashes(currentExportData), expectedStoppedExportData);
     exportLog.length = 0;
     // stopUsingTranscript is idempotent
     transcriptStore.stopUsingTranscript(vatID);
@@ -286,9 +290,8 @@ test('slow deletion of transcripts', async t => {
   // debug-mode will have artifacts.
   for (const mode of ['operational', 'replay', 'archival', 'debug']) {
     const { exportData, artifactNames } = await getExport(dbDir, mode);
-    compareNoHash(
-      t,
-      mapToObj(exportData),
+    t.deepEqual(
+      stripHashes(exportData),
       expectedStoppedExportData,
       `${mode} stopped-vat export data`,
     );
@@ -312,7 +315,7 @@ test('slow deletion of transcripts', async t => {
     t.false(dc.done);
     t.is(dc.cleanups, 1);
     await commit();
-    compareNoHash(t, currentExportData, expectedTruncatedExportData1);
+    t.deepEqual(stripHashes(currentExportData), expectedTruncatedExportData1);
     t.is(db.prepare('SELECT COUNT(*) FROM transcriptItems').pluck().get(), 6);
     t.is(db.prepare('SELECT COUNT(*) FROM transcriptSpans').pluck().get(), 3);
   }
@@ -325,9 +328,8 @@ test('slow deletion of transcripts', async t => {
 
   for (const mode of ['operational', 'replay', 'archival', 'debug']) {
     const { exportData, artifactNames } = await getExport(dbDir, mode);
-    compareNoHash(
-      t,
-      mapToObj(exportData),
+    t.deepEqual(
+      stripHashes(exportData),
       expectedTruncatedExportData1,
       `${mode} first-deletion export data`,
     );
@@ -350,15 +352,14 @@ test('slow deletion of transcripts', async t => {
     t.false(dc.done);
     t.is(dc.cleanups, 1);
     await commit();
-    compareNoHash(t, currentExportData, expectedTruncatedExportData2);
+    t.deepEqual(stripHashes(currentExportData), expectedTruncatedExportData2);
     t.is(db.prepare('SELECT COUNT(*) FROM transcriptItems').pluck().get(), 4);
     t.is(db.prepare('SELECT COUNT(*) FROM transcriptSpans').pluck().get(), 2);
   }
   for (const mode of ['operational', 'replay', 'archival', 'debug']) {
     const { exportData, artifactNames } = await getExport(dbDir, mode);
-    compareNoHash(
-      t,
-      mapToObj(exportData),
+    t.deepEqual(
+      stripHashes(exportData),
       expectedTruncatedExportData2,
       `${mode} second-deletion export data`,
     );
@@ -378,15 +379,14 @@ test('slow deletion of transcripts', async t => {
     t.true(dc.done);
     t.is(dc.cleanups, 2);
     await commit();
-    compareNoHash(t, currentExportData, {});
+    t.deepEqual(stripHashes(currentExportData), {});
     t.is(db.prepare('SELECT COUNT(*) FROM transcriptItems').pluck().get(), 0);
     t.is(db.prepare('SELECT COUNT(*) FROM transcriptSpans').pluck().get(), 0);
   }
   for (const mode of ['operational', 'replay', 'archival', 'debug']) {
     const { exportData, artifactNames } = await getExport(dbDir, mode);
-    compareNoHash(
-      t,
-      mapToObj(exportData),
+    t.deepEqual(
+      stripHashes(exportData),
       {},
       `${mode} final-deletion export data`,
     );
@@ -424,7 +424,7 @@ test('slow deletion without stopUsingTranscript', async t => {
     const t0 = { vatID, startPos: 0, endPos: 2, isCurrent: 0, incarnation: 0 };
     const t2 = { vatID, startPos: 2, endPos: 4, isCurrent: 0, incarnation: 0 };
     const t4 = { vatID, startPos: 4, endPos: 6, isCurrent: 0, incarnation: 1 };
-    compareNoHash(t, currentExportData, {
+    t.deepEqual(stripHashes(currentExportData), {
       'transcript.v1.0': t0,
       'transcript.v1.2': t2,
       'transcript.v1.4': t4,

From 396d6f82a6e40ae6ec343505ccf0ffa290cc1f77 Mon Sep 17 00:00:00 2001
From: Richard Gibson <richard.gibson@gmail.com>
Date: Fri, 6 Sep 2024 16:23:38 -0400
Subject: [PATCH 5/8] test(swing-store): Cover stopUsingTranscript with
 keepTranscripts=false

(currently failing because stopUsingTranscript does not delete the
previously-current span)
---
 packages/swing-store/test/deletion.test.js | 56 ++++++++++++++++------
 1 file changed, 42 insertions(+), 14 deletions(-)

diff --git a/packages/swing-store/test/deletion.test.js b/packages/swing-store/test/deletion.test.js
index 27629fbfd25..114c33514a4 100644
--- a/packages/swing-store/test/deletion.test.js
+++ b/packages/swing-store/test/deletion.test.js
@@ -156,7 +156,7 @@ const stripHashes = exportData => {
   return stripped;
 };
 
-const setupTranscript = async t => {
+const setupTranscript = async (t, keepTranscripts) => {
   const vatID = 'v1';
   const exportLog = [];
   const currentExportData = {};
@@ -168,7 +168,7 @@ const setupTranscript = async t => {
   };
   const [dbDir, cleanup] = await tmpDir('testdb');
   t.teardown(cleanup);
-  const store = initSwingStore(dbDir, { exportCallback });
+  const store = initSwingStore(dbDir, { exportCallback, keepTranscripts });
   const { kernelStorage, hostStorage } = store;
   const { transcriptStore } = kernelStorage;
   const { commit } = hostStorage;
@@ -201,7 +201,11 @@ const setupTranscript = async t => {
   };
 };
 
-test('slow deletion of transcripts', async t => {
+/**
+ * @param {import('ava').ExecutionContext} t
+ * @param {{ keepTranscripts: boolean }} config
+ */
+const execSlowTranscriptDeletion = async (t, { keepTranscripts }) => {
   // slow transcript deletion should remove export-data as it removes
   // transcript spans and their items
 
@@ -213,7 +217,7 @@ test('slow deletion of transcripts', async t => {
     exportLog,
     currentExportData,
     vatID,
-  } = await setupTranscript(t);
+  } = await setupTranscript(t, keepTranscripts);
 
   arrayIsLike(t, exportLog.splice(0), [
     ['transcript.v1.0'],
@@ -245,7 +249,10 @@ test('slow deletion of transcripts', async t => {
   ];
 
   t.deepEqual(stripHashes(currentExportData), expectedLiveExportData);
-  t.is(db.prepare('SELECT COUNT(*) FROM transcriptItems').pluck().get(), 8);
+  t.is(
+    db.prepare('SELECT COUNT(*) FROM transcriptItems').pluck().get(),
+    keepTranscripts ? 8 : 2,
+  );
   t.is(db.prepare('SELECT COUNT(*) FROM transcriptSpans').pluck().get(), 4);
 
   // an "operational"-mode export should list all spans, but only have
@@ -260,9 +267,11 @@ test('slow deletion of transcripts', async t => {
     t.is(db2.prepare('SELECT COUNT(*) FROM transcriptSpans').pluck().get(), 4);
   }
 
-  // an "archival"-mode export should list all four spans, with
-  // artifacts for each
-  {
+  // an "archival"-mode export should list all four spans with
+  // artifacts for each, but is only available with keepTranscripts=true
+  if (!keepTranscripts) {
+    await t.throwsAsync(getExport(dbDir, 'archival'));
+  } else {
     const { exportData, artifactNames } = await getExport(dbDir, 'archival');
     t.deepEqual(stripHashes(exportData), expectedLiveExportData);
     t.deepEqual(artifactNames, expectedArtifactNames);
@@ -287,7 +296,7 @@ test('slow deletion of transcripts', async t => {
 
   // All exports (debug and non-debug) in this "terminated but not
   // deleted" state will still have the export-data keys. Only
-  // debug-mode will have artifacts.
+  // debug-mode will have artifacts (and only with keepTranscripts=true).
   for (const mode of ['operational', 'replay', 'archival', 'debug']) {
     const { exportData, artifactNames } = await getExport(dbDir, mode);
     t.deepEqual(
@@ -297,7 +306,7 @@ test('slow deletion of transcripts', async t => {
     );
     t.deepEqual(
       artifactNames,
-      mode === 'debug' ? expectedArtifactNames : [],
+      mode === 'debug' && keepTranscripts ? expectedArtifactNames : [],
       `${mode} stopped-vat export artifacts`,
     );
     const db2 = await reImport(t, dbDir, 'operational');
@@ -316,7 +325,10 @@ test('slow deletion of transcripts', async t => {
     t.is(dc.cleanups, 1);
     await commit();
     t.deepEqual(stripHashes(currentExportData), expectedTruncatedExportData1);
-    t.is(db.prepare('SELECT COUNT(*) FROM transcriptItems').pluck().get(), 6);
+    t.is(
+      db.prepare('SELECT COUNT(*) FROM transcriptItems').pluck().get(),
+      keepTranscripts ? 6 : 0,
+    );
     t.is(db.prepare('SELECT COUNT(*) FROM transcriptSpans').pluck().get(), 3);
   }
 
@@ -335,7 +347,9 @@ test('slow deletion of transcripts', async t => {
     );
     t.deepEqual(
       artifactNames,
-      mode === 'debug' ? expectedArtifactNames.slice(0, -1) : [],
+      mode === 'debug' && keepTranscripts
+        ? expectedArtifactNames.slice(0, -1)
+        : [],
       `${mode} first-deletion export artifacts`,
     );
     const db2 = await reImport(t, dbDir, 'operational');
@@ -353,7 +367,10 @@ test('slow deletion of transcripts', async t => {
     t.is(dc.cleanups, 1);
     await commit();
     t.deepEqual(stripHashes(currentExportData), expectedTruncatedExportData2);
-    t.is(db.prepare('SELECT COUNT(*) FROM transcriptItems').pluck().get(), 4);
+    t.is(
+      db.prepare('SELECT COUNT(*) FROM transcriptItems').pluck().get(),
+      keepTranscripts ? 4 : 0,
+    );
     t.is(db.prepare('SELECT COUNT(*) FROM transcriptSpans').pluck().get(), 2);
   }
   for (const mode of ['operational', 'replay', 'archival', 'debug']) {
@@ -365,7 +382,9 @@ test('slow deletion of transcripts', async t => {
     );
     t.deepEqual(
       artifactNames,
-      mode === 'debug' ? expectedArtifactNames.slice(0, -2) : [],
+      mode === 'debug' && keepTranscripts
+        ? expectedArtifactNames.slice(0, -2)
+        : [],
       `${mode} second-deletion export artifacts`,
     );
     const db2 = await reImport(t, dbDir, 'operational');
@@ -405,7 +424,16 @@ test('slow deletion of transcripts', async t => {
     await commit();
     t.deepEqual(exportLog, []);
   }
+};
+const testSlowTranscriptDeletion = test.macro({
+  title(extra = '', { keepTranscripts }) {
+    const detail = keepTranscripts ? 'with retention' : 'without retention';
+    return `slow deletion of transcripts ${detail}${extra.replace(/.$/, ' $&')}`;
+  },
+  exec: execSlowTranscriptDeletion,
 });
+test(testSlowTranscriptDeletion, { keepTranscripts: true });
+test.failing(testSlowTranscriptDeletion, { keepTranscripts: false });
 
 test('slow deletion without stopUsingTranscript', async t => {
   // slow deletion should work even without stopUsingTranscript

From 677849d85ece43bbf5c610d4b78bc7748d986ec7 Mon Sep 17 00:00:00 2001
From: Richard Gibson <richard.gibson@gmail.com>
Date: Fri, 6 Sep 2024 16:19:51 -0400
Subject: [PATCH 6/8] refactor(swing-store): Consolidate common behavior for
 span rollover and stopUsingTranscript

---
 packages/swing-store/src/transcriptStore.js | 48 +++++++++++++--------
 1 file changed, 30 insertions(+), 18 deletions(-)

diff --git a/packages/swing-store/src/transcriptStore.js b/packages/swing-store/src/transcriptStore.js
index d5d9a1bb1e2..bde8b7d6eae 100644
--- a/packages/swing-store/src/transcriptStore.js
+++ b/packages/swing-store/src/transcriptStore.js
@@ -257,18 +257,37 @@ export function makeTranscriptStore(
     WHERE vatID = ? AND position >= ? AND position < ?
   `);
 
-  function doSpanRollover(vatID, isNewIncarnation) {
+  /**
+   * Finalize a span, setting isCurrent to null, marking the resulting record
+   * for export, and effecting disk archival and database cleanup as
+   * configured.
+   * Note that creation of a new DB row and removal/replacement of the
+   * transcript.${vatID}.current export record are responsibility of the caller.
+   *
+   * @param {string} vatID
+   * @param {ReturnType<getCurrentSpanBounds>} bounds
+   */
+  function closeSpan(vatID, bounds) {
     ensureTxn();
-    const { startPos, endPos, hash, incarnation } = getCurrentSpanBounds(vatID);
-    const oldRec = spanRec(vatID, startPos, endPos, hash, false, incarnation);
+    const { startPos, endPos, hash, incarnation } = bounds;
+    const rec = spanRec(vatID, startPos, endPos, hash, false, incarnation);
 
-    // add a new record for the now-old span
-    noteExport(spanMetadataKey(oldRec), JSON.stringify(oldRec));
+    // add a new export record for the now-old span
+    noteExport(spanMetadataKey(rec), JSON.stringify(rec));
 
     // and change its DB row to isCurrent=null
     sqlEndCurrentSpan.run(vatID);
+  }
+
+  function doSpanRollover(vatID, isNewIncarnation) {
+    ensureTxn();
+    const bounds = getCurrentSpanBounds(vatID);
+    const { startPos, endPos, incarnation } = bounds;
+
+    // deal with the now-old span
+    closeSpan(vatID, bounds);
 
-    // create a new (empty) row, with isCurrent=1
+    // create a new (empty) DB row, with isCurrent=1
     const incarnationToUse = isNewIncarnation ? incarnation + 1 : incarnation;
     sqlWriteSpan.run(vatID, endPos, endPos, initialHash, 1, incarnationToUse);
 
@@ -369,21 +388,14 @@ export function makeTranscriptStore(
    */
   function stopUsingTranscript(vatID) {
     ensureTxn();
-    // this transforms the current span into a (short) historical one
-    // (basically doSpanRollover without adding replacement data)
     const bounds = sqlGetCurrentSpanBounds.get(vatID);
-    if (bounds) {
-      // add a new record for the now-old span
-      const { startPos, endPos, hash, incarnation } = bounds;
-      const oldRec = spanRec(vatID, startPos, endPos, hash, false, incarnation);
-      noteExport(spanMetadataKey(oldRec), JSON.stringify(oldRec));
+    if (!bounds) return;
 
-      // and change its DB row to isCurrent=null
-      sqlEndCurrentSpan.run(vatID);
+    // deal with the now-old span
+    closeSpan(vatID, bounds);
 
-      // remove the transcript.${vatID}.current record
-      noteExport(spanMetadataKey({ vatID, isCurrent: true }), undefined);
-    }
+    // remove the transcript.${vatID}.current record
+    noteExport(spanMetadataKey({ vatID, isCurrent: true }), undefined);
   }
 
   /**

From 5eb08e22841b2d40085d7c5f1e768073de2903fb Mon Sep 17 00:00:00 2001
From: Richard Gibson <richard.gibson@gmail.com>
Date: Fri, 6 Sep 2024 17:42:54 -0400
Subject: [PATCH 7/8] style(swing-store): Use a more readable variable name

---
 packages/swing-store/src/transcriptStore.js | 8 ++++----
 1 file changed, 4 insertions(+), 4 deletions(-)

diff --git a/packages/swing-store/src/transcriptStore.js b/packages/swing-store/src/transcriptStore.js
index bde8b7d6eae..a40500f0475 100644
--- a/packages/swing-store/src/transcriptStore.js
+++ b/packages/swing-store/src/transcriptStore.js
@@ -288,8 +288,8 @@ export function makeTranscriptStore(
     closeSpan(vatID, bounds);
 
     // create a new (empty) DB row, with isCurrent=1
-    const incarnationToUse = isNewIncarnation ? incarnation + 1 : incarnation;
-    sqlWriteSpan.run(vatID, endPos, endPos, initialHash, 1, incarnationToUse);
+    const newSpanIncarnation = isNewIncarnation ? incarnation + 1 : incarnation;
+    sqlWriteSpan.run(vatID, endPos, endPos, initialHash, 1, newSpanIncarnation);
 
     // overwrite the transcript.${vatID}.current record with new span
     const rec = spanRec(
@@ -298,7 +298,7 @@ export function makeTranscriptStore(
       endPos,
       initialHash,
       true,
-      incarnationToUse,
+      newSpanIncarnation,
     );
     noteExport(spanMetadataKey(rec), JSON.stringify(rec));
 
@@ -311,7 +311,7 @@ export function makeTranscriptStore(
       // that doesn't include them.
       sqlDeleteOldItems.run(vatID, startPos, endPos);
     }
-    return incarnationToUse;
+    return newSpanIncarnation;
   }
 
   /**

From 2d1e47844760e0534afb3fe410a9635656949dad Mon Sep 17 00:00:00 2001
From: Richard Gibson <richard.gibson@gmail.com>
Date: Fri, 6 Sep 2024 17:44:43 -0400
Subject: [PATCH 8/8] fix(swing-store): Delete transcript spans in
 stopUsingTranscript as in rollover

Fixes #10054
---
 packages/swing-store/src/transcriptStore.js | 21 +++++++++++----------
 packages/swing-store/test/deletion.test.js  |  2 +-
 2 files changed, 12 insertions(+), 11 deletions(-)

diff --git a/packages/swing-store/src/transcriptStore.js b/packages/swing-store/src/transcriptStore.js
index a40500f0475..649df9f5f97 100644
--- a/packages/swing-store/src/transcriptStore.js
+++ b/packages/swing-store/src/transcriptStore.js
@@ -277,12 +277,22 @@ export function makeTranscriptStore(
 
     // and change its DB row to isCurrent=null
     sqlEndCurrentSpan.run(vatID);
+
+    if (!keepTranscripts) {
+      // Delete items of the previously-current span.
+      // There may still be items associated with even older spans, but we leave
+      // those, to avoid excessive DB churn (for details, see #9387 and #9174).
+      // Recovery of space claimed by such ancient items is expected to use an
+      // external mechanism such as restoration from an operational snapshot
+      // that doesn't include them.
+      sqlDeleteOldItems.run(vatID, startPos, endPos);
+    }
   }
 
   function doSpanRollover(vatID, isNewIncarnation) {
     ensureTxn();
     const bounds = getCurrentSpanBounds(vatID);
-    const { startPos, endPos, incarnation } = bounds;
+    const { endPos, incarnation } = bounds;
 
     // deal with the now-old span
     closeSpan(vatID, bounds);
@@ -302,15 +312,6 @@ export function makeTranscriptStore(
     );
     noteExport(spanMetadataKey(rec), JSON.stringify(rec));
 
-    if (!keepTranscripts) {
-      // Delete items of the previously-current span.
-      // There may still be items associated with even older spans, but we leave
-      // those, to avoid excessive DB churn (for details, see #9387 and #9174).
-      // Recovery of space claimed by such ancient items is expected to use an
-      // external mechanism such as restoration from an operational snapshot
-      // that doesn't include them.
-      sqlDeleteOldItems.run(vatID, startPos, endPos);
-    }
     return newSpanIncarnation;
   }
 
diff --git a/packages/swing-store/test/deletion.test.js b/packages/swing-store/test/deletion.test.js
index 114c33514a4..5d39cf58840 100644
--- a/packages/swing-store/test/deletion.test.js
+++ b/packages/swing-store/test/deletion.test.js
@@ -433,7 +433,7 @@ const testSlowTranscriptDeletion = test.macro({
   exec: execSlowTranscriptDeletion,
 });
 test(testSlowTranscriptDeletion, { keepTranscripts: true });
-test.failing(testSlowTranscriptDeletion, { keepTranscripts: false });
+test(testSlowTranscriptDeletion, { keepTranscripts: false });
 
 test('slow deletion without stopUsingTranscript', async t => {
   // slow deletion should work even without stopUsingTranscript