feat(session): default JSONL writes to packed rows

packages/session-persistence/session-persistence-jsonl/tests/jsonl.spec.ts

@@ -724,7 +724,7 @@ describe('SessionPersistenceJsonl: scanLog unit', () => {
   })
 })
 
-describe('SessionPersistenceJsonl: packed chunk rows (packChunks: true)', () => {
+describe('SessionPersistenceJsonl: default packed chunk rows', () => {
   let ctx: Context
   beforeEach(async () => {
     root = await freshRoot()
@@ -732,7 +732,7 @@ describe('SessionPersistenceJsonl: packed chunk rows (packChunks: true)', () =>
     await ctx.plugin(SessionStore)
     // compression: 'none' — these tests assert the textual storage-record layout
     // (row tags per line); packing is orthogonal to the physical encoding.
-    await ctx.plugin(SessionPersistenceJsonl, { root, packChunks: true, compression: 'none' })
+    await ctx.plugin(SessionPersistenceJsonl, { root, compression: 'none' })
   })
   afterEach(async () => { await ctx.fiber.dispose() })
 
@@ -754,7 +754,7 @@ describe('SessionPersistenceJsonl: packed chunk rows (packChunks: true)', () =>
     ]
   }
 
-  it('writes a delta run as one text-chunks row and loads back identical events', async () => {
+  it('writes a delta run as one text-chunks row by default and loads back identical events', async () => {
     const m = meta('packed', '/work')
     const log = chunkRunLog()
     await ctx.sessionPersistence.create(m)
@@ -768,6 +768,32 @@ describe('SessionPersistenceJsonl: packed chunk rows (packChunks: true)', () =>
     expect(loaded.events).toEqual(log)
   })
 
+  it('packChunks: false writes one event per line and still loads identical events', async () => {
+    const unpackedRoot = await freshRoot()
+    const unpacked = new Context()
+    await unpacked.plugin(SessionStore)
+    await unpacked.plugin(SessionPersistenceJsonl, {
+      root: unpackedRoot,
+      packChunks: false,
+      compression: 'none',
+    })
+    try {
+      const m = meta('unpacked', '/work')
+      const log = chunkRunLog()
+      await unpacked.sessionPersistence.create(m)
+      await unpacked.sessionPersistence.append(m.id, log)
+
+      const records = (await readFile(rawLogPath(unpackedRoot, '/work', m.id), 'utf8'))
+        .split('\n').filter(Boolean).slice(1)
+        .map(line => JSON.parse(line) as { type: string })
+      expect(records.filter(record => record.type === 'assistant/chunk')).toHaveLength(5)
+      expect(records.some(record => record.type === 'text-chunks')).toBe(false)
+      expect((await unpacked.sessionPersistence.load(m.id)).events).toEqual(log)
+    } finally {
+      await unpacked.fiber.dispose()
+    }
+  })
+
   it('loads a mixed file: verbatim lines from an unpacked writer, then packed appends', async () => {
     const m = meta('mixed', '/work')
     const log = chunkRunLog()