fix(session): detect post-compaction no-text degradation and trigger recovery (fixes #2232)

2026-03-18 16:13:23 +09:00
parent 01e18f8773
commit b8f3186d65
4 changed files with 432 additions and 21 deletions
@@ -0,0 +1,138 @@
+import { beforeEach, describe, expect, it, mock } from "bun:test"
+
+const logMock = mock(() => {})
+
+mock.module("../shared/logger", () => ({
+  log: logMock,
+}))
+
+const { createPreemptiveCompactionHook } = await import("./preemptive-compaction")
+
+function createMockCtx() {
+  return {
+    client: {
+      session: {
+        messages: mock(() => Promise.resolve({ data: [] })),
+        summarize: mock(() => Promise.resolve({})),
+      },
+      tui: {
+        showToast: mock(() => Promise.resolve({})),
+      },
+    },
+    directory: "/tmp/test",
+  }
+}
+
+function buildAssistantUpdate(input: {
+  sessionID: string
+  id: string
+  parts: unknown[]
+}): {
+  event: {
+    type: string
+    properties: {
+      info: {
+        id: string
+        role: string
+        sessionID: string
+        providerID: string
+        modelID: string
+        finish: boolean
+        tokens: { input: number; output: number; reasoning: number; cache: { read: number; write: number } }
+        parts: unknown[]
+      }
+    }
+  }
+} {
+  return {
+    event: {
+      type: "message.updated",
+      properties: {
+        info: {
+          id: input.id,
+          role: "assistant",
+          sessionID: input.sessionID,
+          providerID: "anthropic",
+          modelID: "claude-sonnet-4-6",
+          finish: true,
+          tokens: { input: 1000, output: 10, reasoning: 0, cache: { read: 0, write: 0 } },
+          parts: input.parts,
+        },
+      },
+    },
+  }
+}
+
+describe("preemptive-compaction post-compaction degradation monitor", () => {
+  beforeEach(() => {
+    logMock.mockClear()
+  })
+
+  it("triggers recovery summarize after three consecutive no-text tail messages", async () => {
+    const ctx = createMockCtx()
+    const hook = createPreemptiveCompactionHook(ctx as never, {} as never)
+    const sessionID = "ses_tail_recovery"
+
+    await hook.event({
+      event: {
+        type: "session.compacted",
+        properties: { sessionID },
+      },
+    })
+
+    const stepOnlyParts = [{ type: "step-start" }, { type: "step-finish" }]
+
+    await hook.event(buildAssistantUpdate({ sessionID, id: "msg_1", parts: stepOnlyParts }))
+    await hook.event(buildAssistantUpdate({ sessionID, id: "msg_2", parts: stepOnlyParts }))
+    await hook.event(buildAssistantUpdate({ sessionID, id: "msg_3", parts: stepOnlyParts }))
+
+    expect(ctx.client.session.summarize).toHaveBeenCalledTimes(1)
+    expect(ctx.client.tui.showToast).toHaveBeenCalledTimes(1)
+    expect(logMock).toHaveBeenCalledWith(
+      "[preemptive-compaction] Detected post-compaction no-text tail pattern",
+      {
+        sessionID,
+        streak: 3,
+      },
+    )
+  })
+
+  it("resets no-text streak when assistant emits text content", async () => {
+    const ctx = createMockCtx()
+    const hook = createPreemptiveCompactionHook(ctx as never, {} as never)
+    const sessionID = "ses_tail_reset"
+
+    await hook.event({
+      event: {
+        type: "session.compacted",
+        properties: { sessionID },
+      },
+    })
+
+    await hook.event(buildAssistantUpdate({
+      sessionID,
+      id: "msg_1",
+      parts: [{ type: "step-start" }, { type: "step-finish" }],
+    }))
+
+    await hook.event(buildAssistantUpdate({
+      sessionID,
+      id: "msg_2",
+      parts: [{ type: "text", text: "Recovered response" }],
+    }))
+
+    await hook.event(buildAssistantUpdate({
+      sessionID,
+      id: "msg_3",
+      parts: [{ type: "step-start" }, { type: "step-finish" }],
+    }))
+
+    await hook.event(buildAssistantUpdate({
+      sessionID,
+      id: "msg_4",
+      parts: [{ type: "step-start" }, { type: "step-finish" }],
+    }))
+
+    expect(ctx.client.session.summarize).not.toHaveBeenCalled()
+  })
+})