fix: keep compress blocks active across restarts when origin message is missing

compressMessageId (the assistant message executing compress) is marked
ignored/synthetic and never persisted, so after an opencode restart the
block was deactivated and the full original context was re-injected,
causing premature compression reminders. Fall back to anchorMessageId
(which persists): if the anchor exists, keep the block active so the
compressed summary keeps being injected into the LLM context.

Author: Neko-Yukari

lib/messages/sync.ts

@@ -43,10 +43,31 @@ export const syncCompressionBlocks = (
             messageIds.has(block.compressMessageId)
 
         if (!hasOriginMessage) {
-            block.active = false
-            block.deactivatedAt = now
+            // compressMessageId（执行压缩的 assistant 消息）可能因被 DCP 标记为
+            // ignored/synthetic 而从未持久化，重启后会缺失。此时只要锚点消息仍在，
+            // 压缩摘要依然有效，应保留 active 使摘要继续注入 LLM 上下文；
+            // 否则每次重启压缩都会失效，上下文重新膨胀导致频繁触发压缩提醒。
+            const hasAnchorMessage =
+                typeof block.anchorMessageId === "string" &&
+                block.anchorMessageId.length > 0 &&
+                messageIds.has(block.anchorMessageId)
+
+            if (!hasAnchorMessage) {
+                block.active = false
+                block.deactivatedAt = now
+                block.deactivatedByBlockId = undefined
+                missingOriginBlockIds.push(block.blockId)
+                continue
+            }
+
+            block.active = true
+            block.deactivatedAt = undefined
             block.deactivatedByBlockId = undefined
-            missingOriginBlockIds.push(block.blockId)
+            messagesState.activeBlockIds.add(block.blockId)
+            messagesState.activeByAnchorMessageId.set(block.anchorMessageId, block.blockId)
+            logger.warn("Compress block origin message missing; keeping active via anchor", {
+                blockId: block.blockId,
+            })
             continue
         }
 

tests/sync-blocks.test.ts

@@ -0,0 +1,208 @@
+import assert from "node:assert/strict"
+import test from "node:test"
+import { Logger } from "../lib/logger"
+import { createSessionState, type WithParts } from "../lib/state"
+import type { CompressionBlock } from "../lib/state"
+import { syncCompressionBlocks } from "../lib/messages/sync"
+import { prune } from "../lib/messages/prune"
+import type { PluginConfig } from "../lib/config"
+import { saveSessionState, loadSessionState } from "../lib/state/persistence"
+import { existsSync, rmSync, readFileSync } from "node:fs"
+import { join } from "node:path"
+
+function msg(id: string, role: "user" | "assistant" = "user"): WithParts {
+    return {
+        info: {
+            id,
+            role,
+            sessionID: "ses-sync-test",
+            time: { created: 1 },
+        },
+        parts: [
+            {
+                id: `${id}-part`,
+                messageID: id,
+                sessionID: "ses-sync-test",
+                type: "text" as const,
+                text: `content of ${id}`,
+            },
+        ],
+    } as unknown as WithParts
+}
+
+function buildBlock(
+    anchorMessageId: string,
+    compressMessageId: string,
+    rangeMessageIds: string[],
+    summary: string,
+): CompressionBlock {
+    return {
+        blockId: 1,
+        runId: 1,
+        active: true,
+        deactivatedByUser: false,
+        compressedTokens: 1000,
+        summaryTokens: summary.length,
+        mode: "range",
+        topic: "sync-test",
+        batchTopic: "sync-test",
+        startId: "m0001",
+        endId: "m0009",
+        anchorMessageId,
+        compressMessageId,
+        includedBlockIds: [],
+        consumedBlockIds: [],
+        parentBlockIds: [],
+        directMessageIds: rangeMessageIds,
+        directToolIds: [],
+        effectiveMessageIds: rangeMessageIds,
+        effectiveToolIds: [],
+        createdAt: 1,
+        summary,
+    }
+}
+
+function buildConfig(): PluginConfig {
+    return {
+        enabled: true,
+        debug: false,
+        pruneNotification: "off",
+        pruneNotificationType: "chat",
+        commands: { enabled: true, protectedTools: [] },
+        manualMode: { enabled: false, automaticStrategies: true },
+        turnProtection: { enabled: false, turns: 4 },
+        experimental: { allowSubAgents: false, customPrompts: false },
+        protectedFilePatterns: [],
+        compress: {
+            mode: "range",
+            permission: "allow",
+            showCompression: false,
+            summaryBuffer: true,
+            maxContextLimit: "85%",
+            minContextLimit: "60%",
+            nudgeFrequency: 5,
+            iterationNudgeThreshold: 15,
+            nudgeForce: "soft",
+            protectedTools: ["task"],
+            protectTags: false,
+            protectUserMessages: false,
+        },
+        strategies: {
+            deduplication: { enabled: true, protectedTools: [] },
+            purgeErrors: { enabled: false, turns: 4, protectedTools: [] },
+        },
+    }
+}
+
+test("syncCompressionBlocks keeps block active via anchor when compressMessageId is missing", () => {
+    const state = createSessionState()
+    const anchorMsgId = "msg-anchor"
+    const rangeMsgIds = ["msg-1", "msg-2", "msg-3"]
+    const messages = [msg(anchorMsgId), ...rangeMsgIds.map((id) => msg(id))]
+
+    // compressMessageId 指向不存在的消息（模拟被标记 ignored 未持久化）
+    const block = buildBlock(anchorMsgId, "msg-compress-missing", rangeMsgIds, "summary text")
+    state.prune.messages.blocksById.set(1, block)
+    for (const id of rangeMsgIds) {
+        state.prune.messages.byMessageId.set(id, { allBlockIds: [1], activeBlockIds: [1] })
+    }
+
+    syncCompressionBlocks(state, new Logger(false), messages)
+
+    assert.equal(block.active, true)
+    assert.equal(state.prune.messages.activeBlockIds.has(1), true)
+    assert.equal(state.prune.messages.activeByAnchorMessageId.get(anchorMsgId), 1)
+})
+
+test("syncCompressionBlocks still deactivates block when both origin and anchor are missing", () => {
+    const state = createSessionState()
+    const rangeMsgIds = ["msg-1"]
+    const messages = rangeMsgIds.map((id) => msg(id))
+
+    const block = buildBlock("msg-anchor-missing", "msg-compress-missing", rangeMsgIds, "summary")
+    state.prune.messages.blocksById.set(1, block)
+    state.prune.messages.byMessageId.set("msg-1", { allBlockIds: [1], activeBlockIds: [1] })
+
+    syncCompressionBlocks(state, new Logger(false), messages)
+
+    assert.equal(block.active, false)
+    assert.equal(state.prune.messages.activeBlockIds.has(1), false)
+})
+
+test("prune injects compressed summary into LLM context after sync keeps block active", () => {
+    const state = createSessionState()
+    const anchorMsgId = "msg-anchor"
+    const rangeMsgIds = ["msg-1", "msg-2", "msg-3"]
+    const summary = "[Compressed conversation section]\n压缩后的关键摘要内容。"
+    const messages = [msg(anchorMsgId), ...rangeMsgIds.map((id) => msg(id))]
+
+    const block = buildBlock(anchorMsgId, "msg-compress-missing", rangeMsgIds, summary)
+    state.prune.messages.blocksById.set(1, block)
+    for (const id of rangeMsgIds) {
+        state.prune.messages.byMessageId.set(id, { allBlockIds: [1], activeBlockIds: [1] })
+    }
+
+    syncCompressionBlocks(state, new Logger(false), messages)
+    prune(state, new Logger(false), buildConfig(), messages)
+
+    // 摘要必须实际注入（LLM 能读到被压缩的内容）
+    const joined = messages
+        .map((m) =>
+            (m.parts ?? [])
+                .map((p: any) => (typeof p.text === "string" ? p.text : ""))
+                .join(" "),
+        )
+        .join("\n")
+    assert.ok(
+        joined.includes("[Compressed conversation section]"),
+        `expected summary marker, got: ${joined.slice(0, 300)}`,
+    )
+    assert.ok(joined.includes("压缩后的关键摘要内容"), "summary content must reach the LLM")
+
+    // 范围内的原始消息被摘要替换（不发送原文）
+    for (const id of rangeMsgIds) {
+        assert.equal(
+            messages.some((m) => m.info.id === id),
+            false,
+            `compressed message ${id} should be removed`,
+        )
+    }
+    // 锚点消息保留
+    assert.ok(messages.some((m) => m.info.id === anchorMsgId))
+})
+
+test("modelContextLimit is persisted and restored across restarts", async () => {
+    // 回归：重启后第一轮 chat.message hook 先于 system.prompt hook 运行，
+    // modelContextLimit 若未持久化则阈值无法按百分比解析。
+    const sid = "ses-persist-roundtrip"
+    const filePath = join(
+        process.env.XDG_DATA_HOME || join(process.env.USERPROFILE || "", ".local", "share"),
+        "opencode",
+        "storage",
+        "plugin",
+        "dcp",
+        `${sid}.json`,
+    )
+    try {
+        const logger = new Logger(false)
+
+        const state = createSessionState()
+        state.sessionId = sid
+        state.modelContextLimit = 1000000 // 1M，如 deepseek-v4-flash / kimi k3
+        await saveSessionState(state, logger)
+
+        // 模拟重启：从磁盘加载（modelContextLimit 必须恢复）
+        const loaded = await loadSessionState(sid, logger)
+        assert.ok(loaded !== null)
+        assert.equal(loaded.modelContextLimit, 1000000)
+
+        // 持久化文件里确实包含该字段（而非仅内存）
+        assert.equal(existsSync(filePath), true)
+        const raw = JSON.parse(readFileSync(filePath, "utf-8"))
+        assert.equal(raw.modelContextLimit, 1000000)
+    } finally {
+        if (existsSync(filePath)) {
+            rmSync(filePath, { force: true })
+        }
+    }
+})