fix(signal): surface daemon errors split across output chunks (#104152)

* fix(signal): preserve daemon log lines across chunks

* test(signal): cover split utf-8 daemon output

---------

Co-authored-by: Peter Steinberger <steipete@gmail.com>

extensions/signal/src/daemon.test.ts

@@ -1,6 +1,8 @@
 // Signal tests cover daemon plugin behavior.
+import { once } from "node:events";
 import os from "node:os";
 import path from "node:path";
+import { PassThrough } from "node:stream";
 import { describe, expect, it } from "vitest";
 import { testApi } from "./daemon.js";
 
@@ -45,4 +47,34 @@ describe("signal daemon log classification", () => {
     expect(testApi.classifySignalCliLogLine("ERROR DaemonCommand - startup failed")).toBe("error");
     expect(testApi.classifySignalCliLogLine("SEVERE Manager - database exception")).toBe("error");
   });
+
+  it("preserves log lines and UTF-8 across output chunk boundaries", async () => {
+    const stream = new PassThrough();
+    const logs: string[] = [];
+    const errors: string[] = [];
+    testApi.bindSignalCliOutput({
+      stream,
+      log: (message) => logs.push(message),
+      error: (message) => errors.push(message),
+    });
+
+    const ended = once(stream, "end");
+    stream.write(Buffer.from("ER"));
+    stream.write(
+      Buffer.from("ROR DaemonCommand - startup failed\r\nWARN Manager - retrying\npartial"),
+    );
+    stream.write(" warning\n");
+    const utf8Line = Buffer.from("INFO Manager - café ready");
+    const splitCodePointAt = utf8Line.indexOf(0xc3) + 1;
+    stream.write(utf8Line.subarray(0, splitCodePointAt));
+    stream.end(utf8Line.subarray(splitCodePointAt));
+    await ended;
+
+    expect(errors).toEqual(["signal-cli: ERROR DaemonCommand - startup failed"]);
+    expect(logs).toEqual([
+      "signal-cli: WARN Manager - retrying",
+      "signal-cli: partial warning",
+      "signal-cli: INFO Manager - café ready",
+    ]);
+  });
 });

extensions/signal/src/daemon.ts

@@ -2,6 +2,7 @@
 import { spawn } from "node:child_process";
 import os from "node:os";
 import path from "node:path";
+import { createInterface } from "node:readline";
 import type { RuntimeEnv } from "openclaw/plugin-sdk/runtime-env";
 
 type SignalDaemonOpts = {
@@ -63,14 +64,18 @@ function bindSignalCliOutput(params: {
   log: (message: string) => void;
   error: (message: string) => void;
 }): void {
-  params.stream?.on("data", (data) => {
-    for (const line of data.toString().split(/\r?\n/)) {
-      const kind = classifySignalCliLogLine(line);
-      if (kind === "log") {
-        params.log(`signal-cli: ${line.trim()}`);
-      } else if (kind === "error") {
-        params.error(`signal-cli: ${line.trim()}`);
-      }
+  if (!params.stream) {
+    return;
+  }
+  // Process pipe chunks can split both log lines and UTF-8 code points. Readline owns that
+  // framing so classification sees complete text, including the final unterminated line.
+  const lines = createInterface({ input: params.stream });
+  lines.on("line", (line) => {
+    const kind = classifySignalCliLogLine(line);
+    if (kind === "log") {
+      params.log(`signal-cli: ${line.trim()}`);
+    } else if (kind === "error") {
+      params.error(`signal-cli: ${line.trim()}`);
     }
   });
 }
@@ -175,6 +180,7 @@ export function spawnSignalDaemon(opts: SignalDaemonOpts): SignalDaemonHandle {
 }
 
 export const testApi = {
+  bindSignalCliOutput,
   buildDaemonArgs,
   classifySignalCliLogLine,
   resolveSignalCliConfigPath,