fix(talk): keep consult result truncation UTF-16 safe

Alix-007 · Alix-007 · commit b5813558e51f · 2026-07-07T11:07:02.000+08:00
diff --git a/src/talk/consult-question.test.ts b/src/talk/consult-question.test.ts
@@ -6,6 +6,22 @@ import {
   readSpeakableRealtimeVoiceToolResult,
 } from "./consult-question.js";
 
+function hasLoneSurrogate(value: string): boolean {
+  for (let index = 0; index < value.length; index += 1) {
+    const code = value.charCodeAt(index);
+    if (code >= 0xd800 && code <= 0xdbff) {
+      const next = value.charCodeAt(index + 1);
+      if (next < 0xdc00 || next > 0xdfff) {
+        return true;
+      }
+      index += 1;
+    } else if (code >= 0xdc00 && code <= 0xdfff) {
+      return true;
+    }
+  }
+  return false;
+}
+
 describe("realtime voice consult question helpers", () => {
   it("reads common provider question fields", () => {
     expect(readRealtimeVoiceConsultQuestion({ question: " check status " })).toBe("check status");
@@ -40,4 +56,15 @@ describe("realtime voice consult question helpers", () => {
       ),
     ).toBe("abcdefgh [truncated]");
   });
+
+  it("does not split a boundary emoji in truncated speakable text", () => {
+    const result = readSpeakableRealtimeVoiceToolResult(
+      { text: `${"a".repeat(7)}😀${"b".repeat(20)}` },
+      { maxChars: 23 },
+    );
+
+    expect(result).toBe(`${"a".repeat(7)} [truncated]`);
+    expect(result).toContain("[truncated]");
+    expect(hasLoneSurrogate(result ?? "")).toBe(false);
+  });
 });
diff --git a/src/talk/consult-question.ts b/src/talk/consult-question.ts
@@ -5,6 +5,7 @@
  * pulling human-readable questions/results out of provider-owned payloads.
  */
 import { normalizeOptionalString } from "@openclaw/normalization-core/string-coerce";
+import { truncateUtf16Safe } from "@openclaw/normalization-core/utf16-slice";
 import { readTrimmedStringAlias } from "../utils/string-readers.js";
 
 const REALTIME_VOICE_CONSULT_QUESTION_STOPWORDS = new Set([
@@ -166,5 +167,5 @@ function limitSpeakableRealtimeVoiceToolResult(
   }
   // Reserve space for the marker so callers can keep audio replies under a
   // provider or UX limit without losing the truncation signal.
-  return `${trimmed.slice(0, Math.max(0, maxChars - 16)).trimEnd()} [truncated]`;
+  return `${truncateUtf16Safe(trimmed, Math.max(0, maxChars - 16)).trimEnd()} [truncated]`;
 }

Original file line number	Diff line number	Diff line change
`@@ -5,6 +5,7 @@`
`5`	`5`	`* pulling human-readable questions/results out of provider-owned payloads.`
`6`	`6`	`*/`
`7`	`7`	`import { normalizeOptionalString } from "@openclaw/normalization-core/string-coerce";`
	`8`	`+import { truncateUtf16Safe } from "@openclaw/normalization-core/utf16-slice";`
`8`	`9`	`import { readTrimmedStringAlias } from "../utils/string-readers.js";`
`9`	`10`
`10`	`11`	`const REALTIME_VOICE_CONSULT_QUESTION_STOPWORDS = new Set([`
`@@ -166,5 +167,5 @@ function limitSpeakableRealtimeVoiceToolResult(`
`166`	`167`	`}`
`167`	`168`	`// Reserve space for the marker so callers can keep audio replies under a`
`168`	`169`	`// provider or UX limit without losing the truncation signal.`
`169`		- return `${trimmed.slice(0, Math.max(0, maxChars - 16)).trimEnd()} [truncated]`;
	`170`	+ return `${truncateUtf16Safe(trimmed, Math.max(0, maxChars - 16)).trimEnd()} [truncated]`;
`170`	`171`	`}`