fix(discord): keep error body summaries UTF-16 safe

Alix-007 · Alix-007 · commit e72222e8c83b · 2026-07-07T11:00:52.000+08:00
diff --git a/extensions/discord/src/error-body.test.ts b/extensions/discord/src/error-body.test.ts
@@ -0,0 +1,30 @@
+// Discord tests cover error body summary behavior.
+import { describe, expect, it } from "vitest";
+import { summarizeDiscordResponseBody } from "./error-body.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;
+      continue;
+    }
+    if (code >= 0xdc00 && code <= 0xdfff) {
+      return true;
+    }
+  }
+  return false;
+}
+
+describe("summarizeDiscordResponseBody", () => {
+  it("keeps truncated summaries on a UTF-16 boundary", () => {
+    const summary = summarizeDiscordResponseBody(`${"a".repeat(239)}😀tail`);
+
+    expect(summary).toHaveLength(239);
+    expect(hasLoneSurrogate(summary ?? "")).toBe(false);
+  });
+});
diff --git a/extensions/discord/src/error-body.ts b/extensions/discord/src/error-body.ts
@@ -1,4 +1,6 @@
 // Discord plugin module implements error body behavior.
+import { truncateUtf16Safe } from "openclaw/plugin-sdk/text-utility-runtime";
+
 const DISCORD_RESPONSE_BODY_SUMMARY_MAX_CHARS = 240;
 
 export function summarizeDiscordResponseBody(
@@ -18,7 +20,7 @@ export function summarizeDiscordResponseBody(
   if (!summary) {
     return opts.emptyText;
   }
-  return summary.slice(0, DISCORD_RESPONSE_BODY_SUMMARY_MAX_CHARS);
+  return truncateUtf16Safe(summary, DISCORD_RESPONSE_BODY_SUMMARY_MAX_CHARS);
 }
 
 export function isDiscordHtmlResponseBody(body: string, contentType?: string | null): boolean {

Original file line number	Diff line number	Diff line change
`@@ -1,4 +1,6 @@`
`1`	`1`	`// Discord plugin module implements error body behavior.`
	`2`	`+import { truncateUtf16Safe } from "openclaw/plugin-sdk/text-utility-runtime";`
	`3`	`+`
`2`	`4`	`const DISCORD_RESPONSE_BODY_SUMMARY_MAX_CHARS = 240;`
`3`	`5`
`4`	`6`	`export function summarizeDiscordResponseBody(`
`@@ -18,7 +20,7 @@ export function summarizeDiscordResponseBody(`
`18`	`20`	`if (!summary) {`
`19`	`21`	`return opts.emptyText;`
`20`	`22`	`}`
`21`		`- return summary.slice(0, DISCORD_RESPONSE_BODY_SUMMARY_MAX_CHARS);`
	`23`	`+ return truncateUtf16Safe(summary, DISCORD_RESPONSE_BODY_SUMMARY_MAX_CHARS);`
`22`	`24`	`}`
`23`	`25`
`24`	`26`	`export function isDiscordHtmlResponseBody(body: string, contentType?: string \| null): boolean {`