fix(cli): avoid splitting emoji when truncating output

src/commands/careers/apply.ts

@@ -8,6 +8,7 @@ import { buildHelpText } from '../../lib/help-text';
 import { outputError, outputResult } from '../../lib/output';
 import { cancelAndExit, pickItem } from '../../lib/prompts';
 import { withSpinner } from '../../lib/spinner';
+import { truncate } from '../../lib/truncate';
 import { isInteractive } from '../../lib/tty';
 import { COUNTRY_NAMES } from './countries';
 import { type Career, type CareerField, careerPickerConfig } from './utils';
@@ -334,7 +335,7 @@ async function confirmSubmission(
             ? 'No'
             : value
         : value;
-    return `${label}: ${truncate(display, 80)}`;
+    return `${label}: ${truncate(display.replace(/\s+/g, ' ').trim(), 80)}`;
   });
   lines.push(`Resume: ${basename(resumePath)}`);
 
@@ -346,13 +347,6 @@ async function confirmSubmission(
   }
 }
 
-function truncate(value: string, max: number): string {
-  const singleLine = value.replace(/\s+/g, ' ').trim();
-  return singleLine.length > max
-    ? `${singleLine.slice(0, max - 3)}...`
-    : singleLine;
-}
-
 function readResume(
   resumePath: string,
   globalOpts: GlobalOpts,

src/commands/emails/list.ts

@@ -8,6 +8,7 @@ import {
   printPaginationHint,
 } from '../../lib/pagination';
 import { renderTable } from '../../lib/table';
+import { truncate } from '../../lib/truncate';
 
 type SentEmail = {
   id: string;
@@ -22,9 +23,8 @@ type SentEmail = {
 function renderSentEmailsTable(emails: SentEmail[]): string {
   const rows = emails.map((e) => {
     const to = e.to.join(', ');
-    const toStr = to.length > 40 ? `${to.slice(0, 37)}...` : to;
-    const subject =
-      e.subject.length > 50 ? `${e.subject.slice(0, 47)}...` : e.subject;
+    const toStr = truncate(to, 40);
+    const subject = truncate(e.subject, 50);
     return [e.from, toStr, subject, e.last_event ?? '—', e.created_at, e.id];
   });
   return renderTable(

src/commands/emails/receiving/get.ts

@@ -3,6 +3,7 @@ import { runGet } from '../../../lib/actions';
 import type { GlobalOpts } from '../../../lib/client';
 import { buildHelpText } from '../../../lib/help-text';
 import { pickId } from '../../../lib/prompts';
+import { truncate } from '../../../lib/truncate';
 import { receivedEmailPickerConfig } from './utils';
 
 export const getReceivingCommand = new Command('get')
@@ -40,10 +41,7 @@ export const getReceivingCommand = new Command('get')
             console.log(`Files:   ${data.attachments.length} attachment(s)`);
           }
           if (data.text) {
-            const snippet =
-              data.text.length > 200
-                ? `${data.text.slice(0, 197)}...`
-                : data.text;
+            const snippet = truncate(data.text, 200);
             console.log(`${snippet}`);
           } else if (data.html) {
             console.log(

src/commands/emails/receiving/listen.ts

@@ -8,6 +8,7 @@ import { buildHelpText } from '../../../lib/help-text';
 import { errorMessage, outputError } from '../../../lib/output';
 import { safeTerminalText } from '../../../lib/safe-terminal-text';
 import { createSpinner } from '../../../lib/spinner';
+import { truncate } from '../../../lib/truncate';
 import { isInteractive } from '../../../lib/tty';
 import { withRetry } from '../../../lib/with-retry';
 import { type BoundedSet, createBoundedSet } from '../../../utils/bounded-set';
@@ -29,8 +30,7 @@ const displayEmail = (email: ListReceivingEmail, jsonMode: boolean): void => {
     const to = email.to.map(safeTerminalText).join(', ');
     const ts = pc.dim(`[${timestamp()}]`);
     const rawSubject = safeTerminalText(email.subject);
-    const subject =
-      rawSubject.length > 50 ? `${rawSubject.slice(0, 47)}...` : rawSubject;
+    const subject = truncate(rawSubject, 50);
     const from = safeTerminalText(email.from);
     const id = safeTerminalText(email.id);
     process.stderr.write(

src/commands/emails/receiving/utils.ts

@@ -1,6 +1,7 @@
 import type { ListReceivingEmail } from 'resend';
 import type { PickerConfig } from '../../../lib/prompts';
 import { renderTable } from '../../../lib/table';
+import { truncate } from '../../../lib/truncate';
 
 export const receivedEmailPickerConfig: PickerConfig<{
   id: string;
@@ -34,9 +35,8 @@ export function renderReceivingEmailsTable(
 ): string {
   const rows = emails.map((e) => {
     const to = e.to.join(', ');
-    const toStr = to.length > 40 ? `${to.slice(0, 37)}...` : to;
-    const subject =
-      e.subject.length > 50 ? `${e.subject.slice(0, 47)}...` : e.subject;
+    const toStr = truncate(to, 40);
+    const subject = truncate(e.subject, 50);
     return [e.from, toStr, subject, e.created_at, e.id];
   });
   return renderTable(

src/commands/templates/get.ts

@@ -3,6 +3,7 @@ import { runGet } from '../../lib/actions';
 import type { GlobalOpts } from '../../lib/client';
 import { buildHelpText } from '../../lib/help-text';
 import { pickId } from '../../lib/prompts';
+import { truncate } from '../../lib/truncate';
 import { templatePickerConfig } from './utils';
 
 export const getTemplateCommand = new Command('get')
@@ -45,10 +46,7 @@ export const getTemplateCommand = new Command('get')
             console.log(`Reply-To: ${data.reply_to.join(', ')}`);
           }
           if (data.html) {
-            const snippet =
-              data.html.length > 200
-                ? `${data.html.slice(0, 197)}...`
-                : data.html;
+            const snippet = truncate(data.html, 200);
             console.log(`HTML: ${snippet}`);
           }
           if (data.variables?.length) {

src/commands/webhooks/events/utils.ts

@@ -4,6 +4,7 @@ import type {
 } from 'resend';
 import type { PickerConfig } from '../../../lib/prompts';
 import { renderTable } from '../../../lib/table';
+import { truncate } from '../../../lib/truncate';
 
 export function webhookEventPickerConfig(
   webhookId: string,
@@ -40,7 +41,7 @@ export function renderWebhookEventAttemptsTable(
     return [
       String(a.http_status_code),
       a.sent_at,
-      response.length > 60 ? `${response.slice(0, 57)}...` : response,
+      truncate(response, 60),
       a.id,
     ];
   });

src/commands/webhooks/utils.ts

@@ -1,6 +1,7 @@
 import type { Webhook, WebhookEvent } from 'resend';
 import type { PickerConfig } from '../../lib/prompts';
 import { renderTable } from '../../lib/table';
+import { truncate } from '../../lib/truncate';
 
 export const ALL_WEBHOOK_EVENTS: WebhookEvent[] = [
   'email.sent',
@@ -49,9 +50,7 @@ export const webhookPickerConfig: PickerConfig<{
 export function renderWebhooksTable(webhooks: Webhook[]): string {
   const rows = webhooks.map((w) => {
     const eventsStr = (w.events ?? []).join(', ');
-    const events =
-      eventsStr.length > 60 ? `${eventsStr.slice(0, 57)}...` : eventsStr;
-    return [w.endpoint, events, w.status, w.id];
+    return [w.endpoint, truncate(eventsStr, 60), w.status, w.id];
   });
   return renderTable(
     ['Endpoint', 'Events', 'Status', 'ID'],

src/lib/truncate.ts

@@ -0,0 +1,30 @@
+const ELLIPSIS = '...';
+
+const segmenter = new Intl.Segmenter(undefined, { granularity: 'grapheme' });
+
+/**
+ * Shorten `value` to at most `max` UTF-16 code units, ending in "..." when it
+ * is cut. Cuts on whole visible characters (graphemes), so emoji built from
+ * several characters (families, flags, skin tones) are kept or dropped whole
+ * instead of leaving a stray joiner, half a flag or a lone surrogate.
+ *
+ * When `max` is not larger than the ellipsis there is no room for it, so the
+ * value is hard-cut with `slice(0, max)`.
+ */
+export function truncate(value: string, max: number): string {
+  if (value.length <= max) {
+    return value;
+  }
+  if (max <= ELLIPSIS.length) {
+    return value.slice(0, max);
+  }
+  const budget = max - ELLIPSIS.length;
+  let end = 0;
+  for (const { segment } of segmenter.segment(value)) {
+    if (end + segment.length > budget) {
+      break;
+    }
+    end += segment.length;
+  }
+  return `${value.slice(0, end)}${ELLIPSIS}`;
+}

tests/commands/emails/receiving/list.test.ts

@@ -8,6 +8,7 @@ import {
   vi,
 } from 'vitest';
 import { listReceivingCommand } from '../../../../src/commands/emails/receiving/list';
+import { renderReceivingEmailsTable } from '../../../../src/commands/emails/receiving/utils';
 import {
   captureTestEnv,
   expectExit1,
@@ -17,6 +18,9 @@ import {
   setupOutputSpies,
 } from '../../../helpers';
 
+const LONE_SURROGATE =
+  /[\ud800-\udbff](?![\udc00-\udfff])|(?<![\ud800-\udbff])[\udc00-\udfff]/;
+
 const mockList = vi.fn(async () => ({
   data: {
     object: 'list' as const,
@@ -159,4 +163,24 @@ describe('emails receiving list command', () => {
     const output = errorSpy.mock.calls.map((c) => c[0]).join(' ');
     expect(output).toContain('list_error');
   });
+
+  it('does not leave a lone surrogate when truncating an emoji subject', () => {
+    const subject = `${'a'.repeat(46)}😀${'b'.repeat(10)}`;
+    const table = renderReceivingEmailsTable([
+      {
+        id: 'rcv_1',
+        to: ['inbox@example.com'],
+        from: 'sender@example.com',
+        subject,
+        created_at: '2026-02-18 12:00:00+00',
+        message_id: '<m@example.com>',
+        bcc: null,
+        cc: null,
+        reply_to: null,
+        attachments: [],
+      },
+    ]);
+    expect(table).not.toMatch(LONE_SURROGATE);
+    expect(table).toContain(`${'a'.repeat(46)}...`);
+  });
 });

tests/lib/truncate.test.ts

@@ -0,0 +1,63 @@
+import { describe, expect, it } from 'vitest';
+import { truncate } from '../../src/lib/truncate';
+
+const LONE_SURROGATE =
+  /[\ud800-\udbff](?![\udc00-\udfff])|(?<![\ud800-\udbff])[\udc00-\udfff]/;
+
+describe('truncate', () => {
+  it('returns the value unchanged when it fits', () => {
+    expect(truncate('hello', 5)).toBe('hello');
+    expect(truncate('', 5)).toBe('');
+  });
+
+  it('cuts to max characters including the ellipsis', () => {
+    const out = truncate('abcdefghij', 8);
+    expect(out).toBe('abcde...');
+    expect(out).toHaveLength(8);
+  });
+
+  it('does not split a surrogate pair at the cut point', () => {
+    // 46 characters, then an emoji whose high surrogate lands at index 46.
+    const value = `${'a'.repeat(46)}😀${'b'.repeat(10)}`;
+    const out = truncate(value, 50);
+    expect(out).toBe(`${'a'.repeat(46)}...`);
+    expect(out).not.toMatch(LONE_SURROGATE);
+  });
+
+  it('keeps a whole emoji that ends exactly at the cut point', () => {
+    const value = `${'a'.repeat(45)}😀${'b'.repeat(10)}`;
+    expect(truncate(value, 50)).toBe(`${'a'.repeat(45)}😀...`);
+  });
+
+  it('hard-cuts without an ellipsis when max is not larger than it', () => {
+    expect(truncate('abcdef', 2)).toBe('ab');
+    expect(truncate('abcdef', 3)).toBe('abc');
+    expect(truncate('abcdef', 0)).toBe('');
+    expect(truncate('abcdef', 4)).toBe('a...');
+  });
+
+  describe.each([
+    ['a family emoji', '👨‍👩‍👧'],
+    ['a flag', '🇺🇸'],
+    ['a skin-tone emoji', '👍🏽'],
+  ])('with %s at the cut point', (_name, emoji) => {
+    it.each([
+      // The emoji straddles the cut at max 50 (budget 47), at every offset
+      // from fully inside the budget to fully outside it.
+      ...Array.from(
+        { length: emoji.length + 1 },
+        (_, i) => 47 - emoji.length + i,
+      ),
+    ])('keeps it whole or drops it whole with %i leading characters', (lead) => {
+      const value = `${'a'.repeat(lead)}${emoji}${'b'.repeat(20)}`;
+      const out = truncate(value, 50);
+      expect(out).not.toMatch(LONE_SURROGATE);
+      expect(out.endsWith('...')).toBe(true);
+      const body = out.slice(0, -3);
+      const fits = lead + emoji.length <= 47;
+      expect(body).toBe(
+        fits ? `${'a'.repeat(lead)}${emoji}` : 'a'.repeat(lead),
+      );
+    });
+  });
+});