Fix Changesets prerelease publishing

scripts/release-channel.mjs

@@ -20,13 +20,15 @@ run(['pre', 'enter', channel]);
 run(['version']);
 
 if (publish) {
-  const result = spawnSync('npx', ['changeset', 'publish', '--tag', channel], {
+  // Changesets reads the active prerelease tag from .changeset/pre.json.
+  // Passing --tag in pre mode is rejected and prevents trusted CI from publishing.
+  const result = spawnSync('npx', ['changeset', 'publish'], {
     cwd: root,
     encoding: 'utf8',
     stdio: 'inherit',
     env: { ...process.env, NPM_CONFIG_PROVENANCE: 'true', NPM_CONFIG_ACCESS: 'public' }
   });
-  if (result.status !== 0) throw new Error(`npx changeset publish --tag ${channel} failed`);
+  if (result.status !== 0) throw new Error(`npx changeset publish failed for prerelease channel ${channel}`);
 } else {
   console.log(`Prepared ${channel} pre-release versions. Review the versioned files, then publish from trusted CI with --publish.`);
 }

tests/unit/release-channel.test.ts

@@ -0,0 +1,50 @@
+import { chmodSync, mkdirSync, mkdtempSync, readFileSync, rmSync, writeFileSync } from 'node:fs';
+import os from 'node:os';
+import path from 'node:path';
+import { spawnSync } from 'node:child_process';
+import { describe, expect, it } from 'vitest';
+
+describe('release-channel', () => {
+  it('publishes from Changesets prerelease mode without passing a custom tag', () => {
+    const temporaryRoot = mkdtempSync(path.join(os.tmpdir(), 'webaseui-release-channel-'));
+    const binDirectory = path.join(temporaryRoot, 'bin');
+    const logPath = path.join(temporaryRoot, 'calls.jsonl');
+    const npxPath = path.join(binDirectory, 'npx');
+
+    try {
+      mkdirSync(binDirectory);
+      writeFileSync(
+        npxPath,
+        '#!/usr/bin/env node\n' +
+          "const fs = require('node:fs');\n" +
+          "fs.appendFileSync(process.env.WEBASEUI_RELEASE_TEST_LOG, JSON.stringify({ args: process.argv.slice(2), provenance: process.env.NPM_CONFIG_PROVENANCE, access: process.env.NPM_CONFIG_ACCESS }) + '\\n');\n"
+      );
+      chmodSync(npxPath, 0o755);
+
+      const result = spawnSync(process.execPath, ['scripts/release-channel.mjs', 'next', '--publish'], {
+        cwd: path.resolve(import.meta.dirname, '../..'),
+        encoding: 'utf8',
+        env: {
+          ...process.env,
+          CI: 'true',
+          PATH: binDirectory + ':' + (process.env.PATH ?? ''),
+          WEBASEUI_RELEASE_TEST_LOG: logPath
+        }
+      });
+
+      expect(result.status, result.stderr).toBe(0);
+      const calls = readFileSync(logPath, 'utf8')
+        .trim()
+        .split('\n')
+        .map((line) => JSON.parse(line));
+      expect(calls.map(({ args }) => args)).toEqual([
+        ['changeset', 'pre', 'enter', 'next'],
+        ['changeset', 'version'],
+        ['changeset', 'publish']
+      ]);
+      expect(calls[2]).toMatchObject({ provenance: 'true', access: 'public' });
+    } finally {
+      rmSync(temporaryRoot, { recursive: true, force: true });
+    }
+  });
+});