✨ feat(vscode): 摘修复识别 alembic 迁移，接不上发布分支链的高亮禁用不可摘

按 writing-alembic-migrations 的规矩判断：迁移的前任必须已在发布分支上，
且发布分支上该前任不能已有别的后继；根迁移接不上已有链、删迁移会断链也不可摘。
列表里带迁移的提交打「迁移」角标，不可摘的高亮警告色、禁用勾选并写明原因；
确认接口再校验一遍，绕过前端也摘不进去。

Claude-Session: https://claude.ai/code/session_01QWxLb6X8Vd2G5vHnp6R7qm

vscode/test/git/release.test.ts

@@ -1,5 +1,5 @@
 import { execFileSync } from 'node:child_process'
-import { existsSync, promises as fsp, rmSync, writeFileSync } from 'node:fs'
+import { existsSync, promises as fsp, mkdirSync, rmSync, writeFileSync } from 'node:fs'
 import * as os from 'node:os'
 import * as path from 'node:path'
 import { afterEach, describe, expect, it } from 'vitest'
@@ -12,6 +12,7 @@ import {
   listReleaseBranches,
   listUnreleasedCommits,
   normalizeReleasePrefix,
+  parseAlembicRevision,
   parseGiteaMergeSubject,
   pickCurrentRelease,
   todayReleaseBranch,
@@ -39,6 +40,10 @@ function commit(cwd: string, file: string, content: string, msg: string): string
   git(cwd, ['commit', '-m', msg])
   return git(cwd, ['rev-parse', 'HEAD'])
 }
+function migration(cwd: string, file: string, rev: string, down: string | null, msg: string): string {
+  mkdirSync(path.dirname(path.join(cwd, file)), { recursive: true })
+  return commit(cwd, file, `revision = '${rev}'\ndown_revision = ${down === null ? 'None' : `'${down}'`}\n`, msg)
+}
 let fx: Fx | undefined
 afterEach(() => {
   if (fx)
@@ -66,6 +71,13 @@ describe('纯函数', () => {
     })
     expect(parseGiteaMergeSubject('fix: no merge')).toBeUndefined()
   })
+  it('parseAlembicRevision 认裸赋值、带类型标注、元组和 None', () => {
+    expect(parseAlembicRevision('revision = \'a1\'\ndown_revision = \'a0\'\n')).toEqual({ revision: 'a1', downRevisions: ['a0'] })
+    expect(parseAlembicRevision('revision: str = "a1"\ndown_revision: Union[str, None] = "a0"\nbranch_labels = None\n')).toEqual({ revision: 'a1', downRevisions: ['a0'] })
+    expect(parseAlembicRevision('revision = \'m\'\ndown_revision = (\'a\', \'b\')\n')).toEqual({ revision: 'm', downRevisions: ['a', 'b'] })
+    expect(parseAlembicRevision('revision: str = \'root\'\ndown_revision: Union[str, None] = None\n')).toEqual({ revision: 'root', downRevisions: [] })
+    expect(parseAlembicRevision('print(1)\n')).toBeUndefined()
+  })
   it('groupCommitsByPr 按 Gitea 给的 pr 号分组，说明里没有 Closes 也能归组', () => {
     const groups = groupCommitsByPr([
       { sha: '3e519ea', subject: 'fix(admin): 会员档位隐藏', author: 'chehongweo', date: '2026-08-31', body: '', pr: 260, prTitle: '连续包月会员订阅体系' },
@@ -237,4 +249,37 @@ describe('集成', () => {
     const list = await listUnreleasedCommits({ cwd: fx.repo, devBranch: 'main', current: 'release/2026-08-31' })
     expect(list.map(c => c.subject)).toEqual(['fix(jobs): 一次性命令收口'])
   })
+  it('带迁移的提交：前任在发布分支上才能摘，前任缺失的标不可摘，不带迁移的不打标', async () => {
+    fx = await setup()
+    migration(fx.peer, 'alembic/versions/0001_init.py', '0001', null, 'feat: init schema')
+    git(fx.peer, ['push', 'origin', 'main'])
+    await cutRelease({ cwd: fx.repo, devBranch: 'main', branch: 'release/2026-08-31' })
+    migration(fx.peer, 'alembic/versions/0002_x.py', '0002', '0001', 'feat: m2')
+    migration(fx.peer, 'alembic/versions/0003_y.py', '0003', '0002', 'feat: m3')
+    commit(fx.peer, 'b.txt', 'b', 'fix: plain')
+    git(fx.peer, ['push', 'origin', 'main'])
+    git(fx.repo, ['fetch', 'origin'])
+    const list = await listUnreleasedCommits({ cwd: fx.repo, devBranch: 'main', current: 'release/2026-08-31' })
+    expect(list.map(c => c.subject)).toEqual(['fix: plain', 'feat: m3', 'feat: m2'])
+    expect(list[0].migration).toBeUndefined()
+    expect(list[1].migration?.files).toEqual(['alembic/versions/0003_y.py'])
+    expect(list[1].migration?.blocked).toContain('0002')
+    expect(list[2].migration).toEqual({ files: ['alembic/versions/0002_x.py'] })
+  })
+  it('发布分支上同一前任已有后继 → 多 head，不可摘', async () => {
+    fx = await setup()
+    migration(fx.peer, 'alembic/versions/0001_init.py', '0001', null, 'feat: init schema')
+    git(fx.peer, ['push', 'origin', 'main'])
+    await cutRelease({ cwd: fx.repo, devBranch: 'main', branch: 'release/2026-08-31' })
+    migration(fx.peer, 'alembic/versions/0002_x.py', '0002', '0001', 'feat: m2')
+    git(fx.peer, ['push', 'origin', 'main'])
+    git(fx.peer, ['fetch'])
+    git(fx.peer, ['checkout', '-b', 'release/2026-08-31', 'origin/release/2026-08-31'])
+    migration(fx.peer, 'alembic/versions/0002_hotfix.py', '0002b', '0001', 'fix: hotfix schema')
+    git(fx.peer, ['push', 'origin', 'release/2026-08-31'])
+    git(fx.repo, ['fetch', 'origin'])
+    const list = await listUnreleasedCommits({ cwd: fx.repo, devBranch: 'main', current: 'release/2026-08-31' })
+    expect(list.map(c => c.subject)).toEqual(['feat: m2'])
+    expect(list[0].migration?.blocked).toContain('多个 head')
+  })
 })