fix(objectql): apply defaultValue on explicit null at insert (#2706)

[baozhoutao]

背景

修复 #2706 中归属本仓库(objectql)的子问题。

排查结论

• Add metamodel interfaces for ObjectQL/ObjectUI contract #1 解析顺序晚于 beforeInsert hook — 已由 [objectql] 字段 defaultValue 解析晚于 beforeInsert hook,派生字段 hook 读到 null #2703 / fix(data): resolve field defaultValues before beforeInsert hook (#2703) #2748 修复(applyFieldDefaults 现已在 beforeInsert 之前执行),含回归测试,本次无需再动。
• ✨ Set up Copilot instructions #2 显式 null 不回填 — 本 PR 修复。
• Implement ObjectStack protocol specification with Zod schemas and TypeScript interfaces #3 创建表单不预填 current_user — 归属 objectui,本仓库不涉及。

改动

applyFieldDefaults 原判据为 out[f.name] !== undefined,只有"省略"字段才回填 default;表单把未选控件序列化成显式 null 时会落库 null(current_user 令牌与静态默认都不生效)。

• 判据改为 out[f.name] != null:insert 时"省略"与"显式 null"一视同仁,都视为"未提供值"并回填 default。
• 空串 '' 仍视为真实值,不覆盖。
• 仅影响 insert 路径:applyFieldDefaults 只在 insert() 调用,update() 从不调用它,因此 update 的"置 null"语义完全不受影响。
• 更新函数文档注释,明确 omitted / explicit null 均按"未提供"处理的语义。

测试

新增两条回归测试(engine.test.ts):

• 显式 owner:null, status:null → 回填 current_user + 静态默认;
• 显式 status:'' → 保留空串不覆盖。

packages/objectql 全部 48 条测试通过。

Refs #2706(本仓库子项 #1/#2;#3 归 objectui,保留 issue 开启)

[vercel]

The latest updates on your projects. Learn more about Vercel for GitHub.

Project	Deployment	Actions	Updated (UTC)
spec	Ready	Preview, Comment	Jul 13, 2026 3:07am

[github-actions]

📓 Docs Drift Check

This PR changes 1 package(s): @objectstack/objectql.

13 hand-written doc(s) reference the affected code and may need an implementation-accuracy re-verification:

• content/docs/concepts/metadata-lifecycle.mdx (via @objectstack/objectql)
• content/docs/data-modeling/formulas.mdx (via packages/objectql)
• content/docs/deployment/migration-from-objectql.mdx (via @objectstack/objectql)
• content/docs/deployment/vercel.mdx (via @objectstack/objectql)
• content/docs/kernel/services-checklist.mdx (via @objectstack/objectql)
• content/docs/kernel/services.mdx (via @objectstack/objectql)
• content/docs/permissions/authentication.mdx (via @objectstack/objectql)
• content/docs/plugins/index.mdx (via @objectstack/objectql)
• content/docs/plugins/packages.mdx (via @objectstack/objectql)
• content/docs/protocol/objectos/index.mdx (via @objectstack/objectql)
• content/docs/protocol/objectql/state-machine.mdx (via @objectstack/objectql)
• content/docs/releases/implementation-status.mdx (via @objectstack/objectql)
• content/docs/releases/v9.mdx (via @objectstack/objectql)

Advisory only. To re-verify, run the docs-accuracy-audit workflow scoped to these files:
node scripts/docs-audit/affected-docs.mjs origin/main → pass the list as args.docs.