Migrate to Shoehorn
Why shoehorn?
shoehorn 允许你在 tests 中传入 partial data，同时保持 TypeScript 满意。它用 type-safe alternatives 替换 as assertions。
只用于 test code。 永远不要在 production code 中使用 shoehorn。
Tests 中 as 的问题：
- 经过训练，不去使用它
- 必须手动指定 target type
- 对故意错误的数据需要 double-as（
as unknown as Type）
Install
bashnpm i @total-typescript/shoehorn
Migration patterns
Large objects with few needed properties
Before:
tstype Request = { body: { id: string }; headers: Record<string, string>; cookies: Record<string, string>; // ...20 more properties }; it("gets user by id", () => { // Only care about body.id but must fake entire Request getUser({ body: { id: "123" }, headers: {}, cookies: {}, // ...fake all 20 properties }); });
After:
tsimport { fromPartial } from "@total-typescript/shoehorn"; it("gets user by id", () => { getUser( fromPartial({ body: { id: "123" }, }), ); });
as Type → fromPartial()
Before:
tsgetUser({ body: { id: "123" } } as Request);
After:
tsimport { fromPartial } from "@total-typescript/shoehorn"; getUser(fromPartial({ body: { id: "123" } }));
as unknown as Type → fromAny()
Before:
tsgetUser({ body: { id: 123 } } as unknown as Request); // wrong type on purpose
After:
tsimport { fromAny } from "@total-typescript/shoehorn"; getUser(fromAny({ body: { id: 123 } }));
When to use each
| Function | Use case |
|---|---|
fromPartial() | 传入仍能 type-check 的 partial data |
fromAny() | 传入故意错误的数据（保留 autocomplete） |
fromExact() | 强制 full object（之后可换成 fromPartial） |
Workflow
-
Gather requirements — 询问用户：
- 哪些 test files 中的
asassertions 造成问题？ - 是否在处理大型 objects，但只关心部分 properties？
- 是否需要传入故意错误的数据来测试 error paths？
- 哪些 test files 中的
-
Install and migrate：
- Install:
npm i @total-typescript/shoehorn - 查找 test files 中的
asassertions:grep -r " as [A-Z]" --include="*.test.ts" --include="*.spec.ts" - 用
fromPartial()替换as Type - 用
fromAny()替换as unknown as Type - 添加来自
@total-typescript/shoehorn的 imports - 运行 type check 验证
- Install:
