migrate-to-shoehorn

Q: How do I install migrate-to-shoehorn?

Run npx skills add https://github.com/tt-a1i/matt-skills-with-to-goal --skill migrate-to-shoehorn in your project. The skills CLI detects the agents you use and copies the skill into the right folder. For Claude Code you can also place the skill folder at ~/.claude/skills/migrate-to-shoehorn/ (personal) or .claude/skills/migrate-to-shoehorn/ (project).

by tt-a1iTesting & QA

Migrate test files from as type assertions to @total-typescript/shoehorn. Use when user mentions shoehorn, wants to replace as in tests, or needs partial test data.

Installs: 96
Last 24h: —
Trending rank: —
Security: Not audited

Install

Works with every agent the skills CLI supports.

npx skills add https://github.com/tt-a1i/matt-skills-with-to-goal --skill migrate-to-shoehorn

01
Install
Run the command in your project. The CLI asks which agents to install for.
02
Describe the task
Ask your agent for something this skill covers. It loads migrate-to-shoehorn automatically when relevant.
03
Review the result
The agent follows the SKILL.md steps, scripts and references bundled with the skill.

SKILL.md

The instructions your agent reads when the skill is triggered.

Migrate to Shoehorn

Why shoehorn?

shoehorn lets you pass partial data in tests while keeping TypeScript happy. It replaces as assertions with type-safe alternatives.

Test code only. Never use shoehorn in production code.

Problems with as in tests:

Trained not to use it
Must manually specify target type
Double-as (as unknown as Type) for intentionally wrong data

Install

npm i @total-typescript/shoehorn

Migration patterns

Large objects with few needed properties

Before:

type 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:

import { fromPartial } from "@total-typescript/shoehorn";

it("gets user by id", () => {
  getUser(
    fromPartial({
      body: { id: "123" },
    }),
  );
});

`as Type` → `fromPartial()`

Before:

getUser({ body: { id: "123" } } as Request);

After:

import { fromPartial } from "@total-typescript/shoehorn";

getUser(fromPartial({ body: { id: "123" } }));

`as unknown as Type` → `fromAny()`

Before:

getUser({ body: { id: 123 } } as unknown as Request); // wrong type on purpose

After:

import { fromAny } from "@total-typescript/shoehorn";

getUser(fromAny({ body: { id: 123 } }));

When to use each

Function	Use case
`fromPartial()`	Pass partial data that still type-checks
`fromAny()`	Pass intentionally wrong data (keeps autocomplete)
`fromExact()`	Force full object (swap with fromPartial later)

Workflow

Gather requirements - ask user:
- What test files have as assertions causing problems?
- Are they dealing with large objects where only some properties matter?
- Do they need to pass intentionally wrong data for error testing?
Install and migrate:
- Install: npm i @total-typescript/shoehorn
- Find test files with as assertions: grep -r " as [A-Z]" --include="*.test.ts" --include="*.spec.ts"
- Replace as Type with fromPartial()
- Replace as unknown as Type with fromAny()
- Add imports from @total-typescript/shoehorn
- Run type check to verify

FAQ

What does the migrate-to-shoehorn skill do?

Migrate test files from as type assertions to @total-typescript/shoehorn. Use when user mentions shoehorn, wants to replace as in tests, or needs partial test data.

How do I install migrate-to-shoehorn?

Run npx skills add https://github.com/tt-a1i/matt-skills-with-to-goal --skill migrate-to-shoehorn in your project. The skills CLI detects the agents you use and copies the skill into the right folder. For Claude Code you can also place the skill folder at ~/.claude/skills/migrate-to-shoehorn/ (personal) or .claude/skills/migrate-to-shoehorn/ (project).

Which AI agents can use migrate-to-shoehorn?

Any agent that supports the open Agent Skills format (a folder with a SKILL.md file), including Claude Code, Codex, Cursor, GitHub Copilot, Gemini CLI, Windsurf, Cline, OpenCode and more.

Is migrate-to-shoehorn safe to install?

No partner security audit is available yet. Skills can run commands and scripts, so read the SKILL.md and any bundled files before installing.

Who maintains migrate-to-shoehorn?

It is published by tt-a1i in tt-a1i/matt-skills-with-to-goal. It has 96 recorded installs.