chore: use bun

[nakasyou]

This PR switches the package manager used in this project to Bun.

Why migrate to Bun?

One reason for migrating is the faster installation speed, but that’s not the primary motivation. The main benefit of using Bun is that it helps save disk space. Yarn creates a node_modules directory for every workspace, even when packages share the same version. In contrast, Bun typically creates a node_modules directory only at the project root, significantly reducing disk space usage.

Addressing Version Mismatch Issues

There were issues where Bun caused version mismatches, leading to test failures.

These failing tests have been resolved in this PR. Most test failures stemmed from type mismatches. For example, the current version of Hono includes a TypeScript property, status, to improve user experience, which didn’t exist in older versions. Adding such TypeScript properties caused issues when test code in this project used Equal, as shown below:

type Actual = ExtractSchema<typeof route>
type Expected = {
  '/': {
    $post: {
      input: {}
      output: {}
    }
  }
}
type verify = Expect<Equals<Actual, Expected>>

In this PR, the issue is resolved by using expectTypeOf<Actual>().toMatchObjectType<Expected>(). This approach doesn’t require exact equality, only compatibility between types.

Additionally, with Bun, you can specify a particular version of Hono in devDependencies. If a different Hono version is listed in devDependencies, Bun creates a separate node_modules directory to maintain compatibility.

The Author Should Do the Following, if Applicable

• Add tests
• Run tests
• Run yarn changeset at the root of this repo and push the changeset
• Follow the contribution guide

[changeset-bot]

⚠️ No Changeset found

Latest commit: 53dfda6

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[nakasyou]

Duplicate #628