feat(validator)!: warn when validator does not find a valid content type in the request

[EdamAme-x]

Related: #3707

The author should do the following, if applicable

• Add tests
• Run tests
• bun run format:fix && bun run lint:fix to format the code
• Add TSDoc/JSDoc to document the code

[EdamAme-x]

hi @Soviut

Combine middleware now handles multiple validator types well.
(This is a breaking change for validator, however, and will require a v5 release.)

[EdamAme-x]

E.x.

describe('JSON and FormData', () => {
  const app = new Hono()
  app.post(
    '/',
    some(
      validator('json', (value) => value),
      validator('form', (value) => value)
    ),
    async (c) => {
      const jsonData = c.req.valid('json')
      const formData = c.req.valid('form')
      return c.json({
        json: jsonData,
        form: formData,
      })
    }
  )

  it('Should validate a JSON request', async () => {
    const res = await app.request('/', {
      method: 'POST',
      body: JSON.stringify({ foo: 'bar' }),
      headers: {
        'Content-Type': 'application/json',
      },
    })
    expect(res.status).toBe(200)
    const data = await res.json()
    expect(data.json).toEqual({ foo: 'bar' })
  })

  it('Should validate a FormData request', async () => {
    const form = new FormData()
    form.append('foo', 'bar')
    const res = await app.request('/', {
      method: 'POST',
      body: form,
    })
    expect(res.status).toBe(200)
    const data = await res.json()
    expect(data.form).toEqual({ foo: 'bar' })
  })
})

[codecov]

Codecov Report

All modified and coverable lines are covered by tests ✅

Project coverage is 91.31%. Comparing base (15a83b1) to head (e9fe5ae).

Additional details and impacted files

@@           Coverage Diff           @@
##             main    #4109   +/-   ##
=======================================
  Coverage   91.30%   91.31%           
=======================================
  Files         168      168           
  Lines       10780    10787    +7     
  Branches     3085     3095   +10     
=======================================
+ Hits         9843     9850    +7     
  Misses        936      936           
  Partials        1        1           

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[EdamAme-x]

The problem here is that in c.req.valid, if you use form and json validators at the same time, you will get type inconsistency. (This has been a problem for some time.)
Types magic can solve this problem.