Printf formatting not working as expected - possible bug?

Describe the bug

The printf formatting isn’t working as expected from the example in the documentation.

describe.each([
  { a: 1, b: 1, expected: 2 },
  { a: 1, b: 2, expected: 3 },
  { a: 2, b: 1, expected: 3 },
])('describe object add(%i, %i)', ({ a, b, expected }) => {
  test(`returns ${expected}`, () => {
    expect(a + b).toBe(expected)
  })
})

I would expect to get

describe object add(1, 1)
    returns 2
describe object add(1, 2)
    returns 3
describe object add(2, 1)
    returns 3

Reproduction

Run the example code.

You will get output:

System Info

Node: v16.5.0
Vite: 2.9.1
Vitest: 0.9.3

Used Package Manager

pnpm

Validations

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• Read the Contributing Guidelines.
• Read the docs.
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• The provided reproduction is a minimal reproducible example of the bug.

[QuiiBz]

@ooohmydawn the documentation has been updated with a working example in https://github.com/vitest-dev/vitest/pull/1368

The right syntax is add($a, $b) instead of add(%i, %i), see https://vitest.dev/api/#describe-each

[btea]

This does not seem to handle complex data formats: https://github.com/vitest-dev/vitest/blob/f8db7d7346c3ff3650bf450f5eba93b0dd8e73ff/packages/vitest/src/runtime/suite.ts#L28-L31