fix(snapshot): fail test when snapshot assertion is used with test.fails

[hi-ogawa]

Description

• Closes Dont update snapshot inside it.fails #9495

expect.soft handling is a bit annoying 🤔 I ended up with using error.__vitest_test_syntax_error__ to allow communicate between expect/runner/vitest packages basically.

This is likely a breaking change since users can do really weird thing with snapshot.

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[sheremet-va]

This is likely a breaking change since users can do really weird thing with snapshot.

I'm not so sure it's a breaking change. What kind of use cases does this break?

[hi-ogawa]

This is likely a breaking change since users can do really weird thing with snapshot.

I'm not so sure it's a breaking change. What kind of use cases does this break?

I removed one test from test/core/test/snapshot.test.ts and that's the one.

[sheremet-va]

This is likely a breaking change since users can do really weird thing with snapshot.

I'm not so sure it's a breaking change. What kind of use cases does this break?

I removed one test from test/core/test/snapshot.test.ts and that's the one.

Oh, I don't think this PR fixes the issue then. I thinktoMatchSnapshot should still work, it just shouldn't update the snapshot

[hi-ogawa]

This is likely a breaking change since users can do really weird thing with snapshot.

I'm not so sure it's a breaking change. What kind of use cases does this break?

I removed one test from test/core/test/snapshot.test.ts and that's the one.

Oh, I don't think this PR fixes the issue then. I thinktoMatchSnapshot should still work, it just shouldn't update the snapshot

test.fails outright rejecting snapshot matchers makes sense to me. This is basically same as how we reject expect(...).not.toMatchSnapshot(). Also that's at least what TestSyntaxError should entail. It shouldn't dependent on runtime surrounding.

[sheremet-va]

test.fails outright rejecting snapshot matchers makes sense to me.

Why? The test can have other assertions that fail, and snapshot to pass:

test.fails('test', () => {
  expect(shape).toMatchInlineSnapshot(`{ name: 'Alice' }`)
  expect(otherShape).toEqual({ name: 'Bob' }) // fails! 
})

It should just ignore the snapshot error when vitest tries to update it - at least that's what the issue is.

test.fails('test', () => {
  expect(shape).toMatchInlineSnapshot(`{ name: 'Bob' }`) // fails
})
vitest run -u // should ignore the error in `test.fails`, treat as --update=none in that test

[hi-ogawa]

The reason to prefer reject everything is because supporting the case by case can be confusing when users end up reaching such invalid state during the development without directly modifying the test itself to introduce forbidden combination of test.fails + snapshot.