Type Alias ExpectFunction<SyncAssertion>

ExpectFunction: (
    value: { "[InvalidAssertionChain]": "Only exists for autocompletion" },
    phrase: LiteralStringUnion<LeadingPhraseSuggestions<SyncAssertion>>,
    ...rest: LiteralStringUnion<PhraseSuggestions<SyncAssertion>>[],
) => void & <const Args extends unknown[]>(
    value: AssertValidChain<Args, SyncAssertion>,
    ...rest: Args,
) => void

The function part of Expect.

This is an intersection of all function signatures derived from the available synchronous assertions.

This function is typed in two different forms:

The first is the "real" type. All but the first args are collected, and asserts that it matches a real possible phrase. If no phrase matches, the first type becomes an impossible type (object with internal symbol, and text description)
The second is a hack. The first value is always "impossible". However that doesn't stop typescript from attempting a match, and providing auto-complete support, based on all the possible phrases from available assertions. The first phrase argument is narrowed to LeadingPhraseSuggestions so that interior connectors like 'and' and 'satisfying' are not suggested where a chain can only begin; subsequent arguments fall back to the full PhraseSuggestions set. Note that the autocompletion still does not respect "valid" phrases.