Unclear what matchers are compatible with the PactV3 interface

[mefellows]

The Pact V3 interface allows you to update the specification that you serialise to different versions, but it's unclear what Matchers should be used in that case.

i.e. it's possible to do:

const provider = new PactV3({
  consumer: 'consumer',
  provider: 'provider',
  spec: SpecificationVersion.SPECIFICATION_VERSION_V2
});

along side:

import { fromProviderState } from '@pact-foundation/pact/src/v3/matchers';

fromProviderState is not a valid matcher for the V2 specification as it's a V3 only matcher.

It should be clear and obvious what matchers can be used on the interface, and ideally constrained by types.

See this slack thread for context.

[YOU54F]

ahhh, I can see why this is causing confusion even more so, when reading this

pact-foundation/pact-ruby#276

Does the PactV3 interface, with the spec version v2, generate a v2 compliant spec, or just set the version to 2.0.0 in the spec. I assumed the PactV3 interface would generate v3 (or possibly) v4 pact specs in the future.

Fair bit of cognitive load required on the users part.