Implement message formatter

[aslakhellesoy]

The Cucumber JSON format is deprecated in Cucumber-Ruby, Cucumber-JVM and Cucumber-js. The recommended replacement is cucumber-messages.

It would be great to implement support for this in godog, and deprecate the cucumber formatter (The other Cucumber implementations call it the json formatter).

[aslakhellesoy]

Related issues: #338 #124 #205

[Johnlon]

@aslakhellesoy (and @dumpsterfireproject ) - I see this ticket is still open - confusingly I can also see that there is a formatter "events" in the code base and I'd assumed initially that the "event" format was the same as the "message" format defined in messages.go and formatted in the jdjson style of cucumer jvm.

BUT the "events" formatter doesn't conform at all to the cucumber/messages definitions in messages.go.

For example

• there is an event StepDefinitionFound that seems entirely a godog invention.
• TestStepStarted that is a defined event but godog emits different fields event/location/tiemstamp where as the messages.go definition has a bunch of other fields like TestCaseStartedId and TestStepId.

And the events in the generated file when using the "events" formatter aren't the ndjson style I was expecting but something else.

It's perhaps significant that the godog code doesn't acrually refer to the types in messages.go other than by string name, never by type.

Is the "event" formatter essentially unrelated to the "message" format?

Putting in the infra to make "message" work seems to touch much of the guts of godog - is that I wonder why this ticket is still open?

Thanks

(BTW long time no chat - came across some old google groups chats between us from back in 2010)

[Johnlon]

Likeky related to #617 as support for messages include support for attachments