* get conclude signal working properly; don't allocate a vector

* wip: add test suite / example / explanation for using utility subsystem

Unfortunately, the test fails right now for reasons which seem
very odd. Just have to keep poking at it.

* explicitly import everything

* fix subsystem-util test

The root problem here was two-fold:

- there was a circular dependency from subsystem -> test-helpers/subsystem ->
  subsystem
- cfg(test) doesn't propagate between crates

The solution: move the subsystem test helpers into a sub-module
within subsystem. Publicly export them from the previous location
so no other code breaks.

Doing this has an additional benefit: it ensures that no production
code can ever accidentally use the subsystem helpers, as they are compile-
gated on cfg(test).

* fully commit to moving test helpers into a subsystem module

* add some more tests

* get rid of log tests in favor of real error forwarding

It's not obvious whether we'll ever really want to chase down
these errors outside a testing context, but having the capability
won't hurt.

* fix issue which caused test to hang on osx

* only require that job errors are PartialEq when testing

also fix polkadot-node-core-backing tests

* get rid of any notion of partialeq

* rethink testing

Combine tests of starting and stopping job: leaving a test executor
with a job running was pretty clearly the cause of the sometimes-hang.

Also, add a timeout so tests _can't_ hang anymore; they just fail
after a while.

* rename fwd_errors -> forward_errors

* warn on error propagation failure

* fix unused import leftover from merge

* derive eq for subsystemerror

* create a README on Runtime APIs

* add ParaId type

* write up runtime APIs

* more preamble

* rename

* rejig runtime APIs

* add occupied_since to `BlockNumber`

* skeleton crate for runtime API subsystem

* improve group_for_core

* improve docs on availability cores runtime API

* guide: freed -> free

* add primitives for runtime APIs

* create a v1 ParachainHost API trait

* guide: make validation code return `Option`al.

* skeleton runtime API helpers

* make parachain-host runtime-generic

* skeleton for most runtime API implementation functions

* guide: add runtime API helper methods

* implement new helpers of the inclusion module

* guide: remove retries check, as it is unneeded

* implement helpers for scheduler module for Runtime APIs

* clean up `validator_groups` implementation

* implement next_rotation_at and last_rotation_at

* guide: more helpers on GroupRotationInfo

* almost finish implementing runtime APIs

* add explicit block parameter to runtime API fns

* guide: generalize number parameter

* guide: add group_responsible to occupied-core

* update primitives due to guide changes

* finishing touches on runtime API implementation; squash warnings

* break out runtime API impl to separate file

* add tests for next_up logic

* test group rotation info

* point to filed TODO

* remove unused TODO [now]

* indentation

* guide: para -> para_id

* rename para field to para_id for core meta

* remove reference to outdated AvailabilityCores type

* add an event in `inclusion` for candidates being included or timing out

* guide: candidate events

* guide: adjust language

* Candidate events type from guide and adjust inclusion event

* implement `candidate_events` runtime API

* fix runtime test compilation

* max -> min

* fix typos

* guide: add `RuntimeAPIRequest::CandidateEvents`

* Use SpawnNamed instead of Spawn in Overseer

* reexport SpawnNamed and fix doc tests

* Fix deps

* create a v1 primitives module

* Improve guide on availability types

* punctuate

* new parachains runtime uses new primitives

* tests of new runtime now use new primitives

* add ErasureChunk to guide

* export erasure chunk from v1 primitives

* subsystem crate uses v1 primitives

* node-primitives uses new v1 primitives

* port overseer to new primitives

* new-proposer uses v1 primitives (no ParachainHost anymore)

* fix no-std compilation for primitives

* service-new uses v1 primitives

* network-bridge uses new primitives

* statement distribution uses v1 primitives

* PoV distribution uses v1 primitives; add PoV::hash fn

* move parachain to v0

* remove inclusion_inherent module and place into v1

* remove everything from primitives crate root

* remove some unused old types from v0 primitives

* point everything else at primitives::v0

* squanch some warns up

* add RuntimeDebug import to no-std as well

* port over statement-table and validation

* fix final errors in validation and node-primitives

* add dummy Ord impl to committed candidate receipt

* guide: update CandidateValidationMessage

* add primitive for validationoutputs

* expand CandidateValidationMessage further

* bikeshed

* add some impls to omitted-validation-data and available-data

* expand CandidateValidationMessage

* make erasure-coding generic over v1/v0

* update usages of erasure-coding

* implement commitments.hash()

* use Arc<Pov> for CandidateValidation

* improve new erasure-coding method names

* fix up candidate backing

* update docs a bit

* fix most tests and add short-circuiting to make_pov_available

* fix remainder of candidate backing tests

* squanching warns

* squanch it up

* some fallout

* overseer fallout

* free from polkadot-test-service hell

* introduce candidatedescriptor type

* add PoVDistribution message type

* loosen bound on PoV Distribution to account for equivocations

* re-export some types from the messages module

* begin PoV Distribution subsystem

* remove redundant index from PoV distribution

* define state machine for pov distribution

* handle overseer signals

* set up control flow

* remove `ValidatorStatement` section

* implement PoV fetching

* implement distribution logic

* add missing `

* implement some network bridge event handlers

* stub for message processing, handle our view change

* control flow for handling messages

* handle `awaiting` message

* handle any incoming PoVs and redistribute

* actually provide a subsystem implementation

* remove set-builder notation

* begin testing PoV distribution

* test that we send awaiting messages only to peers with same view

* ensure we distribute awaited PoVs to peers on view changes

* test that peers can complete fetch and are rewarded

* test some reporting logic

* ensure peer is reported for flooding

* test punishing peers diverging from awaited protocol

* test that we eagerly complete peers' awaited PoVs based on what we receive

* test that we prune the awaited set after receiving

* expand pov-distribution in guide to match a change I made

* remove unneeded import

* set up data types and control flow for statement distribution

* add some set-like methods to View

* implement sending to peers

* start fixing equivocation handling

* Add a section to the statement distribution subsystem on equivocations and flood protection

* fix typo and amend wording

* implement flood protection

* have peer knowledge tracker follow when peer first learns about a candidate

* send dependents after circulating

* add another TODO

* trigger send in one more place

* refactors from review

* send new statements to candidate backing

* instantiate active head data with runtime API values

* track our view changes and peer view changes

* apply a benefit to peers who send us statements we want

* remove unneeded TODO

* add some comments and improve Hash implementation

* start tests and fix `note_statement`

* test active_head seconding logic

* test that the per-peer tracking logic works

* test per-peer knowledge tracker

* test that peer view updates lead to messages being sent

* test statement circulation

* address review comments

* have view set methods return references

* Subsystem::start takes self by-value

* fix doc-test compilation

* network bridge skeleton

* move some primitives around and add debug impls

* protocol registration glue & abstract network interface

* add send_msgs to subsystemctx

* select logic

* transform different events into actions and handle

* implement remaining network bridge state machine

* start test skeleton

* make network methods asynchronous

* extract subsystem out to subsystem crate

* port over overseer to subsystem context trait

* fix minimal example

* fix overseer doc test

* update network-bridge crate

* write a subsystem test-helpers crate

* write a network test helper for network-bridge

* set up (broken) view test

* Revamp network to be more async-friendly and not require Sync

* fix spacing

* fix test compilation

* insert side-channel for actions

* Add some more message types to AllMessages

* introduce a test harness

* add some tests

* ensure service compiles and passes tests

* fix typo

* fix service-new compilation

* Subsystem test helpers send messages synchronously

* remove smelly action inspector

* remove superfluous let binding

* fix warnings

* Update node/network/bridge/src/lib.rs

Co-authored-by: Peter Goodspeed-Niklaus <[email protected]>

* fix compilation

Co-authored-by: Peter Goodspeed-Niklaus <[email protected]>

* establish new `node` folder for overseer, messages, and subsystems

* extract message types from overseer crate

* remove doc links