Changes:

    Simplify nested complexity
    If an if blocks ends with a return statement then remove the else nesting.

Most of the changes has also been reported in golint https://goreportcard.com/report/github.com/ethereum/go-ethereum#golint

* cmd/devp2p/internal/ethtest: added large announcement tests

* cmd/devp2p/internal/ethtest: added large announcement tests

* cmd/devp2p/internal/ethtest: refactored stuff a bit

* cmd/devp2p/internal/ethtest: added TestMaliciousStatus/Handshake

* cmd/devp2p/internal/ethtest: fixed rebasing issue

* happy linter, happy life

* cmd/devp2p/internal/ethtest: used readAndServe

* stuff

* cmd/devp2p/internal/ethtest: fixed test cases

Resolves #21532

Co-authored-by: roger <dengjun@huobi.com>

* trie: fix tests to work on 32-bit systems

* les: make test work on 32-bit platform

* cmd/geth: fix windows-issues on tests

* trie: improve balance

* cmd/geth: make account tests less verbose + less mem intense

* rpc: make debug-level log output less verbose

* cmd/geth: lint

* cmd, core, eth, light, trie: disable recording preimage by default

* core, eth: fix unit tests

* core: fix import

* all: change to nopreimage

* cmd, core, eth, trie: use cache.preimages flag

* cmd: enable preimages for archive node

* cmd/utils, trie: simplify preimage tracking a bit

* core: fix linter

Co-authored-by: Péter Szilágyi <peterke@gmail.com>

* all: core: split vm.Config into BlockConfig and TxConfig

* core: core/vm: reset EVM between tx in block instead of creating new

* core/vm: added docs

This PR replaces the old test genesis.json and chain.rlp files in the testdata
directory for the eth protocol test suite, and also adds documentation for
running the eth test suite locally.

It also improves the test output text and adds more timeouts.

Co-authored-by: Felix Lange <fjl@twurst.com>

TAP is a text format for test results. Parsers for it are available in many languages,
making it easy to consume. I want TAP output from our protocol tests because the
Hive wrapper around them needs to know about the test names and their individual
results and logs. It would also be possible to just write this info as JSON, but I don't
want to invent a new format.

This also improves the normal console output for tests (when running without --tap).
It now prints -- RUN lines before any output from the test, and indents the log output
by one space.

The old one was wrong in two ways: the first block in chain.rlp was the
genesis block, and the genesis difficulty was below minimum difficulty.

This also contains some other fixes to the test.

* core/vm, core/state: implement EIP-2929 + YOLOv2

* core/state, core/vm: fix some review concerns

* core/state, core/vm: address review concerns

* core/vm: address review concerns

* core/vm: better documentation

* core/vm: unify sload cost as fully dynamic

* core/vm: fix typo

* core/vm/runtime: fix compilation flaw

* core/vm/runtime: fix renaming-err leftovers

* core/vm: renaming

* params/config: use correct yolov2 chainid for config

* core, params: use a proper new genesis for yolov2

* core/state/tests: golinter nitpicks

* add interrupt counter

* remove interrupt counter, allow ctrl-C to clear ONLY, ctrl-D will terminate console, stop node

* format

* add instructions to exit

* fix tests

This change implements the Discovery v5.1 wire protocol and
also adds an interactive test suite for this protocol.

This fixes issues with the protocol handshake and status exchange
and adds support for responding to GetBlockHeaders requests.

* accounts, signer: implement gnosis safe support

* common/math: add type for marshalling big to dec

* accounts, signer: properly sign gnosis requests

* signer, clef: implement account_signGnosisTx

* signer: fix auditlog print, change rpc-name (signGnosisTx to signGnosisSafeTx)

* signer: pass validation-messages/warnings to the UI for gnonsis-safe txs

* signer/core: minor change to validationmessages of typed data

This change adds a test framework for the "eth" protocol and some basic
tests. The tests can be run using the './devp2p rlpx eth-test' command.

This change moves the RLPx protocol implementation into a separate package,
p2p/rlpx. The new package can be used to establish RLPx connections for
protocol testing purposes.

Co-authored-by: Felix Lange <fjl@twurst.com>

* cmd/utils: use preconfigured testnet flags instead of networkid

* cmd/utils: shorter description

Co-authored-by: Martin Holst Swende <martin@swende.se>

* Update flags.go

Co-authored-by: Martin Holst Swende <martin@swende.se>

* les, les/lespay/server: refactor client pool

* les: use ns.Operation and sub calls where needed

* les: fixed tests

* les: removed active/inactive logic from peerSet

* les: removed active/inactive peer logic

* les: fixed linter warnings

* les: fixed more linter errors and added missing metrics

* les: addressed comments

* cmd/geth: fixed TestPriorityClient

* les: simplified clientPool state machine

* les/lespay/server: do not use goroutine for balance callbacks

* internal/web3ext: fix addBalance required parameters

* les: removed freeCapacity, always connect at minCapacity initially

* les: only allow capacity change with priority status

Co-authored-by: rjl493456442 <garyrong0905@gmail.com>

* cmd/geth: print warning when whisper config is present in toml

* Update cmd/geth/config.go

Co-authored-by: Martin Holst Swende <martin@swende.se>

* cmd, eth: offer maxprice flag for overwritting price cap

* eth: rename default price cap

* whisper: remove whisper

* Update cmd/geth/config.go

Co-authored-by: Marius van der Wijden <m.vanderwijden@live.de>

* cmd/geth: warn on enabling whisper + remove more whisper deps

* mobile: remove all whisper references

Co-authored-by: Marius van der Wijden <m.vanderwijden@live.de>
Co-authored-by: Martin Holst Swende <martin@swende.se>

* t8ntool: add output basedir

* t8ntool: add txhash to trace filename

* t8ntool: don't default to '.' basedir, allow absolute paths

* cmd/geth/tests: try to fix spurious travis failure in les tests

* cmd/geth: les_test - remove extraneous option during boot

* cmd/utils: grant snapshot cache to trie if disabled

* eth: fix up default non-mainnet cache distribution