refactor: Split config package so it doesn't import core, core/vm (#734)

Co-authored-by: Quentin McGaw <[email protected]>

Author: Darioush Jalali

plugin/evm/config.go

@@ -0,0 +1,21 @@
+// (c) 2025, Ava Labs, Inc. All rights reserved.
+// See the file LICENSE for licensing terms.
+
+package evm
+
+import (
+	"github.com/ava-labs/coreth/core/txpool/legacypool"
+	"github.com/ava-labs/coreth/plugin/evm/config"
+)
+
+// defaultTxPoolConfig uses [legacypool.DefaultConfig] to make a [config.TxPoolConfig]
+// that can be passed to [config.Config.SetDefaults].
+var defaultTxPoolConfig = config.TxPoolConfig{
+	PriceLimit:   legacypool.DefaultConfig.PriceLimit,
+	PriceBump:    legacypool.DefaultConfig.PriceBump,
+	AccountSlots: legacypool.DefaultConfig.AccountSlots,
+	GlobalSlots:  legacypool.DefaultConfig.GlobalSlots,
+	AccountQueue: legacypool.DefaultConfig.AccountQueue,
+	GlobalQueue:  legacypool.DefaultConfig.GlobalQueue,
+	Lifetime:     legacypool.DefaultConfig.Lifetime,
+}

plugin/evm/config/config.go

@@ -9,8 +9,6 @@ import (
 	"time"
 
 	"github.com/ava-labs/avalanchego/utils/constants"
-	"github.com/ava-labs/coreth/core/txpool/legacypool"
-	"github.com/ava-labs/coreth/eth"
 	"github.com/ethereum/go-ethereum/common"
 	"github.com/ethereum/go-ethereum/common/hexutil"
 	"github.com/spf13/cast"
@@ -224,28 +222,37 @@ type Config struct {
 	HttpBodyLimit uint64 `json:"http-body-limit"`
 }
 
+// TxPoolConfig contains the transaction pool config to be passed
+// to [Config.SetDefaults].
+type TxPoolConfig struct {
+	PriceLimit   uint64
+	PriceBump    uint64
+	AccountSlots uint64
+	GlobalSlots  uint64
+	AccountQueue uint64
+	GlobalQueue  uint64
+	Lifetime     time.Duration
+}
+
 // EthAPIs returns an array of strings representing the Eth APIs that should be enabled
 func (c Config) EthAPIs() []string {
 	return c.EnabledEthAPIs
 }
 
-func (c Config) EthBackendSettings() eth.Settings {
-	return eth.Settings{MaxBlocksPerRequest: c.MaxBlocksPerRequest}
-}
-
-func (c *Config) SetDefaults() {
+func (c *Config) SetDefaults(txPoolConfig TxPoolConfig) {
 	c.EnabledEthAPIs = defaultEnabledAPIs
 	c.RPCGasCap = defaultRpcGasCap
 	c.RPCTxFeeCap = defaultRpcTxFeeCap
 	c.MetricsExpensiveEnabled = defaultMetricsExpensiveEnabled
 
-	c.TxPoolPriceLimit = legacypool.DefaultConfig.PriceLimit
-	c.TxPoolPriceBump = legacypool.DefaultConfig.PriceBump
-	c.TxPoolAccountSlots = legacypool.DefaultConfig.AccountSlots
-	c.TxPoolGlobalSlots = legacypool.DefaultConfig.GlobalSlots
-	c.TxPoolAccountQueue = legacypool.DefaultConfig.AccountQueue
-	c.TxPoolGlobalQueue = legacypool.DefaultConfig.GlobalQueue
-	c.TxPoolLifetime.Duration = legacypool.DefaultConfig.Lifetime
+	// TxPool settings
+	c.TxPoolPriceLimit = txPoolConfig.PriceLimit
+	c.TxPoolPriceBump = txPoolConfig.PriceBump
+	c.TxPoolAccountSlots = txPoolConfig.AccountSlots
+	c.TxPoolGlobalSlots = txPoolConfig.GlobalSlots
+	c.TxPoolAccountQueue = txPoolConfig.AccountQueue
+	c.TxPoolGlobalQueue = txPoolConfig.GlobalQueue
+	c.TxPoolLifetime.Duration = txPoolConfig.Lifetime
 
 	c.APIMaxDuration.Duration = defaultApiMaxDuration
 	c.WSCPURefillRate.Duration = defaultWsCpuRefillRate

plugin/evm/imports_test.go

@@ -0,0 +1,72 @@
+// (c) 2025, Ava Labs, Inc. All rights reserved.
+// See the file LICENSE for licensing terms.
+
+package evm
+
+import (
+	"fmt"
+	"testing"
+
+	"github.com/stretchr/testify/require"
+	"golang.org/x/tools/go/packages"
+)
+
+// getDependencies takes a fully qualified package name and returns a map of all
+// its recursive package imports (including itself) in the same format.
+func getDependencies(packageName string) (map[string]struct{}, error) {
+	// Configure the load mode to include dependencies
+	cfg := &packages.Config{Mode: packages.NeedDeps | packages.NeedImports | packages.NeedName | packages.NeedModule}
+	pkgs, err := packages.Load(cfg, packageName)
+	if err != nil {
+		return nil, fmt.Errorf("failed to load package: %v", err)
+	}
+
+	if len(pkgs) == 0 || pkgs[0].Errors != nil {
+		return nil, fmt.Errorf("failed to load package %s", packageName)
+	}
+
+	deps := make(map[string]struct{})
+	var collectDeps func(pkg *packages.Package)
+	collectDeps = func(pkg *packages.Package) {
+		if _, ok := deps[pkg.PkgPath]; ok {
+			return // Avoid re-processing the same dependency
+		}
+		deps[pkg.PkgPath] = struct{}{}
+		for _, dep := range pkg.Imports {
+			collectDeps(dep)
+		}
+	}
+
+	// Start collecting dependencies
+	collectDeps(pkgs[0])
+	return deps, nil
+}
+
+func TestMustNotImport(t *testing.T) {
+	withRepo := func(pkg string) string {
+		const repo = "github.com/ava-labs/coreth"
+		return fmt.Sprintf("%s/%s", repo, pkg)
+	}
+	mustNotImport := map[string][]string{
+		// The following sub-packages of plugin/evm must not import core, core/vm
+		// so clients (e.g., wallets, e2e tests) can import them without pulling in
+		// the entire VM logic.
+		// Importing these packages configures libevm globally and it is not
+		// possible to do so for both coreth and subnet-evm, where the client may
+		// wish to connect to multiple chains.
+		"plugin/evm/atomic": {"core", "core/vm"},
+		"plugin/evm/client": {"core", "core/vm"},
+		"plugin/evm/config": {"core", "core/vm"},
+	}
+
+	for packageName, forbiddenImports := range mustNotImport {
+		imports, err := getDependencies(withRepo(packageName))
+		require.NoError(t, err)
+
+		for _, forbiddenImport := range forbiddenImports {
+			fullForbiddenImport := withRepo(forbiddenImport)
+			_, found := imports[fullForbiddenImport]
+			require.False(t, found, "package %s must not import %s, check output of go list -f '{{ .Deps }}' \"%s\" ", packageName, fullForbiddenImport, withRepo(packageName))
+		}
+	}
+}

plugin/evm/vm.go

@@ -339,7 +339,7 @@ func (vm *VM) Initialize(
 	fxs []*commonEng.Fx,
 	appSender commonEng.AppSender,
 ) error {
-	vm.config.SetDefaults()
+	vm.config.SetDefaults(defaultTxPoolConfig)
 	if len(configBytes) > 0 {
 		if err := json.Unmarshal(configBytes, &vm.config); err != nil {
 			return fmt.Errorf("failed to unmarshal config %s: %w", string(configBytes), err)
@@ -660,7 +660,7 @@ func (vm *VM) initializeChain(lastAcceptedHash common.Hash) error {
 		&vm.ethConfig,
 		&EthPushGossiper{vm: vm},
 		vm.chaindb,
-		vm.config.EthBackendSettings(),
+		eth.Settings{MaxBlocksPerRequest: vm.config.MaxBlocksPerRequest},
 		lastAcceptedHash,
 		dummy.NewFakerWithClock(callbacks, &vm.clock),
 		&vm.clock,

plugin/evm/vm_test.go

@@ -402,7 +402,7 @@ func TestVMConfigDefaults(t *testing.T) {
 	_, vm, _, _, _ := GenesisVM(t, false, "", configJSON, "")
 
 	var vmConfig config.Config
-	vmConfig.SetDefaults()
+	vmConfig.SetDefaults(defaultTxPoolConfig)
 	vmConfig.RPCTxFeeCap = txFeeCap
 	vmConfig.EnabledEthAPIs = enabledEthAPIs
 	require.Equal(t, vmConfig, vm.config, "VM Config should match default with overrides")
@@ -414,7 +414,7 @@ func TestVMNilConfig(t *testing.T) {
 
 	// VM Config should match defaults if no config is passed in
 	var vmConfig config.Config
-	vmConfig.SetDefaults()
+	vmConfig.SetDefaults(defaultTxPoolConfig)
 	require.Equal(t, vmConfig, vm.config, "VM Config should match default config")
 	require.NoError(t, vm.Shutdown(context.Background()))
 }