Update Prater config to include Altair fork epoch (#9467)

* Update Prater config after https://github.com/eth2-clients/eth2-networks/pull/58. Add tests to enforce compliance.

* gofmt

* spec: true

* fix test

Co-authored-by: prylabs-bulldozer[bot] <58059840+prylabs-bulldozer[bot]@users.noreply.github.com>

WORKSPACE

@@ -263,6 +263,22 @@ filegroup(
     url = "https://github.com/ethereum/consensus-specs/archive/refs/tags/%s.tar.gz" % consensus_spec_version,
 )
 
+http_archive(
+    name = "eth2_networks",
+    build_file_content = """
+filegroup(
+    name = "configs",
+    srcs = glob([
+        "shared/**/config.yaml",
+    ]),
+    visibility = ["//visibility:public"],
+)
+    """,
+    sha256 = "9dc47bf6b14aed7fac8833e35ab83a69131b43fa5789b3256bf1ac3d4861aeb8",
+    strip_prefix = "eth2-networks-7fa1b868985ee24aad65567f9250cf7fa86f97b1",
+    url = "https://github.com/eth2-clients/eth2-networks/archive/7fa1b868985ee24aad65567f9250cf7fa86f97b1.tar.gz",
+)
+
 http_archive(
     name = "com_github_bazelbuild_buildtools",
     sha256 = "7a182df18df1debabd9e36ae07c8edfa1378b8424a04561b674d933b965372b3",

beacon-chain/rpc/eth/beacon/config_test.go

@@ -124,7 +124,7 @@ func TestGetSpec(t *testing.T) {
 	resp, err := server.GetSpec(context.Background(), &emptypb.Empty{})
 	require.NoError(t, err)
 
-	assert.Equal(t, 89, len(resp.Data))
+	assert.Equal(t, 90, len(resp.Data))
 	for k, v := range resp.Data {
 		switch k {
 		case "CONFIG_NAME":
@@ -313,6 +313,8 @@ func TestGetSpec(t *testing.T) {
 			assert.Equal(t, "0x08000000", v)
 		case "DOMAIN_CONTRIBUTION_AND_PROOF":
 			assert.Equal(t, "0x09000000", v)
+		case "TRANSITION_TOTAL_DIFFICULTY":
+			assert.Equal(t, "0", v)
 		default:
 			t.Errorf("Incorrect key: %s", k)
 		}

shared/params/BUILD.bazel

@@ -37,11 +37,14 @@ go_test(
         "checktags_test.go",
         "config_test.go",
         "loader_test.go",
+        "testnet_config_test.go",
+        "testnet_prater_config_test.go",
     ],
     data = glob(["*.yaml"]) + [
         "@consensus_spec//:spec_data",
         "@consensus_spec_tests_mainnet//:test_data",
         "@consensus_spec_tests_minimal//:test_data",
+        "@eth2_networks//:configs",
     ],
     embed = [":go_default_library"],
     gotags = ["develop"],

shared/params/config.go

@@ -138,6 +138,7 @@ type BeaconChainConfig struct {
 	ShardingForkEpoch           types.Epoch             `yaml:"SHARDING_FORK_EPOCH" spec:"true"`   // ShardingForkEpoch is used to represent the assigned fork epoch for sharding.
 	ForkVersionSchedule         map[[4]byte]types.Epoch // Schedule of fork epochs by version.
 	MinAnchorPowBlockDifficulty uint64                  `yaml:"MIN_ANCHOR_POW_BLOCK_DIFFICULTY" spec:"true"` // MinAnchorPowBlockDifficulty specifies the target chain difficulty at the time of the merge.
+	TransitionTotalDifficulty   uint64                  `yaml:"TRANSITION_TOTAL_DIFFICULTY" spec:"true"`     // TransitionTotalDifficulty is part of the experimental merge spec. This value is not used (yet) and is expected to be a uint256.
 
 	// Weak subjectivity values.
 	SafetyDecay uint64 // SafetyDecay is defined as the loss in the 1/3 consensus safety margin of the casper FFG mechanism.

shared/params/loader_test.go

@@ -100,28 +100,7 @@ func TestLoadConfigFileMainnet(t *testing.T) {
 		assert.Equal(t, c1.DomainSelectionProof, c2.DomainSelectionProof, "%s: DomainSelectionProof", name)
 		assert.Equal(t, c1.DomainAggregateAndProof, c2.DomainAggregateAndProof, "%s: DomainAggregateAndProof", name)
 
-		// Ensure all fields from the yaml file exist, were set, and correctly match the expected value.
-		ft1 := reflect.TypeOf(*c1)
-		for _, field := range fields {
-			var found bool
-			for i := 0; i < ft1.NumField(); i++ {
-				v, ok := ft1.Field(i).Tag.Lookup("yaml")
-				if ok && v == field {
-					found = true
-					v1 := reflect.ValueOf(*c1).Field(i).Interface()
-					v2 := reflect.ValueOf(*c2).Field(i).Interface()
-					if reflect.ValueOf(v1).Kind() == reflect.Slice {
-						assert.DeepEqual(t, v1, v2, "%s: %s", name, field)
-					} else {
-						assert.Equal(t, v1, v2, "%s: %s", name, field)
-					}
-					break
-				}
-			}
-			if !found {
-				t.Errorf("No struct tag found `yaml:%s`", field)
-			}
-		}
+		assertYamlFieldsMatch(t, name, fields, c1, c2)
 	}
 
 	t.Run("mainnet", func(t *testing.T) {
@@ -263,3 +242,28 @@ func fieldsFromYaml(t *testing.T, fp string) []string {
 
 	return keys
 }
+
+func assertYamlFieldsMatch(t *testing.T, name string, fields []string, c1, c2 *BeaconChainConfig) {
+	// Ensure all fields from the yaml file exist, were set, and correctly match the expected value.
+	ft1 := reflect.TypeOf(*c1)
+	for _, field := range fields {
+		var found bool
+		for i := 0; i < ft1.NumField(); i++ {
+			v, ok := ft1.Field(i).Tag.Lookup("yaml")
+			if ok && v == field {
+				found = true
+				v1 := reflect.ValueOf(*c1).Field(i).Interface()
+				v2 := reflect.ValueOf(*c2).Field(i).Interface()
+				if reflect.ValueOf(v1).Kind() == reflect.Slice {
+					assert.DeepEqual(t, v1, v2, "%s: %s", name, field)
+				} else {
+					assert.Equal(t, v1, v2, "%s: %s", name, field)
+				}
+				break
+			}
+		}
+		if !found {
+			t.Errorf("No struct tag found `yaml:%s`", field)
+		}
+	}
+}

shared/params/testnet_config_test.go

@@ -0,0 +1,16 @@
+package params
+
+import (
+	"path"
+	"testing"
+
+	"github.com/bazelbuild/rules_go/go/tools/bazel"
+	"github.com/prysmaticlabs/prysm/shared/testutil/require"
+)
+
+func testnetConfigFilePath(t *testing.T, network string) string {
+	filepath, err := bazel.Runfile("external/eth2_networks")
+	require.NoError(t, err)
+	configFilePath := path.Join(filepath, "shared", network, "config.yaml")
+	return configFilePath
+}

shared/params/testnet_prater_config.go

@@ -39,6 +39,11 @@ func PraterConfig() *BeaconChainConfig {
 	cfg.SecondsPerETH1Block = 14
 	cfg.DepositChainID = eth1Params.GoerliChainConfig.ChainID.Uint64()
 	cfg.DepositNetworkID = eth1Params.GoerliChainConfig.ChainID.Uint64()
-	cfg.DepositContractAddress = "0xff50ed3d0ec03ac01d4c79aad74928bff48a7b2b"
+	cfg.AltairForkEpoch = 36660
+	cfg.AltairForkVersion = []byte{0x1, 0x0, 0x10, 0x20}
+	cfg.ShardingForkVersion = []byte{0x3, 0x0, 0x10, 0x20}
+	cfg.MergeForkVersion = []byte{0x2, 0x0, 0x10, 0x20}
+	cfg.TransitionTotalDifficulty = 4294967296
+	cfg.DepositContractAddress = "0xff50ed3d0ec03aC01D4C79aAd74928BFF48a7b2b"
 	return cfg
 }

shared/params/testnet_prater_config_test.go

@@ -0,0 +1,12 @@
+package params
+
+import (
+	"testing"
+)
+
+func TestPraterConfigMatchesUpstreamYaml(t *testing.T) {
+	configFP := testnetConfigFilePath(t, "prater")
+	LoadChainConfigFile(configFP)
+	fields := fieldsFromYaml(t, configFP)
+	assertYamlFieldsMatch(t, "prater", fields, BeaconConfig(), PraterConfig())
+}