Add supported / unsupported version for fork enum (#16030)

* gate unreleased forks

* Preston + Bastin's feedback

* Rename back to all versions

* Clean up, mark PR ready for review

* Changelog

changelog/terence_guard-unreleased-forks.md

@@ -0,0 +1,3 @@
+### Added
+
+- Add supported version for fork versions

runtime/version/BUILD.bazel

@@ -25,6 +25,11 @@ go_library(
 go_test(
     name = "go_default_test",
     srcs = ["fork_test.go"],
-    embed = [":go_default_library"],
-    deps = ["@com_github_stretchr_testify//assert:go_default_library"],
+    deps = [
+        ":go_default_library",
+        "//config/params:go_default_library",
+        "//consensus-types/primitives:go_default_library",
+        "@com_github_stretchr_testify//assert:go_default_library",
+        "@com_github_stretchr_testify//require:go_default_library",
+    ],
 )

runtime/version/fork.go

@@ -25,11 +25,19 @@ var versionToString = map[int]string{
 	Deneb:     "deneb",
 	Electra:   "electra",
 	Fulu:      "fulu",
+	Gloas:     "gloas",
 }
 
 // stringToVersion and allVersions are populated in init()
 var stringToVersion = map[string]int{}
 var allVersions []int
+var supportedVersions []int
+
+// unsupportedVersions contains fork versions that exist in the enums but are not yet
+// enabled on any supported network. These versions are removed from All().
+var unsupportedVersions = map[int]struct{}{
+	Gloas: {},
+}
 
 // ErrUnrecognizedVersionName means a string does not match the list of canonical version names.
 var ErrUnrecognizedVersionName = errors.New("version name doesn't map to a known value in the enum")
@@ -53,9 +61,15 @@ func String(version int) string {
 	return name
 }
 
-// All returns a list of all known fork versions.
+// All returns a list of all supported fork versions.
 func All() []int {
-	return allVersions
+	return supportedVersions
+}
+
+// IsUnsupported reports whether the provided version is currently gate-kept.
+func IsUnsupported(version int) bool {
+	_, ok := unsupportedVersions[version]
+	return ok
 }
 
 func init() {
@@ -67,4 +81,12 @@ func init() {
 		i++
 	}
 	sort.Ints(allVersions)
+
+	supportedVersions = make([]int, 0, len(allVersions))
+	for _, v := range allVersions {
+		if _, skip := unsupportedVersions[v]; skip {
+			continue
+		}
+		supportedVersions = append(supportedVersions, v)
+	}
 }

runtime/version/fork_test.go

@@ -1,11 +1,15 @@
-package version
+package version_test
 
 import (
 	"slices"
 	"sort"
 	"testing"
 
+	"github.com/OffchainLabs/prysm/v7/config/params"
+	"github.com/OffchainLabs/prysm/v7/consensus-types/primitives"
+	"github.com/OffchainLabs/prysm/v7/runtime/version"
 	"github.com/stretchr/testify/assert"
+	"github.com/stretchr/testify/require"
 )
 
 func TestVersionString(t *testing.T) {
@@ -16,18 +20,18 @@ func TestVersionString(t *testing.T) {
 	}{
 		{
 			name:    "phase0",
-			version: Phase0,
+			version: version.Phase0,
 			want:    "phase0",
 		},
 		{
 			name:    "altair",
-			version: Altair,
+			version: version.Altair,
 			want:    "altair",
 		},
 	}
 	for _, tt := range tests {
 		t.Run(tt.name, func(t *testing.T) {
-			if got := String(tt.version); got != tt.want {
+			if got := version.String(tt.version); got != tt.want {
 				t.Errorf("String() = %v, want %v", got, tt.want)
 			}
 		})
@@ -35,7 +39,7 @@ func TestVersionString(t *testing.T) {
 }
 
 func TestVersionSorting(t *testing.T) {
-	versions := All()
+	versions := version.All()
 	expected := slices.Clone(versions)
 	sort.Ints(expected)
 	tests := []struct {
@@ -54,3 +58,74 @@ func TestVersionSorting(t *testing.T) {
 		})
 	}
 }
+
+func TestUnsupportedVersionsExcludedFromAll(t *testing.T) {
+	for _, v := range unsupportedVersions() {
+		assert.NotContains(t, version.All(), v, "unsupported version %s should not be returned by version.All()", version.String(v))
+	}
+}
+
+func TestUnsupportedVersionsAreNotScheduledOnTestnets(t *testing.T) {
+	unsupported := unsupportedVersions()
+	if len(unsupported) == 0 {
+		t.Skip("no unsupported versions defined")
+	}
+
+	testnetConfigs := []*params.BeaconChainConfig{
+		params.HoleskyConfig(),
+		params.SepoliaConfig(),
+		params.HoodiConfig(),
+	}
+
+	for _, v := range unsupported {
+		for _, cfg := range testnetConfigs {
+			epoch := forkEpochForVersion(cfg, v)
+			require.Equalf(
+				t,
+				cfg.FarFutureEpoch,
+				epoch,
+				"unsupported version %s should not be scheduled on %s (epoch=%d)",
+				version.String(v),
+				cfg.ConfigName,
+				epoch,
+			)
+		}
+	}
+}
+
+func forkEpochForVersion(cfg *params.BeaconChainConfig, v int) primitives.Epoch {
+	switch v {
+	case version.Phase0:
+		return cfg.GenesisEpoch
+	case version.Altair:
+		return cfg.AltairForkEpoch
+	case version.Bellatrix:
+		return cfg.BellatrixForkEpoch
+	case version.Capella:
+		return cfg.CapellaForkEpoch
+	case version.Deneb:
+		return cfg.DenebForkEpoch
+	case version.Electra:
+		return cfg.ElectraForkEpoch
+	case version.Fulu:
+		return cfg.FuluForkEpoch
+	default:
+		if version.IsUnsupported(v) {
+			return cfg.FarFutureEpoch
+		}
+		panic("forkEpochForVersion missing version " + version.String(v))
+	}
+}
+
+func unsupportedVersions() []int {
+	var unsupportedVersions []int
+	for v := 0; ; v++ {
+		if version.String(v) == "unknown version" {
+			break
+		}
+		if version.IsUnsupported(v) {
+			unsupportedVersions = append(unsupportedVersions, v)
+		}
+	}
+	return unsupportedVersions
+}