feat(beacon-node): run consensus-specs fork-choice compliance tests

packages/beacon-node/package.json

@@ -100,6 +100,8 @@
     "test:sim": "vitest run test/sim/**/*.test.ts",
     "test:sim:blobs": "vitest run test/sim/4844-interop.test.ts",
     "download-spec-tests": "node --loader=ts-node/esm test/spec/downloadTests.ts",
+    "download-compliance-fc-tests": "../../scripts/download-compliance-fc-tests.sh",
+    "test:spec:compliance-fc": "../../scripts/compliance-fc-report.sh",
     "test:spec:bls": "vitest run --project spec-minimal test/spec/bls/",
     "test:spec:general": "vitest run --project spec-minimal test/spec/general/",
     "test:spec:minimal": "vitest run --project spec-minimal test/spec/presets/",

packages/beacon-node/test/spec/presets/compliance_fork_choice.test.ts

@@ -0,0 +1,60 @@
+import fs from "node:fs";
+import path from "node:path";
+import {describe, it} from "vitest";
+import {ACTIVE_PRESET} from "@lodestar/params";
+import {complianceForkChoiceSpecTests} from "../specTestVersioning.js";
+import {forkChoiceTest} from "../utils/forkChoiceRunner.js";
+import {specTestIterator} from "../utils/specTestIterator.js";
+import {RunnerType} from "../utils/types.js";
+
+// Compliance fork choice tests share the standard spec-test layout under each
+// config archive (verified against the `small.tar.gz` artifact from the
+// consensus-specs "Compliance Tests" workflow):
+//
+//   spec-tests-compliance/<config>/tests/<preset>/<fork>/fork_choice_compliance/<handler>/<suite>/<case>/
+//
+// We reuse `specTestIterator` and register a runner under the name
+// `fork_choice_compliance` (consensus-specs naming, not Prysm's
+// `compliance_fork_choice`). Each config gets a `compliance_fork_choice/<config>/`
+// prefix on its test IDs so reports can differentiate when multiple configs
+// are extracted side-by-side.
+
+for (const configName of complianceForkChoiceSpecTests.configs) {
+  const configRoot = path.join(complianceForkChoiceSpecTests.outputDir, configName);
+
+  if (!fs.existsSync(configRoot)) {
+    describe(`compliance_fork_choice/${configName}`, () => {
+      it.skip(
+        `compliance test data not present at ${configRoot}; ` +
+          `run \`./scripts/download-compliance-fc-tests.sh --config ${configName}\` to fetch`,
+        () => {}
+      );
+    });
+    continue;
+  }
+
+  // The published artifact extracts to `<config>/tests/<preset>/...` but allow a
+  // flatter `<config>/<preset>/...` layout in case future tarballs drop the prefix.
+  const presetRoot = [path.join(configRoot, "tests", ACTIVE_PRESET), path.join(configRoot, ACTIVE_PRESET)].find((p) =>
+    fs.existsSync(p)
+  );
+
+  if (presetRoot === undefined) {
+    describe(`compliance_fork_choice/${configName}/${ACTIVE_PRESET}`, () => {
+      it.skip(`compliance ${configName} archive does not contain preset ${ACTIVE_PRESET}`, () => {});
+    });
+    continue;
+  }
+
+  specTestIterator(
+    presetRoot,
+    {
+      fork_choice_compliance: {
+        type: RunnerType.default,
+        fn: forkChoiceTest({onlyPredefinedResponses: false}),
+      },
+    },
+    undefined,
+    `compliance_fork_choice/${configName}/`
+  );
+}