add test for reading era1

packages/era/package.json

@@ -42,8 +42,7 @@
     "lint": "npm run biome && eslint --config .eslintrc.cjs . --ext .js,.ts",
     "lint:fix": "npm run biome:fix && eslint --fix --config .eslintrc.cjs . --ext .js,.ts",
     "prepublishOnly": "../../config/cli/prepublish.sh",
-    "test": "npm run test:node && npm run test:browser",
-    "test:browser": "npx vitest run --config=../../config/vitest.config.browser.mts",
+    "test": "npm run test:node",
     "test:node": "npx vitest run",
     "tsc": "../../config/cli/ts-compile.sh"
   },

packages/era/test/era1.spec.ts

@@ -0,0 +1,63 @@
+import { createBlockHeaderFromBytesArray } from '@ethereumjs/block'
+import { bytesToHex } from '@ethereumjs/util'
+import { readFileSync } from 'fs'
+import { assert, describe, expect, it } from 'vitest'
+
+import {
+  Era1Types,
+  getBlockIndex,
+  parseBlockTuple,
+  readBlockIndex,
+  readBlockTupleAtOffset,
+  readOtherEntries,
+  validateERA1,
+} from '../src/index.js'
+
+// Reference file donwloaded from era1.ethportal.net
+const filePath = './test/mainnet-00000-5ec1ffb8.era1'
+const expectedLength = 3891337
+
+function readBinaryFile(filePath: string): Uint8Array {
+  const buffer = readFileSync(filePath)
+  return new Uint8Array(buffer)
+}
+
+describe('Read Era1', async () => {
+  const era1File = readBinaryFile(filePath)
+  it('should read the file', () => {
+    expect(era1File.length).toEqual(expectedLength)
+  })
+  const blockIndex = getBlockIndex(era1File)
+  it('should have block index type', () => {
+    assert.deepEqual(blockIndex.type, Era1Types.BlockIndex)
+  })
+  it('should have correct count', () => {
+    expect(blockIndex.count).toEqual(8192)
+  })
+  const { startingNumber, offsets } = readBlockIndex(blockIndex.data, blockIndex.count)
+  it('should read block index', () => {
+    expect(startingNumber).toEqual(0)
+    expect(offsets.length).toEqual(8192)
+  })
+  const { accumulatorRoot, otherEntries } = await readOtherEntries(era1File)
+  it('should read accumulator root', () => {
+    assert.equal(
+      bytesToHex(accumulatorRoot),
+      '0x5ec1ffb8c3b146f42606c74ced973dc16ec5a107c0345858c343fc94780b4218',
+    )
+  })
+  it('should read other entries', () => {
+    expect(otherEntries.length).toEqual(0)
+  })
+  it('should read first block tuple', async () => {
+    const tupleEntry = readBlockTupleAtOffset(era1File, blockIndex.recordStart, offsets[0])
+    const { header, totalDifficulty } = await parseBlockTuple(tupleEntry)
+    const blockHeader = createBlockHeaderFromBytesArray(header.data, { setHardfork: true })
+    expect(blockHeader.number).toEqual(0n)
+    expect(totalDifficulty.data).toEqual(blockHeader.difficulty)
+  })
+  const valid = await validateERA1(era1File)
+  it('should validate era1 file', () => {
+    expect(valid).toEqual(true)
+  })
+})