Drop Node.js 16, upgrade minimal 18 and 20, test 21

* Drop support for Node.js 16
* Change expected Node.js 18 to 18.18
* Change expected Node.js 20 to 20.8
* Add Node.js 21 to the test matrix

* Change snapshot tests to compare decompressed bitstreams

The snapshots are compressed differently in Node.js 21. The compression has been stable for many versions but that is not a guarantee, see nodejs/node#50138 for background.

Change tests to compare the decompressed data instead.

Author: novemberborn

.github/workflows/ci.yml

@@ -15,7 +15,7 @@ jobs:
     strategy:
       fail-fast: false
       matrix:
-        node-version: [^16.18, ^18.16, ^20.3]
+        node-version: [^18.18, ^20.8, ^21]
         os: [ubuntu-latest, windows-latest, macos-latest]
     steps:
       - uses: actions/checkout@v3

lib/snapshot-manager.js

@@ -198,7 +198,7 @@ async function encodeSnapshots(snapshotData) {
 	], READABLE_PREFIX.byteLength + VERSION_HEADER.byteLength + SHA_256_HASH_LENGTH + compressed.byteLength);
 }
 
-function decodeSnapshots(buffer, snapPath) {
+export function extractCompressedSnapshot(buffer, snapPath) {
 	if (isLegacySnapshot(buffer)) {
 		throw new LegacyError(snapPath);
 	}
@@ -220,6 +220,12 @@ function decodeSnapshots(buffer, snapPath) {
 	const compressedOffset = sha256sumOffset + SHA_256_HASH_LENGTH;
 	const compressed = buffer.slice(compressedOffset);
 
+	return {version, compressed, sha256sumOffset, compressedOffset};
+}
+
+function decodeSnapshots(buffer, snapPath) {
+	const {compressed, sha256sumOffset, compressedOffset} = extractCompressedSnapshot(buffer, snapPath);
+
 	const sha256sum = crypto.createHash('sha256').update(compressed).digest();
 	const expectedSum = buffer.slice(sha256sumOffset, compressedOffset);
 	if (!sha256sum.equals(expectedSum)) {

package.json

@@ -33,7 +33,7 @@
 	},
 	"type": "module",
 	"engines": {
-		"node": "^16.18 || ^18.16 || ^20.3"
+		"node": "^18.18 || ^20.8 || ^21"
 	},
 	"scripts": {
 		"test": "./scripts/test.sh"
@@ -151,6 +151,6 @@
 		}
 	},
 	"volta": {
-		"node": "20.3.1"
+		"node": "20.8.1"
 	}
 }

test-tap/integration/snapshots.js

@@ -2,11 +2,13 @@ import {Buffer} from 'node:buffer';
 import fs from 'node:fs';
 import path from 'node:path';
 import {fileURLToPath} from 'node:url';
+import {gunzipSync} from 'node:zlib';
 
 import {execa} from 'execa';
 import {test} from 'tap';
 import {temporaryDirectory} from 'tempy';
 
+import {extractCompressedSnapshot} from '../../lib/snapshot-manager.js';
 import {execCli} from '../helper/cli.js';
 
 const __dirname = fileURLToPath(new URL('.', import.meta.url));
@@ -265,9 +267,9 @@ test('snapshots are identical on different platforms', t => {
 		t.ok(fs.existsSync(snapPath));
 
 		const reportContents = fs.readFileSync(reportPath);
-		const snapContents = fs.readFileSync(snapPath);
+		const snapContents = gunzipSync(extractCompressedSnapshot(fs.readFileSync(snapPath)).compressed);
 		const expectedReportContents = fs.readFileSync(expectedReportPath);
-		const expectedSnapContents = fs.readFileSync(expectedSnapPath);
+		const expectedSnapContents = gunzipSync(extractCompressedSnapshot(fs.readFileSync(expectedSnapPath)).compressed);
 
 		t.ok(reportContents.equals(expectedReportContents), 'report file contents matches snapshot');
 		t.ok(snapContents.equals(expectedSnapContents), 'snap file contents matches snapshot');