write snapshot file when missing

Author: rluvaton

test/common/assertSnapshot.js

@@ -39,9 +39,8 @@ async function assertSnapshot(actual, filename = process.argv[1]) {
       expected = await fs.readFile(snapshot, 'utf8');
     } catch (e) {
       if (e.code === 'ENOENT') {
-        console.log(
-          'Snapshot file does not exist. You can create a new one by running the test with NODE_REGENERATE_SNAPSHOTS=1',
-        );
+        await fs.writeFile(snapshot, actual);
+        return;
       }
       throw e;
     }