doc: internal/test/binding for testing

nodejs · Apr 2, 2021 · 2facf36 · 2facf36
1 parent 3ef9562
commit 2facf36
Showing 1 changed file with 9 additions and 0 deletions.
diff --git a/doc/guides/writing-tests.md b/doc/guides/writing-tests.md
@@ -286,6 +286,15 @@ const assert = require('assert');
 const freelist = require('internal/freelist');
 ```
 
+In specific scenarios it may be useful to get a hold of `primordials` or
+`internalBinding()`. You can do so using
+
+```console
+node --expose-internals -r internal/test/binding lib/fs.js
+```
+
+This only works if you preload `internal/test/binding` by command line flag.
+
 ### Assertions
 
 When writing assertions, prefer the strict versions: