testing_ruby.md: Update `make test-all` tips [ci skip]

1 files changed, 7 insertions, 1 deletions

diff --git a/doc/contributing/testing_ruby.md b/doc/contributing/testing_ruby.md
index 6247686efc..167ab55c55 100644
--- a/doc/contributing/testing_ruby.md
+++ b/doc/contributing/testing_ruby.md
@@ -70,7 +70,7 @@ We can run any of the make scripts [in parallel](building_ruby.md#label-Running+
     first the file name, and then the test name, prefixed with `--name`. For example:
 
     ```
-    make test-all TESTS="../test/ruby/test_alias.rb --name=/test_alias_with_zsuper_method/"
+    make test-all TESTS="../test/ruby/test_alias.rb --name=TestAlias#test_alias_with_zsuper_method"
     ```
 
     To run these specs with logs, we can use:
@@ -79,6 +79,12 @@ We can run any of the make scripts [in parallel](building_ruby.md#label-Running+
     make test-all TESTS=-v
     ```
 
+    We can display the help of the `TESTS` option:
+
+    ```
+    $ make test-all TESTS=--help
+    ```
+
     If we would like to run both the `test/` and `bootstraptest/` test suites, we can run
 
     ```