diff --git a/nixos/doc/manual/development/running-nixos-tests-interactively.xml b/nixos/doc/manual/development/running-nixos-tests-interactively.xml
index b25d3dcb9116..c15ad448317f 100644
--- a/nixos/doc/manual/development/running-nixos-tests-interactively.xml
+++ b/nixos/doc/manual/development/running-nixos-tests-interactively.xml
@@ -19,7 +19,7 @@ starting VDE switch for network 1
 > startAll
 > testScript
 > $machine->succeed("touch /tmp/foo")
-> print($machine->succeed("pwd"), "\n") # Show stdout of command
+> print($machine->succeed("pwd")) # Show stdout of command
 </screen>
   The function <command>testScript</command> executes the entire test script
   and drops you back into the test driver command line upon its completion.
diff --git a/nixos/doc/manual/development/writing-nixos-tests.xml b/nixos/doc/manual/development/writing-nixos-tests.xml
index 983f8f9cbe3e..4a2615c9407b 100644
--- a/nixos/doc/manual/development/writing-nixos-tests.xml
+++ b/nixos/doc/manual/development/writing-nixos-tests.xml
@@ -108,7 +108,7 @@ xlink:href="https://github.com/NixOS/nixpkgs/blob/master/nixos/modules/virtualis
 <programlisting>
 $machine->start;
 $machine->waitForUnit("default.target");
-die unless $machine->succeed("uname") =~ /Linux/;
+$machine->succeed("uname") =~ /Linux/ or die;
 </programlisting>
   The first line is actually unnecessary; machines are implicitly started when
   you first execute an action on them (such as <literal>waitForUnit</literal>