manual: re-add running nixos tests sections

1 files changed, 43 insertions, 0 deletions

diff --git a/nixos/doc/manual/development/running-nixos-tests-interactively.xml b/nixos/doc/manual/development/running-nixos-tests-interactively.xml
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+++ b/nixos/doc/manual/development/running-nixos-tests-interactively.xml
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+<section xmlns="http://docbook.org/ns/docbook"
+        xmlns:xlink="http://www.w3.org/1999/xlink"
+        xmlns:xi="http://www.w3.org/2001/XInclude"
+        version="5.0"
+        xml:id="sec-running-nixos-tests">
+<title>Running Tests interactively</title>
+
+<para>The test itself can be run interactively.  This is
+particularly useful when developing or debugging a test:
+
+<screen>
+$ nix-build nixos/tests/login.nix -A driver
+$ ./result/bin/nixos-test-driver
+starting VDE switch for network 1
+&gt;
+</screen>
+
+You can then take any Perl statement, e.g.
+
+<screen>
+&gt; startAll
+&gt; testScript
+&gt; $machine->succeed("touch /tmp/foo")
+</screen>
+
+The function <command>testScript</command> executes the entire test
+script and drops you back into the test driver command line upon its
+completion.  This allows you to inspect the state of the VMs after the
+test (e.g. to debug the test script).</para>
+
+<para>To just start and experiment with the VMs, run:
+
+<screen>
+$ nix-build nixos/tests/login.nix -A driver
+$ ./result/bin/nixos-run-vms
+</screen>
+
+The script <command>nixos-run-vms</command> starts the virtual
+machines defined by test.  The root file system of the VMs is created
+on the fly and kept across VM restarts in
+<filename>./</filename><varname>hostname</varname><filename>.qcow2</filename>.</para>
+
+</section>