test: Add rudimentary support to run selected tests only

To keep this simple, only support tests that have corresponding setup
and teardown functions implied by their path. For example:

  ./run passt/ndp

will trigger the 'passt' setup and teardown functions.

This is not really elegant, but it looks robust, and while David is
considering proper alternatives, it should be quite useful.

Signed-off-by: Stefano Brivio <sbrivio@redhat.com>
Reviewed-by: David Gibson <david@gibson.dropbear.id.au>

1 files changed, 16 insertions, 0 deletions

diff --git a/test/README.md b/test/README.md
index 72a4986..09ad05d 100644
--- a/test/README.md
+++ b/test/README.md
@@ -85,6 +85,22 @@ variable settings: DEBUG=1 enables debugging messages, TRACE=1 enables tracing
 
     PCAP=1 TRACE=1 ./run
 
+## Running selected tests
+
+Rudimentary support to run a list of selected tests, without support for
+dependencies, is available. Tests need to have a setup function corresponding to
+their path. For example:
+
+    ./run passt/ndp passt/dhcp pasta/ndp
+
+will call the 'passt' setup function (from lib/setup), run the two corresponding
+tests, call the 'passt' teardown function, the 'pasta' setup, run the pasta/ndp
+test, and finally tear down the 'pasta' setup.
+
+Note that requirements on steps implemented by related tests are not handled.
+For example, if the 'passt/tcp' needs guest connectivity set up by the
+'passt/ndp' and 'passt/dhcp' tests, those need to be listed explicitly.
+
 ## Continuous integration
 
 Issuing: