tests/avocado: Share useful helpers from virtiofs_submounts test

Move the useful has_cmd()/has_cmds() helpers from the virtiofs
test to the avocado_qemu public class.

Reviewed-by: Wainer dos Santos Moschetta <wainersm@redhat.com>
Reviewed-by: Willian Rampazzo <willianr@redhat.com>
Signed-off-by: Philippe Mathieu-Daudé <f4bug@amsat.org>
Message-Id: <20211105143416.148332-5-f4bug@amsat.org>

1 files changed, 57 insertions, 0 deletions

diff --git a/tests/avocado/avocado_qemu/__init__.py b/tests/avocado/avocado_qemu/__init__.py
index e46b3ecb89..1efc22dabf 100644
--- a/tests/avocado/avocado_qemu/__init__.py
+++ b/tests/avocado/avocado_qemu/__init__.py
@@ -11,6 +11,7 @@
 import logging
 import os
 import shutil
+import subprocess
 import sys
 import tempfile
 import time
@@ -41,6 +42,62 @@ from qemu.utils import (get_info_usernet_hostfwd_port, kvm_available,
                         tcg_available)
 
 
+def has_cmd(name, args=None):
+    """
+    This function is for use in a @avocado.skipUnless decorator, e.g.:
+
+        @skipUnless(*has_cmd('sudo -n', ('sudo', '-n', 'true')))
+        def test_something_that_needs_sudo(self):
+            ...
+    """
+
+    if args is None:
+        args = ('which', name)
+
+    try:
+        _, stderr, exitcode = run_cmd(args)
+    except Exception as e:
+        exitcode = -1
+        stderr = str(e)
+
+    if exitcode != 0:
+        cmd_line = ' '.join(args)
+        err = f'{name} required, but "{cmd_line}" failed: {stderr.strip()}'
+        return (False, err)
+    else:
+        return (True, '')
+
+def has_cmds(*cmds):
+    """
+    This function is for use in a @avocado.skipUnless decorator and
+    allows checking for the availability of multiple commands, e.g.:
+
+        @skipUnless(*has_cmds(('cmd1', ('cmd1', '--some-parameter')),
+                              'cmd2', 'cmd3'))
+        def test_something_that_needs_cmd1_and_cmd2(self):
+            ...
+    """
+
+    for cmd in cmds:
+        if isinstance(cmd, str):
+            cmd = (cmd,)
+
+        ok, errstr = has_cmd(*cmd)
+        if not ok:
+            return (False, errstr)
+
+    return (True, '')
+
+def run_cmd(args):
+    subp = subprocess.Popen(args,
+                            stdout=subprocess.PIPE,
+                            stderr=subprocess.PIPE,
+                            universal_newlines=True)
+    stdout, stderr = subp.communicate()
+    ret = subp.returncode
+
+    return (stdout, stderr, ret)
+
 def is_readable_executable_file(path):
     return os.path.isfile(path) and os.access(path, os.R_OK | os.X_OK)