testnode: use PATH instead of command-line options to provide extra binaries

The /bin/ folder of all extra SR provided by the testnode are added to PATH.
SR must fixed either by moving executables or adding symlinks.

The testnode will stop looking at the parameter list of runTestSuite,
and --firefox_bin/--xvfb_bin are deprecated.

This is part of defining a generic and unique API between the testnode and
the tested software.

erp5/util/testnode/ProcessManager.py

@@ -160,7 +160,7 @@ class ProcessManager(object):
     if new_session:
       subprocess_kw['preexec_fn'] = os.setsid
     raise_error_if_fail = kw.pop('raise_error_if_fail', True)
-    env = kw and dict(os.environ, **kw) or None
+    env = dict(os.environ, **kw) if kw else None
     command = format_command(*args, **kw)
     logger.info('subprocess_kw : %r', subprocess_kw)
     logger.info('$ %s', command)

erp5/util/testnode/UnitTestRunner.py

@@ -139,18 +139,22 @@ class UnitTestRunner(object):
       '--revision', node_test_suite.revision,
       '--test_suite', node_test_suite.test_suite,
       '--test_suite_title', node_test_suite.test_suite_title)
+    soft = config['slapos_directory'] + '/soft/'
+    software_list = [soft + md5digest(x) for x in config['software_list']]
+    PATH = os.getenv('PATH', '')
+    PATH = ':'.join(x + '/bin' for x in software_list) + (PATH and ':' + PATH)
     supported_parameter_set = set(self.testnode.process_manager
       .getSupportedParameterList(run_test_suite_path))
-    def part(path):
-        path = config['slapos_directory'] + '/soft/%s/parts/' + path
-        path, = filter(os.path.exists, (path % md5digest(software)
-            for software in config['software_list']))
+    def path(name, compat): # BBB
+        path, = filter(os.path.exists, (base + relative
+          for relative in ('/bin/' + name, '/parts/' + compat)
+          for base in software_list))
         return path
     for option, value in (
-        ('--firefox_bin', lambda: part('firefox/firefox-slapos')),
+        ('--firefox_bin', lambda: path('firefox', 'firefox/firefox-slapos')),
         ('--frontend_url', lambda: config['frontend_url']),
         ('--node_quantity', lambda: config['node_quantity']),
-        ('--xvfb_bin', lambda: part('xserver/bin/Xvfb')),
+        ('--xvfb_bin', lambda: path('xvfb', 'xserver/bin/Xvfb')),
         ):
       if option in supported_parameter_set:
         invocation_list += option, value()
@@ -165,7 +169,7 @@ class UnitTestRunner(object):
     # result. We only do cleanup if the test runner itself is not able
     # to run.
     createFolder(node_test_suite.test_suite_directory, clean=True)
-    self.testnode.process_manager.spawn(*invocation_list,
+    self.testnode.process_manager.spawn(*invocation_list, PATH=PATH,
                           cwd=node_test_suite.test_suite_directory,
                           log_prefix='runTestSuite', get_output=False)