make test: separate test discovery code

Separating test discovery code to it's own script file has the
advantage of easily doing e.g. listing of all existing tests.

Change-Id: I80dc280263cc7e33e7e13cb0d48b39bf08ece24d
Signed-off-by: Klement Sekera <ksekera@cisco.com>

2 files changed, 68 insertions, 34 deletions

diff --git a/test/discover_tests.py b/test/discover_tests.py
new file mode 100755
index 00000000000..eea594107b6
--- /dev/null
+++ b/test/discover_tests.py
@@ -0,0 +1,57 @@
+#!/usr/bin/env python
+
+import sys
+import os
+import unittest
+import importlib
+import argparse
+
+
+def discover_tests(directory, callback):
+    do_insert = True
+    for _f in os.listdir(directory):
+        f = "%s/%s" % (directory, _f)
+        if os.path.isdir(f):
+            discover_tests(f, callback)
+            continue
+        if not os.path.isfile(f):
+            continue
+        if do_insert:
+            sys.path.insert(0, directory)
+            do_insert = False
+        if not _f.startswith("test_") or not _f.endswith(".py"):
+            continue
+        name = "".join(f.split("/")[-1].split(".")[:-1])
+        if name in sys.modules:
+            raise Exception("Duplicate test module `%s' found!" % name)
+        module = importlib.import_module(name)
+        for name, cls in module.__dict__.items():
+            if not isinstance(cls, type):
+                continue
+            if not issubclass(cls, unittest.TestCase):
+                continue
+            if name == "VppTestCase":
+                continue
+            for method in dir(cls):
+                if not callable(getattr(cls, method)):
+                    continue
+                if method.startswith("test_"):
+                    callback(_f, cls, method)
+
+
+def print_callback(file_name, cls, method):
+    print("%s.%s.%s" % (file_name, cls.__name__, method))
+
+
+if __name__ == '__main__':
+    parser = argparse.ArgumentParser(description="Discover VPP unit tests")
+    parser.add_argument("-d", "--dir", action='append', type=str,
+                        help="directory containing test files "
+                             "(may be specified multiple times)")
+    args = parser.parse_args()
+    if args.dir is None:
+        args.dir = "."
+
+    suite = unittest.TestSuite()
+    for d in args.dir:
+        discover_tests(d, print_callback)
diff --git a/test/run_tests.py b/test/run_tests.py
index 271f5c5c60d..9614080d977 100644
--- a/test/run_tests.py
+++ b/test/run_tests.py
@@ -5,43 +5,11 @@ import os
 import select
 import unittest
 import argparse
-import importlib
 from multiprocessing import Process, Pipe
 from framework import VppTestRunner
 from debug import spawn_gdb
 from log import global_logger
-
-
-def add_from_dir(suite, directory):
-    do_insert = True
-    for _f in os.listdir(directory):
-        f = "%s/%s" % (directory, _f)
-        if os.path.isdir(f):
-            add_from_dir(suite, f)
-            continue
-        if not os.path.isfile(f):
-            continue
-        if do_insert:
-            sys.path.insert(0, directory)
-            do_insert = False
-        if not _f.startswith("test_") or not _f.endswith(".py"):
-            continue
-        name = "".join(f.split("/")[-1].split(".")[:-1])
-        if name in sys.modules:
-            raise Exception("Duplicate test module `%s' found!" % name)
-        module = importlib.import_module(name)
-        for name, cls in module.__dict__.items():
-            if not isinstance(cls, type):
-                continue
-            if not issubclass(cls, unittest.TestCase):
-                continue
-            if name == "VppTestCase":
-                continue
-            for method in dir(cls):
-                if not callable(getattr(cls, method)):
-                    continue
-                if method.startswith("test_"):
-                    suite.addTest(cls(method))
+from discover_tests import discover_tests
 
 
 def test_runner_wrapper(suite, keep_alive_pipe, result_pipe):
@@ -54,6 +22,14 @@ def test_runner_wrapper(suite, keep_alive_pipe, result_pipe):
     keep_alive_pipe.close()
 
 
+class add_to_suite_callback:
+    def __init__(self, suite):
+        self.suite = suite
+
+    def __call__(self, file_name, cls, method):
+        suite.addTest(cls(method))
+
+
 def run_forked(suite):
     keep_alive_parent_end, keep_alive_child_end = Pipe(duplex=False)
     result_parent_end, result_child_end = Pipe(duplex=False)
@@ -124,9 +100,10 @@ if __name__ == '__main__':
     failfast = True if args.failfast == 1 else False
 
     suite = unittest.TestSuite()
+    cb = add_to_suite_callback(suite)
     for d in args.dir:
         global_logger.info("Adding tests from directory tree %s" % d)
-        add_from_dir(suite, d)
+        discover_tests(d, cb)
 
     if debug is None or debug.lower() not in ["gdb", "gdbserver"]:
         sys.exit(run_forked(suite))