luatest: allow to run test cases in parallel

lib/luatest_server.py

@@ -3,6 +3,7 @@
 import re
 import sys
 
+from subprocess import PIPE
 from subprocess import Popen
 from threading import Timer
 
@@ -14,6 +15,8 @@
 from lib.tarantool_server import Test
 from lib.tarantool_server import TestExecutionError
 from lib.tarantool_server import TarantoolServer
+from lib.utils import bytes_to_str
+from lib.utils import find_tags
 
 
 def timeout_handler(process, test_timeout):
@@ -52,6 +55,10 @@ def execute(self, server):
             for p in Options().args.pattern:
                 command.extend(['--pattern', p])
 
+        # Run a specific test case. See find_tests() for details.
+        if 'test_case' in self.run_params:
+            command.extend(['--run-test-case', self.run_params['test_case']])
+
         # We start luatest from the project source directory, it
         # is the usual way to use luatest.
         #
@@ -137,22 +144,82 @@ def verify_luatest_exe(cls):
             # those cases, which are childs of OSError anyway.
             raise TestRunInitError('Unable to find luatest executable', e)
 
+    @classmethod
+    def test_cases(cls, test_name):
+        p = Popen([cls.luatest, test_name, '--list-test-cases'], stdout=PIPE)
+        output = bytes_to_str(p.stdout.read()).rstrip()
+        p.wait()
+
+        # Exclude the first line if it is a tarantool version
+        # report.
+        res = output.split('\n')
+        if len(res) > 0 and res[0].startswith('Tarantool version is'):
+            return res[1:]
+
+        return res
+
     @staticmethod
     def find_tests(test_suite, suite_path):
         """Looking for *_test.lua, which are can be executed by luatest."""
 
-        def patterned(test, patterns):
-            answer = []
-            for i in patterns:
-                if test.name.find(i) != -1:
-                    answer.append(test)
-            return answer
-
+        # TODO: Investigate why this old hack is needed and drop
+        # it if possible (move the assignment to test_suite.py).
+        #
+        # cdc70f94701f suggests that it is related to the out of
+        # source build.
         test_suite.ini['suite'] = suite_path
-        tests = glob.glob(os.path.join(suite_path, '*_test.lua'))
 
-        tests = Server.exclude_tests(tests, test_suite.args.exclude)
-        test_suite.tests = [LuatestTest(k, test_suite.args, test_suite.ini)
-                            for k in sorted(tests)]
-        test_suite.tests = sum([patterned(x, test_suite.args.tests)
-                                for x in test_suite.tests], [])
+        # A pattern here means just a substring to find in a test
+        # name.
+        include_patterns = Options().args.tests
+        exclude_patterns = Options().args.exclude
+
+        accepted_tags = Options().args.tags
+
+        tests = []
+        for test_name in glob.glob(os.path.join(suite_path, '*_test.lua')):
+            # If neither of the include patterns are substrings of
+            # the given test name, skip the test.
+            if not any(p in test_name for p in include_patterns):
+                continue
+
+            # If at least one of the exclude patterns is a
+            # substring of the given test name, skip the test.
+            if any(p in test_name for p in exclude_patterns):
+                continue
+
+            tags = find_tags(test_name)
+
+            # If --tags <...> CLI option is provided...
+            if accepted_tags:
+                # ...and the test has neither of the given tags,
+                # skip the test.
+                if not any(t in accepted_tags for t in tags):
+                    continue
+
+            # Add the test to the execution list otherwise.
+            if 'parallel' in tags:
+                # If the test has the 'parallel' tag, split the
+                # test to test cases to run in separate tasks in
+                # parallel.
+                test_cases = LuatestServer.test_cases(test_name)
+
+                # Display shorter test case names on the screen:
+                # strip the common prefix.
+                prefix_len = len(os.path.commonprefix(test_cases))
+
+                for test_case in test_cases:
+                    tests.append(LuatestTest(test_name, test_suite.args, test_suite.ini,
+                                             params={"test_case": test_case},
+                                             conf_name=test_case[prefix_len:]))
+            else:
+                # If the test has no 'parallel' tag, run all the
+                # test cases as one task.
+                tests.append(LuatestTest(test_name, test_suite.args, test_suite.ini))
+
+        tests.sort(key=lambda t: t.name)
+
+        # TODO: Don't modify a test suite object's field from
+        # another object directly. It is much better to just
+        # return a list of tests from this method.
+        test_suite.tests = tests