PY-23549: run files as scripts for py3 unittest (instead of "discovery" engine used for py2)

In Py3 it is possible to run script directly which is much more stable than discovery machinery
For example it supports hyphens in file names

python/helpers/pycharm/_jb_unittest_runner.py

@@ -1,5 +1,6 @@
 # coding=utf-8
 import os
+import sys
 from unittest import main
 
 from _jb_runner_tools import jb_start_tests, jb_doc_args
@@ -10,16 +11,21 @@ if __name__ == '__main__':
 
     args = ["python -m unittest"]
     if path:
-        discovery_args = ["discover", "-s"]
-        # Unittest does not support script directly, but it can use "discover" to find all tests in some folder
-        # filtering by script
         assert os.path.exists(path), "{0}: No such file or directory".format(path)
-        if os.path.isfile(path):
-            discovery_args += [os.path.dirname(path), "-p", os.path.basename(path)]
+        if sys.version_info > (3, 0) and os.path.isfile(path):
+            # In Py3 it is possible to run script directly which is much more stable than discovery machinery
+            # For example it supports hyphens in file names PY-23549
+            additional_args = [path] + additional_args
         else:
-            discovery_args.append(path)
-        discovery_args += ["-t", os.getcwd()]  # To force unit calculate path relative to this folder
-        additional_args = discovery_args + additional_args
+            discovery_args = ["discover", "-s"]
+            # Unittest in py2 does not support running script directly (and folders in py2 and py3),
+            # but it can use "discover" to find all tests in some folder (optionally filtering by script)
+            if os.path.isfile(path):
+                discovery_args += [os.path.dirname(path), "-p", os.path.basename(path)]
+            else:
+                discovery_args.append(path)
+            discovery_args += ["-t", os.getcwd()]  # To force unit calculate path relative to this folder
+            additional_args = discovery_args + additional_args
     elif targets:
         additional_args += targets
     args += additional_args

python/testData/testRunner/env/unit/withHyphen/test-foobar.py

@@ -0,0 +1,26 @@
+#!/usr/bin/env python
+
+# from falcon import testing
+import unittest
+
+
+# class TestAPI(testing.TestCase):
+
+class TestAPI(unittest.TestCase):
+    def setUp(self):
+
+        super().setUp()
+
+
+class TestCoverage(TestAPI):
+    def test_first(self):
+
+        self.assertTrue(1 == 1)
+
+    def test_second(self):
+
+        self.assertFalse(1 == 1)
+
+
+if __name__ == '__main__':
+    unittest.main()

python/testSrc/com/jetbrains/env/python/testing/PythonUnitTestingTest.java

@@ -23,7 +23,6 @@ import com.intellij.openapi.vfs.VirtualFile;
 import com.intellij.testFramework.EdtTestUtil;
 import com.intellij.testFramework.fixtures.CodeInsightTestFixture;
 import com.jetbrains.env.EnvTestTagsRequired;
-import com.jetbrains.env.ProcessWithConsoleRunner;
 import com.jetbrains.env.PyEnvTestCase;
 import com.jetbrains.env.ut.PyUnitTestProcessRunner;
 import com.jetbrains.python.PyBundle;
@@ -60,6 +59,41 @@ public final class PythonUnitTestingTest extends PyEnvTestCase {
     });
   }
 
+
+  /**
+   * Make sure test rerun works when pattern is enabled (PY-23416)
+   */
+  @Test
+  @EnvTestTagsRequired(tags = "python3")
+  public void testScriptWithHyphen() throws Exception {
+    runPythonTest(new PyUnitTestProcessWithConsoleTestTask("testRunner/env/unit/withHyphen", "test-foobar.py") {
+
+      @NotNull
+      @Override
+      protected PyUnitTestProcessRunner createProcessRunner() throws Exception {
+        return new PyUnitTestProcessRunner(toFullPath(myScriptName), 1);
+      }
+
+      @Override
+      protected void checkTestResults(@NotNull final PyUnitTestProcessRunner runner,
+                                      @NotNull final String stdout,
+                                      @NotNull final String stderr,
+                                      @NotNull final String all) {
+        if (runner.getCurrentRerunStep() == 0) {
+          Assert.assertEquals(runner.getFormattedTestTree(), 2, runner.getAllTestsCount());
+          Assert.assertEquals(runner.getFormattedTestTree(), 1, runner.getPassedTestsCount());
+          Assert.assertEquals(runner.getFormattedTestTree(), 1, runner.getFailedTestsCount());
+        }
+        else {
+          Assert.assertEquals(runner.getFormattedTestTree(), 1, runner.getAllTestsCount());
+          Assert.assertEquals(runner.getFormattedTestTree(), 0, runner.getPassedTestsCount());
+          Assert.assertEquals(runner.getFormattedTestTree(), 1, runner.getFailedTestsCount());
+        }
+      }
+    });
+  }
+
+
   /**
    * Make sure test rerun works when pattern is enabled (PY-23416)
    */
@@ -73,7 +107,8 @@ public final class PythonUnitTestingTest extends PyEnvTestCase {
         // Full pass is required because it is folder
         return new PyUnitTestProcessRunner(toFullPath(myScriptName), 2) {
           @Override
-          protected void configurationCreatedAndWillLaunch(@NotNull final PyUniversalUnitTestConfiguration configuration) throws IOException {
+          protected void configurationCreatedAndWillLaunch(@NotNull final PyUniversalUnitTestConfiguration configuration)
+            throws IOException {
             super.configurationCreatedAndWillLaunch(configuration);
             configuration.setPattern("test*");
           }
@@ -100,7 +135,7 @@ public final class PythonUnitTestingTest extends PyEnvTestCase {
    */
   @Test
   public void testRunModuleAsFile() throws Exception {
-    runPythonTest(new RunModuleAsFileTask<PyUnitTestProcessRunner>(){
+    runPythonTest(new RunModuleAsFileTask<PyUnitTestProcessRunner>() {
       @NotNull
       @Override
       protected PyUnitTestProcessRunner createProcessRunner() throws Exception {