[blinkpy] Correctly roundtrip WebDriver test names

Regardless of with or without subtest names

TBR=lpz

Bug: 1000441
Change-Id: I9aa9c773e796b07e4447c6b107f38bea692048a9
Reviewed-on: https://chromium-review.googlesource.com/c/chromium/src/+/1783109Reviewed-by: Robert Ma <robertma@chromium.org>
Commit-Queue: Robert Ma <robertma@chromium.org>
Cr-Commit-Position: refs/heads/master@{#692873}

third_party/blink/tools/blinkpy/web_tests/port/base.py

@@ -1780,22 +1780,32 @@ class Port(object):
                 raise TestRunException(exit_codes.SYS_DEPS_EXIT_STATUS, message)
         return result
 
-    def split_webdriver_test_name(self, test_name):
+    @staticmethod
+    def split_webdriver_test_name(test_name):
         """Splits a WebDriver test name into a filename and a subtest name and
         returns both of them. E.g.
 
-        abd::foo.html -> (abd, foo.html)
+        test.py>>foo.html -> (test.py, foo.html)
+        test.py           -> (test.py, None)
         """
-        separator_index = test_name.find(self.WEBDRIVER_SUBTEST_SEPARATOR)
+        separator_index = test_name.find(Port.WEBDRIVER_SUBTEST_SEPARATOR)
         if separator_index == -1:
-            return test_name
+            return (test_name, None)
         webdriver_test_name = test_name[:separator_index]
-        separator_len = len(self.WEBDRIVER_SUBTEST_SEPARATOR)
+        separator_len = len(Port.WEBDRIVER_SUBTEST_SEPARATOR)
         subtest_suffix = test_name[separator_index + separator_len:]
         return (webdriver_test_name, subtest_suffix)
 
-    def add_webdriver_subtest_suffix(self, test_name, subtest_name):
-        return test_name + self.WEBDRIVER_SUBTEST_SEPARATOR + subtest_name
+    @staticmethod
+    def add_webdriver_subtest_suffix(test_name, subtest_name):
+        """Appends a subtest name to a WebDriver test name. E.g.
+
+        (test.py, foo.html) -> test.py>>foo.html
+        (test.py, None)     -> test.py
+        """
+        if subtest_name:
+            return test_name + Port.WEBDRIVER_SUBTEST_SEPARATOR + subtest_name
+        return test_name
 
 
 class VirtualTestSuite(object):

third_party/blink/tools/blinkpy/web_tests/port/base_unittest.py

@@ -970,23 +970,18 @@ class PortTest(LoggingTestCase):
         self.assertTrue(port.skips_test('failures/expected/image.html'))
 
     def test_split_webdriver_test_name(self):
-        port = self.make_port()
-        webdriver_expectation_name = "tests/accept_alert/accept.py>>foo"
-
-        (wb_test, subtest) = port.split_webdriver_test_name(webdriver_expectation_name)
-
-        self.assertEqual(wb_test, "tests/accept_alert/accept.py")
-        self.assertEqual(subtest, "foo")
+        self.assertEqual(
+            Port.split_webdriver_test_name("tests/accept_alert/accept.py>>foo"),
+            ("tests/accept_alert/accept.py", "foo"))
+        self.assertEqual(
+            Port.split_webdriver_test_name("tests/accept_alert/accept.py"),
+            ("tests/accept_alert/accept.py", None))
 
     def test_add_webdriver_subtest_suffix(self):
-        port = self.make_port()
-        wb_test_name = "abd"
-        sub_test_name = "bar"
-
-        full_webdriver_name = port.add_webdriver_subtest_suffix(wb_test_name, sub_test_name)
-
-        self.assertEqual(full_webdriver_name, "abd>>bar")
-
+        self.assertEqual(
+            Port.add_webdriver_subtest_suffix("abd", "bar"), "abd>>bar")
+        self.assertEqual(
+            Port.add_webdriver_subtest_suffix("abd", None), "abd")
 
     def test_add_webdriver_subtest_suffix(self):
         port = self.make_port()