[blinkpy] Switch to run WPT subcommands using Python3

Upstream WPT is now Python 3-first. To minimize the likelihood of
Chromium engineers writing incompatible tests*, we should run the WPT
parts of blinkpy under Python 3.

* Or, more likely, incompatible Python file handlers
(https://web-platform-tests.org/writing-tests/python-handlers/index.html)

Bug: 1135554
Change-Id: I9813a81543219ede80bb58de971d2e4509ef4b53
Reviewed-on: https://chromium-review.googlesource.com/c/chromium/src/+/2558741
Commit-Queue: Stephen McGruer <smcgruer@chromium.org>
Reviewed-by: Robert Ma <robertma@chromium.org>
Reviewed-by: Adam Rice <ricea@chromium.org>
Cr-Commit-Position: refs/heads/master@{#835668}

third_party/blink/tools/blinkpy/w3c/test_importer.py

@@ -404,7 +404,8 @@ class TestImporter(object):
         stages the generated MANIFEST.json in the git index, ready to commit.
         """
         _log.info('Generating MANIFEST.json')
-        WPTManifest.generate_manifest(self.host, self.dest_path)
+        WPTManifest.generate_manifest(self.host.port_factory.get(),
+                                      self.dest_path)
         manifest_path = self.fs.join(self.dest_path, 'MANIFEST.json')
         assert self.fs.exists(manifest_path)
         manifest_base_path = self.fs.normpath(

third_party/blink/tools/blinkpy/w3c/test_importer_unittest.py

@@ -25,12 +25,12 @@ from blinkpy.web_tests.port.android import PRODUCTS_TO_EXPECTATION_FILE_PATHS
 
 MOCK_WEB_TESTS = '/mock-checkout/' + RELATIVE_WEB_TESTS
 MANIFEST_INSTALL_CMD = [
-    'python',
+    'python3',
     '/mock-checkout/third_party/blink/tools/blinkpy/third_party/wpt/wpt/wpt',
-    'manifest',
-    '--no-download',
-    '--tests-root',
-    MOCK_WEB_TESTS + 'external/wpt']
+    'manifest', '--no-download', '--tests-root',
+    MOCK_WEB_TESTS + 'external/wpt'
+]
+
 
 class TestImporterTest(LoggingTestCase):
 

third_party/blink/tools/blinkpy/w3c/wpt_manifest.py

@@ -314,7 +314,7 @@ class WPTManifest(object):
                 _log.error('Manifest base not found at "%s".',
                            base_manifest_path)
 
-        WPTManifest.generate_manifest(port.host, wpt_path)
+        WPTManifest.generate_manifest(port, wpt_path)
 
         if fs.isfile(manifest_path):
             _log.debug('Manifest generation completed.')
@@ -325,17 +325,17 @@ class WPTManifest(object):
             fs.write_text_file(manifest_path, '{}')
 
     @staticmethod
-    def generate_manifest(host, dest_path):
+    def generate_manifest(port, dest_path):
         """Generates MANIFEST.json on the specified directory."""
-        wpt_exec_path = PathFinder(host.filesystem).path_from_blink_tools(
+        wpt_exec_path = PathFinder(port.host.filesystem).path_from_blink_tools(
             'blinkpy', 'third_party', 'wpt', 'wpt', 'wpt')
         cmd = [
-            'python', wpt_exec_path, 'manifest', '--no-download',
+            port.python3_command(), wpt_exec_path, 'manifest', '--no-download',
             '--tests-root', dest_path
         ]
 
         # ScriptError will be raised if the command fails.
-        host.executive.run_command(
+        port.host.executive.run_command(
             cmd,
             # This will also include stderr in the exception message.
             return_stderr=True)

third_party/blink/tools/blinkpy/w3c/wpt_manifest_unittest.py

@@ -24,7 +24,7 @@ class WPTManifestUnitTest(unittest.TestCase):
                          {manifest_path: '{"manifest": "base"}'})
 
         self.assertEqual(host.executive.calls, [[
-            'python',
+            'python3',
             '/mock-checkout/third_party/blink/tools/blinkpy/third_party/wpt/wpt/wpt',
             'manifest',
             '--no-download',
@@ -47,7 +47,7 @@ class WPTManifestUnitTest(unittest.TestCase):
                          {manifest_path: '{"manifest": "base"}'})
 
         self.assertEqual(host.executive.calls, [[
-            'python',
+            'python3',
             '/mock-checkout/third_party/blink/tools/blinkpy/third_party/wpt/wpt/wpt',
             'manifest',
             '--no-download',
@@ -68,7 +68,7 @@ class WPTManifestUnitTest(unittest.TestCase):
         port = TestPort(host)
         WPTManifest.ensure_manifest(port, 'wpt_internal')
         self.assertEqual(host.executive.calls, [[
-            'python',
+            'python3',
             '/mock-checkout/third_party/blink/tools/blinkpy/third_party/wpt/wpt/wpt',
             'manifest',
             '--no-download',

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

@@ -1221,6 +1221,18 @@ class Port(object):
     def architecture(self):
         return self._architecture
 
+    def python3_command(self):
+        """Returns the correct command to use to run python3.
+
+        This exists because Windows has inconsistent behavior between the bots
+        and local developer machines, such that determining which python3 name
+        to use is non-trivial. See https://crbug.com/155616.
+
+        Once blinkpy runs under python3, this can be removed in favour of
+        callers using sys.executable.
+        """
+        return 'python3'
+
     def get_option(self, name, default_value=None):
         return getattr(self._options, name, default_value)
 

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

@@ -29,6 +29,7 @@
 
 import errno
 import logging
+import os
 import tempfile
 
 # The _winreg library is only available on Windows.
@@ -39,6 +40,7 @@ except ImportError:
     _winreg = None  # pylint: disable=invalid-name
 
 from blinkpy.common import exit_codes
+from blinkpy.common.memoized import memoized
 from blinkpy.web_tests.breakpad.dump_reader_win import DumpReaderWin
 from blinkpy.web_tests.models import test_run_results
 from blinkpy.web_tests.port import base
@@ -169,6 +171,24 @@ class WinPort(base.Port):
     def operating_system(self):
         return 'win'
 
+    @memoized
+    def python3_command(self):
+        # The subprocess module on Windows does not look at PATHEXT, so we
+        # cannot rely on 'python3' working. Instead, we must check each possible
+        # program name to find the working one.
+        _log.debug('Searching for Python 3 command name')
+
+        exts = filter(len, os.getenv('PATHEXT', '').split(';'))
+        for ext in [''] + exts:
+            python = 'python3%s' % ext
+            _log.debug('Trying "%s"' % python)
+            try:
+                self._executive.run_command([python, '--version'])
+                return python
+            except WindowsError:
+                pass
+        raise WindowsError('Unable to find a valid python3 command name')
+
     def relative_test_filename(self, filename):
         path = filename[len(self.web_tests_dir()) + 1:]
         return path.replace('\\', '/')

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

@@ -26,7 +26,11 @@
 # (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
 # OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
 
+import functools
+import mock
 import optparse
+import sys
+import unittest
 
 from blinkpy.common.system import output_capture
 from blinkpy.common.system.executive_mock import MockExecutive
@@ -108,6 +112,41 @@ class WinPortTest(port_testcase.PortTestCase):
     def test_operating_system(self):
         self.assertEqual('win', self.make_port().operating_system())
 
+    @unittest.skipIf(sys.platform != 'win32',
+                     'Needs WindowsError to be defined')
+    def test_python3_command(self):
+        def run_command_fn(valid_python, args):
+            if args[0] != valid_python:
+                raise WindowsError('%s != %s' % (valid_python, args[0]))
+            return 0
+
+        with mock.patch('os.getenv', return_value='.BAT;.EXE;.COM'):
+            # Simple case: one of the extensions match.
+            port = self.make_port()
+            port._executive = MockExecutive(run_command_fn=functools.partial(
+                run_command_fn, 'python3.EXE'))
+            self.assertEqual('python3.EXE', port.python3_command())
+
+            # Ensure that the code checks for python3 without an extension.
+            port = self.make_port()
+            port._executive = MockExecutive(
+                run_command_fn=functools.partial(run_command_fn, 'python3'))
+            self.assertEqual('python3', port.python3_command())
+
+            # If there are no matches, a WindowsError should be raised.
+            port = self.make_port()
+            port._executive = MockExecutive(
+                run_command_fn=functools.partial(run_command_fn, None))
+            with self.assertRaises(WindowsError):
+                port.python3_command()
+
+    @unittest.skipIf(sys.platform != 'win32', 'Smoketest for Windows only')
+    def test_python3_command_smoketest(self):
+        # This is a smoketest to make sure that depot_tools has ensured a valid
+        # Python 3 is available. If this test fails on a machine, it means that
+        # there is something wrong with the Python 3 setup.
+        self.assertIsNotNone(self.make_port().python3_command())
+
     def test_driver_name_option(self):
         self.assertTrue(
             self.make_port()._path_to_driver().endswith('content_shell.exe'))

third_party/blink/tools/blinkpy/web_tests/servers/wptserve.py

@@ -62,8 +62,14 @@ class WPTServe(server_base.ServerBase):
                                       'handlers')
         wpt_script = fs.join(path_to_wpt_root, 'wpt')
         start_cmd = [
-            self._port_obj.host.executable, '-u', wpt_script, 'serve',
-            '--config', self._config_file, '--doc_root', path_to_wpt_tests,
+            self._port_obj.python3_command(),
+            '-u',
+            wpt_script,
+            'serve',
+            '--config',
+            self._config_file,
+            '--doc_root',
+            path_to_wpt_tests,
             '--no-h2',
         ]
 

third_party/blink/tools/blinkpy/web_tests/servers/wptserve_unittest.py

@@ -25,7 +25,7 @@ class TestWPTServe(LoggingTestCase):
     def test_init_start_cmd_without_ws_handlers(self):
         server = WPTServe(self.port, '/foo')
         self.assertEqual(server._start_cmd, [
-            'python',
+            'python3',
             '-u',
             '/mock-checkout/third_party/blink/tools/blinkpy/third_party/wpt/wpt/wpt',
             'serve',
@@ -41,7 +41,7 @@ class TestWPTServe(LoggingTestCase):
             '/test.checkout/wtests/external/wpt/websockets/handlers')
         server = WPTServe(self.port, '/foo')
         self.assertEqual(server._start_cmd, [
-            'python',
+            'python3',
             '-u',
             '/mock-checkout/third_party/blink/tools/blinkpy/third_party/wpt/wpt/wpt',
             'serve',

third_party/blink/web_tests/TestExpectations

@@ -47,6 +47,11 @@ crbug.com/1048761 external/wpt/infrastructure/server/wpt-server-http.sub.html [
 # WPT Test harness doesn't deal with finding an about:blank ref test
 crbug.com/1066130 external/wpt/infrastructure/assumptions/blank.html [ Failure ]
 
+# When running under Python 3 on Windows, this test fails to activate backpressure.
+crbug.com/1155106 external/wpt/websockets/stream/tentative/backpressure-receive.any.html [ Failure ]
+crbug.com/1155106 external/wpt/websockets/stream/tentative/backpressure-receive.any.worker.html [ Failure ]
+crbug.com/1155106 external/wpt/websockets/stream/tentative/backpressure-receive.any.sharedworker.html [ Failure ]
+
 # Favicon is not supported by run_web_tests.
 external/wpt/fetch/metadata/favicon.https.sub.html [ Skip ]
 

third_party/blink/web_tests/external/PRESUBMIT.py

@@ -9,6 +9,27 @@ for more details about the presubmit API built into depot_tools.
 """
 
 
+def python3_command(input_api):
+    if not input_api.is_windows:
+        return 'python3'
+
+    # The subprocess module on Windows does not look at PATHEXT, so we cannot
+    # rely on 'python3' working. Instead we must check each possible name to
+    # find the working one.
+    input_api.logging.debug('Searching for Python 3 command name')
+
+    exts = filter(len, input_api.environ.get('PATHEXT', '').split(';'))
+    for ext in [''] + exts:
+        python = 'python3%s' % ext
+        input_api.logging.debug('Trying "%s"' % python)
+        try:
+            input_api.subprocess.check_output([python, '--version'])
+            return python
+        except WindowsError:
+            pass
+    raise WindowsError('Unable to find a valid python3 command name')
+
+
 def _LintWPT(input_api, output_api):
     """Lint functionality duplicated from web-platform-tests upstream.
 
@@ -32,7 +53,7 @@ def _LintWPT(input_api, output_api):
         return []
 
     args = [
-        input_api.python_executable,
+        python3_command(input_api),
         linter_path,
         'lint',
         '--repo-root=%s' % wpt_path,

third_party/blink/web_tests/external/PRESUBMIT_test.py

@@ -20,6 +20,9 @@ class MockInputApi(object):
         self.os_path = os.path
         self.python_executable = sys.executable
         self.subprocess = subprocess
+        self.is_windows = sys.platform == 'win32'
+        self.environ = os.environ
+        self.logging = PrintLogger()
 
     def AbsoluteLocalPaths(self):
         return self.affected_paths
@@ -32,6 +35,13 @@ class MockInputApi(object):
         return filter(lambda f: filter_func(f), all_files)
 
 
+class PrintLogger(object):
+    """A simple logger that just prints log messages."""
+
+    def debug(self, message):
+        print(message)
+
+
 class MockPresubmitError(object):
     """A minimal mock of an error class for our checks."""
 

third_party/blink/web_tests/external/wpt/.well-known/origin-policy

@@ -35,6 +35,6 @@ def main(request, response):
     if len(matches) != 1:
         return 404, [], '{} origin policies found at a path matching "{}"'.format(len(matches), filepath_pattern)
 
-    with open(matches[0]) as f:
+    with open(matches[0], 'rb') as f:
         data = f.read()
         return return_code, [('Content-Type', content_type)], data

third_party/blink/web_tests/external/wpt/cookies/resources/cookie.py

@@ -21,7 +21,7 @@ def main(request, response):
     try:
         if b'drop' in request.GET:
             cookie = request.GET[b'drop']
-            cookie += "; max-age=0"
+            cookie += b'; max-age=0'
 
         if b'set' in request.GET:
             cookie = request.GET[b'set']

third_party/blink/web_tests/external/wpt/fetch/metadata/resources/post-to-owner.py

@@ -9,6 +9,10 @@ def main(request, response):
     ]
     key = request.GET.first(b"key", None)
 
+    # We serialize the key into JSON, so have to decode it first.
+    if key is not None:
+      key = key.decode('utf-8')
+
     body = u"""
         <!DOCTYPE html>
         <script src="/portals/resources/stash-utils.sub.js"></script>

third_party/blink/web_tests/external/wpt/service-workers/service-worker/worker-interception.https-expected.txt

@@ -8,9 +8,9 @@ PASS Verify a cors worker script served by a service worker fails shared worker
 PASS Verify a no-cors cross-origin worker script served by a service worker fails dedicated worker start.
 PASS Verify a no-cors cross-origin worker script served by a service worker fails shared worker start.
 PASS Register a service worker for worker subresource interception tests.
-FAIL Requests on a dedicated worker controlled by a service worker. assert_equals: expected "This load was successfully intercepted." but got "{\"error\": {\"message\": \"\", \"code\": 404}}"
+FAIL Requests on a dedicated worker controlled by a service worker. assert_equals: expected "This load was successfully intercepted." but got "{\"error\": {\"code\": 404, \"message\": \"\"}}"
 PASS Requests on a shared worker controlled by a service worker.
-FAIL Requests on a dedicated worker nested in a dedicated worker and controlled by a service worker assert_equals: expected "This load was successfully intercepted." but got "{\"error\": {\"message\": \"\", \"code\": 404}}"
+FAIL Requests on a dedicated worker nested in a dedicated worker and controlled by a service worker assert_equals: expected "This load was successfully intercepted." but got "{\"error\": {\"code\": 404, \"message\": \"\"}}"
 FAIL Requests on a dedicated worker nested in a shared worker and controlled by a service worker assert_equals: expected "This load was successfully intercepted." but got "Unexpected error! Worker is not defined"
 PASS Unregister a service worker for subresource interception tests.
 Harness: the test ran to completion.

third_party/blink/web_tests/external/wpt/worklets/idlharness.worker-expected.txt

 This is a testharness.js-based test.
 FAIL worklets interfaces promise_test: Unhandled rejection with value: object "WebIDLParseError: Syntax error at line 1:
-{"error": {"message"
+{"error": {"code"
 ^ Unrecognised tokens"
 Harness: the test ran to completion.
 

third_party/blink/web_tests/external/wpt/xhr/resources/auth5/auth.py

@@ -10,6 +10,6 @@ def main(request, response):
         response.headers.set(b'WWW-Authenticate', b'Basic realm="test"')
         content = b'User name/password wrong or not given: '
 
-    content += b"%s\n%s" % (request.auth.username,
-                            request.auth.password)
+    content += b"%s\n%s" % (request.auth.username or b'',
+                            request.auth.password or b'')
     return content

third_party/blink/web_tests/wpt_internal/origin-isolation/resources/send-headers.py

@@ -10,17 +10,17 @@ def main(request, response):
 
     token = "ArQvBL/jhDJ62HaUm/ak0dIUYDjZAfeCQTXwa92cOrHZbL7R+bhb3qrVO2pHWkgJPgvIzvLX5m3wfaUJfOKY0Q4AAABqeyJvcmlnaW4iOiAiaHR0cHM6Ly93d3cud2ViLXBsYXRmb3JtLnRlc3Q6ODQ0NCIsICJmZWF0dXJlIjogIk9yaWdpbklzb2xhdGlvbkhlYWRlciIsICJleHBpcnkiOiAyMDAwMDAwMDAwfQ=="
 
-    header_order = request.GET.first("headerOrder")
-    if header_order == "otoi":
-        response.headers.set("Origin-Trial", token)
-        response.headers.set("Origin-Isolation", "?1")
-    elif header_order == "oiot":
-        response.headers.set("Origin-Isolation", "?1")
-        response.headers.set("Origin-Trial", token)
+    header_order = request.GET.first(b"headerOrder")
+    if header_order == b"otoi":
+        response.headers.set(b"Origin-Trial", token)
+        response.headers.set(b"Origin-Isolation", b"?1")
+    elif header_order == b"oiot":
+        response.headers.set(b"Origin-Isolation", b"?1")
+        response.headers.set(b"Origin-Trial", token)
     else:
         raise AssertionError("Invalid headerOrder")
 
-    response.headers.set("Content-Type", "text/html")
+    response.headers.set(b"Content-Type", b"text/html")
 
     return """
     <!DOCTYPE html>

third_party/blink/web_tests/wpt_internal/portals/resources/report.py

@@ -3,11 +3,11 @@ import json
 
 
 def main(request, response):
-    op = request.GET.first("op")
-    id = request.GET.first("id")
+    op = request.GET.first(b"op")
+    id = request.GET.first(b"id")
     timeout = 1.0
 
-    if op == "retrieve":
+    if op == b"retrieve":
         t0 = time.time()
         while time.time() - t0 < timeout:
             time.sleep(0.1)
@@ -23,4 +23,4 @@ def main(request, response):
         request.server.stash.put(key=id, value=json.dumps({'url': request.url}))
 
     # return acknowledgement report
-    return [("Content-Type", "text/plain")], "Recorded report " + id
+    return [("Content-Type", "text/plain")], b"Recorded report " + id