test: fix Python unittests

.travis.yml

@@ -84,7 +84,7 @@ matrix:
 
 install:
   #- pip install -r requirements.txt
-  - pip install flake8  # pytest  # add another testing frameworks later
+  - pip install --upgrade flake8 pytest==4.6.6  # pytest 5 no longer supports legacy Python
 before_script:
   - flake8 --version
   # stop the build if there are Python syntax errors or undefined names
@@ -96,7 +96,7 @@ before_script:
 script:
   - node -e 'require("npmlog").level="verbose"; require("./lib/find-python")(null,()=>{})'
   - npm test
-  #- pytest --capture=sys  # add other tests here
+  - pytest
 notifications:
   on_success: change
   on_failure: change  # `always` will be the setting once code changes slow down

gyp/gyp_main.py

@@ -31,7 +31,7 @@ def UnixifyPath(path):
     out = subprocess.Popen(["cygpath", "-u", path],
             stdout=subprocess.PIPE,
             stderr=subprocess.STDOUT)
-    stdout, stderr = out.communicate()
+    stdout, _ = out.communicate()
     if PY3:
       stdout = stdout.decode("utf-8")
     return str(stdout)

gyp/pylib/gyp/MSVSSettings_test.py

@@ -1085,6 +1085,7 @@ def testConvertToMSBuildSettings_full_synthetic(self):
             'GenerateManifest': 'true',
             'IgnoreImportLibrary': 'true',
             'LinkIncremental': 'false'}}
+    self.maxDiff = 9999  # on failure display a long diff
     actual_msbuild_settings = MSVSSettings.ConvertToMSBuildSettings(
         msvs_settings,
         self.stderr)
@@ -1476,6 +1477,7 @@ def testConvertToMSBuildSettings_actual(self):
             'ResourceOutputFileName':
             '$(IntDir)$(TargetFileName).embed.manifest.resfdsf'}
         }
+    self.maxDiff = 9999  # on failure display a long diff
     actual_msbuild_settings = MSVSSettings.ConvertToMSBuildSettings(
         msvs_settings,
         self.stderr)

gyp/pylib/gyp/common.py

@@ -2,7 +2,6 @@
 # Use of this source code is governed by a BSD-style license that can be
 # found in the LICENSE file.
 
-import collections
 import errno
 import filecmp
 import os.path
@@ -11,6 +10,11 @@
 import sys
 import subprocess
 
+try:
+  from collections.abc import MutableSet
+except ImportError:
+  from collections import MutableSet
+
 PY3 = bytes != str
 
 
@@ -496,7 +500,7 @@ def uniquer(seq, idfun=None):
 
 
 # Based on http://code.activestate.com/recipes/576694/.
-class OrderedSet(collections.MutableSet):
+class OrderedSet(MutableSet):
   def __init__(self, iterable=None):
     self.end = end = []
     end += [None, end, end]         # sentinel node for doubly linked list

gyp/pylib/gyp/generator/msvs.py

@@ -12,6 +12,8 @@
 import subprocess
 import sys
 
+from collections import OrderedDict
+
 import gyp.common
 import gyp.easy_xml as easy_xml
 import gyp.generator.ninja as ninja_generator
@@ -27,16 +29,6 @@
 
 PY3 = bytes != str
 
-# TODO: Remove once bots are on 2.7, http://crbug.com/241769
-def _import_OrderedDict():
-  import collections
-  try:
-    return collections.OrderedDict
-  except AttributeError:
-    import gyp.ordered_dict
-    return gyp.ordered_dict.OrderedDict
-OrderedDict = _import_OrderedDict()
-
 
 # Regular expression for validating Visual Studio GUIDs.  If the GUID
 # contains lowercase hex letters, MSVS will be fine. However,
@@ -179,7 +171,7 @@ def _FixPath(path):
 
 
 def _IsWindowsAbsPath(path):
-  """
+  r"""
   On Cygwin systems Python needs a little help determining if a path is an absolute Windows path or not, so that
   it does not treat those as relative, which results in bad paths like:
 

gyp/pylib/gyp/generator/ninja_test.py

@@ -9,7 +9,6 @@
 import gyp.generator.ninja as ninja
 import unittest
 import sys
-import TestCommon
 
 
 class TestPrefixesAndSuffixes(unittest.TestCase):