Upgrade pylint (#2917)

depot_tools is removing pylint from its distribution so we must maintain
our own copy.

tools/setup_test.py

@@ -1,27 +1,25 @@
 # Copyright 2018-2019 the Deno authors. All rights reserved. MIT license.
 import os
 import sys
-
-from setup import gn_string, read_gn_args, write_gn_args
 from shutil import rmtree
 from tempfile import mktemp
-
+from setup import gn_string, read_gn_args, write_gn_args
 from test_util import DenoTestCase, run_tests
 
 
 class TestSetup(DenoTestCase):
     def test_gn_string(self):
-        assert '"abc"' == gn_string('abc')
-        assert '"foo\\$bar\\"baz"' == gn_string('foo$bar"baz')
-        assert '"do\\not\\escape"' == gn_string('do\\not\\escape')
-        assert '"so\\\\\\very\\\\\\"fun\\"' == gn_string('so\\\\very\\"fun\\')
+        assert gn_string('abc') == '"abc"'
+        assert gn_string('foo$bar"baz') == '"foo\\$bar\\"baz"'
+        assert gn_string('do\\not\\escape') == '"do\\not\\escape"'
+        assert gn_string('so\\\\very\\"fun\\') == '"so\\\\\\very\\\\\\"fun\\"'
 
     def test_read_gn_args(self):
         # Args file doesn't exist.
         (args,
          hand_edited) = read_gn_args("/baddir/hopefully/nonexistent/args.gn")
         assert args is None
-        assert hand_edited == False
+        assert not hand_edited
 
         # Handwritten empty args file.
         filename = mktemp()
@@ -30,7 +28,7 @@ class TestSetup(DenoTestCase):
         (args, hand_edited) = read_gn_args(filename)
         os.remove(filename)
         assert args == []
-        assert hand_edited == True
+        assert hand_edited
 
         # Handwritten non-empty args file.
         expect_args = ['some_number=2', 'another_string="ran/dom#yes"']
@@ -40,7 +38,7 @@ class TestSetup(DenoTestCase):
         (args, hand_edited) = read_gn_args(filename)
         os.remove(filename)
         assert args == expect_args
-        assert hand_edited == True
+        assert hand_edited
 
     def test_write_gn_args(self):
         # Build a nonexistent path; write_gn_args() should call mkdir as needed.
@@ -57,7 +55,7 @@ class TestSetup(DenoTestCase):
         # Validate that the right contents were written.
         (check_args, hand_edited) = read_gn_args(filename)
         assert check_args == args
-        assert hand_edited == False
+        assert not hand_edited
         # Clean up.
         rmtree(d)