Merge branch 'master' into topic/grossag/pythonscanner

45 files changed, 179 insertions, 315 deletions

diff --git a/src/engine/SCons/BuilderTests.py b/src/engine/SCons/BuilderTests.py
index b03a425..f28e201 100644
--- a/src/engine/SCons/BuilderTests.py
+++ b/src/engine/SCons/BuilderTests.py
@@ -581,7 +581,7 @@ class BuilderTestCase(unittest.TestCase):
         assert b5.src_suffixes(env) == ['.y'], b5.src_suffixes(env)
 
     def test_srcsuffix_nonext(self):
-        "Test target generation from non-extension source suffixes"
+        """Test target generation from non-extension source suffixes"""
         env = Environment()
         b6 = SCons.Builder.Builder(action = '',
                                    src_suffix='_src.a',
@@ -679,7 +679,7 @@ class BuilderTestCase(unittest.TestCase):
             """create the file"""
             with open(str(target[0]), "w"):
                 pass
-            if (len(source) == 1 and len(target) == 1):
+            if len(source) == 1 and len(target) == 1:
                 env['CNT'][0] = env['CNT'][0] + 1
 
         env = Environment()
diff --git a/src/engine/SCons/CacheDirTests.py b/src/engine/SCons/CacheDirTests.py
index 07c32b4..0e242c4 100644
--- a/src/engine/SCons/CacheDirTests.py
+++ b/src/engine/SCons/CacheDirTests.py
@@ -130,7 +130,7 @@ class ExceptionTestCase(unittest.TestCase):
     @unittest.skipIf(sys.platform.startswith("win"), "This fixture will not trigger an OSError on Windows")
     def test_throws_correct_on_OSError(self):
         """Test that the correct error is thrown when cache directory cannot be created."""
-        privileged_dir = os.path.join(os.getcwd(), "privileged")
+        privileged_dir = os.path.join(self.tmpdir, "privileged")
         try:
             os.mkdir(privileged_dir)
             os.chmod(privileged_dir, stat.S_IREAD)
diff --git a/src/engine/SCons/Environment.py b/src/engine/SCons/Environment.py
index 27179c3..19e7bd1 100644
--- a/src/engine/SCons/Environment.py
+++ b/src/engine/SCons/Environment.py
@@ -2199,16 +2199,6 @@ class Base(SubstitutionEnvironment):
                 target.side_effects.append(side_effect)
         return side_effects
 
-    def SourceCode(self, entry, builder):
-        """Arrange for a source code builder for (part of) a tree."""
-        msg = """SourceCode() has been deprecated and there is no replacement.
-\tIf you need this function, please contact scons-dev@scons.org"""
-        SCons.Warnings.warn(SCons.Warnings.DeprecatedSourceCodeWarning, msg)
-        entries = self.arg2nodes(entry, self.fs.Entry)
-        for entry in entries:
-            entry.set_src_builder(builder)
-        return entries
-
     def Split(self, arg):
         """This function converts a string or list into a list of strings
         or Nodes.  This makes things easier for users by allowing files to
@@ -2257,7 +2247,7 @@ class Base(SubstitutionEnvironment):
         build_source(node.all_children())
 
         def final_source(node):
-            while (node != node.srcnode()):
+            while node != node.srcnode():
               node = node.srcnode()
             return node
         sources = list(map(final_source, sources))
diff --git a/src/engine/SCons/Environment.xml b/src/engine/SCons/Environment.xml
index 6f263a4..b1c2039 100644
--- a/src/engine/SCons/Environment.xml
+++ b/src/engine/SCons/Environment.xml
@@ -2879,137 +2879,6 @@ function.
 </summary>
 </scons_function>
 
-<scons_function name="SourceCode">
-<arguments>
-(entries, builder)
-</arguments>
-<summary>
-<para>
-This function and its associate factory functions are deprecated.
-There is no replacement.
-The intended use was to keep a local tree in sync with an archive,
-but in actuality the function only causes the archive
-to be fetched on the first run.
-Synchronizing with the archive is best done external to &SCons;.
-</para>
-
-<para>
-Arrange for non-existent source files to
-be fetched from a source code management system
-using the specified
-<varname>builder</varname>.
-The specified
-<varname>entries</varname>
-may be a Node, string or list of both,
-and may represent either individual
-source files or directories in which
-source files can be found.
-</para>
-
-<para>
-For any non-existent source files,
-&scons;
-will search up the directory tree
-and use the first
-&f-SourceCode;
-builder it finds.
-The specified
-<varname>builder</varname>
-may be
-<literal>None</literal>,
-in which case
-&scons;
-will not use a builder to fetch
-source files for the specified
-<varname>entries</varname>,
-even if a
-&f-SourceCode;
-builder has been specified
-for a directory higher up the tree.
-</para>
-
-<para>
-&scons;
-will, by default,
-fetch files from SCCS or RCS subdirectories
-without explicit configuration.
-This takes some extra processing time
-to search for the necessary
-source code management files on disk.
-You can avoid these extra searches
-and speed up your build a little
-by disabling these searches as follows:
-</para>
-
-<example_commands>
-env.SourceCode('.', None)
-</example_commands>
-
-<para>
-Note that if the specified
-<varname>builder</varname>
-is one you create by hand,
-it must have an associated
-construction environment to use
-when fetching a source file.
-</para>
-
-<para>
-&scons;
-provides a set of canned factory
-functions that return appropriate
-Builders for various popular
-source code management systems.
-Canonical examples of invocation include:
-</para>
-
-<example_commands>
-env.SourceCode('.', env.BitKeeper('/usr/local/BKsources'))
-env.SourceCode('src', env.CVS('/usr/local/CVSROOT'))
-env.SourceCode('/', env.RCS())
-env.SourceCode(['f1.c', 'f2.c'], env.SCCS())
-env.SourceCode('no_source.c', None)
-</example_commands>
-<para>
-<!-- env.SourceCode('.', env.Subversion('file:///usr/local/Subversion')) -->
-</para>
-</summary>
-</scons_function>
-
-<scons_function name="Split">
-<arguments>
-(arg)
-</arguments>
-<summary>
-<para>
-Returns a list of file names or other objects.
-If arg is a string,
-it will be split on strings of white-space characters
-within the string,
-making it easier to write long lists of file names.
-If arg is already a list,
-the list will be returned untouched.
-If arg is any other type of object,
-it will be returned as a list
-containing just the object.
-</para>
-
-<para>
-Example:
-</para>
-
-<example_commands>
-files = Split("f1.c f2.c f3.c")
-files = env.Split("f4.c f5.c f6.c")
-files = Split("""
-	f7.c
-	f8.c
-	f9.c
-""")
-</example_commands>
-</summary>
-</scons_function>
-
 <scons_function name="subst">
 <arguments signature="env">
 (input, [raw, target, source, conv])
diff --git a/src/engine/SCons/EnvironmentTests.py b/src/engine/SCons/EnvironmentTests.py
index b2f2bd5..0e71f9e 100644
--- a/src/engine/SCons/EnvironmentTests.py
+++ b/src/engine/SCons/EnvironmentTests.py
@@ -726,7 +726,7 @@ sys.exit(0)
         assert r == 'replace_func2', r
 
     def test_Override(self):
-        "Test overriding construction variables"
+        """Test overriding construction variables"""
         env = SubstitutionEnvironment(ONE=1, TWO=2, THREE=3, FOUR=4)
         assert env['ONE'] == 1, env['ONE']
         assert env['TWO'] == 2, env['TWO']
@@ -1408,7 +1408,7 @@ def exists(env):
         assert env['XYZ'] == 'ddd', env
 
     def test_concat(self):
-        "Test _concat()"
+        """Test _concat()"""
         e1 = self.TestEnvironment(PRE='pre', SUF='suf', STR='a b', LIST=['a', 'b'])
         s = e1.subst
         x = s("${_concat('', '', '', __env__)}")
@@ -1423,7 +1423,7 @@ def exists(env):
         assert x == 'preasuf prebsuf', x
 
     def test_concat_nested(self):
-        "Test _concat() on a nested substitution strings."
+        """Test _concat() on a nested substitution strings."""
         e = self.TestEnvironment(PRE='pre', SUF='suf',
                                  L1=['a', 'b'],
                                  L2=['c', 'd'],
@@ -1956,7 +1956,7 @@ def generate(env):
         assert 'XXX' not in env.Dictionary()
 
     def test_FindIxes(self):
-        "Test FindIxes()"
+        """Test FindIxes()"""
         env = self.TestEnvironment(LIBPREFIX='lib',
                           LIBSUFFIX='.a',
                           SHLIBPREFIX='lib',
@@ -2398,7 +2398,7 @@ f5: \
         assert hasattr(env3, 'b2'), "b2 was not set"
 
     def test_ReplaceIxes(self):
-        "Test ReplaceIxes()"
+        """Test ReplaceIxes()"""
         env = self.TestEnvironment(LIBPREFIX='lib',
                           LIBSUFFIX='.a',
                           SHLIBPREFIX='lib',
@@ -3255,25 +3255,6 @@ def generate(env):
         assert ggg.side_effects == [s], ggg.side_effects
         assert ccc.side_effects == [s], ccc.side_effects
 
-    def test_SourceCode(self):
-        """Test the SourceCode() method."""
-        env = self.TestEnvironment(FOO='mmm', BAR='nnn')
-        e = env.SourceCode('foo', None)[0]
-        assert e.get_internal_path() == 'foo'
-        s = e.src_builder()
-        assert s is None, s
-
-        b = Builder()
-        e = env.SourceCode(e, b)[0]
-        assert e.get_internal_path() == 'foo'
-        s = e.src_builder()
-        assert s is b, s
-
-        e = env.SourceCode('$BAR$FOO', None)[0]
-        assert e.get_internal_path() == 'nnnmmm'
-        s = e.src_builder()
-        assert s is None, s
-
     def test_Split(self):
         """Test the Split() method"""
         env = self.TestEnvironment(FOO = 'fff', BAR = 'bbb')
@@ -3450,7 +3431,7 @@ def generate(env):
             assert x in over, bad_msg % x
 
     def test_parse_flags(self):
-        '''Test the Base class parse_flags argument'''
+        """Test the Base class parse_flags argument"""
         # all we have to show is that it gets to MergeFlags internally
         env = Environment(tools=[], parse_flags = '-X')
         assert env['CCFLAGS'] == ['-X'], env['CCFLAGS']
@@ -3464,7 +3445,7 @@ def generate(env):
         assert env['CPPDEFINES'] == ['FOO', 'BAR'], env['CPPDEFINES']
 
     def test_clone_parse_flags(self):
-        '''Test the env.Clone() parse_flags argument'''
+        """Test the env.Clone() parse_flags argument"""
         # all we have to show is that it gets to MergeFlags internally
         env = Environment(tools = [])
         env2 = env.Clone(parse_flags = '-X')
@@ -3733,7 +3714,7 @@ class OverrideEnvironmentTestCase(unittest.TestCase,TestEnvironmentFixture):
         assert x == ['x3', 'y3', 'z3'], x
 
     def test_parse_flags(self):
-        '''Test the OverrideEnvironment parse_flags argument'''
+        """Test the OverrideEnvironment parse_flags argument"""
         # all we have to show is that it gets to MergeFlags internally
         env = SubstitutionEnvironment()
         env2 = env.Override({'parse_flags' : '-X'})
diff --git a/src/engine/SCons/EnvironmentValues.py b/src/engine/SCons/EnvironmentValues.py
index d94bf3a..6599196 100644
--- a/src/engine/SCons/EnvironmentValues.py
+++ b/src/engine/SCons/EnvironmentValues.py
@@ -3,7 +3,7 @@ import re
 _is_valid_var = re.compile(r'[_a-zA-Z]\w*$')
 
 _rm = re.compile(r'\$[()]')
-_remove = re.compile(r'\$\([^\$]*(\$[^\)][^\$]*)*\$\)')
+_remove = re.compile(r'\$\([^$]*(\$[^)][^$]*)*\$\)')
 
 # Regular expressions for splitting strings and handling substitutions,
 # for use by the scons_subst() and scons_subst_list() functions:
@@ -28,7 +28,7 @@ _remove = re.compile(r'\$\([^\$]*(\$[^\)][^\$]*)*\$\)')
 #
 _dollar_exps_str = r'\$[\$\(\)]|\$[_a-zA-Z][\.\w]*|\${[^}]*}'
 _dollar_exps = re.compile(r'(%s)' % _dollar_exps_str)
-_separate_args = re.compile(r'(%s|\s+|[^\s\$]+|\$)' % _dollar_exps_str)
+_separate_args = re.compile(r'(%s|\s+|[^\s$]+|\$)' % _dollar_exps_str)
 
 # This regular expression is used to replace strings of multiple white
 # space characters in the string result from the scons_subst() function.
diff --git a/src/engine/SCons/JobTests.py b/src/engine/SCons/JobTests.py
index 26e3d37..2e3af4f 100644
--- a/src/engine/SCons/JobTests.py
+++ b/src/engine/SCons/JobTests.py
@@ -46,7 +46,7 @@ def get_cpu_nums():
             return int( os.popen2( "sysctl -n hw.ncpu")[1].read() )
     # Windows:
     if "NUMBER_OF_PROCESSORS" in os.environ:
-        ncpus = int( os.environ[ "NUMBER_OF_PROCESSORS" ] );
+        ncpus = int(os.environ["NUMBER_OF_PROCESSORS"])
     if ncpus > 0:
         return ncpus
     return 1 # Default
@@ -59,14 +59,14 @@ num_jobs = get_cpu_nums()*2
 
 # in case we werent able to detect num cpus for this test
 # just make a hardcoded suffcient large number, though not future proof
-if(num_jobs == 2):
+if num_jobs == 2:
     num_jobs = 33
 
 # how many tasks to perform for the test
 num_tasks = num_jobs*5
 
 class DummyLock(object):
-    "fake lock class to use if threads are not supported"
+    """fake lock class to use if threads are not supported"""
     def acquire(self):
         pass
 
@@ -74,7 +74,7 @@ class DummyLock(object):
         pass
 
 class NoThreadsException(Exception):
-    "raised by the ParallelTestCase if threads are not supported"
+    """raised by the ParallelTestCase if threads are not supported"""
 
     def __str__(self):
         return "the interpreter doesn't support threads"
@@ -113,7 +113,7 @@ class Task(object):
 
         # check if task was executing while another was also executing
         for j in range(1, self.taskmaster.num_tasks):
-            if(self.taskmaster.parallel_list[j+1] == 1):
+            if self.taskmaster.parallel_list[j + 1] == 1:
                 self.taskmaster.found_parallel = True
                 break
 
@@ -237,7 +237,7 @@ class Taskmaster(object):
         return self.num_postprocessed == self.num_tasks
 
     def tasks_were_serial(self):
-        "analyze the task order to see if they were serial"
+        """analyze the task order to see if they were serial"""
         return not self.found_parallel
 
     def exception_set(self):
@@ -251,7 +251,7 @@ ThreadPoolCallList = []
 
 class ParallelTestCase(unittest.TestCase):
     def runTest(self):
-        "test parallel jobs"
+        """test parallel jobs"""
 
         try:
             import threading
@@ -319,7 +319,7 @@ class ParallelTestCase(unittest.TestCase):
 
 class SerialTestCase(unittest.TestCase):
     def runTest(self):
-        "test a serial job"
+        """test a serial job"""
 
         taskmaster = Taskmaster(num_tasks, self, RandomTask)
         jobs = SCons.Job.Jobs(1, taskmaster)
@@ -338,7 +338,7 @@ class SerialTestCase(unittest.TestCase):
 
 class NoParallelTestCase(unittest.TestCase):
     def runTest(self):
-        "test handling lack of parallel support"
+        """test handling lack of parallel support"""
         def NoParallel(tm, num, stack_size):
             raise NameError
         save_Parallel = SCons.Job.Parallel
@@ -365,7 +365,7 @@ class NoParallelTestCase(unittest.TestCase):
 
 class SerialExceptionTestCase(unittest.TestCase):
     def runTest(self):
-        "test a serial job with tasks that raise exceptions"
+        """test a serial job with tasks that raise exceptions"""
 
         taskmaster = Taskmaster(num_tasks, self, ExceptionTask)
         jobs = SCons.Job.Jobs(1, taskmaster)
@@ -382,7 +382,7 @@ class SerialExceptionTestCase(unittest.TestCase):
 
 class ParallelExceptionTestCase(unittest.TestCase):
     def runTest(self):
-        "test parallel jobs with tasks that raise exceptions"
+        """test parallel jobs with tasks that raise exceptions"""
 
         taskmaster = Taskmaster(num_tasks, self, ExceptionTask)
         jobs = SCons.Job.Jobs(num_jobs, taskmaster)
@@ -534,13 +534,13 @@ class _SConsTaskTest(unittest.TestCase):
 
 class SerialTaskTest(_SConsTaskTest):
     def runTest(self):
-        "test serial jobs with actual Taskmaster and Task"
+        """test serial jobs with actual Taskmaster and Task"""
         self._test_seq(1)
 
 
 class ParallelTaskTest(_SConsTaskTest):
     def runTest(self):
-        "test parallel jobs with actual Taskmaster and Task"
+        """test parallel jobs with actual Taskmaster and Task"""
         self._test_seq(num_jobs)
 
 
diff --git a/src/engine/SCons/Node/Alias.py b/src/engine/SCons/Node/Alias.py
index a035816..55d94f9 100644
--- a/src/engine/SCons/Node/Alias.py
+++ b/src/engine/SCons/Node/Alias.py
@@ -37,6 +37,7 @@ import collections
 import SCons.Errors
 import SCons.Node
 import SCons.Util
+from SCons.Util import MD5signature
 
 class AliasNameSpace(collections.UserDict):
     def Alias(self, name, **kw):
@@ -166,7 +167,7 @@ class Alias(SCons.Node.Node):
             pass
 
         contents = self.get_contents()
-        csig = SCons.Util.MD5signature(contents)
+        csig = MD5signature(contents)
         self.get_ninfo().csig = csig
         return csig
 
diff --git a/src/engine/SCons/Node/FS.py b/src/engine/SCons/Node/FS.py
index 4c68358..e1d6f68 100644
--- a/src/engine/SCons/Node/FS.py
+++ b/src/engine/SCons/Node/FS.py
@@ -54,6 +54,7 @@ import SCons.Node
 import SCons.Node.Alias
 import SCons.Subst
 import SCons.Util
+from SCons.Util import MD5signature, MD5filesignature, MD5collect
 import SCons.Warnings
 
 from SCons.Debug import Trace
@@ -1862,7 +1863,7 @@ class Dir(Base):
         node is called which has a child directory, the child
         directory should return the hash of its contents."""
         contents = self.get_contents()
-        return SCons.Util.MD5signature(contents)
+        return MD5signature(contents)
 
     def do_duplicate(self, src):
         pass
@@ -2501,14 +2502,14 @@ class FileBuildInfo(SCons.Node.BuildInfoBase):
 
     Attributes unique to FileBuildInfo:
         dependency_map : Caches file->csig mapping
-                    for all dependencies.  Currently this is only used when using
-                    MD5-timestamp decider.
-                    It's used to ensure that we copy the correct
-                    csig from previous build to be written to .sconsign when current build
-                    is done. Previously the matching of csig to file was strictly by order
-                    they appeared in bdepends, bsources, or bimplicit, and so a change in order
-                    or count of any of these could yield writing wrong csig, and then false positive
-                    rebuilds
+            for all dependencies.  Currently this is only used when using
+            MD5-timestamp decider.
+            It's used to ensure that we copy the correct csig from the
+            previous build to be written to .sconsign when current build
+            is done. Previously the matching of csig to file was strictly
+            by order they appeared in bdepends, bsources, or bimplicit,
+            and so a change in order or count of any of these could
+            yield writing wrong csig, and then false positive rebuilds
     """
     __slots__ = ['dependency_map', ]
     current_version_id = 2
@@ -2723,11 +2724,10 @@ class File(Base):
         Compute and return the MD5 hash for this file.
         """
         if not self.rexists():
-            return SCons.Util.MD5signature('')
+            return MD5signature('')
         fname = self.rfile().get_abspath()
         try:
-            cs = SCons.Util.MD5filesignature(fname,
-                chunksize=SCons.Node.FS.File.md5_chunksize*1024)
+            cs = MD5filesignature(fname, chunksize=File.md5_chunksize * 1024)
         except EnvironmentError as e:
             if not e.filename:
                 e.filename = fname
@@ -3028,7 +3028,7 @@ class File(Base):
 
          @see: built() and Node.release_target_info()
          """
-        if (self.released_target_info or SCons.Node.interactive):
+        if self.released_target_info or SCons.Node.interactive:
             return
 
         if not hasattr(self.attributes, 'keep_targetinfo'):
@@ -3210,7 +3210,7 @@ class File(Base):
         if csig is None:
 
             try:
-                if self.get_size() < SCons.Node.FS.File.md5_chunksize:
+                if self.get_size() < File.md5_chunksize:
                     contents = self.get_contents()
                 else:
                     csig = self.get_content_hash()
@@ -3312,7 +3312,7 @@ class File(Base):
 
         # For an "empty" binfo properties like bsources
         # do not exist: check this to avoid exception.
-        if (len(binfo.bsourcesigs) + len(binfo.bdependsigs) + \
+        if (len(binfo.bsourcesigs) + len(binfo.bdependsigs) +
             len(binfo.bimplicitsigs)) == 0:
             return {}
 
@@ -3580,7 +3580,7 @@ class File(Base):
                 node = repo_dir.file_on_disk(self.name)
 
             if node and node.exists() and \
-                    (isinstance(node, File) or isinstance(node, Entry) \
+                    (isinstance(node, File) or isinstance(node, Entry)
                      or not node.is_derived()):
                 retvals.append(node)
 
@@ -3611,8 +3611,7 @@ class File(Base):
 
         cachedir, cachefile = self.get_build_env().get_CacheDir().cachepath(self)
         if not self.exists() and cachefile and os.path.exists(cachefile):
-            self.cachedir_csig = SCons.Util.MD5filesignature(cachefile, \
-                SCons.Node.FS.File.md5_chunksize * 1024)
+            self.cachedir_csig = MD5filesignature(cachefile, File.md5_chunksize * 1024)
         else:
             self.cachedir_csig = self.get_csig()
         return self.cachedir_csig
@@ -3632,7 +3631,7 @@ class File(Base):
 
         executor = self.get_executor()
 
-        result = self.contentsig = SCons.Util.MD5signature(executor.get_contents())
+        result = self.contentsig = MD5signature(executor.get_contents())
         return result
 
     def get_cachedir_bsig(self):
@@ -3663,7 +3662,7 @@ class File(Base):
         sigs.append(self.get_internal_path())
 
         # Merge this all into a single signature
-        result = self.cachesig = SCons.Util.MD5collect(sigs)
+        result = self.cachesig = MD5collect(sigs)
         return result
 
 default_fs = None
diff --git a/src/engine/SCons/Node/FSTests.py b/src/engine/SCons/Node/FSTests.py
index eddfdf0..9c19481 100644
--- a/src/engine/SCons/Node/FSTests.py
+++ b/src/engine/SCons/Node/FSTests.py
@@ -2508,8 +2508,8 @@ class FileTestCase(_tempdirTestCase):
         build_f1, src_f1)
 
     def test_changed(self):
-        """ 
-        Verify that changes between BuildInfo's list of souces, depends, and implicit 
+        """
+        Verify that changes between BuildInfo's list of souces, depends, and implicit
         dependencies do not corrupt content signature values written to .SConsign
         when using CacheDir and Timestamp-MD5 decider.
         This is for issue #2980
@@ -3374,10 +3374,11 @@ class find_fileTestCase(unittest.TestCase):
         node_pseudo.set_src_builder(1)  # Any non-zero value.
 
         paths = tuple(map(fs.Dir, ['.', 'same', './bar']))
-        nodes = [SCons.Node.FS.find_file('foo', paths)]
-        nodes.append(SCons.Node.FS.find_file('baz', paths))
-        nodes.append(SCons.Node.FS.find_file('pseudo', paths))
-        nodes.append(SCons.Node.FS.find_file('same', paths))
+        nodes = [SCons.Node.FS.find_file('foo', paths),
+                 SCons.Node.FS.find_file('baz', paths),
+                 SCons.Node.FS.find_file('pseudo', paths),
+                 SCons.Node.FS.find_file('same', paths)
+        ]
 
         file_names = list(map(str, nodes))
         file_names = list(map(os.path.normpath, file_names))
diff --git a/src/engine/SCons/Node/NodeTests.py b/src/engine/SCons/Node/NodeTests.py
index 678e03e..d8179ff 100644
--- a/src/engine/SCons/Node/NodeTests.py
+++ b/src/engine/SCons/Node/NodeTests.py
@@ -1304,7 +1304,7 @@ class NodeTestCase(unittest.TestCase):
     def test_postprocess(self):
         """Test calling the base Node postprocess() method"""
         n = SCons.Node.Node()
-        n.waiting_parents = set( ['foo','bar'] )
+        n.waiting_parents = {'foo', 'bar'}
 
         n.postprocess()
         assert n.waiting_parents == set(), n.waiting_parents
@@ -1316,7 +1316,7 @@ class NodeTestCase(unittest.TestCase):
         assert n1.waiting_parents == set(), n1.waiting_parents
         r = n1.add_to_waiting_parents(n2)
         assert r == 1, r
-        assert n1.waiting_parents == set((n2,)), n1.waiting_parents
+        assert n1.waiting_parents == {n2}, n1.waiting_parents
         r = n1.add_to_waiting_parents(n2)
         assert r == 0, r
 
diff --git a/src/engine/SCons/Node/__init__.py b/src/engine/SCons/Node/__init__.py
index daf79ba..0b58282 100644
--- a/src/engine/SCons/Node/__init__.py
+++ b/src/engine/SCons/Node/__init__.py
@@ -60,6 +60,7 @@ from SCons.Debug import logInstanceCreation
 import SCons.Executor
 import SCons.Memoize
 import SCons.Util
+from SCons.Util import MD5signature
 
 from SCons.Debug import Trace
 
@@ -1167,7 +1168,7 @@ class Node(object, with_metaclass(NoSlotsPyPy)):
 
         if self.has_builder():
             binfo.bact = str(executor)
-            binfo.bactsig = SCons.Util.MD5signature(executor.get_contents())
+            binfo.bactsig = MD5signature(executor.get_contents())
 
         if self._specific_sources:
             sources = [s for s in self.sources if s not in ignore_set]
@@ -1205,7 +1206,7 @@ class Node(object, with_metaclass(NoSlotsPyPy)):
             return self.ninfo.csig
         except AttributeError:
             ninfo = self.get_ninfo()
-            ninfo.csig = SCons.Util.MD5signature(self.get_contents())
+            ninfo.csig = MD5signature(self.get_contents())
             return self.ninfo.csig
 
     def get_cachedir_csig(self):
@@ -1496,7 +1497,7 @@ class Node(object, with_metaclass(NoSlotsPyPy)):
 
         if self.has_builder():
             contents = self.get_executor().get_contents()
-            newsig = SCons.Util.MD5signature(contents)
+            newsig = MD5signature(contents)
             if bi.bactsig != newsig:
                 if t: Trace(': bactsig %s != newsig %s' % (bi.bactsig, newsig))
                 result = True
diff --git a/src/engine/SCons/PathListTests.py b/src/engine/SCons/PathListTests.py
index b5989bb..104be73 100644
--- a/src/engine/SCons/PathListTests.py
+++ b/src/engine/SCons/PathListTests.py
@@ -108,7 +108,7 @@ class subst_pathTestCase(unittest.TestCase):
 
         self.env.subst = lambda s, target, source, conv: 'NOT THIS STRING'
 
-        pl = SCons.PathList.PathList(('x'))
+        pl = SCons.PathList.PathList(('x',))
 
         result = pl.subst_path(self.env, 'y', 'z')
 
diff --git a/src/engine/SCons/Platform/virtualenv.py b/src/engine/SCons/Platform/virtualenv.py
index 4127d8c..4708cb2 100644
--- a/src/engine/SCons/Platform/virtualenv.py
+++ b/src/engine/SCons/Platform/virtualenv.py
@@ -61,7 +61,7 @@ def _is_path_in(path, base):
     if not path or not base: # empty path may happen, base too
         return False
     rp = os.path.relpath(path, base)
-    return ((not rp.startswith(os.path.pardir)) and (not rp == os.path.curdir))
+    return (not rp.startswith(os.path.pardir)) and (not rp == os.path.curdir)
 
 
 def _inject_venv_variables(env):
diff --git a/src/engine/SCons/SConf.py b/src/engine/SCons/SConf.py
index 71729c9..e706dae 100644
--- a/src/engine/SCons/SConf.py
+++ b/src/engine/SCons/SConf.py
@@ -270,7 +270,7 @@ class SConfBuildTask(SCons.Taskmaster.AlwaysTask):
         cached_error = False
         cachable = True
         for t in self.targets:
-            if T: Trace('%s' % (t))
+            if T: Trace('%s' % t)
             bi = t.get_stored_info().binfo
             if isinstance(bi, SConfBuildInfo):
                 if T: Trace(': SConfBuildInfo')
@@ -280,7 +280,7 @@ class SConfBuildTask(SCons.Taskmaster.AlwaysTask):
                 else:
                     if T: Trace(': get_state() %s' % t.get_state())
                     if T: Trace(': changed() %s' % t.changed())
-                    if (t.get_state() != SCons.Node.up_to_date and t.changed()):
+                    if t.get_state() != SCons.Node.up_to_date and t.changed():
                         changed = True
                     if T: Trace(': changed %s' % changed)
                 cached_error = cached_error or bi.result
@@ -668,7 +668,7 @@ class SConfBase(object):
         is saved in self.lastTarget (for further processing).
         """
         ok = self.TryLink(text, extension)
-        if( ok ):
+        if ok:
             prog = self.lastTarget
             pname = prog.get_internal_path()
             output = self.confdir.File(os.path.basename(pname)+'.out')
@@ -866,9 +866,9 @@ class CheckContext(object):
         return self.sconf.TryRun(*args, **kw)
 
     def __getattr__( self, attr ):
-        if( attr == 'env' ):
+        if attr == 'env':
             return self.sconf.env
-        elif( attr == 'lastTarget' ):
+        elif attr == 'lastTarget':
             return self.sconf.lastTarget
         else:
             raise AttributeError("CheckContext instance has no attribute '%s'" % attr)
@@ -1067,7 +1067,7 @@ def CheckLibWithHeader(context, libs, header, language,
     """
     prog_prefix, dummy = \
                  createIncludesFromHeaders(header, 0)
-    if libs == []:
+    if not libs:
         libs = [None]
 
     if not SCons.Util.is_List(libs):
diff --git a/src/engine/SCons/SConfTests.py b/src/engine/SCons/SConfTests.py
index 787138e..c5d1fbd 100644
--- a/src/engine/SCons/SConfTests.py
+++ b/src/engine/SCons/SConfTests.py
@@ -151,7 +151,7 @@ class SConfTestCase(unittest.TestCase):
                                  log_file=self.test.workpath('config.log'))
         no_std_header_h = self.test.workpath('config.tests', 'no_std_header.h')
         test_h = self.test.write( no_std_header_h,
-                                  "/* we are changing a dependency now */\n" );
+                                  "/* we are changing a dependency now */\n" )
         try:
             res = checks( self, sconf, TryFunc )
             log = self.test.read( self.test.workpath('config.log') )
diff --git a/src/engine/SCons/Scanner/ScannerTests.py b/src/engine/SCons/Scanner/ScannerTests.py
index 64a2345..abe4042 100644
--- a/src/engine/SCons/Scanner/ScannerTests.py
+++ b/src/engine/SCons/Scanner/ScannerTests.py
@@ -236,7 +236,7 @@ class BaseTestCase(unittest.TestCase):
     def test___cmp__(self):
         """Test the Scanner.Base class __cmp__() method"""
         s = SCons.Scanner.Base(self.func, "Cmp")
-        assert s != None
+        assert s is not None
 
     def test_hash(self):
         """Test the Scanner.Base class __hash__() method"""
@@ -578,8 +578,6 @@ class ClassicTestCase(unittest.TestCase):
                         "recursive = 1 didn't return all nodes: %s" % n)
 
 
-        
-
 class ClassicCPPTestCase(unittest.TestCase):
     def test_find_include(self):
         """Test the Scanner.ClassicCPP find_include() method"""
diff --git a/src/engine/SCons/Script/Main.py b/src/engine/SCons/Script/Main.py
index 238a828..f9c8384 100644
--- a/src/engine/SCons/Script/Main.py
+++ b/src/engine/SCons/Script/Main.py
@@ -355,7 +355,7 @@ class CleanTask(SCons.Taskmaster.AlwaysTask):
                     display("Removed directory " + pathstr)
                 else:
                     errstr = "Path '%s' exists but isn't a file or directory."
-                    raise SCons.Errors.UserError(errstr % (pathstr))
+                    raise SCons.Errors.UserError(errstr % pathstr)
         except SCons.Errors.UserError as e:
             print(e)
         except (IOError, OSError) as e:
diff --git a/src/engine/SCons/Script/SConsOptions.py b/src/engine/SCons/Script/SConsOptions.py
index 66c7239..8ec8ccf 100644
--- a/src/engine/SCons/Script/SConsOptions.py
+++ b/src/engine/SCons/Script/SConsOptions.py
@@ -28,7 +28,7 @@ import re
 import sys
 import textwrap
 
-no_hyphen_re = re.compile(r'(\s+|(?<=[\w\!\"\'\&\.\,\?])-{2,}(?=\w))')
+no_hyphen_re = re.compile(r'(\s+|(?<=[\w!\"\'&.,?])-{2,}(?=\w))')
 
 try:
     from gettext import gettext
diff --git a/src/engine/SCons/Script/__init__.py b/src/engine/SCons/Script/__init__.py
index 9947943..8f526be 100644
--- a/src/engine/SCons/Script/__init__.py
+++ b/src/engine/SCons/Script/__init__.py
@@ -344,7 +344,6 @@ GlobalDefaultEnvironmentFunctions = [
     'Requires',
     'SConsignFile',
     'SideEffect',
-    'SourceCode',
     'Split',
     'Tag',
     'Value',
diff --git a/src/engine/SCons/Subst.py b/src/engine/SCons/Subst.py
index f3693a1..664cd6c 100644
--- a/src/engine/SCons/Subst.py
+++ b/src/engine/SCons/Subst.py
@@ -754,7 +754,7 @@ _list_remove = [ _rm_list, None, _remove_list ]
 #
 _dollar_exps_str = r'\$[\$\(\)]|\$[_a-zA-Z][\.\w]*|\${[^}]*}'
 _dollar_exps = re.compile(r'(%s)' % _dollar_exps_str)
-_separate_args = re.compile(r'(%s|\s+|[^\s\$]+|\$)' % _dollar_exps_str)
+_separate_args = re.compile(r'(%s|\s+|[^\s$]+|\$)' % _dollar_exps_str)
 
 # This regular expression is used to replace strings of multiple white
 # space characters in the string result from the scons_subst() function.
diff --git a/src/engine/SCons/SubstTests.py b/src/engine/SCons/SubstTests.py
index f6fe1ec..c25b377 100644
--- a/src/engine/SCons/SubstTests.py
+++ b/src/engine/SCons/SubstTests.py
@@ -133,8 +133,8 @@ class SubstTestCase(unittest.TestCase):
             return self.value
 
     # only use of this is currently commented out below
-    def function_foo(arg):
-        pass
+    #def function_foo(arg):
+    #    pass
 
     target = [ MyNode("./foo/bar.exe"),
                MyNode("/bar/baz with spaces.obj"),
@@ -207,7 +207,7 @@ class SubstTestCase(unittest.TestCase):
         'S'         : 'x y',
         'LS'        : ['x y'],
         'L'         : ['x', 'y'],
-        'TS'        : ('x y'),
+        'TS'        : ('x y',),
         'T'         : ('x', 'y'),
         'CS'        : cs,
         'CL'        : cl,
diff --git a/src/engine/SCons/Tool/JavaCommon.py b/src/engine/SCons/Tool/JavaCommon.py
index a7e247d..1711de1 100644
--- a/src/engine/SCons/Tool/JavaCommon.py
+++ b/src/engine/SCons/Tool/JavaCommon.py
@@ -40,7 +40,7 @@ default_java_version = '1.4'
 
 # a switch for which jdk versions to use the Scope state for smarter
 # anonymous inner class parsing.
-scopeStateVersions = ('1.8')
+scopeStateVersions = ('1.8',)
 
 # Glob patterns for use in finding where the JDK is.
 # These are pairs, *dir_glob used in the general case,
@@ -87,8 +87,8 @@ if java_parsing:
     #     any alphanumeric token surrounded by angle brackets (generics);
     #     the multi-line comment begin and end tokens /* and */;
     #     array declarations "[]".
-    _reToken = re.compile(r'(\n|\\\\|//|\\[\'"]|[\'"\{\}\;\.\(\)]|' +
-                          r'\d*\.\d*|[A-Za-z_][\w\$\.]*|<[A-Za-z_]\w+>|' +
+    _reToken = re.compile(r'(\n|\\\\|//|\\[\'"]|[\'"{\};.()]|' +
+                          r'\d*\.\d*|[A-Za-z_][\w$.]*|<[A-Za-z_]\w+>|' +
                           r'/\*|\*/|\[\])')
 
 
diff --git a/src/engine/SCons/Tool/MSCommon/common.py b/src/engine/SCons/Tool/MSCommon/common.py
index bbccf61..386f445 100644
--- a/src/engine/SCons/Tool/MSCommon/common.py
+++ b/src/engine/SCons/Tool/MSCommon/common.py
@@ -50,7 +50,7 @@ elif LOGFILE:
         level=logging.DEBUG)
     debug = logging.getLogger(name=__name__).debug
 else:
-    debug = lambda x: None
+    def debug(x): return None
 
 
 # SCONS_CACHE_MSVC_CONFIG is public, and is documented.
@@ -58,6 +58,7 @@ CONFIG_CACHE = os.environ.get('SCONS_CACHE_MSVC_CONFIG')
 if CONFIG_CACHE in ('1', 'true', 'True'):
     CONFIG_CACHE = os.path.join(os.path.expanduser('~'), '.scons_msvc_cache')
 
+
 def read_script_env_cache():
     """ fetch cached msvc env vars if requested, else return empty dict """
     envcache = {}
@@ -65,7 +66,7 @@ def read_script_env_cache():
         try:
             with open(CONFIG_CACHE, 'r') as f:
                 envcache = json.load(f)
-        #TODO can use more specific FileNotFoundError when py2 dropped
+        # TODO can use more specific FileNotFoundError when py2 dropped
         except IOError:
             # don't fail if no cache file, just proceed without it
             pass
@@ -88,6 +89,7 @@ def write_script_env_cache(cache):
 
 _is_win64 = None
 
+
 def is_win64():
     """Return true if running on windows 64 bits.
 
@@ -122,6 +124,7 @@ def is_win64():
 def read_reg(value, hkroot=SCons.Util.HKEY_LOCAL_MACHINE):
     return SCons.Util.RegGetValue(hkroot, value)[0]
 
+
 def has_reg(value):
     """Return True if the given key exists in HKEY_LOCAL_MACHINE, False
     otherwise."""
@@ -134,6 +137,7 @@ def has_reg(value):
 
 # Functions for fetching environment variable settings from batch files.
 
+
 def normalize_env(env, keys, force=False):
     """Given a dictionary representing a shell environment, add the variables
     from os.environ needed for the processing of .bat files; the keys are
@@ -172,11 +176,12 @@ def normalize_env(env, keys, force=False):
     if sys32_wbem_dir not in normenv['PATH']:
         normenv['PATH'] = normenv['PATH'] + os.pathsep + sys32_wbem_dir
 
-    debug("PATH: %s"%normenv['PATH'])
+    debug("PATH: %s" % normenv['PATH'])
 
     return normenv
 
-def get_output(vcbat, args = None, env = None):
+
+def get_output(vcbat, args=None, env=None):
     """Parse the output of given bat file, with given args."""
 
     if env is None:
@@ -242,7 +247,13 @@ def get_output(vcbat, args = None, env = None):
     output = stdout.decode("mbcs")
     return output
 
-KEEPLIST = ("INCLUDE", "LIB", "LIBPATH", "PATH", 'VSCMD_ARG_app_plat')
+
+KEEPLIST = ("INCLUDE", "LIB", "LIBPATH", "PATH", 'VSCMD_ARG_app_plat',
+            'VCINSTALLDIR',  # needed by clang -VS 2017 and newer
+            'VCToolsInstallDir', # needed by clang - VS 2015 and older
+            )
+
+
 def parse_output(output, keep=KEEPLIST):
     """
     Parse output from running visual c++/studios vcvarsall.bat and running set
diff --git a/src/engine/SCons/Tool/MSCommon/sdk.py b/src/engine/SCons/Tool/MSCommon/sdk.py
index 281c1e3..9627f17 100644
--- a/src/engine/SCons/Tool/MSCommon/sdk.py
+++ b/src/engine/SCons/Tool/MSCommon/sdk.py
@@ -110,12 +110,12 @@ class SDKDefinition(object):
         """ Return the script to initialize the VC compiler installed by SDK
         """
 
-        if (host_arch == 'amd64' and target_arch == 'x86'):
+        if host_arch == 'amd64' and target_arch == 'x86':
             # No cross tools needed compiling 32 bits on 64 bit machine
             host_arch=target_arch
 
         arch_string=target_arch
-        if (host_arch != target_arch):
+        if host_arch != target_arch:
             arch_string='%s_%s'%(host_arch,target_arch)
 
         debug("get_sdk_vc_script():arch_string:%s host_arch:%s target_arch:%s"%(arch_string,
diff --git a/src/engine/SCons/Tool/MSCommon/vc.py b/src/engine/SCons/Tool/MSCommon/vc.py
index 86bdbe0..6f9bd12 100644
--- a/src/engine/SCons/Tool/MSCommon/vc.py
+++ b/src/engine/SCons/Tool/MSCommon/vc.py
@@ -509,7 +509,7 @@ def _check_cl_exists_in_vc_dir(env, vc_dir, msvc_version):
             debug('_check_cl_exists_in_vc_dir(): found ' + _CL_EXE_NAME + '!')
             return True
 
-    elif ver_num <= 14 and ver_num >= 8:
+    elif 14 >= ver_num >= 8:
 
         # Set default value to be -1 as "" which is the value for x86/x86 yields true when tested
         # if not host_trgt_dir
@@ -541,7 +541,7 @@ def _check_cl_exists_in_vc_dir(env, vc_dir, msvc_version):
             debug('_check_cl_exists_in_vc_dir(): found ' + _CL_EXE_NAME + '!')
             return True
 
-    elif ver_num < 8 and ver_num >= 6:
+    elif 8 > ver_num >= 6:
         # not sure about these versions so if a walk the VC dir (could be slow)
         for root, _, files in os.walk(vc_dir):
             if _CL_EXE_NAME in files:
@@ -766,12 +766,12 @@ def msvc_find_valid_batch_script(env, version):
                 vc_script=None
                 continue
         if not vc_script and sdk_script:
-            debug('msvc_find_valid_batch_script() use_script 4: trying sdk script: %s'%(sdk_script))
+            debug('msvc_find_valid_batch_script() use_script 4: trying sdk script: %s' % sdk_script)
             try:
                 d = script_env(sdk_script)
                 found = sdk_script
             except BatchFileExecutionError as e:
-                debug('msvc_find_valid_batch_script() use_script 5: failed running SDK script %s: Error:%s'%(repr(sdk_script),e))
+                debug('msvc_find_valid_batch_script() use_script 5: failed running SDK script %s: Error:%s'%(repr(sdk_script), e))
                 continue
         elif not vc_script and not sdk_script:
             debug('msvc_find_valid_batch_script() use_script 6: Neither VC script nor SDK script found')
diff --git a/src/engine/SCons/Tool/__init__.py b/src/engine/SCons/Tool/__init__.py
index f255b21..14306ab 100644
--- a/src/engine/SCons/Tool/__init__.py
+++ b/src/engine/SCons/Tool/__init__.py
@@ -774,11 +774,11 @@ def EmitLibSymlinks(env, symlinks, libnode, **kw):
 
     for link, linktgt in symlinks:
         env.SideEffect(link, linktgt)
-        if (Verbose):
+        if Verbose:
             print("EmitLibSymlinks: SideEffect(%r,%r)" % (link.get_path(), linktgt.get_path()))
         clean_list = [x for x in nodes if x != linktgt]
         env.Clean(list(set([linktgt] + clean_targets)), clean_list)
-        if (Verbose):
+        if Verbose:
             print("EmitLibSymlinks: Clean(%r,%r)" % (linktgt.get_path(), [x.get_path() for x in clean_list]))
 
 
@@ -792,18 +792,18 @@ def CreateLibSymlinks(env, symlinks):
     for link, linktgt in symlinks:
         linktgt = link.get_dir().rel_path(linktgt)
         link = link.get_path()
-        if (Verbose):
+        if Verbose:
             print("CreateLibSymlinks: preparing to add symlink %r -> %r" % (link, linktgt))
         # Delete the (previously created) symlink if exists. Let only symlinks
         # to be deleted to prevent accidental deletion of source files...
         if env.fs.islink(link):
             env.fs.unlink(link)
-            if (Verbose):
+            if Verbose:
                 print("CreateLibSymlinks: removed old symlink %r" % link)
         # If a file or directory exists with the same name as link, an OSError
         # will be thrown, which should be enough, I think.
         env.fs.symlink(linktgt, link)
-        if (Verbose):
+        if Verbose:
             print("CreateLibSymlinks: add symlink %r -> %r" % (link, linktgt))
     return 0
 
diff --git a/src/engine/SCons/Tool/clang.py b/src/engine/SCons/Tool/clang.py
index 081ab67..162daad 100644
--- a/src/engine/SCons/Tool/clang.py
+++ b/src/engine/SCons/Tool/clang.py
@@ -46,6 +46,7 @@ import sys
 import SCons.Util
 import SCons.Tool.cc
 from SCons.Tool.clangCommon import get_clang_install_dirs
+from SCons.Tool.MSCommon import msvc_setup_env_once
 
 
 compilers = ['clang']
@@ -62,6 +63,10 @@ def generate(env):
             clang_bin_dir = os.path.dirname(clang)
             env.AppendENVPath('PATH', clang_bin_dir)
 
+            # Set-up ms tools paths
+            msvc_setup_env_once(env)
+
+
     env['CC'] = env.Detect(compilers) or 'clang'
     if env['PLATFORM'] in ['cygwin', 'win32']:
         env['SHCCFLAGS'] = SCons.Util.CLVar('$CCFLAGS')
diff --git a/src/engine/SCons/Tool/clangCommon/__init__.py b/src/engine/SCons/Tool/clangCommon/__init__.py
index 37efbf6..5501457 100644
--- a/src/engine/SCons/Tool/clangCommon/__init__.py
+++ b/src/engine/SCons/Tool/clangCommon/__init__.py
@@ -6,6 +6,7 @@ clang_win32_dirs = [
     r'C:\Program Files\LLVM\bin',
     r'C:\cygwin64\bin',
     r'C:\msys64',
+    r'C:\msys64\mingw64\bin',
     r'C:\cygwin\bin',
     r'C:\msys',
 ]
diff --git a/src/engine/SCons/Tool/clangxx.py b/src/engine/SCons/Tool/clangxx.py
index a29cf79..b1dc6f3 100644
--- a/src/engine/SCons/Tool/clangxx.py
+++ b/src/engine/SCons/Tool/clangxx.py
@@ -47,6 +47,7 @@ import SCons.Tool
 import SCons.Util
 import SCons.Tool.cxx
 from SCons.Tool.clangCommon import get_clang_install_dirs
+from SCons.Tool.MSCommon import msvc_setup_env_once
 
 
 compilers = ['clang++']
@@ -75,6 +76,10 @@ def generate(env):
             clangxx_bin_dir = os.path.dirname(clangxx)
             env.AppendENVPath('PATH', clangxx_bin_dir)
 
+            # Set-up ms tools paths
+            msvc_setup_env_once(env)
+
+
     # determine compiler version
     if env['CXX']:
         pipe = SCons.Action._subproc(env, [env['CXX'], '--version'],
diff --git a/src/engine/SCons/Tool/docbook/__init__.py b/src/engine/SCons/Tool/docbook/__init__.py
index b93d916..c4fdfba 100644
--- a/src/engine/SCons/Tool/docbook/__init__.py
+++ b/src/engine/SCons/Tool/docbook/__init__.py
@@ -135,7 +135,7 @@ def __get_xml_text(root):
     """ Return the text for the given root node (xml.dom.minidom). """
     txt = ""
     for e in root.childNodes:
-        if (e.nodeType == e.TEXT_NODE):
+        if e.nodeType == e.TEXT_NODE:
             txt += e.data
     return txt
 
@@ -207,7 +207,7 @@ def _detect(env):
     if env.get('DOCBOOK_PREFER_XSLTPROC',''):
         prefer_xsltproc = True
 
-    if ((not has_libxml2 and not has_lxml) or (prefer_xsltproc)):
+    if (not has_libxml2 and not has_lxml) or prefer_xsltproc:
         # Try to find the XSLT processors
         __detect_cl_tool(env, 'DOCBOOK_XSLTPROC', xsltproc_com, xsltproc_com_priority)
         __detect_cl_tool(env, 'DOCBOOK_XMLLINT', xmllint_com)
diff --git a/src/engine/SCons/Tool/docbook/docbook-xsl-1.76.1/extensions/docbook.py b/src/engine/SCons/Tool/docbook/docbook-xsl-1.76.1/extensions/docbook.py
index e7b8cfa..de1375d 100644
--- a/src/engine/SCons/Tool/docbook/docbook-xsl-1.76.1/extensions/docbook.py
+++ b/src/engine/SCons/Tool/docbook/docbook-xsl-1.76.1/extensions/docbook.py
@@ -33,10 +33,10 @@ def adjustColumnWidths(ctx, nodeset):
 
     # Get the nominal table width
     varString = lookupVariable(tctxt, "nominal.table.width", None)
-    if varString == None:
-        nominalWidth = 6 * pixelsPerInch;
+    if varString is None:
+        nominalWidth = 6 * pixelsPerInch
     else:
-        nominalWidth = convertLength(varString);
+        nominalWidth = convertLength(varString)
 
     # Get the requested table width
     tableWidth = lookupVariable(tctxt, "table.width", "100%")
@@ -58,13 +58,13 @@ def adjustColumnWidths(ctx, nodeset):
         colChildren = colgroup.children
 
     col = colChildren
-    while col != None:
+    while col is not None:
         if foStylesheet:
             width = col.prop("column-width")
         else:
             width = col.prop("width")
 
-        if width == None:
+        if width is None:
             width = "1*"
 
         relPart = 0.0
@@ -145,7 +145,7 @@ def adjustColumnWidths(ctx, nodeset):
     # Side-effect free? We don' need no steenkin' side-effect free!
     count = 0
     col = colChildren
-    while col != None:
+    while col is not None:
         if foStylesheet:
             col.setProp("column-width", widths[count])
         else:
@@ -161,8 +161,8 @@ def convertLength(length):
     global pixelsPerInch
     global unitHash
 
-    m = re.search('([+-]?[\d\.]+)(\S+)', length)
-    if m != None and m.lastindex > 1:
+    m = re.search('([+-]?[\d.]+)(\S+)', length)
+    if m is not None and m.lastindex > 1:
         unit = pixelsPerInch
         if m.group(2) in unitHash:
             unit = unitHash[m.group(2)]
@@ -204,7 +204,7 @@ def correctRoundingError(floatWidths):
 
 def lookupVariable(tctxt, varName, default):
     varString = tctxt.variableLookup(varName, None)
-    if varString == None:
+    if varString is None:
         return default
 
     # If it's a list, get the first element
diff --git a/src/engine/SCons/Tool/docbook/docbook-xsl-1.76.1/extensions/xslt.py b/src/engine/SCons/Tool/docbook/docbook-xsl-1.76.1/extensions/xslt.py
index 77ca0de..d5529b8 100644
--- a/src/engine/SCons/Tool/docbook/docbook-xsl-1.76.1/extensions/xslt.py
+++ b/src/engine/SCons/Tool/docbook/docbook-xsl-1.76.1/extensions/xslt.py
@@ -36,7 +36,7 @@ try:
         outfile = None
 
     count = 4
-    while (sys.argv[count]):
+    while sys.argv[count]:
         try:
             name, value = sys.argv[count].split("=", 2)
             if name in params:
diff --git a/src/engine/SCons/Tool/install.py b/src/engine/SCons/Tool/install.py
index c0a193b..dcb3581 100644
--- a/src/engine/SCons/Tool/install.py
+++ b/src/engine/SCons/Tool/install.py
@@ -168,7 +168,7 @@ def installShlibLinks(dest, source, env):
     Verbose = False
     symlinks = listShlibLinksToInstall(dest, source, env)
     if Verbose:
-        print('installShlibLinks: symlinks={:r}'.format(SCons.Tool.StringizeLibSymlinks(symlinks)))
+        print('installShlibLinks: symlinks={!r}'.format(SCons.Tool.StringizeLibSymlinks(symlinks)))
     if symlinks:
         SCons.Tool.CreateLibSymlinks(env, symlinks)
     return
@@ -244,7 +244,7 @@ def add_versioned_targets_to_INSTALLED_FILES(target, source, env):
     Verbose = False
     _INSTALLED_FILES.extend(target)
     if Verbose:
-        print("add_versioned_targets_to_INSTALLED_FILES: target={:r}".format(list(map(str, target))))
+        print("add_versioned_targets_to_INSTALLED_FILES: target={!r}".format(list(map(str, target))))
     symlinks = listShlibLinksToInstall(target[0], source, env)
     if symlinks:
         SCons.Tool.EmitLibSymlinks(env, symlinks, target[0])
diff --git a/src/engine/SCons/Tool/intelc.py b/src/engine/SCons/Tool/intelc.py
index 7550c34..5a101b4 100644
--- a/src/engine/SCons/Tool/intelc.py
+++ b/src/engine/SCons/Tool/intelc.py
@@ -318,7 +318,7 @@ def get_intel_compiler_top(version, abi):
         if not os.path.exists(os.path.join(top, "Bin", "icl.exe")) \
               and not os.path.exists(os.path.join(top, "Bin", abi, "icl.exe")) \
               and not os.path.exists(os.path.join(top, "Bin", archdir, "icl.exe")):
-            raise MissingDirError("Can't find Intel compiler in %s"%(top))
+            raise MissingDirError("Can't find Intel compiler in %s" % top)
     elif is_mac or is_linux:
         def find_in_2008style_dir(version):
             # first dir is new (>=9.0) style, second is old (8.0) style.
diff --git a/src/engine/SCons/Tool/jar.py b/src/engine/SCons/Tool/jar.py
index e75fa13..502aa60 100644
--- a/src/engine/SCons/Tool/jar.py
+++ b/src/engine/SCons/Tool/jar.py
@@ -158,7 +158,7 @@ def Jar(env, target = None, source = [], *args, **kw):
     #       files.
     def dir_to_class(s):
         dir_targets = env.JavaClassDir(source = s, *args, **kw)
-        if(dir_targets == []):
+        if dir_targets == []:
             # no classes files could be built from the source dir
             # so pass the dir as is.
             return [env.fs.Dir(s)]
diff --git a/src/engine/SCons/Tool/javah.py b/src/engine/SCons/Tool/javah.py
index 80f8a6b..fbfcbe2 100644
--- a/src/engine/SCons/Tool/javah.py
+++ b/src/engine/SCons/Tool/javah.py
@@ -115,7 +115,7 @@ def getJavaHClassPath(env,target, source, for_signature):
     path = "${SOURCE.attributes.java_classdir}"
     if 'JAVACLASSPATH' in env and env['JAVACLASSPATH']:
         path = SCons.Util.AppendPath(path, env['JAVACLASSPATH'])
-    return "-classpath %s" % (path)
+    return "-classpath %s" % path
 
 def generate(env):
     """Add Builders and construction variables for javah to an Environment."""
diff --git a/src/engine/SCons/Tool/mslink.py b/src/engine/SCons/Tool/mslink.py
index 0fa6454..fc5f009 100644
--- a/src/engine/SCons/Tool/mslink.py
+++ b/src/engine/SCons/Tool/mslink.py
@@ -220,7 +220,7 @@ def embedManifestDllCheck(target, source, env):
     if env.get('WINDOWS_EMBED_MANIFEST', 0):
         manifestSrc = target[0].get_abspath() + '.manifest'
         if os.path.exists(manifestSrc):
-            ret = (embedManifestDllAction) ([target[0]],None,env)
+            ret = embedManifestDllAction([target[0]], None, env)
             if ret:
                 raise SCons.Errors.UserError("Unable to embed manifest into %s" % (target[0]))
             return ret
@@ -234,7 +234,7 @@ def embedManifestExeCheck(target, source, env):
     if env.get('WINDOWS_EMBED_MANIFEST', 0):
         manifestSrc = target[0].get_abspath() + '.manifest'
         if os.path.exists(manifestSrc):
-            ret = (embedManifestExeAction) ([target[0]],None,env)
+            ret = embedManifestExeAction([target[0]], None, env)
             if ret:
                 raise SCons.Errors.UserError("Unable to embed manifest into %s" % (target[0]))
             return ret
diff --git a/src/engine/SCons/Tool/msvs.py b/src/engine/SCons/Tool/msvs.py
index 7dca9e1..929e558 100644
--- a/src/engine/SCons/Tool/msvs.py
+++ b/src/engine/SCons/Tool/msvs.py
@@ -172,9 +172,9 @@ def makeHierarchy(sources):
     return hierarchy
 
 class _UserGenerator(object):
-    '''
+    """
     Base class for .dsp.user file generator
-    '''
+    """
     # Default instance values.
     # Ok ... a bit defensive, but it does not seem reasonable to crash the
     # build for a workspace user file. :-)
@@ -980,7 +980,7 @@ class _GenerateV7DSP(_DSPGenerator, _GenerateV7User):
             if SCons.Util.is_Dict(value):
                 self.file.write('\t\t\t<Filter\n'
                                 '\t\t\t\tName="%s"\n'
-                                '\t\t\t\tFilter="">\n' % (key))
+                                '\t\t\t\tFilter="">\n' % key)
                 self.printSources(value, commonprefix)
                 self.file.write('\t\t\t</Filter>\n')
 
@@ -992,7 +992,7 @@ class _GenerateV7DSP(_DSPGenerator, _GenerateV7User):
                 file = os.path.normpath(file)
                 self.file.write('\t\t\t<File\n'
                                 '\t\t\t\tRelativePath="%s">\n'
-                                '\t\t\t</File>\n' % (file))
+                                '\t\t\t</File>\n' % file)
 
     def PrintSourceFiles(self):
         categories = {'Source Files': 'cpp;c;cxx;l;y;def;odl;idl;hpj;bat',
@@ -2047,17 +2047,17 @@ def generate(env):
         (version_num, suite) = (7.0, None) # guess at a default
     if 'MSVS' not in env:
         env['MSVS'] = {}
-    if (version_num < 7.0):
+    if version_num < 7.0:
         env['MSVS']['PROJECTSUFFIX']  = '.dsp'
         env['MSVS']['SOLUTIONSUFFIX'] = '.dsw'
-    elif (version_num < 10.0):
+    elif version_num < 10.0:
         env['MSVS']['PROJECTSUFFIX']  = '.vcproj'
         env['MSVS']['SOLUTIONSUFFIX'] = '.sln'
     else:
         env['MSVS']['PROJECTSUFFIX']  = '.vcxproj'
         env['MSVS']['SOLUTIONSUFFIX'] = '.sln'
 
-    if (version_num >= 10.0):
+    if version_num >= 10.0:
         env['MSVSENCODING'] = 'utf-8'
     else:
         env['MSVSENCODING'] = 'Windows-1252'
diff --git a/src/engine/SCons/Tool/packaging/msi.py b/src/engine/SCons/Tool/packaging/msi.py
index 34e4f0f..9f28b72 100644
--- a/src/engine/SCons/Tool/packaging/msi.py
+++ b/src/engine/SCons/Tool/packaging/msi.py
@@ -182,7 +182,7 @@ def generate_guids(root):
 
 
 def string_wxsfile(target, source, env):
-    return "building WiX file %s"%( target[0].path )
+    return "building WiX file %s" % target[0].path
 
 def build_wxsfile(target, source, env):
     """ Compiles a .wxs file from the keywords given in env['msi_spec'] and
diff --git a/src/engine/SCons/Tool/tex.py b/src/engine/SCons/Tool/tex.py
index 5cf7bca..fa18cf9 100644
--- a/src/engine/SCons/Tool/tex.py
+++ b/src/engine/SCons/Tool/tex.py
@@ -204,7 +204,7 @@ def InternalLaTeXAuxAction(XXXLaTeXAction, target = None, source= None, env=None
     # with LaTeXAction and from the pdflatex.py with PDFLaTeXAction
     # set this up now for the case where the user requests a different extension
     # for the target filename
-    if (XXXLaTeXAction == LaTeXAction):
+    if XXXLaTeXAction == LaTeXAction:
        callerSuffix = ".dvi"
     else:
        callerSuffix = env['PDFSUFFIX']
@@ -283,7 +283,7 @@ def InternalLaTeXAuxAction(XXXLaTeXAction, target = None, source= None, env=None
 
     count = 0
 
-    while (must_rerun_latex and count < int(env.subst('$LATEXRETRIES'))) :
+    while must_rerun_latex and count < int(env.subst('$LATEXRETRIES')):
         result = XXXLaTeXAction(target, source, env)
         if result != 0:
             return result
@@ -461,7 +461,7 @@ def InternalLaTeXAuxAction(XXXLaTeXAction, target = None, source= None, env=None
             if Verbose:
                 print("rerun Latex due to undefined references or citations")
 
-        if (count >= int(env.subst('$LATEXRETRIES')) and must_rerun_latex):
+        if count >= int(env.subst('$LATEXRETRIES')) and must_rerun_latex:
             print("reached max number of retries on Latex ,",int(env.subst('$LATEXRETRIES')))
 # end of while loop
 
@@ -861,7 +861,7 @@ def generate_darwin(env):
         environ = {}
         env['ENV'] = environ
 
-    if (platform.system() == 'Darwin'):
+    if platform.system() == 'Darwin':
         try:
             ospath = env['ENV']['PATHOSX']
         except:
diff --git a/src/engine/SCons/Tool/xgettext.py b/src/engine/SCons/Tool/xgettext.py
index 936924b..11ca32f 100644
--- a/src/engine/SCons/Tool/xgettext.py
+++ b/src/engine/SCons/Tool/xgettext.py
@@ -133,7 +133,7 @@ def _update_pot_file(target, source, env):
             re_cdate = re.compile(r'^"POT-Creation-Date: .*"$[\r\n]?', re.M)
             old_content_nocdate = re.sub(re_cdate, "", old_content)
             new_content_nocdate = re.sub(re_cdate, "", new_content)
-            if (old_content_nocdate == new_content_nocdate):
+            if old_content_nocdate == new_content_nocdate:
                 # Messages are up-to-date
                 needs_update = False
                 explain = "messages in file found to be up-to-date"
diff --git a/src/engine/SCons/Util.py b/src/engine/SCons/Util.py
index 8519a98..4b4ead5 100644
--- a/src/engine/SCons/Util.py
+++ b/src/engine/SCons/Util.py
@@ -312,18 +312,21 @@ def print_tree(root, child_func, prune=0, showtags=0, margin=[0], visited=None):
                       '\n')
             sys.stdout.write(legend)
 
-        tags = ['[']
-        tags.append(' E'[IDX(root.exists())])
-        tags.append(' R'[IDX(root.rexists() and not root.exists())])
-        tags.append(' BbB'[[0,1][IDX(root.has_explicit_builder())] +
-                           [0,2][IDX(root.has_builder())]])
-        tags.append(' S'[IDX(root.side_effect)])
-        tags.append(' P'[IDX(root.precious)])
-        tags.append(' A'[IDX(root.always_build)])
-        tags.append(' C'[IDX(root.is_up_to_date())])
-        tags.append(' N'[IDX(root.noclean)])
-        tags.append(' H'[IDX(root.nocache)])
-        tags.append(']')
+        tags = [
+            '[',
+            ' E'[IDX(root.exists())],
+            ' R'[IDX(root.rexists() and not root.exists())],
+            ' BbB'[
+                [0, 1][IDX(root.has_explicit_builder())] +
+                [0, 2][IDX(root.has_builder())]
+            ],
+            ' S'[IDX(root.side_effect)], ' P'[IDX(root.precious)],
+            ' A'[IDX(root.always_build)],
+            ' C'[IDX(root.is_up_to_date())],
+            ' N'[IDX(root.noclean)],
+            ' H'[IDX(root.nocache)],
+            ']'
+        ]
 
     else:
         tags = []
@@ -352,7 +355,6 @@ def print_tree(root, child_func, prune=0, showtags=0, margin=[0], visited=None):
         margin.pop()
 
 
-
 # Functions for deciding if things are like various types, mainly to
 # handle UserDict, UserList and UserString like their underlying types.
 #
@@ -390,7 +392,7 @@ except NameError:
 try:
     BaseStringTypes = (str, unicode)
 except NameError:
-    BaseStringTypes = (str)
+    BaseStringTypes = str
 
 def is_Dict(obj, isinstance=isinstance, DictTypes=DictTypes):
     return isinstance(obj, DictTypes)
diff --git a/src/engine/SCons/UtilTests.py b/src/engine/SCons/UtilTests.py
index 0017844..7f6508d 100644
--- a/src/engine/SCons/UtilTests.py
+++ b/src/engine/SCons/UtilTests.py
@@ -451,11 +451,11 @@ class UtilTestCase(unittest.TestCase):
         assert get_environment_var("${BAR}") == "BAR", get_environment_var("${BAR}")
         assert get_environment_var("$FOO_BAR1234") == "FOO_BAR1234", get_environment_var("$FOO_BAR1234")
         assert get_environment_var("${BAR_FOO1234}") == "BAR_FOO1234", get_environment_var("${BAR_FOO1234}")
-        assert get_environment_var("${BAR}FOO") == None, get_environment_var("${BAR}FOO")
-        assert get_environment_var("$BAR ") == None, get_environment_var("$BAR ")
-        assert get_environment_var("FOO$BAR") == None, get_environment_var("FOO$BAR")
-        assert get_environment_var("$FOO[0]") == None, get_environment_var("$FOO[0]")
-        assert get_environment_var("${some('complex expression')}") == None, get_environment_var(
+        assert get_environment_var("${BAR}FOO") is None, get_environment_var("${BAR}FOO")
+        assert get_environment_var("$BAR ") is None, get_environment_var("$BAR ")
+        assert get_environment_var("FOO$BAR") is None, get_environment_var("FOO$BAR")
+        assert get_environment_var("$FOO[0]") is None, get_environment_var("$FOO[0]")
+        assert get_environment_var("${some('complex expression')}") is None, get_environment_var(
             "${some('complex expression')}")
 
     def test_Proxy(self):
diff --git a/src/engine/SCons/dblite.py b/src/engine/SCons/dblite.py
index 14bd93d..55254b3 100644
--- a/src/engine/SCons/dblite.py
+++ b/src/engine/SCons/dblite.py
@@ -131,9 +131,10 @@ class dblite(object):
                         # Note how we catch KeyErrors too here, which might happen
                         # when we don't have cPickle available (default pickle
                         # throws it).
-                        if (ignore_corrupt_dbfiles == 0): raise
-                        if (ignore_corrupt_dbfiles == 1):
+                        if ignore_corrupt_dbfiles:
                             corruption_warning(self._file_name)
+                        else:
+                            raise
 
     def close(self):
         if self._needs_sync:
@@ -166,13 +167,13 @@ class dblite(object):
             except OSError:
                 pass
         self._needs_sync = 00000
-        if (keep_all_files):
+        if keep_all_files:
             self._shutil_copyfile(
                 self._file_name,
                 self._file_name + "_" + str(int(self._time_time())))
 
     def _check_writable(self):
-        if (self._flag == "r"):
+        if self._flag == "r":
             raise IOError("Read-only database: %s" % self._file_name)
 
     def __getitem__(self, key):
@@ -180,9 +181,9 @@ class dblite(object):
 
     def __setitem__(self, key, value):
         self._check_writable()
-        if (not is_string(key)):
+        if not is_string(key):
             raise TypeError("key `%s' must be a string but is %s" % (key, type(key)))
-        if (not is_bytes(value)):
+        if not is_bytes(value):
             raise TypeError("value `%s' must be a bytes but is %s" % (value, type(value)))
         self._dict[key] = value
         self._needs_sync = 0o001
@@ -280,7 +281,7 @@ def _exercise():
         raise RuntimeError("IOError expected.")
 
 
-if (__name__ == "__main__"):
+if __name__ == "__main__":
     _exercise()
 
 # Local Variables: