Fixup some code triggering pylint errors.

Assorted fixups: exception types, redefined functions, globals, etc.

Some old code removed to resolve issues (hashlib is always present on
modern Pythons; no longer need the code for 2.5-and-earlier optparse).

cmp is not a builtin function in Py3, drop one (unused) use; replace one.

Fix another instance of renaming to SConsEnvironmentError.

TODO flagged some instances of doing a raise without argument but not
inside a try block - this is not considered legal, since raise
with no argument is for re-raising an exception, but I don't know
exactly how to resolve this in these cases. Also flagged an instance
of raising an int instead of an exception class. We can either leave
these as markers or update the PR.

Signed-off-by: Mats Wichmann <mats@linux.com>

2 files changed, 23 insertions, 54 deletions

diff --git a/src/engine/SCons/Script/Main.py b/src/engine/SCons/Script/Main.py
index f3475f2..fdcd252 100644
--- a/src/engine/SCons/Script/Main.py
+++ b/src/engine/SCons/Script/Main.py
@@ -68,6 +68,20 @@ import SCons.Warnings
 
 import SCons.Script.Interactive
 
+# Global variables
+first_command_start = None
+last_command_end = None
+print_objects = 0
+print_memoizer = 0
+print_stacktrace = 0
+print_time = 0
+sconscript_time = 0
+cumulative_command_time = 0
+exit_status = 0   # final exit status, assume success by default
+this_build_status = 0   # "exit status" of an individual build
+num_jobs = None
+delayed_warnings = []
+
 
 def fetch_win32_parallel_msg():
     # A subsidiary function that exists solely to isolate this import
@@ -87,15 +101,14 @@ def revert_io():
     sys.stderr = sys.__stderr__
     sys.stdout = sys.__stdout__
 
+
 class SConsPrintHelpException(Exception):
     pass
 
+
 display = SCons.Util.display
 progress_display = SCons.Util.DisplayEngine()
 
-first_command_start = None
-last_command_end = None
-
 
 class Progressor(object):
     prev = ''
@@ -443,19 +456,6 @@ def python_version_deprecated(version=sys.version_info):
     return version < deprecated_python_version
 
 
-# Global variables
-
-print_objects = 0
-print_memoizer = 0
-print_stacktrace = 0
-print_time = 0
-sconscript_time = 0
-cumulative_command_time = 0
-exit_status = 0 # final exit status, assume success by default
-this_build_status = 0 # "exit status" of an individual build
-num_jobs = None
-delayed_warnings = []
-
 class FakeOptionParser(object):
     """
     A do-nothing option parser, used for the initial OptionsParser variable.
diff --git a/src/engine/SCons/Script/SConsOptions.py b/src/engine/SCons/Script/SConsOptions.py
index 37dd644..01d365d 100644
--- a/src/engine/SCons/Script/SConsOptions.py
+++ b/src/engine/SCons/Script/SConsOptions.py
@@ -226,39 +226,8 @@ class SConsOption(optparse.Option):
             fmt = "option %s: nargs='?' is incompatible with short options"
             raise SCons.Errors.UserError(fmt % self._short_opts[0])
 
-    try:
-        _orig_CONST_ACTIONS = optparse.Option.CONST_ACTIONS
-
-        _orig_CHECK_METHODS = optparse.Option.CHECK_METHODS
-
-    except AttributeError:
-        # optparse.Option had no CONST_ACTIONS before Python 2.5.
-
-        _orig_CONST_ACTIONS = ("store_const",)
-
-        def _check_const(self):
-            if self.action not in self.CONST_ACTIONS and self.const is not None:
-                raise OptionError(
-                    "'const' must not be supplied for action %r" % self.action,
-                    self)
-
-        # optparse.Option collects its list of unbound check functions
-        # up front.  This sucks because it means we can't just override
-        # the _check_const() function like a normal method, we have to
-        # actually replace it in the list.  This seems to be the most
-        # straightforward way to do that.
-
-        _orig_CHECK_METHODS = [optparse.Option._check_action,
-                     optparse.Option._check_type,
-                     optparse.Option._check_choice,
-                     optparse.Option._check_dest,
-                     _check_const,
-                     optparse.Option._check_nargs,
-                     optparse.Option._check_callback]
-
-    CHECK_METHODS = _orig_CHECK_METHODS + [_check_nargs_optional]
-
-    CONST_ACTIONS = _orig_CONST_ACTIONS + optparse.Option.TYPED_ACTIONS
+    CHECK_METHODS = optparse.Option.CHECK_METHODS + [_check_nargs_optional]
+    CONST_ACTIONS = optparse.Option.CONST_ACTIONS + optparse.Option.TYPED_ACTIONS
 
 class SConsOptionGroup(optparse.OptionGroup):
     """
@@ -364,7 +333,7 @@ class SConsOptionParser(optparse.OptionParser):
         in self.largs, so that any value overridden on the
         command line is immediately available if the user turns
         around and does a GetOption() right away.
-        
+
         We mimic the processing of the single args
         in the original OptionParser._process_args(), but here we
         allow exact matches for long-opts only (no partial
@@ -375,7 +344,7 @@ class SConsOptionParser(optparse.OptionParser):
         command-line arguments that
           1. haven't been processed so far (self.largs), but
           2. are possibly not added to the list of options yet.
-          
+
         So, when we only have a value for "--myargument" yet,
         a command-line argument of "--myarg=test" would set it.
         Responsible for this behaviour is the method
@@ -384,7 +353,7 @@ class SConsOptionParser(optparse.OptionParser):
         be unique.
         This would lead to further confusion, because we might want
         to add another option "--myarg" later on (see issue #2929).
-        
+
         """
         rargs = []
         largs_restore = []
@@ -401,7 +370,7 @@ class SConsOptionParser(optparse.OptionParser):
                     if "=" in l:
                         # Split into option and value
                         lopt = l.split("=", 1)
-                        
+
                     if lopt[0] in self._long_opt:
                         # Argument is already known
                         rargs.append('='.join(lopt))
@@ -416,7 +385,7 @@ class SConsOptionParser(optparse.OptionParser):
                         skip = True
                     else:
                         rargs.append(l)
-        
+
         # Parse the filtered list
         self.parse_args(rargs, self.values)
         # Restore the list of remaining arguments for the