[roottest] Make ruff happier with custom_diff.py

Author: hageboeck

roottest/scripts/custom_diff.py

@@ -1,12 +1,18 @@
 """ Clever (with filters) compare command using difflib.py providing diffs in four formats:
-  
+
   * ndiff:    lists every line and highlights interline changes.
   * context:  highlights clusters of changes in a before/after format.
   * unified:  highlights clusters of changes in an inline format.
   * html:     generates side by side comparison with change highlights.
-  
+
   """
-import sys, os, time, difflib, optparse, re
+import difflib
+import optparse
+import os
+import re
+import sys
+import time
+
 #---------------------------------------------------------------------------------------------------------------------------
 #---Filter and substitutions------------------------------------------------------------------------------------------------
 
@@ -67,16 +73,16 @@ def main():
   parser.add_option("-n", action="store_true", default=False, help='Produce a ndiff format diff')
   parser.add_option("-l", "--lines", type="int", default=3, help='Set number of context lines (default 3)')
   (options, args) = parser.parse_args()
-  
+
   if len(args) == 0:
     parser.print_help()
     sys.exit(1)
   if len(args) != 2:
     parser.error("need to specify both a fromfile and tofile")
-  
+
   n = options.lines
   fromfile, tofile = args
-  
+
   fromdate = time.ctime(os.stat(fromfile).st_mtime)
   todate = time.ctime(os.stat(tofile).st_mtime)
   if sys.platform == 'win32':
@@ -91,7 +97,7 @@ def main():
 
   check = difflib.context_diff(nows_fromlines, nows_tolines)
   try:
-    first = next(check)
+    _ = next(check)
   except StopIteration:
     sys.exit(0)
 
@@ -106,12 +112,14 @@ def main():
     diff = difflib.HtmlDiff().make_file(fromlines,tolines,fromfile,tofile,context=options.c,numlines=n)
   else:
     diff = difflib.context_diff(fromlines, tolines, fromfile, tofile, fromdate, todate, n=n)
-  
+
   difflines = [line for line in diff]
   sys.stdout.writelines(difflines)
 
-  if difflines : sys.exit(1)
-  else         : sys.exit(0)
+  if difflines:
+    sys.exit(1)
+  else:
+    sys.exit(0)
 
 if __name__ == '__main__':
   main()