Don't modify passed regex_subs leading to '<_sre.SRE_Pattern..>' outputs

Author: Flamefire

easybuild/tools/filetools.py

@@ -1487,9 +1487,7 @@ def apply_regex_substitutions(paths, regex_subs, backup='.orig.eb'):
     else:
         _log.info("Applying following regex substitutions to %s: %s", paths, regex_subs)
 
-        compiled_regex_subs = []
-        for regex, subtxt in regex_subs:
-            compiled_regex_subs.append((re.compile(regex), subtxt))
+        compiled_regex_subs = [(re.compile(regex), subtxt) for (regex, subtxt) in regex_subs]
 
         for path in paths:
             try:

test/framework/filetools.py

@@ -1208,6 +1208,7 @@ def test_apply_regex_substitutions(self):
             (r"^(FC\s*=\s*).*$", r"\1${FC}"),
             (r"^(.FLAGS)\s*=\s*-O3\s-g(.*)$", r"\1 = -O2\2"),
         ]
+        regex_subs_copy = regex_subs.copy()
         ft.apply_regex_substitutions(testfile, regex_subs)
 
         expected_testtxt = '\n'.join([
@@ -1218,6 +1219,8 @@ def test_apply_regex_substitutions(self):
         ])
         new_testtxt = ft.read_file(testfile)
         self.assertEqual(new_testtxt, expected_testtxt)
+        # Must not have touched the list
+        self.assertEqual(regex_subs_copy, regex_subs)
 
         # backup file is created by default
         backup = testfile + '.orig.eb'