diff --git a/easybuild/tools/filetools.py b/easybuild/tools/filetools.py
index 80ba86be03..fb4c138197 100644
--- a/easybuild/tools/filetools.py
+++ b/easybuild/tools/filetools.py
@@ -1294,7 +1294,8 @@ def apply_regex_substitutions(path, regex_subs, backup='.orig.eb', on_missing_ma
         on_missing_match = build_option('strict')
     allowed_values = (run.ERROR, run.WARN, run.IGNORE)
     if on_missing_match not in allowed_values:
-        raise EasyBuildError('Invalid value passed to on_missing_match: %s (allowed: %s)', on_missing_match, ', '.join(allowed_values))
+        raise EasyBuildError('Invalid value passed to on_missing_match: %s (allowed: %s)',
+                             on_missing_match, ', '.join(allowed_values))
 
     # only report when in 'dry run' mode
     if build_option('extended_dry_run'):