diff -Nur pbuilder-0.231/bash_completion.d/pbuilder new/bash_completion.d/pbuilder
--- pbuilder-0.231/bash_completion.d/pbuilder	2020-02-15 17:49:39.000000000 +0100
+++ new/bash_completion.d/pbuilder	2022-05-04 12:26:13.339197900 +0200
@@ -61,11 +61,12 @@
                 --compressprog --debootstrapopts --save-after-login --save-after-exec
                 --debootstrap' \
                 -- "$cur" ) )
-            if [[ $prev = @(--aptcache|--hookdir) ]]; then
+            if [ $prev = "--aptcache" -o $prev = "--hookdir" ]; then
                 # Optionally provide a directory
                 _filedir -d
             fi
-            if [[ $cur != -* && $command == @(--build|build) ]]; then
+            if [[ $cur != -* &&
+                ( $command = "--build" || $command = "build" ) ]]; then
                 # dsc file completion
                 _filedir "dsc"
             fi