fixed issue with empty string 'packages'

also cleaned up unused imports/vars
fixes #25582

lib/ansible/modules/packaging/os/pacman.py

@@ -143,10 +143,7 @@ EXAMPLES = '''
     force: yes
 '''
 
-import shlex
-import os
 import re
-import sys
 
 def get_version(pacman_output):
     """Take pacman -Qi or pacman -Si output and get the Version"""
@@ -212,8 +209,6 @@ def upgrade(module, pacman_path):
 
     if rc == 0:
         regex = re.compile('([\w-]+) ((?:\S+)-(?:\S+)) -> ((?:\S+)-(?:\S+))')
-        b = []
-        a = []
         for p in data:
             m = regex.search(p)
             packages.append(m.group(1))
@@ -378,6 +373,7 @@ def expand_package_groups(module, pacman_path, pkgs):
     expanded = []
 
     for pkg in pkgs:
+        if pkg: # avoid empty strings
             cmd = "%s -Sgq %s" % (pacman_path, pkg)
             rc, stdout, stderr = module.run_command(cmd, check_rc=False)
 
@@ -432,7 +428,9 @@ def main():
 
         pkg_files = []
         for i, pkg in enumerate(pkgs):
-            if re.match(".*\.pkg\.tar(\.(gz|bz2|xz|lrz|lzo|Z))?$", pkg):
+            if not pkg: # avoid empty strings
+                continue
+            elif re.match(".*\.pkg\.tar(\.(gz|bz2|xz|lrz|lzo|Z))?$", pkg):
                 # The package given is a filename, extract the raw pkg name from
                 # it and store the filename
                 pkg_files.append(pkg)