pacman: fix package state detection (#51311)

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

@@ -171,11 +171,20 @@ def get_version(pacman_output):
     """Take pacman -Qi or pacman -Si output and get the Version"""
     lines = pacman_output.split('\n')
     for line in lines:
-        if 'Version' in line:
+        if line.startswith('Version '):
             return line.split(':')[1].strip()
     return None
 
 
+def get_name(module, pacman_output):
+    """Take pacman -Qi or pacman -Si output and get the package name"""
+    lines = pacman_output.split('\n')
+    for line in lines:
+        if line.startswith('Name '):
+            return line.split(':')[1].strip()
+    module.fail_json(msg="get_name: fail to retrieve package name from pacman output")
+
+
 def query_package(module, pacman_path, name, state="present"):
     """Query the package status in both the local system and the repository. Returns a boolean to indicate if the package is installed, a second
     boolean to indicate if the package is up-to-date and a third boolean to indicate whether online information were available
@@ -186,6 +195,12 @@ def query_package(module, pacman_path, name, state="present"):
         if lrc != 0:
             # package is not installed locally
             return False, False, False
+        else:
+            # a non-zero exit code doesn't always mean the package is installed
+            # for example, if the package name queried is "provided" by another package
+            installed_name = get_name(module, lstdout)
+            if installed_name != name:
+                return False, False, False
 
         # get the version installed locally (if any)
         lversion = get_version(lstdout)