Add support for pip list format=columns (#21990)

* Use 'pip list --format=freeze' to simplify output code parse

lib/ansible/modules/packaging/language/pip.py

@@ -250,7 +250,7 @@ def _get_full_name(name, version=None):
 def _get_packages(module, pip, chdir):
     '''Return results of pip command to get packages.'''
     # Try 'pip list' command first.
-    command = '%s list' % pip
+    command = '%s list --format=freeze' % pip
     lang_env = dict(LANG='C', LC_ALL='C', LC_MESSAGES='C')
     rc, out, err = module.run_command(command, cwd=chdir, environ_update=lang_env)
 
@@ -267,19 +267,8 @@ def _get_packages(module, pip, chdir):
 def _is_present(name, version, installed_pkgs, pkg_command):
     '''Return whether or not package is installed.'''
     for pkg in installed_pkgs:
-        # Package listing will be different depending on which pip
-        # command was used ('pip list' vs. 'pip freeze').
-        if 'list' in pkg_command:
-            pkg = pkg.replace('(', '').replace(')', '')
-            if ',' in pkg:
-                pkg_name, pkg_version, _ = pkg.replace(',', '').split(' ')
-            else:
-                pkg_name, pkg_version = pkg.split(' ')
-        elif 'freeze' in pkg_command:
-            if '==' in pkg:
-                pkg_name, pkg_version = pkg.split('==')
-            else:
-                continue
+        if '==' in pkg:
+            pkg_name, pkg_version = pkg.split('==')
         else:
             continue