Fix ansible-test handling of submodules.

Resolves https://github.com/ansible/ansible/issues/61550

test/lib/ansible_test/_internal/git.py

@@ -2,6 +2,8 @@
 from __future__ import (absolute_import, division, print_function)
 __metaclass__ = type
 
+import re
+
 from . import types as t
 
 from .util import (
@@ -35,6 +37,13 @@ class Git:
         cmd = ['diff', '--name-only', '--no-renames', '-z'] + args
         return self.run_git_split(cmd, '\0')
 
+    def get_submodule_paths(self):  # type: () -> t.List[str]
+        """Return a list of submodule paths recursively."""
+        cmd = ['submodule', 'status', '--recursive']
+        output = self.run_git_split(cmd, '\n')
+        submodule_paths = [re.search(r'^.[0-9a-f]+ (?P<path>[^ ]+)', line).group('path') for line in output]
+        return submodule_paths
+
     def get_file_names(self, args):
         """
         :type args: list[str]

test/lib/ansible_test/_internal/provider/source/git.py

@@ -30,6 +30,19 @@ class GitSource(SourceProvider):
         """Return the list of available content paths under the given path."""
         git = Git(path)
 
+        paths = self.__get_paths(path)
+
+        submodule_paths = git.get_submodule_paths()
+
+        for submodule_path in submodule_paths:
+            paths.extend(os.path.join(submodule_path, p) for p in self.__get_paths(os.path.join(path, submodule_path)))
+
+        return paths
+
+    @staticmethod
+    def __get_paths(path):  # type: (str) -> t.List[str]
+        """Return the list of available content paths under the given path."""
+        git = Git(path)
         paths = git.get_file_names(['--cached', '--others', '--exclude-standard'])
         deleted_paths = git.get_file_names(['--deleted'])
         paths = sorted(set(paths) - set(deleted_paths))