allow 'borg repo-list' for Borg 1.x repositories via --from-borg1

- Add --from-borg1 option to borg repo-list command.
- Add allow_v1 argument to @with_repository decorator.
- If allow_v1 is True and v1_legacy is requested, allow version 1 repositories and load Manifest with RepoObj1 object class.
- Support LegacyRemoteRepository in Manifest class.
- Add test_repo_list_from_borg1.

src/borg/archiver/_common.py

@@ -74,7 +74,14 @@ def compat_check(*, create, manifest, key, cache, compatibility, decorator_name)
 
 
 def with_repository(
-    create=False, lock=True, exclusive=False, manifest=True, cache=False, secure=True, compatibility=None
+    create=False,
+    lock=True,
+    exclusive=False,
+    manifest=True,
+    cache=False,
+    secure=True,
+    compatibility=None,
+    allow_v1=False,
 ):
     """
     Method decorator for subcommand-handling methods: do_XYZ(self, args, repository, …)
@@ -88,6 +95,7 @@ def with_repository(
     :param secure: do assert_secure after loading manifest
     :param compatibility: mandatory if not create and (manifest or cache), specifies mandatory
            feature categories to check
+    :param allow_v1: (bool) allow legacy Borg 1.x repositories
     """
     # Note: with_repository decorator does not have a "key" argument (yet?)
     compatibility = compat_check(
@@ -116,6 +124,8 @@ def with_repository(
             assert isinstance(exclusive, bool)
             lock = getattr(args, "lock", _lock)
 
+            v1_legacy = getattr(args, "v1_legacy", False) if allow_v1 else False
+
             repository = get_repository(
                 location,
                 create=create,
@@ -123,18 +133,25 @@ def with_repository(
                 lock_wait=self.lock_wait,
                 lock=lock,
                 args=args,
-                v1_legacy=False,
+                v1_legacy=v1_legacy,
             )
 
             with repository:
-                if repository.version not in (4,):
+                acceptable_versions = (1,) if v1_legacy else (4,)
+                if repository.version not in acceptable_versions:
                     raise Error(
-                        f"This borg version only accepts version 4 repos for -r/--repo, "
-                        f"but not version {repository.version}. "
+                        f"This borg version only accepts version {' or '.join(str(v) for v in acceptable_versions)} "
+                        f"repos for -r/--repo, but not version {repository.version}. "
                         f"You can use 'borg transfer' to copy archives from old to new repos."
                     )
                 if manifest or cache:
-                    manifest_ = Manifest.load(repository, compatibility, other=False)
+                    if repository.version > 1:
+                        ro_cls = RepoObj
+                    else:
+                        from ..legacy.repoobj import RepoObj1
+
+                        ro_cls = RepoObj1
+                    manifest_ = Manifest.load(repository, compatibility, other=False, ro_cls=ro_cls)
                     kwargs["manifest"] = manifest_
                     if "compression" in args:
                         manifest_.repo_objs.compressor = args.compression.compressor

src/borg/archiver/repo_list_cmd.py

@@ -14,7 +14,7 @@ logger = create_logger()
 
 
 class RepoListMixIn:
-    @with_repository(compatibility=(Manifest.Operation.READ,))
+    @with_repository(compatibility=(Manifest.Operation.READ,), allow_v1=True)
     def do_repo_list(self, args, repository, manifest):
         """List the archives contained in a repository."""
         if args.format is not None:
@@ -91,6 +91,7 @@ class RepoListMixIn:
         subparser.add_argument(
             "--short", dest="short", action="store_true", help="only print the archive IDs, nothing else"
         )
+        subparser.add_argument("--from-borg1", dest="v1_legacy", action="store_true", help="repository is Borg 1.x")
         subparser.add_argument(
             "--format",
             metavar="FORMAT",

src/borg/manifest.py

@@ -448,9 +448,10 @@ class Manifest:
 
     def __init__(self, key, repository, item_keys=None, ro_cls=RepoObj):
         from .legacy.repository import LegacyRepository
+        from .legacy.remote import LegacyRemoteRepository
         from .legacy.archives import LegacyArchives
 
-        if isinstance(repository, LegacyRepository):
+        if isinstance(repository, (LegacyRepository, LegacyRemoteRepository)):
             self.archives: ArchivesInterface = LegacyArchives(repository, self)
         else:
             self.archives: ArchivesInterface = Archives(repository, self)

src/borg/testsuite/archiver/repo_list_cmd_test.py

@@ -1,6 +1,8 @@
 import json
 import os
 
+import pytest
+
 from ...constants import *  # NOQA
 from . import cmd, checkts, create_regular_file, generate_archiver_tests, RK_ENCRYPTION
 from .prune_cmd_test import _create_archive_ts
@@ -169,3 +171,29 @@ def test_repo_list_deleted(archivers, request, backup_files):
     assert "normal2" not in output
     assert "deleted1" in output
     assert "deleted2" in output
+
+
+def test_repo_list_from_borg1(archivers, request, monkeypatch):
+    archiver = request.getfixturevalue(archivers)
+    if archiver.get_kind() in ["remote", "binary"]:
+        pytest.skip("only works locally")
+
+    import tarfile
+
+    repo12_tar = os.path.join(os.path.dirname(__file__), "repo12.tar.gz")
+    original_location = archiver.repository_location
+    extract_dir = f"{original_location}1"
+    os.makedirs(extract_dir)
+    with tarfile.open(repo12_tar) as tf:
+        tf.extractall(extract_dir)
+
+    monkeypatch.setenv("BORG_PASSPHRASE", "waytooeasyonlyfortests")
+    monkeypatch.setenv("BORG_TESTONLY_WEAKEN_KDF", "0")
+
+    # Set repository location to the extracted Borg 1.x repository
+    archiver.repository_location = extract_dir
+    archiver.repository_path = extract_dir
+
+    output = cmd(archiver, "repo-list", "--from-borg1")
+    assert "archive1" in output
+    assert "archive2" in output