staging: don't use move

dvc/fs/utils.py

@@ -14,27 +14,48 @@ if TYPE_CHECKING:
 logger = logging.getLogger(__name__)
 
 
+def _link(
+    from_fs: "BaseFileSystem",
+    from_info: "AnyPath",
+    to_fs: "BaseFileSystem",
+    to_info: "DvcPath",
+    hardlink: bool = False,
+) -> None:
+    if not isinstance(from_fs, type(to_fs)):
+        raise OSError(errno.EXDEV, "can't link across filesystems")
+
+    links = ["reflink"] + ["hardlink"] if hardlink else []
+    while links:
+        link = links.pop(0)
+        try:
+            func = getattr(to_fs, link)
+        except AttributeError:
+            continue
+
+        try:
+            return func(from_info, to_info)
+        except RemoteActionNotImplemented:
+            continue
+        except OSError as exc:
+            if exc.errno not in [errno.EXDEV, errno.ENOTSUP]:
+                raise
+
+    raise OSError(errno.ENOTSUP, "reflink and hardlink are not supported")
+
+
 def transfer(
     from_fs: "BaseFileSystem",
     from_info: "AnyPath",
     to_fs: "BaseFileSystem",
     to_info: "DvcPath",
-    move: bool = False,
+    hardlink: bool = False,
 ) -> None:
-    same_fs = isinstance(from_fs, type(to_fs))
-    use_move = same_fs and move
     try:
-        if use_move:
-            return to_fs.move(from_info, to_info)
-
-        if same_fs:
-            try:
-                return from_fs.reflink(from_info, to_info)
-            except RemoteActionNotImplemented:
-                pass
-            except OSError as exc:
-                if exc.errno not in [errno.EXDEV, errno.ENOTSUP]:
-                    raise
+        try:
+            return _link(from_fs, from_info, to_fs, to_info, hardlink=hardlink)
+        except OSError as exc:
+            if exc.errno not in [errno.EXDEV, errno.ENOTSUP]:
+                raise
 
         if isinstance(from_fs, LocalFileSystem):
             if not isinstance(from_info, from_fs.PATH_CLS):
@@ -61,8 +82,6 @@ def transfer(
             and isinstance(exc.__context__, FileExistsError)
         ):
             logger.debug("'%s' file already exists, skipping", to_info)
-            if use_move:
-                from_fs.remove(from_info)
             return None
 
         raise

dvc/objects/db/base.py

@@ -81,13 +81,17 @@ class ObjectDB:
         from_info: "AnyPath",
         to_info: "DvcPath",
         _hash_info: "HashInfo",
-        move: bool = False,
+        hardlink: bool = False,
     ):
         from dvc import fs
 
         self.makedirs(to_info.parent)
         return fs.utils.transfer(
-            from_fs, from_info, self.fs, to_info, move=move
+            from_fs,
+            from_info,
+            self.fs,
+            to_info,
+            hardlink=hardlink,
         )
 
     def add(
@@ -95,7 +99,7 @@ class ObjectDB:
         path_info: "AnyPath",
         fs: "BaseFileSystem",
         hash_info: "HashInfo",
-        move: bool = True,
+        hardlink: bool = False,
         verify: Optional[bool] = None,
     ):
         if self.read_only:
@@ -110,7 +114,7 @@ class ObjectDB:
             pass
 
         cache_info = self.hash_to_path_info(hash_info.value)
-        self._add_file(fs, path_info, cache_info, hash_info, move=move)
+        self._add_file(fs, path_info, cache_info, hash_info, hardlink=hardlink)
 
         try:
             if verify:

dvc/objects/db/reference.py

@@ -58,12 +58,16 @@ class ReferenceObjectDB(ObjectDB):
         from_info: "AnyPath",
         to_info: "DvcPath",
         hash_info: "HashInfo",
-        move: bool = False,
+        hardlink: bool = False,
     ):
         self.makedirs(to_info.parent)
         if hash_info.isdir:
             return super()._add_file(
-                from_fs, from_info, to_info, hash_info, move
+                from_fs,
+                from_info,
+                to_info,
+                hash_info,
+                hardlink=hardlink,
             )
         ref_file = ReferenceHashFile(from_info, from_fs, hash_info)
         self._obj_cache[hash_info] = ref_file

dvc/objects/stage.py

@@ -88,7 +88,7 @@ def _stage_file(path_info, fs, name, odb=None, upload_odb=None, dry_run=False):
     if dry_run:
         obj = HashFile(path_info, fs, hash_info)
     else:
-        odb.add(path_info, fs, hash_info, move=False)
+        odb.add(path_info, fs, hash_info, hardlink=False)
         obj = odb.get(hash_info)
 
     return path_info, meta, obj
@@ -175,7 +175,7 @@ def _stage_tree(path_info, fs, fs_info, name, odb=None, **kwargs):
             path_info, fs
         )
     tree.digest(hash_info=hash_info)
-    odb.add(tree.path_info, tree.fs, tree.hash_info, move=True)
+    odb.add(tree.path_info, tree.fs, tree.hash_info, hardlink=False)
     raw = odb.get(tree.hash_info)
     # cleanup unneeded memfs tmpfile and return tree based on the
     # ODB fs/path

dvc/objects/transfer.py

@@ -133,7 +133,7 @@ def transfer(
     obj_ids: Iterable["HashInfo"],
     jobs: Optional[int] = None,
     verify: bool = False,
-    move: bool = False,
+    hardlink: bool = False,
     **kwargs,
 ) -> int:
     """Transfer (copy) the specified objects from one ODB to another.
@@ -157,7 +157,11 @@ def transfer(
     def func(hash_info: "HashInfo") -> None:
         obj = src.get(hash_info)
         return dest.add(
-            obj.path_info, obj.fs, obj.hash_info, verify=verify, move=move
+            obj.path_info,
+            obj.fs,
+            obj.hash_info,
+            verify=verify,
+            hardlink=hardlink,
         )
 
     total = len(status.new)

dvc/output.py

@@ -600,7 +600,7 @@ class Output:
                     self.odb,
                     {obj.hash_info},
                     shallow=False,
-                    move=True,
+                    hardlink=True,
                 )
             checkout(
                 filter_info or self.path_info,
@@ -629,7 +629,7 @@ class Output:
             self.odb,
             {save_obj.hash_info} | {oid for _, _, oid in save_obj},
             shallow=True,
-            move=True,
+            hardlink=True,
         )
         return checkout_obj
 
@@ -826,7 +826,7 @@ class Output:
             odb,
             {obj.hash_info},
             jobs=jobs,
-            move=upload,
+            hardlink=False,
             shallow=False,
         )
 

tests/func/test_add.py

@@ -496,27 +496,27 @@ def test_should_update_state_entry_for_directory_after_add(
 
     ret = main(["add", "data"])
     assert ret == 0
-    assert file_md5_counter.mock.call_count == 4
+    assert file_md5_counter.mock.call_count == 3
 
     ret = main(["status"])
     assert ret == 0
-    assert file_md5_counter.mock.call_count == 4
+    assert file_md5_counter.mock.call_count == 3
 
     ls = "dir" if os.name == "nt" else "ls"
     ret = main(
         ["run", "--single-stage", "-d", "data", "{} {}".format(ls, "data")]
     )
     assert ret == 0
-    assert file_md5_counter.mock.call_count == 4
+    assert file_md5_counter.mock.call_count == 3
 
     os.rename("data", "data" + ".back")
     ret = main(["checkout"])
     assert ret == 0
-    assert file_md5_counter.mock.call_count == 4
+    assert file_md5_counter.mock.call_count == 3
 
     ret = main(["status"])
     assert ret == 0
-    assert file_md5_counter.mock.call_count == 4
+    assert file_md5_counter.mock.call_count == 3
 
 
 class TestAddCommit(TestDvc):
@@ -537,15 +537,15 @@ def test_should_collect_dir_cache_only_once(mocker, tmp_dir, dvc):
     counter = mocker.spy(dvc_module.objects.stage, "_stage_tree")
     ret = main(["add", "data"])
     assert ret == 0
-    assert counter.mock.call_count == 2
+    assert counter.mock.call_count == 1
 
     ret = main(["status"])
     assert ret == 0
-    assert counter.mock.call_count == 2
+    assert counter.mock.call_count == 1
 
     ret = main(["status"])
     assert ret == 0
-    assert counter.mock.call_count == 2
+    assert counter.mock.call_count == 1
 
 
 class TestShouldPlaceStageInDataDirIfRepositoryBelowSymlink(TestDvc):
@@ -964,7 +964,7 @@ def test_add_with_cache_link_error(tmp_dir, dvc, mocker, capsys):
     err = capsys.readouterr()[1]
     assert "reconfigure cache types" in err
 
-    assert not (tmp_dir / "foo").exists()
+    assert (tmp_dir / "foo").exists()
     assert (tmp_dir / "foo.dvc").exists()
     assert (tmp_dir / ".dvc" / "cache").read_text() == {
         "ac": {"bd18db4cc2f85cedef654fccc4a4d8": "foo"}

tests/func/test_external_repo.py

@@ -216,7 +216,7 @@ def test_subrepos_are_ignored(tmp_dir, erepo_dir):
             repo.odb.local,
             {obj.hash_info},
             shallow=False,
-            move=True,
+            hardlink=True,
         )
         assert set(cache_dir.glob("??/*")) == {
             cache_dir / "e1" / "d9e8eae5374860ae025ec84cfd85c7.dir",

tests/unit/objects/db/test_local.py

@@ -103,10 +103,9 @@ def test_staging_file(tmp_dir, dvc):
         check(local_odb, obj)
     check(staging_odb, obj)
 
-    transfer(staging_odb, local_odb, {obj.hash_info}, move=True)
+    transfer(staging_odb, local_odb, {obj.hash_info}, hardlink=True)
     check(local_odb, obj)
-    with pytest.raises(FileNotFoundError):
-        check(staging_odb, obj)
+    check(staging_odb, obj)
 
     path_info = local_odb.hash_to_path_info(obj.hash_info.value)
     assert fs.exists(path_info)
@@ -130,10 +129,11 @@ def test_staging_dir(tmp_dir, dvc):
         check(local_odb, obj)
     check(staging_odb, obj)
 
-    transfer(staging_odb, local_odb, {obj.hash_info}, shallow=False, move=True)
+    transfer(
+        staging_odb, local_odb, {obj.hash_info}, shallow=False, hardlink=True
+    )
     check(local_odb, obj)
-    with pytest.raises(FileNotFoundError):
-        check(staging_odb, obj)
+    check(staging_odb, obj)
 
     path_info = local_odb.hash_to_path_info(obj.hash_info.value)
     assert fs.exists(path_info)