commands/update: add --rev option

dvc/command/update.py

@@ -16,7 +16,10 @@ def run(self):
         ret = 0
         for target in self.args.targets:
             try:
-                self.repo.update(target)
+                self.repo.update(
+                    target,
+                    rev=self.args.rev,
+                )
             except DvcException:
                 logger.exception("failed to update '{}'.".format(target))
                 ret = 1
@@ -35,4 +38,7 @@ def add_parser(subparsers, parent_parser):
     update_parser.add_argument(
         "targets", nargs="+", help="DVC-files to update."
     )
+    update_parser.add_argument(
+        "--rev", nargs="?", help="DVC repository git revision."
+    )
     update_parser.set_defaults(func=CmdUpdate)

dvc/dependency/base.py

@@ -29,5 +29,5 @@ class DependencyBase(object):
     IsNotFileOrDirError = DependencyIsNotFileOrDirError
     IsStageFileError = DependencyIsStageFileError
 
-    def update(self):
+    def update(self, rev):
         pass

dvc/dependency/repo.py

@@ -114,6 +114,9 @@ def download(self, to):
                 self.def_path, self.def_repo[self.PARAM_URL]
             )
 
-    def update(self):
-        with self._make_repo(rev_lock=None) as repo:
+    def update(self, rev):
+        if not rev:
+            rev = self.def_repo.get("rev")
+
+        with self._make_repo(rev=rev, rev_lock=None) as repo:
             self.def_repo[self.PARAM_REV_LOCK] = repo.scm.get_rev()

dvc/exceptions.py

@@ -353,3 +353,10 @@ def __init__(self, path, repo):
             " neighther as an output nor a git-handled file."
         )
         super(PathMissingError, self).__init__(msg.format(path, repo))
+
+
+class UpdateWithRevNotPossibleError(DvcException):
+    def __init__(self):
+        super(UpdateWithRevNotPossibleError, self).__init__(
+            "Revision option (--rev) is not a feature of non-Git sources."
+        )

dvc/repo/update.py

@@ -1,11 +1,17 @@
+from dvc.exceptions import UpdateWithRevNotPossibleError
+
 from . import locked
 
 
 @locked
-def update(self, target):
+def update(self, target, rev=None):
     from dvc.stage import Stage
 
     stage = Stage.load(self, target)
-    stage.update()
+
+    if not stage.is_repo_import and rev:
+        raise UpdateWithRevNotPossibleError()
+
+    stage.update(rev=rev)
 
     stage.dump()

dvc/stage.py

@@ -395,11 +395,11 @@ def reproduce(self, interactive=False, **kwargs):
 
         return self
 
-    def update(self):
+    def update(self, rev=None):
         if not self.is_repo_import and not self.is_import:
             raise StageUpdateError(self.relpath)
 
-        self.deps[0].update()
+        self.deps[0].update(rev)
         locked = self.locked
         self.locked = False
         try:

tests/func/test_update.py

@@ -1,7 +1,9 @@
 import filecmp
 import os
 import shutil
+import pytest
 
+from dvc.exceptions import UpdateWithRevNotPossibleError
 from dvc.external_repo import clean_repos
 from dvc.repo import Repo
 
@@ -72,3 +74,48 @@ def test_update_import_url(repo_dir, dvc_repo):
     assert os.path.exists(dst)
     assert os.path.isfile(dst)
     assert filecmp.cmp(src, dst, shallow=False)
+
+
+def test_update_rev(dvc_repo, erepo):
+    src = "version"
+    dst = src
+
+    stage = dvc_repo.imp(erepo.root_dir, src, dst, rev="branch")
+
+    # update data
+    repo = Repo(erepo.root_dir)
+
+    saved_dir = os.getcwd()
+    os.chdir(erepo.root_dir)
+
+    repo.scm.checkout("master")
+    os.unlink("version")
+    erepo.create("version", "updated")
+    repo.add("version")
+    repo.scm.add([".gitignore", "version.dvc"])
+    repo.scm.commit("updated")
+
+    repo.scm.close()
+
+    os.chdir(saved_dir)
+
+    # Caching in external repos doesn't see upstream updates within single
+    # cli call, so we need to clean the caches to see the changes.
+    clean_repos()
+
+    dvc_repo.update(stage.path, "master")
+
+    with open(dst, "r+") as fobj:
+        assert fobj.read() == "updated"
+
+
+def test_update_rev_non_git_failure(repo_dir, dvc_repo):
+    src = "file"
+    dst = src + "_imported"
+
+    shutil.copyfile(repo_dir.FOO, src)
+
+    stage = dvc_repo.imp_url(src, dst)
+
+    with pytest.raises(UpdateWithRevNotPossibleError):
+        dvc_repo.update(stage.path, rev="dev")

tests/unit/command/test_update.py

@@ -1,15 +1,35 @@
+import logging
+
 from dvc.cli import parse_args
 from dvc.command.update import CmdUpdate
+from dvc.exceptions import UpdateWithRevNotPossibleError
 
 
 def test_update(dvc_repo, mocker):
     targets = ["target1", "target2", "target3"]
-    cli_args = parse_args(["update"] + targets)
+    cli_args = parse_args(["update", "--rev", "develop"] + targets)
     assert cli_args.func == CmdUpdate
     cmd = cli_args.func(cli_args)
     m = mocker.patch("dvc.repo.Repo.update")
 
     assert cmd.run() == 0
 
-    calls = [mocker.call(target) for target in targets]
+    calls = [mocker.call(target, rev="develop") for target in targets]
     m.assert_has_calls(calls)
+
+
+def test_update_rev_failed(mocker, caplog, dvc_repo):
+    targets = ["target1", "target2", "target3"]
+    cli_args = parse_args(["update", "--rev", "develop"] + targets)
+    assert cli_args.func == CmdUpdate
+
+    cmd = cli_args.func(cli_args)
+    with mocker.patch.object(
+        cmd.repo, "update", side_effect=UpdateWithRevNotPossibleError()
+    ):
+        with caplog.at_level(logging.ERROR, logger="dvc"):
+            assert cmd.run() == 1
+            expected_error = (
+                "Revision option (--rev) is not a feature of non-Git sources."
+            )
+            assert expected_error in caplog.text