dvc.repo.tree -> dvc.scm.tree

Tree objects are used as `Repo().tree`, so it seemed logical to put them
inside `dvc/repo/tree.py`. But what is more important - `dvc.repo.Repo`
depends on `dvc.scm` and it is not convinient to use `dvc.repo.tree` in
`dvc.scm.git`.

Fix #1769

dvc/repo/__init__.py

@@ -38,7 +38,7 @@ class Repo(object):
         from dvc.data_cloud import DataCloud
         from dvc.updater import Updater
         from dvc.repo.metrics import Metrics
-        from dvc.repo.tree import WorkingTree
+        from dvc.scm.tree import WorkingTree
 
         root_dir = self.find_root(root_dir)
 

dvc/repo/brancher.py

@@ -25,7 +25,7 @@ def brancher(  # noqa: E302
     scm = self.scm
 
     if self.scm.is_dirty():
-        from dvc.repo.tree import WorkingTree
+        from dvc.scm.tree import WorkingTree
 
         self.tree = WorkingTree()
         yield "Working Tree"

dvc/scm/git/tree.py

@@ -3,7 +3,7 @@ import os
 
 from dvc.utils.compat import StringIO
 
-from dvc.repo.tree import BaseTree
+from dvc.scm.tree import BaseTree
 
 
 # see git-fast-import(1)

tests/test_repo.py

@@ -1,7 +1,7 @@
 from tests.basic_env import TestDvc
 
 from dvc.scm.git import GitTree
-from dvc.repo.tree import WorkingTree
+from dvc.scm.tree import WorkingTree
 
 
 class TestCollect(TestDvc):

tests/test_tree.py

@@ -6,7 +6,7 @@ from os.path import join
 
 from dvc.scm import SCM
 from dvc.scm.git import GitTree
-from dvc.repo.tree import WorkingTree
+from dvc.scm.tree import WorkingTree
 
 from tests.basic_env import TestDir, TestGit