From fba43277e6fa8db3b604e7d658d43a929b60016e Mon Sep 17 00:00:00 2001
From: Dmitrii Pukhov <pukhovdn@yandex.ru>
Date: Tue, 26 Mar 2019 01:29:49 +0900
Subject: [PATCH 1/3] cli: add pipeline show --tree

Add option to unfold dependencies into a tree.

Fixes #1038
---
 dvc/command/pipeline.py | 39 ++++++++++++++++++++++++++++++++++++---
 requirements.txt        |  1 +
 tests/test_pipeline.py  |  4 ++++
 3 files changed, 41 insertions(+), 3 deletions(-)

diff --git a/dvc/command/pipeline.py b/dvc/command/pipeline.py
index 401ef4dcec..c594eb6bef 100644
--- a/dvc/command/pipeline.py
+++ b/dvc/command/pipeline.py
@@ -71,23 +71,46 @@ def __build_graph(self, target, commands, outs):
             else:
                 edges.append((from_stage.relpath, to_stage.relpath))
 
-        return nodes, edges
+        return nodes, edges, networkx.is_tree(G)
 
     def _show_ascii(self, target, commands, outs):
         from dvc.dagascii import draw
 
-        nodes, edges = self.__build_graph(target, commands, outs)
+        nodes, edges, _ = self.__build_graph(target, commands, outs)
 
         if not nodes:
             return
 
         draw(nodes, edges)
 
+    def _show_dependencies_tree(self, target, commands, outs):
+        from treelib import Tree
+
+        nodes, edges, is_tree = self.__build_graph(target, commands, outs)
+        if not nodes:
+            return
+        if not is_tree:
+            raise ValueError(
+                "DAG is not a tree, can not print it in tree-structure way, "
+                "please use --ascii instead"
+            )
+        tree = Tree()
+        tree.create_node(target, target)  # Root node
+        observe_list = [target]
+        while len(observe_list) > 0:
+            current_root = observe_list[0]
+            for edge in edges:
+                if edge[0] == current_root:
+                    tree.create_node(edge[1], edge[1], parent=current_root)
+                    observe_list.append(edge[1])
+            observe_list.pop(0)
+        tree.show()
+
     def __write_dot(self, target, commands, outs, filename):
         import networkx
         from networkx.drawing.nx_pydot import write_dot
 
-        _, edges = self.__build_graph(target, commands, outs)
+        _, edges, _ = self.__build_graph(target, commands, outs)
         edges = [edge[::-1] for edge in edges]
 
         simple_g = networkx.DiGraph()
@@ -111,6 +134,10 @@ def run(self, unlock=False):
                         self.args.outs,
                         self.args.dot,
                     )
+                elif self.args.tree:
+                    self._show_dependencies_tree(
+                        target, self.args.commands, self.args.outs
+                    )
                 else:
                     self._show(target, self.args.commands, self.args.outs)
             except DvcException:
@@ -185,6 +212,12 @@ def add_parser(subparsers, parent_parser):
     pipeline_show_parser.add_argument(
         "--dot", help="Write DAG in .dot format."
     )
+    pipeline_show_parser.add_argument(
+        "--tree",
+        action="store_true",
+        default=False,
+        help="Output DAG as Dependencies Tree.",
+    )
     pipeline_show_parser.add_argument(
         "targets", nargs="*", help="DVC files. 'Dvcfile' by default."
     )
diff --git a/requirements.txt b/requirements.txt
index 0eb848d45a..80c639d862 100644
--- a/requirements.txt
+++ b/requirements.txt
@@ -25,3 +25,4 @@ pydot>=1.2.4
 asciimatics>=1.10.0
 distro>=1.3.0
 appdirs>=1.4.3
+treelib>=1.5.5
diff --git a/tests/test_pipeline.py b/tests/test_pipeline.py
index f59e6afed7..0bb531454b 100644
--- a/tests/test_pipeline.py
+++ b/tests/test_pipeline.py
@@ -34,6 +34,10 @@ def test_dot(self):
         self.assertEqual(ret, 0)
         self.assertTrue(os.path.isfile(self.dotFile))
 
+    def test_tree(self):
+        ret = main(["pipeline", "show", "--tree", self.stage])
+        self.assertEqual(ret, 0)
+
     def test_ascii_commands(self):
         ret = main(["pipeline", "show", "--ascii", self.stage, "--commands"])
         self.assertEqual(ret, 0)

From 5346fc44bc6e4aeae1262bb86323d8bb69c97669 Mon Sep 17 00:00:00 2001
From: Dmitrii Pukhov <pukhovdn@yandex.ru>
Date: Tue, 26 Mar 2019 13:51:29 +0900
Subject: [PATCH 2/3] Add treelib dependency to setup.py

---
 setup.py | 1 +
 1 file changed, 1 insertion(+)

diff --git a/setup.py b/setup.py
index ce656dabd6..07fe236bac 100644
--- a/setup.py
+++ b/setup.py
@@ -22,6 +22,7 @@
     "asciimatics>=1.10.0",
     "distro>=1.3.0",
     "appdirs>=1.4.3",
+    "treelib>=1.5.5",
 ]
 
 # Extra dependencies for remote integrations

From 263dee8650aca16315a3713fb8e83919fecffa40 Mon Sep 17 00:00:00 2001
From: Dmitrii Pukhov <pukhovdn@yandex.ru>
Date: Tue, 26 Mar 2019 22:39:41 +0900
Subject: [PATCH 3/3] Replace ValueError with DvcException

---
 dvc/command/pipeline.py | 3 ++-
 1 file changed, 2 insertions(+), 1 deletion(-)

diff --git a/dvc/command/pipeline.py b/dvc/command/pipeline.py
index c594eb6bef..f6b33e9b2f 100644
--- a/dvc/command/pipeline.py
+++ b/dvc/command/pipeline.py
@@ -90,10 +90,11 @@ def _show_dependencies_tree(self, target, commands, outs):
         if not nodes:
             return
         if not is_tree:
-            raise ValueError(
+            raise DvcException(
                 "DAG is not a tree, can not print it in tree-structure way, "
                 "please use --ascii instead"
             )
+
         tree = Tree()
         tree.create_node(target, target)  # Root node
         observe_list = [target]