NF: datalad tree command

changelog.d/20220824_085736_michael.hanke_nf_tree.md

@@ -0,0 +1,11 @@
+### 💫 Enhancements and new features
+
+- New `tree` command for traversing a directory hierarchy.
+  Like the UNIX equivalent, it can visualize a directory tree.
+  Additionally, it annotates the output with DataLad-related
+  information, like the location of dataset, and their nesting
+  depth. Besides visualization, `tree` also reports structured
+  data in the form of result records that enable other applications
+  to use `tree` for gathering data from the file system.
+  Fixes https://github.com/datalad/datalad-next/issues/78 via
+  https://github.com/datalad/datalad-next/pull/92 (by @catetrai)

datalad_next/__init__.py

@@ -28,6 +28,14 @@
             # not pick it up, due to the dashes in the name
             'create-sibling-webdav',
         ),
+        (
+            # importable module that contains the command implementation
+            'datalad_next.tree',
+            # name of the command class implementation in above module
+            'TreeCommand',
+            # command name (differs from lowercase command class name)
+            'tree'
+        )
     ]
 )
 

datalad_next/conftest.py

@@ -1 +1 @@
-from datalad.conftest import setup_package
+from datalad.conftest import setup_package

datalad_next/tests/test_register.py

@@ -2,3 +2,4 @@
 def test_register():
     import datalad.api as da
     assert hasattr(da, 'credentials')
+    assert hasattr(da, 'tree')