Add support for default branch detection (GH-254)

* 🎨 Make config store default branch

* 📝 Document default_branch in README

* ✅🐛 Add test for default_branch config option

Author: webknjaz

cherry_picker/cherry_picker/cherry_picker.py

@@ -22,7 +22,8 @@
     'team': 'python',
     'repo': 'cpython',
     'check_sha': '7f777ed95a19224294949e1b4ce56bbffcb1fe9f',
-    'fix_commit_msg': True
+    'fix_commit_msg': True,
+    'default_branch': 'master',
 })
 
 
@@ -135,9 +136,10 @@ def get_commit_message(self, commit_sha):
         else:
             return message
 
-    def checkout_master(self):
-        """ git checkout master """
-        cmd = ['git', 'checkout', 'master']
+    def checkout_default_branch(self):
+        """ git checkout default branch """
+
+        cmd = 'git', 'checkout', self.config['default_branch']
         self.run_cmd(cmd)
 
     def status(self):
@@ -256,7 +258,7 @@ def delete_branch(self, branch):
         self.run_cmd(cmd)
 
     def cleanup_branch(self, branch):
-        self.checkout_master()
+        self.checkout_default_branch()
         try:
             self.delete_branch(branch)
         except subprocess.CalledProcessError:

cherry_picker/cherry_picker/test.py

@@ -194,22 +194,26 @@ def test_find_config_not_found(tmpdir, cd):
     assert find_config() is None
 
 
-def test_load_config(tmpdir, cd):
+def test_load_full_config(tmpdir, cd):
     cd(tmpdir)
     subprocess.run('git init .'.split(), check=True)
     cfg = tmpdir.join('.cherry_picker.toml')
     cfg.write('''\
     team = "python"
     repo = "core-workfolow"
     check_sha = "5f007046b5d4766f971272a0cc99f8461215c1ec"
+    default_branch = "devel"
     ''')
     cfg = load_config(None)
     assert cfg == {'check_sha': '5f007046b5d4766f971272a0cc99f8461215c1ec',
                    'repo': 'core-workfolow',
-                   'team': 'python'}
+                   'team': 'python',
+                   'fix_commit_msg': True,
+                   'default_branch': 'devel',
+                   }
 
 
-def test_load_config(tmpdir, cd):
+def test_load_partial_config(tmpdir, cd):
     cfg = tmpdir.join('.cherry_picker.toml')
     cfg.write('''\
     repo = "core-workfolow"
@@ -218,7 +222,9 @@ def test_load_config(tmpdir, cd):
     assert cfg == {'check_sha': '7f777ed95a19224294949e1b4ce56bbffcb1fe9f',
                    'repo': 'core-workfolow',
                    'team': 'python',
-                   'fix_commit_msg': True}
+                   'fix_commit_msg': True,
+                   'default_branch': 'master',
+                   }
 
 
 def test_normalize_long_commit_message():

cherry_picker/readme.rst

@@ -110,6 +110,7 @@ Configuration file example::
    repo = "aiohttp"
    check_sha = "f382b5ffc445e45a110734f5396728da7914aeb6"
    fix_commit_msg = false
+   default_branch = "devel"
 
 
 Available config options::
@@ -133,14 +134,18 @@ Available config options::
                    on pull-request xxxx.
                    For projects using GitHub Issues, this option can be disabled.
 
+   repo            Project's default branch name,
+                   e.g "devel" for https://github.com/ansible/ansible
+                   ("master" by default)
+
 
 To customize the tool for used by other project:
 
 1. Create a file called ``.cherry_picker.toml`` in the project's root
    folder (alongside with ``.git`` folder).
 
-2. Add ``team``, ``repo``, ``fix_commit_msg`` and ``check_sha``
-   config values as described above.
+2. Add ``team``, ``repo``, ``fix_commit_msg``, ``check_sha`` and
+   ``default_branch`` config values as described above.
 
 3. Use ``git add .cherry_picker.toml`` / ``git commit`` to add the config
    into ``git``.