MorphSet: Add method for changing refs en-masse

This is used to change all the refs of the morphologies in the root
repository to point to the system branch instead.

2 files changed, 34 insertions, 0 deletions

diff --git a/morphlib/morphset.py b/morphlib/morphset.py
index dad3c834..2343cbae 100644
--- a/morphlib/morphset.py
+++ b/morphlib/morphset.py
@@ -222,6 +222,26 @@ class MorphologySet(object):
 
         return known
 
+    def repoint_refs(self, repo_url, new_ref):
+        '''Change all specs which refer to (repo, *) to (repo, new_ref).
+        
+        This is stunningly similar to change_ref, with the exception of
+        ignoring the morphology name and ref fields.
+
+        It is intended to be used before chunks are petrified
+
+        '''
+        def wanted_spec(m, kind, spec):
+            return spec['repo'] == repo_url
+
+        def process_spec(m, kind, spec):
+            if 'unpetrify-ref' not in spec:
+                spec['unpetrify-ref'] = spec['ref']
+            spec['ref'] = new_ref
+            return True
+
+        self._traverse_specs(process_spec, wanted_spec)
+
     def petrify_chunks(self, resolutions):
         '''Update _every_ chunk's ref to the value resolved in resolutions.
 
diff --git a/morphlib/morphset_tests.py b/morphlib/morphset_tests.py
index baa3e103..fa8fa030 100644
--- a/morphlib/morphset_tests.py
+++ b/morphlib/morphset_tests.py
@@ -192,6 +192,20 @@ class MorphologySetTests(unittest.TestCase):
                          [('test:foo-chunk', 'master'),
                           ('test:morphs', 'master')])
 
+    def test_repoint_refs(self):
+        self.morphs.add_morphology(self.system)
+        self.morphs.add_morphology(self.stratum)
+        self.morphs.repoint_refs('test:morphs', 'test')
+        self.assertEqual(self.system['strata'],
+                         [
+                             {
+                                 'morph': 'foo-stratum',
+                                 'ref': 'test',
+                                 'repo': 'test:morphs',
+                                 'unpetrify-ref': 'master',
+                             }
+                         ])
+
     def test_petrify_chunks(self):
         # TODO: test petrifying a larger morphset
         self.morphs.add_morphology(self.system)