Generalized custom reference creation down to SymbolicReference level. 'Reference' implementation now shares all the code from the SymbolicReference base. This implementation allows to create any reference you'd like without requireing git calls

Author: Byron

lib/git/refs.py

@@ -20,6 +20,8 @@ class SymbolicReference(object):
 	A typical example for a symbolic reference is HEAD.
 	"""
 	__slots__ = ("repo", "path")
+	_common_path_default = ""
+	_id_attribute_ = "name"
 
 	def __init__(self, repo, path):
 		self.repo = repo
@@ -231,6 +233,79 @@ def from_path(cls, repo, path):
 			return SymbolicReference(repo, path)
 
 		raise ValueError("Could not find symbolic reference type suitable to handle path %r" % path)
+
+	@classmethod
+	def _to_full_path(cls, repo, path):
+		full_ref_path = path
+		if not cls._common_path_default:
+			return full_ref_path
+		if not path.startswith(cls._common_path_default+"/"):
+			full_ref_path = '%s/%s' % (cls._common_path_default, path)
+		return full_ref_path
+	
+	@classmethod
+	def delete(cls, repo, path):
+		"""Delete the reference at the given path
+		
+		``repo``
+			Repository to delete the reference from
+		
+		``path``
+			Short or full path pointing to the reference, i.e. refs/myreference
+			or just "myreference", hence 'refs/' is implied.
+		"""
+		full_ref_path = cls._to_full_path(repo, path)
+		abs_path = os.path.join(repo.path, full_ref_path)
+		if os.path.exists(abs_path):
+			os.remove(abs_path)
+			
+	@classmethod
+	def _create(cls, repo, path, resolve, reference, force):
+		"""internal method used to create a new symbolic reference.
+		If resolve is False,, the reference will be taken as is, creating 
+		a proper symbolic reference. Otherwise it will be resolved to the 
+		corresponding object and a detached symbolic reference will be created
+		instead"""
+		full_ref_path = cls._to_full_path(repo, path)
+		
+		abs_ref_path = os.path.join(repo.path, full_ref_path)
+		if not force and os.path.isfile(abs_ref_path):
+			raise OSError("Reference at %s does already exist" % full_ref_path)
+		
+		ref = cls(repo, full_ref_path)
+		target = reference
+		if resolve:
+			target = Object.new(repo, reference)
+		
+		ref.reference = target
+		return ref
+		
+	@classmethod
+	def create(cls, repo, path, reference='HEAD', force=False ):
+		"""
+		Create a new symbolic reference, hence a reference pointing to another 
+		reference.
+		``repo``
+			Repository to create the reference in 
+			
+		``path``
+			full path at which the new symbolic reference is supposed to be 
+			created at, i.e. "NEW_HEAD" or "symrefs/my_new_symref"
+			
+		``reference``
+			The reference to which the new symbolic reference should point to
+		
+		``force``
+			if True, force creation even if a symbolic reference with that name already exists.
+			Raise OSError otherwise
+			
+		Returns
+			Newly created symbolic Reference
+			
+		Note
+			This does not alter the current HEAD, index or Working Tree
+		"""
+		return cls._create(repo, path, False, reference, force)
 
 
 class Reference(SymbolicReference, LazyMixin, Iterable):
@@ -240,7 +315,6 @@ class Reference(SymbolicReference, LazyMixin, Iterable):
 	"""
 	__slots__ = tuple()
 	_common_path_default = "refs"
-	_id_attribute_ = "name"
 
 	def __init__(self, repo, path):
 		"""
@@ -367,13 +441,6 @@ def from_path(cls, repo, path):
 		raise ValueError("Could not find reference type suitable to handle path %r" % path)
 
 
-	@classmethod
-	def _to_full_path(cls, repo, path):
-		full_ref_path = path
-		if not path.startswith(cls._common_path_default+"/"):
-			full_ref_path = '%s/%s' % (cls._common_path_default, path)
-		return full_ref_path
-	
 	@classmethod
 	def create(cls, repo, path, commit='HEAD', force=False ):
 		"""
@@ -400,33 +467,7 @@ def create(cls, repo, path, commit='HEAD', force=False ):
 		Note
 			This does not alter the current HEAD, index or Working Tree
 		"""
-		full_ref_path = cls._to_full_path(repo, path)
-		
-		abs_ref_path = os.path.join(repo.path, full_ref_path)
-		if not force and os.path.isfile(abs_ref_path):
-			raise OSError("Reference at %s does already exist" % full_ref_path)
-			
-		obj = Object.new(repo, commit)
-		ref = cls(repo, full_ref_path)
-		ref.reference = obj
-		
-		return ref
-		
-	@classmethod
-	def delete(cls, repo, path):
-		"""Delete the reference at the given path
-		
-		``repo``
-			Repository to delete the reference from
-		
-		``path``
-			Short or full path pointing to the reference, i.e. refs/myreference
-			or just "myreference", hence 'refs/' is implied.
-		"""
-		full_ref_path = cls._to_full_path(repo, path)
-		abs_path = os.path.join(repo.path, full_ref_path)
-		if os.path.exists(abs_path):
-			os.remove(abs_path)
+		return cls._create(repo, path, True, commit, force)
 
 
 class HEAD(SymbolicReference):

test/git/test_refs.py

@@ -239,17 +239,31 @@ def test_head_reset(self, rw_repo):
 		full_ref = 'refs/%s' % partial_ref
 		ref = Reference.create(rw_repo, partial_ref)
 		assert ref.path == full_ref
+		assert ref.object == rw_repo.head.commit
 
 		self.failUnlessRaises(OSError, Reference.create, rw_repo, full_ref)
 		Reference.delete(rw_repo, full_ref)
 
 		# recreate the reference using a full_ref
 		ref = Reference.create(rw_repo, full_ref)
 		assert ref.path == full_ref
+		assert ref.object == rw_repo.head.commit
 
 		# recreate using force
 		ref = Reference.create(rw_repo, partial_ref, 'HEAD~1', force=True)
 		assert ref.path == full_ref
+		assert ref.object == rw_repo.head.commit.parents[0]
+		
+		# create symbolic refs
+		symref_path = "symrefs/sym"
+		symref = SymbolicReference.create(rw_repo, symref_path, cur_head.reference)
+		assert symref.path == symref_path
+		assert symref.reference == cur_head.reference
+		
+		self.failUnlessRaises(OSError, SymbolicReference.create, rw_repo, symref_path, cur_head.reference)
+		SymbolicReference.delete(rw_repo, symref_path)
+		# would raise if the symref wouldn't have been deleted
+		symref = SymbolicReference.create(rw_repo, symref_path, cur_head.reference)
 
 		# test symbolic references which are not at default locations like HEAD
 		# or FETCH_HEAD - they may also be at spots in refs of course