refs now take repo as first argument and derive from LazyMixin to allow them to dynamically retrieve their objects

Improved way commits are returned by refs as they now use the path to be sure they always point to the ref even if it changes - previously it would use the sha intead so it would not update after being cached on the ref object

1 files changed, 41 insertions, 53 deletions

diff --git a/lib/git/refs.py b/lib/git/refs.py
index 820150d3..bc5cc005 100644
--- a/lib/git/refs.py
+++ b/lib/git/refs.py
@@ -8,16 +8,19 @@ Module containing all ref based objects
 """
 from objects.base import Object
 from objects.util import get_object_type_by_name
+from utils import LazyMixin
 
-class Ref(object):
+class Ref(LazyMixin):
 	"""
 	Represents a named reference to any object
 	"""
-	__slots__ = ("path", "object")
+	__slots__ = ("repo", "path", "object")
 	
-	def __init__(self, path, object = None):
+	def __init__(self, repo, path, object = None):
 		"""
 		Initialize this instance
+		``repo``
+			Our parent repository
 		
 		``path``
 			Path relative to the .git/ directory pointing to the ref in question, i.e.
@@ -26,8 +29,19 @@ class Ref(object):
 		``object``
 			Object instance, will be retrieved on demand if None
 		"""
+		self.repo = repo
 		self.path = path
-		self.object = object
+		if object is not None:
+			self.object = object
+		
+	def _set_cache_(self, attr):
+		if attr == "object":
+			# have to be dynamic here as we may be a tag which can point to anything
+			# it uses our path to stay dynamic
+			type_string = self.repo.git.cat_file(self.path, t=True).rstrip() 
+			self.object = get_object_type_by_name(type_string)(self.repo, self.path)
+		else:
+			super(Ref, self)._set_cache_(attr)
 		
 	def __str__(self):
 		return self.name
@@ -92,19 +106,8 @@ class Ref(object):
 
 	@classmethod
 	def _list_from_string(cls, repo, text):
-		"""
-		Parse out ref information into a list of Ref compatible objects
-
-		``repo``
-			is the Repo
-		``text``
-			is the text output from the git-for-each-ref command
-
-		Returns
-			git.Ref[]
-			
-			list of Ref objects
-		"""
+		""" Parse out ref information into a list of Ref compatible objects
+		Returns git.Ref[] list of Ref objects """
 		heads = []
 
 		for line in text.splitlines():
@@ -114,28 +117,16 @@ class Ref(object):
 
 	@classmethod
 	def _from_string(cls, repo, line):
-		"""
-		Create a new Ref instance from the given string.
-
-		``repo``
-			is the Repo
-
-		``line``
-			is the formatted ref information
-
-		Format::
-		
+		""" Create a new Ref instance from the given string.
+		Format
 			name: [a-zA-Z_/]+
 			<null byte>
 			id: [0-9A-Fa-f]{40}
-
-		Returns
-			git.Head
-		"""
+		Returns git.Head """
 		full_path, hexsha, type_name, object_size = line.split("\x00")
 		obj = get_object_type_by_name(type_name)(repo, hexsha)
 		obj.size = object_size
-		return cls(full_path, obj)
+		return cls(repo, full_path, obj)
 		
 
 class Head(Ref):
@@ -196,24 +187,7 @@ class TagRef(Ref):
 		print tagref.tag.message
 	"""
 	
-	__slots__ = "tag"
-	
-	def __init__(self, path, commit_or_tag):
-		"""
-		Initialize a newly instantiated Tag
-
-		``path``
-			is the full path to the tag
-
-		``commit_or_tag``
-			is the Commit or TagObject that this tag ref points to
-		"""
-		super(TagRef, self).__init__(path, commit_or_tag)
-		self.tag = None
-		
-		if commit_or_tag.type == "tag":
-			self.tag = commit_or_tag
-		# END tag object handling 
+	__slots__ = tuple()
 	
 	@property
 	def commit(self):
@@ -223,8 +197,22 @@ class TagRef(Ref):
 		"""
 		if self.object.type == "commit":
 			return self.object
-		# it is a tag object
-		return self.object.object
+		elif self.object.type == "tag":
+			# it is a tag object which carries the commit as an object - we can point to anything
+			return self.object.object
+		else:
+			raise ValueError( "Tag %s points to a Blob or Tree - have never seen that before" % self )  
+
+	@property
+	def tag(self):
+		"""
+		Returns
+			Tag object this tag ref points to or None in case 
+			we are a light weight tag
+		"""
+		if self.object.type == "tag":
+			return self.object
+		return None
 
 	@classmethod
 	def find_all(cls, repo, common_path = "refs/tags", **kwargs):