Rework CachedRepo to use the GitDirectory class where possible

This consolidates a bunch of code paths that were previously duplicated.

This also changes the API for local cached repos to match the
function names GitDirectory uses. Note that the remote repo cache still
uses the old names, and should be fixed when time permits.

Some unit tests that use the CachedRepo module required a bit of
inelegant monkey-patching in order that they continue to work. A better
way to do this would be with the 'mock' library (which would need to be
added to Baserock 'build' and 'devel' systems before we could use it).

1 files changed, 31 insertions, 13 deletions

diff --git a/morphlib/gitdir.py b/morphlib/gitdir.py
index ed71e422..cd395228 100644
--- a/morphlib/gitdir.py
+++ b/morphlib/gitdir.py
@@ -460,8 +460,7 @@ class GitDirectory(object):
 
     def get_blob_contents(self, blob_id): # pragma: no cover
         '''Get file contents from git by ID'''
-        return morphlib.git.gitcmd(self._runcmd, 'cat-file', 'blob',
-                                   blob_id)
+        return morphlib.git.gitcmd(self._runcmd, 'cat-file', 'blob', blob_id)
 
     def get_commit_contents(self, commit_id): # pragma: no cover
         '''Get commit contents from git by ID'''
@@ -501,15 +500,16 @@ class GitDirectory(object):
         '''
         return Remote(self, *args, **kwargs)
 
-    def update_remotes(self): # pragma: no cover
+    def update_remotes(self, echo_stderr=False): # pragma: no cover
         '''Run "git remote update --prune".'''
-        morphlib.git.gitcmd(self._runcmd, 'remote', 'update', '--prune')
+        morphlib.git.gitcmd(self._runcmd, 'remote', 'update', '--prune',
+                            echo_stderr=echo_stderr)
 
     def is_bare(self):
         '''Determine whether the repository has no work tree (is bare)'''
         return self.get_config('core.bare') == 'true'
 
-    def list_files(self, ref=None):
+    def list_files(self, ref=None, recurse=True):
         '''Return an iterable of the files in the repository.
 
         If `ref` is specified, list files at that ref, otherwise
@@ -522,9 +522,9 @@ class GitDirectory(object):
         if ref is None and self.is_bare():
             raise NoWorkingTreeError(self)
         if ref is None:
-            return self._list_files_in_work_tree()
+            return self._list_files_in_work_tree(recurse)
         else:
-            return self._list_files_in_ref(ref)
+            return self._list_files_in_ref(ref, recurse)
 
     def _rev_parse(self, ref):
         try:
@@ -575,31 +575,49 @@ class GitDirectory(object):
         except InvalidRefError:
             return False
 
-    def _list_files_in_work_tree(self):
+    def _list_files_in_work_tree(self, recurse=True):
         for dirpath, subdirs, filenames in os.walk(self.dirname):
-            if dirpath == self.dirname and '.git' in subdirs:
+            if not recurse:  # pragma: no cover
+                subdirs[:] = []
+            elif dirpath == self.dirname and '.git' in subdirs:
                 subdirs.remove('.git')
             for filename in filenames:
                 filepath = os.path.join(dirpath, filename)
                 yield os.path.relpath(filepath, start=self.dirname)
 
-    def _list_files_in_ref(self, ref):
+    def _list_files_in_ref(self, ref, recurse=True):
         tree = self.resolve_ref_to_tree(ref)
-        output = morphlib.git.gitcmd(self._runcmd, 'ls-tree',
-                                     '--name-only', '-rz', tree)
+
+        command = ['ls-tree', '--name-only', '-z']
+        if recurse:
+            command.append('-r')
+        command.append(tree)
+
+        output = morphlib.git.gitcmd(self._runcmd, *command)
         # ls-tree appends \0 instead of interspersing, so we need to
         # strip the trailing \0 before splitting
         paths = output.strip('\0').split('\0')
         return paths
 
     def read_file(self, filename, ref=None):
+        '''Attempts to read a file, from the working tree or a given ref.
+
+        Raises an InvalidRefError if the ref is not found in the repository.
+        Raises an IOError if the requested file is not found in the ref.
+
+        '''
+
         if ref is None and self.is_bare():
             raise NoWorkingTreeError(self)
         if ref is None:
             with open(os.path.join(self.dirname, filename)) as f:
                 return f.read()
         tree = self.resolve_ref_to_tree(ref)
-        return self.get_file_from_ref(tree, filename)
+        try:
+            return self.get_file_from_ref(tree, filename)
+        except cliapp.AppException:
+            raise IOError('File %s does not exist in ref %s of repo %s' %
+                          (filename, ref, self))
 
     def is_symlink(self, filename, ref=None):
         if ref is None and self.is_bare():