Install bzr hook lazily, clean up some compatibility code.

1 files changed, 11 insertions, 12 deletions

diff --git a/etckeeper-bzr/__init__.py b/etckeeper-bzr/__init__.py
index 3cf06db..61322fe 100755
--- a/etckeeper-bzr/__init__.py
+++ b/etckeeper-bzr/__init__.py
@@ -3,30 +3,29 @@
 
 """Runs etckeeper pre-commit when necessary."""
 
-import bzrlib
-from bzrlib.mutabletree import MutableTree
-from bzrlib.errors import BzrError, NotLocalUrl
+from bzrlib.errors import BzrError
 import os
-import subprocess
-
-if not (hasattr(MutableTree, "hooks") and "start_commit" in MutableTree.hooks):
-    raise "Version of Bazaar installed does not support required hooks."
 
 def etckeeper_startcommit_hook(tree):
     abspath = getattr(tree, "abspath", None)
     if abspath is None or not os.path.exists(abspath(".etckeeper")):
         # Only run the commit hook when this is an etckeeper branch
         return
+    import subprocess
     ret = subprocess.call(["etckeeper", "pre-commit", abspath(".")])
     if ret != 0:
         raise BzrError("etckeeper pre-commit failed")
 
-install_named_hook = getattr(MutableTree.hooks, 'install_named_hook', None)
-if install_named_hook is not None:
-    install_named_hook('start_commit', etckeeper_startcommit_hook, 'etckeeper')
+try:
+    from bzrlib.hooks import install_lazy_named_hook
+except ImportError:
+    from bzrlib.mutabletree import MutableTree
+    MutableTree.hooks.install_named_hook('start_commit',
+        etckeeper_startcommit_hook, 'etckeeper')
 else:
-    MutableTree.hooks.install_hook('start_commit', etckeeper_startcommit_hook)
-    MutableTree.hooks.name_hook(etckeeper_startcommit_hook, "etckeeper")
+    install_lazy_named_hook(
+        "bzrlib.mutabletree", "MutableTree.hooks",
+        'start_commit', etckeeper_startcommit_hook, 'etckeeper')
 
 if __name__ == "__main__":
     from distutils.core import setup