Drop --ignore-missing-chunks option

We want robustness by default, and always.

5 files changed, 14 insertions, 25 deletions

diff --git a/obnamlib/delegator.py b/obnamlib/delegator.py
index 5065a62d..f0c6038a 100644
--- a/obnamlib/delegator.py
+++ b/obnamlib/delegator.py
@@ -198,10 +198,10 @@ class RepositoryDelegator(obnamlib.RepositoryInterface):
         client = self._lookup_client_by_generation(generation_id)
         return client.set_generation_key(generation_id.gen_number, key, value)
 
-    def remove_generation(self, generation_id, ignore_missing_chunks=False):
+    def remove_generation(self, generation_id):
         self._require_got_client_lock(generation_id.client_name)
         client = self._lookup_client_by_generation(generation_id)
-        return client.remove_generation(generation_id.gen_number, ignore_missing_chunks)
+        return client.remove_generation(generation_id.gen_number)
 
     def get_generation_chunk_ids(self, generation_id):
         client = self._lookup_client_by_generation(generation_id)
diff --git a/obnamlib/fmt_6/repo_fmt_6.py b/obnamlib/fmt_6/repo_fmt_6.py
index 3cc54426..352a73f2 100644
--- a/obnamlib/fmt_6/repo_fmt_6.py
+++ b/obnamlib/fmt_6/repo_fmt_6.py
@@ -340,7 +340,7 @@ class RepositoryFormat6(obnamlib.RepositoryInterface):
         self._raw_unlock_client(client_name)
 
     def _remove_chunks_from_removed_generations(
-            self, client_name, remove_gen_nos, ignore_missing_chunks=False):
+            self, client_name, remove_gen_nos):
 
         def find_chunkids_in_gens(gen_nos):
             chunkids = set()
@@ -358,7 +358,7 @@ class RepositoryFormat6(obnamlib.RepositoryInterface):
                     keep.append(gen_number)
             return keep
 
-        def remove_chunks(chunk_ids, ignore_missing_chunks=False):  # pragma: no cover
+        def remove_chunks(chunk_ids):  # pragma: no cover
             for chunk_id in chunk_ids:
                 try:
                     checksum = self._chunklist.get_checksum(chunk_id)
@@ -368,16 +368,17 @@ class RepositoryFormat6(obnamlib.RepositoryInterface):
                     self._remove_chunk(chunk_id)
                 else:
                     self.remove_chunk_from_indexes(chunk_id, client_name)
-                    # We can skip removal if the chunk doesn't exist
-                    skip_removal = ignore_missing_chunks and not self.has_chunk(chunk_id)
-                    if not skip_removal and not self._chunksums.chunk_is_used(checksum, chunk_id):
+                    can_be_removed = (
+                        self.has_chunk(chunk_id) and
+                        not self._chunksums.chunk_is_used(checksum, chunk_id))
+                    if can_be_removed:
                         self._remove_chunk(chunk_id)
 
         keep_gen_nos = find_gens_to_keep()
         keep_chunkids = find_chunkids_in_gens(keep_gen_nos)
         maybe_remove_chunkids = find_chunkids_in_gens(remove_gen_nos)
         remove_chunkids = maybe_remove_chunkids.difference(keep_chunkids)
-        remove_chunks(remove_chunkids, ignore_missing_chunks)
+        remove_chunks(remove_chunkids)
 
     def get_allowed_client_keys(self):
         return []
@@ -549,7 +550,7 @@ class RepositoryFormat6(obnamlib.RepositoryInterface):
         client_name, gen_number = self._unpack_gen_id(gen_id)
         return str(gen_number)
 
-    def remove_generation(self, gen_id, ignore_missing_chunks=False):
+    def remove_generation(self, gen_id):
         tracing.trace('gen_id=%s' % repr(gen_id))
         client_name, gen_number = self._unpack_gen_id(gen_id)
         self._require_client_lock(client_name)
@@ -563,8 +564,7 @@ class RepositoryFormat6(obnamlib.RepositoryInterface):
         self._forget_open_client_info_cached_generation(
             open_client_info, gen_id)
 
-        self._remove_chunks_from_removed_generations(client_name, [gen_number],
-                ignore_missing_chunks)
+        self._remove_chunks_from_removed_generations(client_name, [gen_number])
         open_client_info.client.start_changes(create_tree=False)
         open_client_info.client.remove_generation(gen_number)
 
diff --git a/obnamlib/fmt_ga/client.py b/obnamlib/fmt_ga/client.py
index ecd3b21a..65422855 100644
--- a/obnamlib/fmt_ga/client.py
+++ b/obnamlib/fmt_ga/client.py
@@ -174,7 +174,7 @@ class GAClient(object):
         else:
             return str(1)
 
-    def remove_generation(self, gen_number, ignore_missing_chunks=False):
+    def remove_generation(self, gen_number):
         self._load_data()
         remaining = []
         removed = False
diff --git a/obnamlib/plugins/forget_plugin.py b/obnamlib/plugins/forget_plugin.py
index b8606990..860cd116 100644
--- a/obnamlib/plugins/forget_plugin.py
+++ b/obnamlib/plugins/forget_plugin.py
@@ -24,8 +24,6 @@ class ForgetPlugin(obnamlib.ObnamPlugin):
     '''Forget generations.'''
 
     def enable(self):
-        forget_group = obnamlib.option_group['forget'] = 'Forgetting generations (forget)'
-
         self.app.add_subcommand(
             'forget', self.forget, arg_synopsis='[GENERATION]...')
         self.app.settings.string(
@@ -33,12 +31,6 @@ class ForgetPlugin(obnamlib.ObnamPlugin):
             'policy for what generations to keep '
             'when forgetting')
 
-        self.app.settings.boolean(
-            ['ignore-missing-chunks'],
-            'ignore missing chunks when forgetting generations',
-            default=True,
-            group=forget_group)
-
     def forget(self, args):
         '''Forget (remove) specified backup generations.'''
         self.app.settings.require('repository')
@@ -138,4 +130,4 @@ class ForgetPlugin(obnamlib.ObnamPlugin):
                 'Pretending to remove generation %s' %
                 self.repo.make_generation_spec(genid))
         else:
-            self.repo.remove_generation(genid, self.app.settings['ignore-missing-chunks'])
+            self.repo.remove_generation(genid)
diff --git a/obnamlib/repo_interface.py b/obnamlib/repo_interface.py
index 50832290..f16d6925 100644
--- a/obnamlib/repo_interface.py
+++ b/obnamlib/repo_interface.py
@@ -572,14 +572,11 @@ class RepositoryInterface(object):
         '''Set a key/value pair for a given generation.'''
         raise NotImplementedError()
 
-    def remove_generation(self, generation_id, ignore_missing_chunks=False):
+    def remove_generation(self, generation_id):
         '''Remove an existing generation.
 
         The removed generation may be the currently unfinished one.
 
-        When removing chunks, don't try to remove those that are missing
-        if ignore_missing_chunks is set to True.
-
         '''
         raise NotImplementedError()