Rev 97: Merge James Westby's patch for bug 195133. in http://bazaar.launchpad.net/~bzr-loom-devs/bzr-loom/trunk/

[Robert Collins]

At http://bazaar.launchpad.net/~bzr-loom-devs/bzr-loom/trunk/

------------------------------------------------------------
revno: 97 [merge]
revision-id: robertc at robertcollins.net-20090618062818-l5bsw9tz497brtnl
parent: robertc at robertcollins.net-20090618031414-ide5ozp7c1pkza51
parent: jw+debian at jameswestby.net-20080224230029-zisv2nyallbtafu6
committer: Robert Collins <robertc at robertcollins.net>
branch nick: trunk
timestamp: Thu 2009-06-18 16:28:18 +1000
message:
  Merge James Westby's patch for bug 195133.
modified:
  NEWS                           news-20080228111444-miryhm4hma987q57-1
  TODO                           TODO-20060619140504-t23oktsxx8wv9lk7-1
  tests/blackbox.py              blackbox.py-20060620084702-jnrwijq76kg45klj-7
  tree.py                        tree.py-20060701085538-3ajq87mglfa5ryqa-1
=== modified file 'NEWS'
--- a/NEWS	2009-06-18 03:14:14 +0000
+++ b/NEWS	2009-06-18 06:28:18 +0000
@@ -27,6 +27,10 @@
     * ``up`` and ``down`` are now aliases for ``up-thread`` and
       ``down-thread`` respectively.
 
+    * ``up-thread`` now notifies when a thread becomes empty. This is a step
+      towards removing it automatically/prompting to do so.
+      (James Westby, #195133)
+
   BUGFIXES:
 
     * ``pull`` expects the keywork local. (Mark Lee, #379347)

=== modified file 'TODO'
--- a/TODO	2008-01-20 07:34:29 +0000
+++ b/TODO	2009-06-18 06:28:18 +0000
@@ -95,7 +95,7 @@
   TODO either means changing 'diff's defaults, adding a flag to diff, or using
   a different revspec prefix; or something like that.)
 - export-patch to export the diff from this thread to the lower thread (using -ancestry logic) to a file named as the warp is named. (what about / ?)
-- during up-thread, if we could pull or if there is no diff, then the thread has been merged, offer to remove it.
+- during up-thread, if we could pull or if there is no diff, then the thread has been merged, offer to remove it. (Currently suggests to remove it).
 - loom to have the same 'tree root id' as its branches, to allow nested looms by reference. EEK!.
 - show-loom to allow -r -1.
 - combine-thread to warn if the thread being combined has changes not present in the one below it. I.e. by ancestry, or by doing a merge and recording differences. For bonus points, do the merge, but record the lower thread as the last-revision in the tree still, and set no pending-merges. This preserves the difference whilst still combining the threads.

=== modified file 'tests/blackbox.py'
--- a/tests/blackbox.py	2008-10-02 01:24:28 +0000
+++ b/tests/blackbox.py	2009-06-18 06:28:18 +0000
@@ -431,7 +431,9 @@
         self.assertEqual('', out)
         self.assertEqual(
             "All changes applied successfully.\n"
-            "Moved to thread 'patch'.\n", err)
+            "Moved to thread 'patch'.\n"
+            'This thread is now empty, you may wish to run "bzr '
+            'combine-thread" to remove it.\n', err)
         self.assertEqual('patch', tree.branch.nick)
         # the tree needs to be updated.
         self.assertEqual(patch_rev, tree.last_revision())
@@ -491,6 +493,55 @@
         branch = _mod_branch.Branch.open('.')
         self.assertEqual('top', branch.nick)
 
+    def test_up_with_clean_merge_leaving_thread_empty(self):
+        """This tests what happens when a thread becomes empty.
+        
+        A thread becomes empty when all its changes are included in
+        a lower thread, and so its diff to the thread below contains
+        nothing.
+        
+        The user should be warned when this happens.
+        """
+        tree = self.get_vendor_loom()
+        self.build_tree(['afile'])
+        tree.add('afile')
+        patch_rev = tree.commit('add afile in base')
+        tree.branch.new_thread('patch')
+        tree.branch.nick = 'patch'
+        # make a change to afile in patch.
+        f = open('afile', 'wb')
+        try:
+            f.write('new contents of afile\n')
+        finally:
+            f.close()
+        patch_rev = tree.commit('make a change to afile')
+        # make the same change in vendor.
+        self.run_bzr(['down-thread'])
+        f = open('afile', 'wb')
+        try:
+            f.write('new contents of afile\n')
+        finally:
+            f.close()
+        vendor_release = tree.commit('make the same change to afile')
+        # check that the trees no longer differ after the up merge,
+        # and that we are 
+        out, err = self.run_bzr(['up-thread'])
+        self.assertEqual('', out)
+        self.assertEqual("All changes applied successfully.\n"
+            "Moved to thread 'patch'.\n"
+            'This thread is now empty, you may wish to run "bzr '
+            'combine-thread" to remove it.\n', err)
+        self.assertEqual('patch', tree.branch.nick)
+        # the tree needs to be updated.
+        self.assertEqual(patch_rev, tree.last_revision())
+        # the branch needs to be updated.
+        self.assertEqual(patch_rev, tree.branch.last_revision())
+        self.assertTrue(tree.has_filename('afile'))
+        # diff should return 0 now as we have no uncommitted changes.
+        self.run_bzr(['diff'])
+        self.assertEqual([patch_rev, vendor_release], tree.get_parent_ids())
+
+
 
 class TestPush(TestsWithLooms):
 

=== modified file 'tree.py'
--- a/tree.py	2008-10-02 01:24:28 +0000
+++ b/tree.py	2009-06-18 06:28:18 +0000
@@ -128,6 +128,11 @@
         # update the branch nick.
         self.tree.branch.nick = new_thread_name
         bzrlib.trace.note("Moved to thread '%s'." % new_thread_name)
+        if (basis_tree is not None and 
+            not result and not
+            self.tree.changes_from(basis_tree).has_changed()):
+            bzrlib.trace.info("This thread is now empty, you may wish to "
+                'run "bzr combine-thread" to remove it.')
         if result != 0:
             return 1
         else: