Merge lp:~jelmer/brz/switch-self into lp:brz

[Jelmer Vernooij]

Two switch fixes (relative paths in lightweight checkout URLs of colocated branches (#919169), print error when attempting to create a branch reference loop (#1018628))

Two colocated branch fixes:

* Use relative paths in lightweight checkout URLs of colocated branches (#919169)
* Print an error when attempting to create a branch reference loop (#1018628)

[Martin Packman (gz)]

Thank you! Great to fix some of these gotchas with colo branches and switch.

review: Approve

[The Breezy Bot (the-breezy-bot)]

Running landing tests failed
https://ci.breezy-vcs.org/job/brz-dev/97/

[The Breezy Bot (the-breezy-bot)]

Running landing tests failed
https://ci.breezy-vcs.org/job/brz-dev/110/

=== modified file 'breezy/builtins.py'
--- breezy/builtins.py	2018-04-01 18:09:31 +0000
+++ breezy/builtins.py	2018-04-03 02:46:28 +0000
@@ -6352,8 +6352,14 @@
                     possible_transports=possible_transports)
         if revision is not None:
             revision = revision.as_revision_id(to_branch)
-        switch.switch(control_dir, to_branch, force, revision_id=revision,
-                      store_uncommitted=store)
+        try:
+            switch.switch(control_dir, to_branch, force, revision_id=revision,
+                          store_uncommitted=store)
+        except controldir.BranchReferenceLoop:
+            raise errors.BzrCommandError(
+                    gettext('switching would create a branch reference loop. '
+                            'Use the "bzr up" command to switch to a '
+                            'different revision.'))
         if had_explicit_nick:
             branch = control_dir.open_branch() #get the new branch!
             branch.nick = to_branch.nick

=== modified file 'breezy/bzr/branch.py'
--- breezy/bzr/branch.py	2018-03-25 00:39:16 +0000
+++ breezy/bzr/branch.py	2018-04-03 02:46:28 +0000
@@ -946,12 +946,22 @@
     def get_reference(self, a_controldir, name=None):
         """See BranchFormat.get_reference()."""
         transport = a_controldir.get_branch_transport(None, name=name)
-        return transport.get_bytes('location')
+        url = urlutils.split_segment_parameters(a_controldir.user_url)[0]
+        return urlutils.join(url, transport.get_bytes('location'))
+
+    def _write_reference(self, a_controldir, transport, to_branch):
+        to_url = to_branch.user_url
+        if a_controldir.control_url == to_branch.controldir.control_url:
+            # Write relative paths for colocated branches, but absolute
+            # paths for everything else. This is for the benefit
+            # of older bzr versions that don't support relative paths.
+            to_url = urlutils.relative_url(a_controldir.user_url, to_branch.user_url)
+        transport.put_bytes('location', to_url)
 
     def set_reference(self, a_controldir, name, to_branch):
         """See BranchFormat.set_reference()."""
         transport = a_controldir.get_branch_transport(None, name=name)
-        location = transport.put_bytes('location', to_branch.base)
+        self._write_reference(a_controldir, transport, to_branch)
 
     def initialize(self, a_controldir, name=None, target_branch=None,
             repository=None, append_revisions_only=None):
@@ -966,7 +976,7 @@
         if name is None:
             name = a_controldir._get_selected_branch()
         branch_transport = a_controldir.get_branch_transport(self, name=name)
-        branch_transport.put_bytes('location', target_branch.user_url)
+        self._write_reference(a_controldir, branch_transport, target_branch)
         branch_transport.put_bytes('format', self.as_string())
         branch = self.open(a_controldir, name, _found=True,
             possible_transports=[target_branch.controldir.root_transport])

=== modified file 'breezy/bzr/bzrdir.py'
--- breezy/bzr/bzrdir.py	2018-03-25 00:39:16 +0000
+++ breezy/bzr/bzrdir.py	2018-04-03 02:46:28 +0000
@@ -955,6 +955,9 @@
 
     def set_branch_reference(self, target_branch, name=None):
         format = _mod_bzrbranch.BranchReferenceFormat()
+        if (self.control_url == target_branch.controldir.control_url and
+            name == target_branch.name):
+            raise controldir.BranchReferenceLoop(target_branch)
         return format.initialize(self, target_branch=target_branch, name=name)
 
     def get_branch_transport(self, branch_format, name=None):

=== modified file 'breezy/controldir.py'
--- breezy/controldir.py	2018-03-04 19:06:44 +0000
+++ breezy/controldir.py	2018-04-03 02:46:28 +0000
@@ -59,6 +59,14 @@
         errors.BzrError.__init__(self, format=format, url=url)
 
 
+class BranchReferenceLoop(errors.BzrError):
+
+    _fmt = "Can not create branch reference that points at branch itself."
+
+    def __init__(self, branch):
+        errors.BzrError.__init__(self, branch=branch)
+
+
 class ControlComponent(object):
     """Abstract base class for control directory components.
 

=== modified file 'breezy/tests/blackbox/test_checkout.py'
--- breezy/tests/blackbox/test_checkout.py	2018-02-18 15:21:06 +0000
+++ breezy/tests/blackbox/test_checkout.py	2018-04-03 02:46:28 +0000
@@ -191,7 +191,7 @@
         # We should always be creating a lighweight checkout for colocated
         # branches.
         self.assertEqual(
-            target.open_branch(name='somebranch').base,
+            target.open_branch(name='somebranch').user_url,
             target.get_branch_reference(name=""))
 
 

=== modified file 'breezy/tests/blackbox/test_switch.py'
--- breezy/tests/blackbox/test_switch.py	2018-02-18 15:21:06 +0000
+++ breezy/tests/blackbox/test_switch.py	2018-04-03 02:46:28 +0000
@@ -529,3 +529,50 @@
         self.assertPathDoesNotExist('checkout/a')
         self.run_bzr(['switch', '-d', 'checkout', 'orig'])
         self.assertPathDoesNotExist('checkout/a')
+
+
+class TestSwitchStandAloneCorruption(TestCaseWithTransport):
+
+    def test_empty_tree_switch(self):
+        """switch . on an empty tree gets infinite recursion
+
+        Inspired by: https://bugs.launchpad.net/bzr/+bug/1018628
+        """
+        self.script_runner = script.ScriptRunner()
+        self.script_runner.run_script(self, '''
+            $ brz init
+            Created a standalone tree (format: 2a)
+            $ brz switch .
+            2>brz: ERROR: switching would create a branch reference loop. Use the "bzr up" command to switch to a different revision.
+            ''')
+
+    def test_switch_on_previous_rev(self):
+        """switch to previous rev in a standalone directory
+
+        Inspired by: https://bugs.launchpad.net/brz/+bug/1018628
+        """
+        self.script_runner = script.ScriptRunner()
+        self.script_runner.run_script(self, '''
+           $ brz init
+           Created a standalone tree (format: 2a)
+           $ brz commit -m 1 --unchanged
+           $ brz commit -m 2 --unchanged
+           $ brz switch -r 1
+           2>brz: ERROR: switching would create a branch reference loop. Use the "bzr up" command to switch to a different revision.''',
+           null_output_matches_anything=True)
+
+    def test_switch_create_colo_locks_repo_path(self):
+        self.script_runner = script.ScriptRunner()
+        self.script_runner.run_script(self, '''
+            $ mkdir mywork
+            $ cd mywork
+            $ brz init
+            Created a standalone tree (format: 2a)
+            $ echo A > a && brz add a && brz commit -m A
+            $ brz switch -b br1
+            $ cd ..
+            $ mv mywork mywork1
+            $ cd mywork1
+            $ brz branches
+            * br1
+            ''', null_output_matches_anything=True)

=== modified file 'breezy/tests/per_controldir_colo/test_supported.py'
--- breezy/tests/per_controldir_colo/test_supported.py	2018-03-04 03:27:09 +0000
+++ breezy/tests/per_controldir_colo/test_supported.py	2018-04-03 02:46:28 +0000
@@ -17,6 +17,7 @@
 """Tests for bzr directories that support colocated branches."""
 
 from breezy.branch import Branch
+from breezy.controldir import BranchReferenceLoop
 from breezy import (
     branchbuilder,
     errors,
@@ -166,3 +167,15 @@
                 'Control dir does not support creating branch references.')
         self.assertEqual(referenced.user_url,
                          repo.controldir.get_branch_reference('foo'))
+
+    def test_branch_reference_loop(self):
+        repo = self.make_repository('repo')
+        to_branch = self.create_branch(repo.controldir, name='somebranch')
+        try:
+            self.assertRaises(
+                BranchReferenceLoop,
+                repo.controldir.set_branch_reference,
+                to_branch, name='somebranch')
+        except errors.IncompatibleFormat:
+            raise tests.TestNotApplicable(
+                'Control dir does not support creating branch references.')