Conflict handling

Some operations, like merge, revert and pull, modify the contents of your working tree. These modifications are programmatically generated, and so they may conflict with the current state of your working tree. Many kinds of changes can be combined programmatically, but sometimes only a human can determine the right thing to do. When this happens Bazaar will inform you that there is a conflict and then ask you to resolve it. The command to tell Bazaar a conflict is resolved is resolve, but you must perform some action before you can do this.

Each type of conflict is explained below, and the action which must be done to resolve the conflict is outlined.

Text conflicts

Typical message:

Text conflict in FILE

These are produced when a text merge cannot completely reconcile two sets of text changes. Bazaar will emit files for each version with the extensions THIS, OTHER, and BASE. THIS is the version of the file from the target tree, i.e. the tree that you are merging changes into. OTHER is the version that you are merging into the target. BASE is an older version that is used as a basis for comparison.

In the main copy of the file, Bazaar will include all the changes that it could reconcile, and any un-reconciled conflicts are surrounded by "herringbone" markers like <<<<<<<.

Say the initial text is "The project leader released it.", and THIS modifies it to "Martin Pool released it.", while OTHER modifies it to "The project leader released Bazaar." A conflict would look like this:

<<<<<<< TREE
Martin Pool released it.
=======
The project leader released Bazaar.
>>>>>>> MERGE-SOURCE

The correct resolution would be "Martin Pool released Bazaar."

You can handle text conflicts either by editing the main copy of the file, or by invoking external tools on the THIS, OTHER and BASE versions. It's worth mentioning that resolving text conflicts rarely involves picking one set of changes over the other. More often, the two sets of changes must be intelligently combined.

If you edit the main copy, be sure to remove the herringbone markers. When you are done editing, the file should look like it never had a conflict, and be ready to commit.

When you have resolved text conflicts, just run "bzr resolve", and Bazaar will auto-detect which conflicts you have resolved.

Content conflicts

Typical message:

Contents conflict in FILE

This conflict happens when there are conflicting changes in the target tree and the merge source, but the conflicted items are not text files. They may be binary files, or symlinks, or directories. It can even happen with files that are deleted on one side, and modified on the other.

Like text conflicts, Bazaar will emit THIS, OTHER and BASE files. (They may be regular files, symlinks or directories). But it will not include a "main copy" of the file with herringbone conflict markers. It will appear that the "main copy" has been renamed to THIS or OTHER.

To resolve this, use "bzr mv" to rename the file back to its normal name, and combine the changes manually. When you are satisfied, run "bzr resolve FILE". Bazaar cannot auto-detect when conflicts of this kind have been resolved.

Duplicate Paths

Typical message:

Conflict adding file FILE.  Moved existing file to FILE.moved.

Sometimes Bazaar will attempt to create a file using a pathname that has already been used. The existing file will be renamed to "FILE.moved". If you wish, you can rename either one of these files, or combine their contents. When you are satisfied, you can run "bzr resolve FILE" to mark the conflict as resolved.

Unversioned Parent

Typical message:

Conflict because FILE is not versioned, but has versioned children.

Sometimes Bazaar will attempt to create a file whose parent directory is not versioned. This happens when the directory has been deleted in the target, but has a new child in the source, or vice versa. In this situation, Bazaar will version the parent directory as well. Resolving this issue depends very much on the particular scenario. You may wish to rename or delete either the file or the directory. When you are satisfied, you can run "bzr resolve FILE" to mark the conflict as resolved.

Missing Parent

Typical message:

Conflict adding files to FILE.  Created directory.

This happens when a file has been deleted in the target, but has new children in the source. This is similar to the "unversioned parent" conflict, except that the parent directory does not exist, instead of just being unversioned. In this situation, Bazaar will create the missing parent. Resolving this issue depends very much on the particular scenario. You may wish to rename or delete either the file or the directory. When you are satisfied, you can run "bzr resolve FILE" to mark the conflict as resolved.

Deleting Parent

Typical message:

Conflict: can't delete FILE because it is not empty.  Not deleting.

This is the opposite of "missing parent". A directory is deleted in the source, but has new children in the target. Bazaar will retain the directory. Resolving this issue depends very much on the particular scenario. You may wish to rename or delete either the file or the directory. When you are satisfied, you can run "bzr resolve FILE" to mark the conflict as resolved.

Path Conflict

Typical message:

Path conflict: PATH1 / PATH2

This happens when the source and target have each modified the name or parent directory of a file. Bazaar will use the path elements from the source. You can rename the file, and once you have, run "bzr resolve FILE" to mark the conflict as resolved.

Parent Loop

Typical message:

Conflict moving FILE into DIRECTORY.  Cancelled move.

This happens when the source and the target have each moved directories, so that, if the change could be applied, a directory would be contained by itself. For example:

$ bzr init
$ bzr mkdir a
$ bzr mkdir b
$ bzr commit -m "BASE"
$ bzr branch . ../other
$ bzr mv a b
$ bzr commit -m "THIS"
$ bzr mv ../other/b ../other/a
$ bzr commit ../other -m "OTHER"
$ bzr merge ../other

In this situation, Bazaar will cancel the move, and leave "a" in "b". You can rename the directories if you like, and once you have, run "bzr resolve FILE" to mark the conflict as resolved.

MalformedTransform

It is possible (though very rare) for Bazaar to raise a MalformedTransform exception. This means that Bazaar encountered a filesystem conflict that it was unable to resolve. This usually indicates a bug. Please let us know if you encounter this. Our bug tracker is at https://launchpad.net/bzr/+bugs