# Merge & Cherrypick

Contents

- Merge & Cherrypick
  - The merge method
  - Cherrypick
  - Lower-level methods

`Repository.``merge_base`(oid, oid) → Oid

  Find as good common ancestors as possible for a merge. Returns None if there is no merge base between the commits

`Repository.``merge`(id)

  Merges the given id into HEAD.

  Merges the given commit(s) into HEAD, writing the results into the working directory. Any changes are staged for commit and any conflicts are written to the index. Callers should inspect the repository’s index after this completes, resolve any conflicts and prepare a commit.

`Repository.``merge_analysis`(id) -> (Integer, Integer)

  Analyzes the given branch and determines the opportunities for merging them into the HEAD of the repository

  The first returned value is a mixture of the GIT_MERGE_ANALYSIS_NONE, _NORMAL, _UP_TO_DATE, _FASTFORWARD and _UNBORN flags. The second value is the user’s preference from ‘merge.ff’

## The merge method

The method does a merge over the current working copy. It gets an Oid object as a parameter.

As its name says, it only does the merge, does not commit nor update the branch reference in the case of a fastforward.

For the moment, the merge does not support options, it will perform the merge with the default ones defined in GIT_MERGE_OPTS_INIT libgit2 constant.

Example:

    >>> other_branch_tip = '5ebeeebb320790caf276b9fc8b24546d63316533'
    >>> repo.merge(other_branch_tip)

You can now inspect the index file for conflicts and get back to the user to resolve if there are. Once there are no conflicts left, you can create a commit with these two parents.

    >>> user = repo.default_signature
    >>> tree = repo.index.write_tree()
    >>> message = "Merging branches"
    >>> new_commit = repo.create_commit('HEAD', user, user, message, tree,
                                        [repo.head.target, other_branch_tip])

## Cherrypick

`Repository.``cherrypick`(id)

  Cherry-pick the given oid, producing changes in the index and working directory.

  Merges the given commit into HEAD as a cherrypick, writing the results into the working directory. Any changes are staged for commit and any conflicts are written to the index. Callers should inspect the repository’s index after this completes, resolve any conflicts and prepare a commit.

Note that after a successful cherrypick you have to run `Repository.state_cleanup()` in order to get the repository out of cherrypicking mode.

## Lower-level methods

These methods allow more direct control over how to perform the merging. They do not modify the working directory and return an in-memory Index representing the result of the merge.

`Repository.``merge_commits`(ours, theirs, favor='normal')

  Merge two arbitrary commits.

  Returns: an index with the result of the merge.

  Parameters:

  ours
    The commit to take as “ours” or base.
  theirs
    The commit which will be merged into “ours”
  favor

    How to deal with file-level conflicts. Can be one of

    - normal (default). Conflicts will be preserved.
    - ours. The “ours” side of the conflict region is used.
    - theirs. The “theirs” side of the conflict region is used.
    - union. Unique lines from each side will be used.

    For all but NORMAL, the index will not record a conflict.

  Both “ours” and “theirs” can be any object which peels to a commit or the id (string or Oid) of an object which peels to a commit.

`Repository.``merge_trees`(ancestor, ours, theirs, favor='normal')

  Merge two trees.

  Returns: an Index that reflects the result of the merge.

  Parameters:

  ancestor
    The tree which is the common ancestor between ‘ours’ and ‘theirs’.
  ours
    The commit to take as “ours” or base.
  theirs
    The commit which will be merged into “ours”.
  favor

    How to deal with file-level conflicts. Can be one of:

    - normal (default). Conflicts will be preserved.
    - ours. The “ours” side of the conflict region is used.
    - theirs. The “theirs” side of the conflict region is used.
    - union. Unique lines from each side will be used.

    For all but NORMAL, the index will not record a conflict.