这将合并现有的baseBranch中的newBranch

git checkout <baseBranch> // this will checkout baseBranch
git merge -s ours <newBranch> // this will simple merge newBranch in baseBranch
git rm -rf . // this will remove all non references files from baseBranch (deleted in newBranch)
git checkout newBranch -- . //this will replace all conflicted files in baseBranch

如果你在分支A上，请:

git merge -s recursive -X theirs B

在git版本1.7.8上测试

这一个使用了git管道命令读树，但是使得整个工作流程更短。

git checkout <base-branch>

git merge --no-commit -s ours <their-branch>
git read-tree -u --reset <their-branch>
git commit

# Check your work!
git diff <their-branch>

从现在起，我一直使用Paul Pladijs的答案。我发现，你可以做一个“正常的”合并，发生冲突，所以你这样做

git checkout --theirs <file>

通过使用来自其他分支的修订来解决冲突。如果对每个文件执行此操作，则会得到与预期相同的行为

git merge <branch> -s theirs

无论如何，这种努力比合并策略要多!(这是用git 1.8.0版本测试的)

这将合并现有的baseBranch中的newBranch

git checkout <baseBranch> // this will checkout baseBranch
git merge -s ours <newBranch> // this will simple merge newBranch in baseBranch
git rm -rf . // this will remove all non references files from baseBranch (deleted in newBranch)
git checkout newBranch -- . //this will replace all conflicted files in baseBranch

将分支b合并到签出的分支cha的一个可能的和经过测试的解决方案:

# in case branchA is not our current branch
git checkout branchA

# make merge commit but without conflicts!!
# the contents of 'ours' will be discarded later
git merge -s ours branchB    

# make temporary branch to merged commit
git branch branchTEMP         

# get contents of working tree and index to the one of branchB
git reset --hard branchB

# reset to our merged commit but 
# keep contents of working tree and index
git reset --soft branchTEMP

# change the contents of the merged commit
# with the contents of branchB
git commit --amend

# get rid off our temporary branch
git branch -D branchTEMP

# verify that the merge commit contains only contents of branchB
git diff HEAD branchB

为了实现自动化，您可以使用branchA和branchB作为参数将其包装到脚本中。

这个解决方案保留了合并提交的第一个和第二个父节点，就像你期望git merge -s their branchB一样。