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Diffstat (limited to 'Documentation/git-filter-branch.txt')
| -rw-r--r-- | Documentation/git-filter-branch.txt | 60 |
1 files changed, 60 insertions, 0 deletions
diff --git a/Documentation/git-filter-branch.txt b/Documentation/git-filter-branch.txt index fed6de6a7f..7ffe03f427 100644 --- a/Documentation/git-filter-branch.txt +++ b/Documentation/git-filter-branch.txt @@ -122,6 +122,10 @@ You can use the 'map' convenience function in this filter, and other convenience functions, too. For example, calling 'skip_commit "$@"' will leave out the current commit (but not its changes! If you want that, use 'git-rebase' instead). ++ +You can also use the 'git_commit_non_empty_tree "$@"' instead of +'git commit-tree "$@"' if you don't wish to keep commits with a single parent +and that makes no change to the tree. --tag-name-filter <command>:: This is the filter for rewriting tag names. When passed, @@ -151,6 +155,16 @@ to other tags will be rewritten to point to the underlying commit. The result will contain that directory (and only that) as its project root. +--prune-empty:: + Some kind of filters will generate empty commits, that left the tree + untouched. This switch allow git-filter-branch to ignore such + commits. Though, this switch only applies for commits that have one + and only one parent, it will hence keep merges points. Also, this + option is not compatible with the use of '--commit-filter'. Though you + just need to use the function 'git_commit_non_empty_tree "$@"' instead + of the 'git commit-tree "$@"' idiom in your commit filter to make that + happen. + --original <namespace>:: Use this option to set the namespace where the original commits will be stored. The default value is 'refs/original'. @@ -198,6 +212,11 @@ git filter-branch --index-filter 'git rm --cached filename' HEAD Now, you will get the rewritten history saved in HEAD. +As with using `rm filename`, `git rm --cached filename` will fail +if the file is absent from the tree of a commit. If it is not important +whether the file is already absent from the tree, you can use +`git rm --cached --ignore-unmatch filename` instead. + To rewrite the repository to look as if `foodir/` had been its project root, and discard all other history: @@ -320,6 +339,47 @@ git filter-branch --index-filter \ --------------------------------------------------------------- + +Checklist for Shrinking a Repository +------------------------------------ + +git-filter-branch is often used to get rid of a subset of files, +usually with some combination of `\--index-filter` and +`\--subdirectory-filter`. People expect the resulting repository to +be smaller than the original, but you need a few more steps to +actually make it smaller, because git tries hard not to lose your +objects until you tell it to. First make sure that: + +* You really removed all variants of a filename, if a blob was moved + over its lifetime. `git log \--name-only \--follow \--all \-- + filename` can help you find renames. + +* You really filtered all refs: use `\--tag-name-filter cat \-- + \--all` when calling git-filter-branch. + +Then there are two ways to get a smaller repository. A safer way is +to clone, that keeps your original intact. + +* Clone it with `git clone +++file:///path/to/repo+++`. The clone + will not have the removed objects. See linkgit:git-clone[1]. (Note + that cloning with a plain path just hardlinks everything!) + +If you really don't want to clone it, for whatever reasons, check the +following points instead (in this order). This is a very destructive +approach, so *make a backup* or go back to cloning it. You have been +warned. + +* Remove the original refs backed up by git-filter-branch: say `git + for-each-ref \--format="%(refname)" refs/original/ | xargs -n 1 git + update-ref -d`. + +* Expire all reflogs with `git reflog expire \--expire=now \--all`. + +* Garbage collect all unreferenced objects with `git gc \--prune=now` + (or if your git-gc is not new enough to support arguments to + `\--prune`, use `git repack -ad; git prune` instead). + + Author ------ Written by Petr "Pasky" Baudis <pasky@suse.cz>, |