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diff --git a/third_party/git/Documentation/git-filter-branch.txt b/third_party/git/Documentation/git-filter-branch.txt deleted file mode 100644 index 62e482a95e..0000000000 --- a/third_party/git/Documentation/git-filter-branch.txt +++ /dev/null @@ -1,703 +0,0 @@ -git-filter-branch(1) -==================== - -NAME ----- -git-filter-branch - Rewrite branches - -SYNOPSIS --------- -[verse] -'git filter-branch' [--setup <command>] [--subdirectory-filter <directory>] - [--env-filter <command>] [--tree-filter <command>] - [--index-filter <command>] [--parent-filter <command>] - [--msg-filter <command>] [--commit-filter <command>] - [--tag-name-filter <command>] [--prune-empty] - [--original <namespace>] [-d <directory>] [-f | --force] - [--state-branch <branch>] [--] [<rev-list options>...] - -WARNING -------- -'git filter-branch' has a plethora of pitfalls that can produce non-obvious -manglings of the intended history rewrite (and can leave you with little -time to investigate such problems since it has such abysmal performance). -These safety and performance issues cannot be backward compatibly fixed and -as such, its use is not recommended. Please use an alternative history -filtering tool such as https://github.com/newren/git-filter-repo/[git -filter-repo]. If you still need to use 'git filter-branch', please -carefully read <<SAFETY>> (and <<PERFORMANCE>>) to learn about the land -mines of filter-branch, and then vigilantly avoid as many of the hazards -listed there as reasonably possible. - -DESCRIPTION ------------ -Lets you rewrite Git revision history by rewriting the branches mentioned -in the <rev-list options>, applying custom filters on each revision. -Those filters can modify each tree (e.g. removing a file or running -a perl rewrite on all files) or information about each commit. -Otherwise, all information (including original commit times or merge -information) will be preserved. - -The command will only rewrite the _positive_ refs mentioned in the -command line (e.g. if you pass 'a..b', only 'b' will be rewritten). -If you specify no filters, the commits will be recommitted without any -changes, which would normally have no effect. Nevertheless, this may be -useful in the future for compensating for some Git bugs or such, -therefore such a usage is permitted. - -*NOTE*: This command honors `.git/info/grafts` file and refs in -the `refs/replace/` namespace. -If you have any grafts or replacement refs defined, running this command -will make them permanent. - -*WARNING*! The rewritten history will have different object names for all -the objects and will not converge with the original branch. You will not -be able to easily push and distribute the rewritten branch on top of the -original branch. Please do not use this command if you do not know the -full implications, and avoid using it anyway, if a simple single commit -would suffice to fix your problem. (See the "RECOVERING FROM UPSTREAM -REBASE" section in linkgit:git-rebase[1] for further information about -rewriting published history.) - -Always verify that the rewritten version is correct: The original refs, -if different from the rewritten ones, will be stored in the namespace -'refs/original/'. - -Note that since this operation is very I/O expensive, it might -be a good idea to redirect the temporary directory off-disk with the -`-d` option, e.g. on tmpfs. Reportedly the speedup is very noticeable. - - -Filters -~~~~~~~ - -The filters are applied in the order as listed below. The <command> -argument is always evaluated in the shell context using the 'eval' command -(with the notable exception of the commit filter, for technical reasons). -Prior to that, the `$GIT_COMMIT` environment variable will be set to contain -the id of the commit being rewritten. Also, GIT_AUTHOR_NAME, -GIT_AUTHOR_EMAIL, GIT_AUTHOR_DATE, GIT_COMMITTER_NAME, GIT_COMMITTER_EMAIL, -and GIT_COMMITTER_DATE are taken from the current commit and exported to -the environment, in order to affect the author and committer identities of -the replacement commit created by linkgit:git-commit-tree[1] after the -filters have run. - -If any evaluation of <command> returns a non-zero exit status, the whole -operation will be aborted. - -A 'map' function is available that takes an "original sha1 id" argument -and outputs a "rewritten sha1 id" if the commit has been already -rewritten, and "original sha1 id" otherwise; the 'map' function can -return several ids on separate lines if your commit filter emitted -multiple commits. - - -OPTIONS -------- - ---setup <command>:: - This is not a real filter executed for each commit but a one - time setup just before the loop. Therefore no commit-specific - variables are defined yet. Functions or variables defined here - can be used or modified in the following filter steps except - the commit filter, for technical reasons. - ---subdirectory-filter <directory>:: - Only look at the history which touches the given subdirectory. - The result will contain that directory (and only that) as its - project root. Implies <<Remap_to_ancestor>>. - ---env-filter <command>:: - This filter may be used if you only need to modify the environment - in which the commit will be performed. Specifically, you might - want to rewrite the author/committer name/email/time environment - variables (see linkgit:git-commit-tree[1] for details). - ---tree-filter <command>:: - This is the filter for rewriting the tree and its contents. - The argument is evaluated in shell with the working - directory set to the root of the checked out tree. The new tree - is then used as-is (new files are auto-added, disappeared files - are auto-removed - neither .gitignore files nor any other ignore - rules *HAVE ANY EFFECT*!). - ---index-filter <command>:: - This is the filter for rewriting the index. It is similar to the - tree filter but does not check out the tree, which makes it much - faster. Frequently used with `git rm --cached - --ignore-unmatch ...`, see EXAMPLES below. For hairy - cases, see linkgit:git-update-index[1]. - ---parent-filter <command>:: - This is the filter for rewriting the commit's parent list. - It will receive the parent string on stdin and shall output - the new parent string on stdout. The parent string is in - the format described in linkgit:git-commit-tree[1]: empty for - the initial commit, "-p parent" for a normal commit and - "-p parent1 -p parent2 -p parent3 ..." for a merge commit. - ---msg-filter <command>:: - This is the filter for rewriting the commit messages. - The argument is evaluated in the shell with the original - commit message on standard input; its standard output is - used as the new commit message. - ---commit-filter <command>:: - This is the filter for performing the commit. - If this filter is specified, it will be called instead of the - 'git commit-tree' command, with arguments of the form - "<TREE_ID> [(-p <PARENT_COMMIT_ID>)...]" and the log message on - stdin. The commit id is expected on stdout. -+ -As a special extension, the commit filter may emit multiple -commit ids; in that case, the rewritten children of the original commit will -have all of them as parents. -+ -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, - it will be called for every tag ref that points to a rewritten - object (or to a tag object which points to a rewritten object). - The original tag name is passed via standard input, and the new - tag name is expected on standard output. -+ -The original tags are not deleted, but can be overwritten; -use "--tag-name-filter cat" to simply update the tags. In this -case, be very careful and make sure you have the old tags -backed up in case the conversion has run afoul. -+ -Nearly proper rewriting of tag objects is supported. If the tag has -a message attached, a new tag object will be created with the same message, -author, and timestamp. If the tag has a signature attached, the -signature will be stripped. It is by definition impossible to preserve -signatures. The reason this is "nearly" proper, is because ideally if -the tag did not change (points to the same object, has the same name, etc.) -it should retain any signature. That is not the case, signatures will always -be removed, buyer beware. There is also no support for changing the -author or timestamp (or the tag message for that matter). Tags which point -to other tags will be rewritten to point to the underlying commit. - ---prune-empty:: - Some filters will generate empty commits that leave the tree untouched. - This option instructs git-filter-branch to remove such commits if they - have exactly one or zero non-pruned parents; merge commits will - therefore remain intact. This option cannot be used together with - `--commit-filter`, though the same effect can be achieved by using the - provided `git_commit_non_empty_tree` function in a commit filter. - ---original <namespace>:: - Use this option to set the namespace where the original commits - will be stored. The default value is 'refs/original'. - --d <directory>:: - Use this option to set the path to the temporary directory used for - rewriting. When applying a tree filter, the command needs to - temporarily check out the tree to some directory, which may consume - considerable space in case of large projects. By default it - does this in the `.git-rewrite/` directory but you can override - that choice by this parameter. - --f:: ---force:: - 'git filter-branch' refuses to start with an existing temporary - directory or when there are already refs starting with - 'refs/original/', unless forced. - ---state-branch <branch>:: - This option will cause the mapping from old to new objects to - be loaded from named branch upon startup and saved as a new - commit to that branch upon exit, enabling incremental of large - trees. If '<branch>' does not exist it will be created. - -<rev-list options>...:: - Arguments for 'git rev-list'. All positive refs included by - these options are rewritten. You may also specify options - such as `--all`, but you must use `--` to separate them from - the 'git filter-branch' options. Implies <<Remap_to_ancestor>>. - - -[[Remap_to_ancestor]] -Remap to ancestor -~~~~~~~~~~~~~~~~~ - -By using linkgit:git-rev-list[1] arguments, e.g., path limiters, you can limit the -set of revisions which get rewritten. However, positive refs on the command -line are distinguished: we don't let them be excluded by such limiters. For -this purpose, they are instead rewritten to point at the nearest ancestor that -was not excluded. - - -EXIT STATUS ------------ - -On success, the exit status is `0`. If the filter can't find any commits to -rewrite, the exit status is `2`. On any other error, the exit status may be -any other non-zero value. - - -EXAMPLES --------- - -Suppose you want to remove a file (containing confidential information -or copyright violation) from all commits: - -------------------------------------------------------- -git filter-branch --tree-filter 'rm filename' HEAD -------------------------------------------------------- - -However, if the file is absent from the tree of some commit, -a simple `rm filename` will fail for that tree and commit. -Thus you may instead want to use `rm -f filename` as the script. - -Using `--index-filter` with 'git rm' yields a significantly faster -version. Like with using `rm filename`, `git rm --cached filename` -will fail if the file is absent from the tree of a commit. If you -want to "completely forget" a file, it does not matter when it entered -history, so we also add `--ignore-unmatch`: - --------------------------------------------------------------------------- -git filter-branch --index-filter 'git rm --cached --ignore-unmatch filename' HEAD --------------------------------------------------------------------------- - -Now, you will get the rewritten history saved in HEAD. - -To rewrite the repository to look as if `foodir/` had been its project -root, and discard all other history: - -------------------------------------------------------- -git filter-branch --subdirectory-filter foodir -- --all -------------------------------------------------------- - -Thus you can, e.g., turn a library subdirectory into a repository of -its own. Note the `--` that separates 'filter-branch' options from -revision options, and the `--all` to rewrite all branches and tags. - -To set a commit (which typically is at the tip of another -history) to be the parent of the current initial commit, in -order to paste the other history behind the current history: - -------------------------------------------------------------------- -git filter-branch --parent-filter 'sed "s/^\$/-p <graft-id>/"' HEAD -------------------------------------------------------------------- - -(if the parent string is empty - which happens when we are dealing with -the initial commit - add graftcommit as a parent). Note that this assumes -history with a single root (that is, no merge without common ancestors -happened). If this is not the case, use: - --------------------------------------------------------------------------- -git filter-branch --parent-filter \ - 'test $GIT_COMMIT = <commit-id> && echo "-p <graft-id>" || cat' HEAD --------------------------------------------------------------------------- - -or even simpler: - ------------------------------------------------ -git replace --graft $commit-id $graft-id -git filter-branch $graft-id..HEAD ------------------------------------------------ - -To remove commits authored by "Darl McBribe" from the history: - ------------------------------------------------------------------------------- -git filter-branch --commit-filter ' - if [ "$GIT_AUTHOR_NAME" = "Darl McBribe" ]; - then - skip_commit "$@"; - else - git commit-tree "$@"; - fi' HEAD ------------------------------------------------------------------------------- - -The function 'skip_commit' is defined as follows: - --------------------------- -skip_commit() -{ - shift; - while [ -n "$1" ]; - do - shift; - map "$1"; - shift; - done; -} --------------------------- - -The shift magic first throws away the tree id and then the -p -parameters. Note that this handles merges properly! In case Darl -committed a merge between P1 and P2, it will be propagated properly -and all children of the merge will become merge commits with P1,P2 -as their parents instead of the merge commit. - -*NOTE* the changes introduced by the commits, and which are not reverted -by subsequent commits, will still be in the rewritten branch. If you want -to throw out _changes_ together with the commits, you should use the -interactive mode of 'git rebase'. - -You can rewrite the commit log messages using `--msg-filter`. For -example, 'git svn-id' strings in a repository created by 'git svn' can -be removed this way: - -------------------------------------------------------- -git filter-branch --msg-filter ' - sed -e "/^git-svn-id:/d" -' -------------------------------------------------------- - -If you need to add 'Acked-by' lines to, say, the last 10 commits (none -of which is a merge), use this command: - --------------------------------------------------------- -git filter-branch --msg-filter ' - cat && - echo "Acked-by: Bugs Bunny <bunny@bugzilla.org>" -' HEAD~10..HEAD --------------------------------------------------------- - -The `--env-filter` option can be used to modify committer and/or author -identity. For example, if you found out that your commits have the wrong -identity due to a misconfigured user.email, you can make a correction, -before publishing the project, like this: - --------------------------------------------------------- -git filter-branch --env-filter ' - if test "$GIT_AUTHOR_EMAIL" = "root@localhost" - then - GIT_AUTHOR_EMAIL=john@example.com - fi - if test "$GIT_COMMITTER_EMAIL" = "root@localhost" - then - GIT_COMMITTER_EMAIL=john@example.com - fi -' -- --all --------------------------------------------------------- - -To restrict rewriting to only part of the history, specify a revision -range in addition to the new branch name. The new branch name will -point to the top-most revision that a 'git rev-list' of this range -will print. - -Consider this history: - ------------------- - D--E--F--G--H - / / -A--B-----C ------------------- - -To rewrite only commits D,E,F,G,H, but leave A, B and C alone, use: - --------------------------------- -git filter-branch ... C..H --------------------------------- - -To rewrite commits E,F,G,H, use one of these: - ----------------------------------------- -git filter-branch ... C..H --not D -git filter-branch ... D..H --not C ----------------------------------------- - -To move the whole tree into a subdirectory, or remove it from there: - ---------------------------------------------------------------- -git filter-branch --index-filter \ - 'git ls-files -s | sed "s-\t\"*-&newsubdir/-" | - GIT_INDEX_FILE=$GIT_INDEX_FILE.new \ - git update-index --index-info && - mv "$GIT_INDEX_FILE.new" "$GIT_INDEX_FILE"' HEAD ---------------------------------------------------------------- - - - -CHECKLIST FOR SHRINKING A REPOSITORY ------------------------------------- - -git-filter-branch can be 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). - -[[PERFORMANCE]] -PERFORMANCE ------------ - -The performance of git-filter-branch is glacially slow; its design makes it -impossible for a backward-compatible implementation to ever be fast: - -* In editing files, git-filter-branch by design checks out each and - every commit as it existed in the original repo. If your repo has - `10^5` files and `10^5` commits, but each commit only modifies five - files, then git-filter-branch will make you do `10^10` modifications, - despite only having (at most) `5*10^5` unique blobs. - -* If you try and cheat and try to make git-filter-branch only work on - files modified in a commit, then two things happen - - ** you run into problems with deletions whenever the user is simply - trying to rename files (because attempting to delete files that - don't exist looks like a no-op; it takes some chicanery to remap - deletes across file renames when the renames happen via arbitrary - user-provided shell) - - ** even if you succeed at the map-deletes-for-renames chicanery, you - still technically violate backward compatibility because users - are allowed to filter files in ways that depend upon topology of - commits instead of filtering solely based on file contents or - names (though this has not been observed in the wild). - -* Even if you don't need to edit files but only want to e.g. rename or - remove some and thus can avoid checking out each file (i.e. you can - use --index-filter), you still are passing shell snippets for your - filters. This means that for every commit, you have to have a - prepared git repo where those filters can be run. That's a - significant setup. - -* Further, several additional files are created or updated per commit - by git-filter-branch. Some of these are for supporting the - convenience functions provided by git-filter-branch (such as map()), - while others are for keeping track of internal state (but could have - also been accessed by user filters; one of git-filter-branch's - regression tests does so). This essentially amounts to using the - filesystem as an IPC mechanism between git-filter-branch and the - user-provided filters. Disks tend to be a slow IPC mechanism, and - writing these files also effectively represents a forced - synchronization point between separate processes that we hit with - every commit. - -* The user-provided shell commands will likely involve a pipeline of - commands, resulting in the creation of many processes per commit. - Creating and running another process takes a widely varying amount - of time between operating systems, but on any platform it is very - slow relative to invoking a function. - -* git-filter-branch itself is written in shell, which is kind of slow. - This is the one performance issue that could be backward-compatibly - fixed, but compared to the above problems that are intrinsic to the - design of git-filter-branch, the language of the tool itself is a - relatively minor issue. - - ** Side note: Unfortunately, people tend to fixate on the - written-in-shell aspect and periodically ask if git-filter-branch - could be rewritten in another language to fix the performance - issues. Not only does that ignore the bigger intrinsic problems - with the design, it'd help less than you'd expect: if - git-filter-branch itself were not shell, then the convenience - functions (map(), skip_commit(), etc) and the `--setup` argument - could no longer be executed once at the beginning of the program - but would instead need to be prepended to every user filter (and - thus re-executed with every commit). - -The https://github.com/newren/git-filter-repo/[git filter-repo] tool is -an alternative to git-filter-branch which does not suffer from these -performance problems or the safety problems (mentioned below). For those -with existing tooling which relies upon git-filter-branch, 'git -filter-repo' also provides -https://github.com/newren/git-filter-repo/blob/master/contrib/filter-repo-demos/filter-lamely[filter-lamely], -a drop-in git-filter-branch replacement (with a few caveats). While -filter-lamely suffers from all the same safety issues as -git-filter-branch, it at least ameliorates the performance issues a -little. - -[[SAFETY]] -SAFETY ------- - -git-filter-branch is riddled with gotchas resulting in various ways to -easily corrupt repos or end up with a mess worse than what you started -with: - -* Someone can have a set of "working and tested filters" which they - document or provide to a coworker, who then runs them on a different - OS where the same commands are not working/tested (some examples in - the git-filter-branch manpage are also affected by this). - BSD vs. GNU userland differences can really bite. If lucky, error - messages are spewed. But just as likely, the commands either don't - do the filtering requested, or silently corrupt by making some - unwanted change. The unwanted change may only affect a few commits, - so it's not necessarily obvious either. (The fact that problems - won't necessarily be obvious means they are likely to go unnoticed - until the rewritten history is in use for quite a while, at which - point it's really hard to justify another flag-day for another - rewrite.) - -* Filenames with spaces are often mishandled by shell snippets since - they cause problems for shell pipelines. Not everyone is familiar - with find -print0, xargs -0, git-ls-files -z, etc. Even people who - are familiar with these may assume such flags are not relevant - because someone else renamed any such files in their repo back - before the person doing the filtering joined the project. And - often, even those familiar with handling arguments with spaces may - not do so just because they aren't in the mindset of thinking about - everything that could possibly go wrong. - -* Non-ascii filenames can be silently removed despite being in a - desired directory. Keeping only wanted paths is often done using - pipelines like `git ls-files | grep -v ^WANTED_DIR/ | xargs git rm`. - ls-files will only quote filenames if needed, so folks may not - notice that one of the files didn't match the regex (at least not - until it's much too late). Yes, someone who knows about - core.quotePath can avoid this (unless they have other special - characters like \t, \n, or "), and people who use ls-files -z with - something other than grep can avoid this, but that doesn't mean they - will. - -* Similarly, when moving files around, one can find that filenames - with non-ascii or special characters end up in a different - directory, one that includes a double quote character. (This is - technically the same issue as above with quoting, but perhaps an - interesting different way that it can and has manifested as a - problem.) - -* It's far too easy to accidentally mix up old and new history. It's - still possible with any tool, but git-filter-branch almost - invites it. If lucky, the only downside is users getting frustrated - that they don't know how to shrink their repo and remove the old - stuff. If unlucky, they merge old and new history and end up with - multiple "copies" of each commit, some of which have unwanted or - sensitive files and others which don't. This comes about in - multiple different ways: - - ** the default to only doing a partial history rewrite ('--all' is not - the default and few examples show it) - - ** the fact that there's no automatic post-run cleanup - - ** the fact that --tag-name-filter (when used to rename tags) doesn't - remove the old tags but just adds new ones with the new name - - ** the fact that little educational information is provided to inform - users of the ramifications of a rewrite and how to avoid mixing old - and new history. For example, this man page discusses how users - need to understand that they need to rebase their changes for all - their branches on top of new history (or delete and reclone), but - that's only one of multiple concerns to consider. See the - "DISCUSSION" section of the git filter-repo manual page for more - details. - -* Annotated tags can be accidentally converted to lightweight tags, - due to either of two issues: - - ** Someone can do a history rewrite, realize they messed up, restore - from the backups in refs/original/, and then redo their - git-filter-branch command. (The backup in refs/original/ is not a - real backup; it dereferences tags first.) - - ** Running git-filter-branch with either --tags or --all in your - <rev-list options>. In order to retain annotated tags as - annotated, you must use --tag-name-filter (and must not have - restored from refs/original/ in a previously botched rewrite). - -* Any commit messages that specify an encoding will become corrupted - by the rewrite; git-filter-branch ignores the encoding, takes the - original bytes, and feeds it to commit-tree without telling it the - proper encoding. (This happens whether or not --msg-filter is - used.) - -* Commit messages (even if they are all UTF-8) by default become - corrupted due to not being updated -- any references to other commit - hashes in commit messages will now refer to no-longer-extant - commits. - -* There are no facilities for helping users find what unwanted crud - they should delete, which means they are much more likely to have - incomplete or partial cleanups that sometimes result in confusion - and people wasting time trying to understand. (For example, folks - tend to just look for big files to delete instead of big directories - or extensions, and once they do so, then sometime later folks using - the new repository who are going through history will notice a build - artifact directory that has some files but not others, or a cache of - dependencies (node_modules or similar) which couldn't have ever been - functional since it's missing some files.) - -* If --prune-empty isn't specified, then the filtering process can - create hoards of confusing empty commits - -* If --prune-empty is specified, then intentionally placed empty - commits from before the filtering operation are also pruned instead - of just pruning commits that became empty due to filtering rules. - -* If --prune-empty is specified, sometimes empty commits are missed - and left around anyway (a somewhat rare bug, but it happens...) - -* A minor issue, but users who have a goal to update all names and - emails in a repository may be led to --env-filter which will only - update authors and committers, missing taggers. - -* If the user provides a --tag-name-filter that maps multiple tags to - the same name, no warning or error is provided; git-filter-branch - simply overwrites each tag in some undocumented pre-defined order - resulting in only one tag at the end. (A git-filter-branch - regression test requires this surprising behavior.) - -Also, the poor performance of git-filter-branch often leads to safety -issues: - -* Coming up with the correct shell snippet to do the filtering you - want is sometimes difficult unless you're just doing a trivial - modification such as deleting a couple files. Unfortunately, people - often learn if the snippet is right or wrong by trying it out, but - the rightness or wrongness can vary depending on special - circumstances (spaces in filenames, non-ascii filenames, funny - author names or emails, invalid timezones, presence of grafts or - replace objects, etc.), meaning they may have to wait a long time, - hit an error, then restart. The performance of git-filter-branch is - so bad that this cycle is painful, reducing the time available to - carefully re-check (to say nothing about what it does to the - patience of the person doing the rewrite even if they do technically - have more time available). This problem is extra compounded because - errors from broken filters may not be shown for a long time and/or - get lost in a sea of output. Even worse, broken filters often just - result in silent incorrect rewrites. - -* To top it all off, even when users finally find working commands, - they naturally want to share them. But they may be unaware that - their repo didn't have some special cases that someone else's does. - So, when someone else with a different repository runs the same - commands, they get hit by the problems above. Or, the user just - runs commands that really were vetted for special cases, but they - run it on a different OS where it doesn't work, as noted above. - -GIT ---- -Part of the linkgit:git[1] suite |