diff options
Diffstat (limited to 'Documentation')
| -rw-r--r-- | Documentation/git-bundle.txt | 147 | ||||
| -rw-r--r-- | Documentation/git-rebase.txt | 27 | ||||
| -rw-r--r-- | Documentation/merge-options.txt | 4 | ||||
| -rw-r--r-- | Documentation/merge-strategies.txt | 48 | ||||
| -rw-r--r-- | Documentation/technical/directory-rename-detection.txt | 14 |
5 files changed, 170 insertions, 70 deletions
diff --git a/Documentation/git-bundle.txt b/Documentation/git-bundle.txt index 53804cad4b..ac0d003835 100644 --- a/Documentation/git-bundle.txt +++ b/Documentation/git-bundle.txt @@ -18,21 +18,48 @@ SYNOPSIS DESCRIPTION ----------- -Some workflows require that one or more branches of development on one -machine be replicated on another machine, but the two machines cannot -be directly connected, and therefore the interactive Git protocols (git, -ssh, http) cannot be used. - -The 'git bundle' command packages objects and references in an archive -at the originating machine, which can then be imported into another -repository using 'git fetch', 'git pull', or 'git clone', -after moving the archive by some means (e.g., by sneakernet). - -As no -direct connection between the repositories exists, the user must specify a -basis for the bundle that is held by the destination repository: the -bundle assumes that all objects in the basis are already in the -destination repository. +Create, unpack, and manipulate "bundle" files. Bundles are used for +the "offline" transfer of Git objects without an active "server" +sitting on the other side of the network connection. + +They can be used to create both incremental and full backups of a +repository, and to relay the state of the references in one repository +to another. + +Git commands that fetch or otherwise "read" via protocols such as +`ssh://` and `https://` can also operate on bundle files. It is +possible linkgit:git-clone[1] a new repository from a bundle, to use +linkgit:git-fetch[1] to fetch from one, and to list the references +contained within it with linkgit:git-ls-remote[1]. There's no +corresponding "write" support, i.e.a 'git push' into a bundle is not +supported. + +See the "EXAMPLES" section below for examples of how to use bundles. + +BUNDLE FORMAT +------------- + +Bundles are `.pack` files (see linkgit:git-pack-objects[1]) with a +header indicating what references are contained within the bundle. + +Like the the packed archive format itself bundles can either be +self-contained, or be created using exclusions. +See the "OBJECT PREREQUISITES" section below. + +Bundles created using revision exclusions are "thin packs" created +using the `--thin` option to linkgit:git-pack-objects[1], and +unbundled using the `--fix-thin` option to linkgit:git-index-pack[1]. + +There is no option to create a "thick pack" when using revision +exclusions, users should not be concerned about the difference. By +using "thin packs" bundles created using exclusions are smaller in +size. That they're "thin" under the hood is merely noted here as a +curiosity, and as a reference to other documentation + +See link:technical/bundle-format.html[the `bundle-format` +documentation] for more details and the discussion of "thin pack" in +link:technical/pack-format.html[the pack format documentation] for +further details. OPTIONS ------- @@ -117,28 +144,88 @@ unbundle <file>:: SPECIFYING REFERENCES --------------------- -'git bundle' will only package references that are shown by -'git show-ref': this includes heads, tags, and remote heads. References -such as `master~1` cannot be packaged, but are perfectly suitable for -defining the basis. More than one reference may be packaged, and more -than one basis can be specified. The objects packaged are those not -contained in the union of the given bases. Each basis can be -specified explicitly (e.g. `^master~10`), or implicitly (e.g. -`master~10..master`, `--since=10.days.ago master`). +Revisions must accompanied by reference names to be packaged in a +bundle. + +More than one reference may be packaged, and more than one set of prerequisite objects can +be specified. The objects packaged are those not contained in the +union of the prerequisites. + +The 'git bundle create' command resolves the reference names for you +using the same rules as `git rev-parse --abbrev-ref=loose`. Each +prerequisite can be specified explicitly (e.g. `^master~10`), or implicitly +(e.g. `master~10..master`, `--since=10.days.ago master`). + +All of these simple cases are OK (assuming we have a "master" and +"next" branch): + +---------------- +$ git bundle create master.bundle master +$ echo master | git bundle create master.bundle --stdin +$ git bundle create master-and-next.bundle master next +$ (echo master; echo next) | git bundle create master-and-next.bundle --stdin +---------------- + +And so are these (and the same but omitted `--stdin` examples): + +---------------- +$ git bundle create recent-master.bundle master~10..master +$ git bundle create recent-updates.bundle master~10..master next~5..next +---------------- + +A revision name or a range whose right-hand-side cannot be resolved to +a reference is not accepted: + +---------------- +$ git bundle create HEAD.bundle $(git rev-parse HEAD) +fatal: Refusing to create empty bundle. +$ git bundle create master-yesterday.bundle master~10..master~5 +fatal: Refusing to create empty bundle. +---------------- + +OBJECT PREREQUISITES +-------------------- + +When creating bundles it is possible to create a self-contained bundle +that can be unbundled in a repository with no common history, as well +as providing negative revisions to exclude objects needed in the +earlier parts of the history. + +Feeding a revision such as `new` to `git bundle create` will create a +bundle file that contains all the objects reachable from the revision +`new`. That bundle can be unbundled in any repository to obtain a full +history that leads to the revision `new`: + +---------------- +$ git bundle create full.bundle new +---------------- + +A revision range such as `old..new` will produce a bundle file that +will require the revision `old` (and any objects reachable from it) +to exist for the bundle to be "unbundle"-able: + +---------------- +$ git bundle create full.bundle old..new +---------------- + +A self-contained bundle without any prerequisites can be extracted +into anywhere, even into an empty repository, or be cloned from +(i.e., `new`, but not `old..new`). -It is very important that the basis used be held by the destination. It is okay to err on the side of caution, causing the bundle file to contain objects already in the destination, as these are ignored when unpacking at the destination. -`git clone` can use any bundle created without negative refspecs -(e.g., `new`, but not `old..new`). If you want to match `git clone --mirror`, which would include your refs such as `refs/remotes/*`, use `--all`. If you want to provide the same set of refs that a clone directly from the source repository would get, use `--branches --tags` for the `<git-rev-list-args>`. +The 'git bundle verify' command can be used to check whether your +recipient repository has the required prerequisite commits for a +bundle. + EXAMPLES -------- @@ -149,7 +236,7 @@ but we can move data from A to B via some mechanism (CD, email, etc.). We want to update R2 with development made on the branch master in R1. To bootstrap the process, you can first create a bundle that does not have -any basis. You can use a tag to remember up to what commit you last +any prerequisites. You can use a tag to remember up to what commit you last processed, in order to make it easy to later update the other repository with an incremental bundle: @@ -200,7 +287,7 @@ machineB$ git pull If you know up to what commit the intended recipient repository should have the necessary objects, you can use that knowledge to specify the -basis, giving a cut-off point to limit the revisions and objects that go +prerequisites, giving a cut-off point to limit the revisions and objects that go in the resulting bundle. The previous example used the lastR2bundle tag for this purpose, but you can use any other options that you would give to the linkgit:git-log[1] command. Here are more examples: @@ -211,7 +298,7 @@ You can use a tag that is present in both: $ git bundle create mybundle v1.0.0..master ---------------- -You can use a basis based on time: +You can use a prerequisite based on time: ---------------- $ git bundle create mybundle --since=10.days master @@ -224,7 +311,7 @@ $ git bundle create mybundle -10 master ---------------- You can run `git-bundle verify` to see if you can extract from a bundle -that was created with a basis: +that was created with a prerequisite: ---------------- $ git bundle verify mybundle diff --git a/Documentation/git-rebase.txt b/Documentation/git-rebase.txt index 55af6fd24e..73d49ec8d9 100644 --- a/Documentation/git-rebase.txt +++ b/Documentation/git-rebase.txt @@ -340,9 +340,7 @@ See also INCOMPATIBLE OPTIONS below. -m:: --merge:: - Use merging strategies to rebase. When the recursive (default) merge - strategy is used, this allows rebase to be aware of renames on the - upstream side. This is the default. + Using merging strategies to rebase (default). + Note that a rebase merge works by replaying each commit from the working branch on top of the <upstream> branch. Because of this, when a merge @@ -354,9 +352,8 @@ See also INCOMPATIBLE OPTIONS below. -s <strategy>:: --strategy=<strategy>:: - Use the given merge strategy. - If there is no `-s` option 'git merge-recursive' is used - instead. This implies --merge. + Use the given merge strategy, instead of the default + `recursive`. This implies `--merge`. + Because 'git rebase' replays each commit from the working branch on top of the <upstream> branch using the given strategy, using @@ -530,7 +527,7 @@ The `--rebase-merges` mode is similar in spirit to the deprecated where commits can be reordered, inserted and dropped at will. + It is currently only possible to recreate the merge commits using the -`recursive` merge strategy; Different merge strategies can be used only via +`recursive` merge strategy; different merge strategies can be used only via explicit `exec git merge -s <strategy> [...]` commands. + See also REBASING MERGES and INCOMPATIBLE OPTIONS below. @@ -1219,12 +1216,16 @@ successful merge so that the user can edit the message. If a `merge` command fails for any reason other than merge conflicts (i.e. when the merge operation did not even start), it is rescheduled immediately. -At this time, the `merge` command will *always* use the `recursive` -merge strategy for regular merges, and `octopus` for octopus merges, -with no way to choose a different one. To work around -this, an `exec` command can be used to call `git merge` explicitly, -using the fact that the labels are worktree-local refs (the ref -`refs/rewritten/onto` would correspond to the label `onto`, for example). +By default, the `merge` command will use the `recursive` merge +strategy for regular merges, and `octopus` for octopus merges. One +can specify a default strategy for all merges using the `--strategy` +argument when invoking rebase, or can override specific merges in the +interactive list of commands by using an `exec` command to call `git +merge` explicitly with a `--strategy` argument. Note that when +calling `git merge` explicitly like this, you can make use of the fact +that the labels are worktree-local refs (the ref `refs/rewritten/onto` +would correspond to the label `onto`, for example) in order to refer +to the branches you want to merge. Note: the first command (`label onto`) labels the revision onto which the commits are rebased; The name `onto` is just a convention, as a nod diff --git a/Documentation/merge-options.txt b/Documentation/merge-options.txt index 52565014c1..f66e650064 100644 --- a/Documentation/merge-options.txt +++ b/Documentation/merge-options.txt @@ -112,8 +112,8 @@ With --squash, --commit is not allowed, and will fail. Use the given merge strategy; can be supplied more than once to specify them in the order they should be tried. If there is no `-s` option, a built-in list of strategies - is used instead ('git merge-recursive' when merging a single - head, 'git merge-octopus' otherwise). + is used instead (`recursive` when merging a single head, + `octopus` otherwise). -X <option>:: --strategy-option=<option>:: diff --git a/Documentation/merge-strategies.txt b/Documentation/merge-strategies.txt index 2912de706b..210f0f850b 100644 --- a/Documentation/merge-strategies.txt +++ b/Documentation/merge-strategies.txt @@ -6,13 +6,6 @@ backend 'merge strategies' to be chosen with `-s` option. Some strategies can also take their own options, which can be passed by giving `-X<option>` arguments to `git merge` and/or `git pull`. -resolve:: - This can only resolve two heads (i.e. the current branch - and another branch you pulled from) using a 3-way merge - algorithm. It tries to carefully detect criss-cross - merge ambiguities and is considered generally safe and - fast. - recursive:: This can only resolve two heads using a 3-way merge algorithm. When there is more than one common @@ -23,9 +16,9 @@ recursive:: causing mismerges by tests done on actual merge commits taken from Linux 2.6 kernel development history. Additionally this can detect and handle merges involving - renames, but currently cannot make use of detected - copies. This is the default merge strategy when pulling - or merging one branch. + renames. It does not make use of detected copies. This + is the default merge strategy when pulling or merging one + branch. + The 'recursive' strategy can take the following options: @@ -44,17 +37,14 @@ theirs;; no 'theirs' merge strategy to confuse this merge option with. patience;; - With this option, 'merge-recursive' spends a little extra time - to avoid mismerges that sometimes occur due to unimportant - matching lines (e.g., braces from distinct functions). Use - this when the branches to be merged have diverged wildly. - See also linkgit:git-diff[1] `--patience`. + Deprecated synonym for `diff-algorithm=patience`. diff-algorithm=[patience|minimal|histogram|myers];; - Tells 'merge-recursive' to use a different diff algorithm, which - can help avoid mismerges that occur due to unimportant matching - lines (such as braces from distinct functions). See also - linkgit:git-diff[1] `--diff-algorithm`. + Use a different diff algorithm while merging, which can help + avoid mismerges that occur due to unimportant matching lines + (such as braces from distinct functions). See also + linkgit:git-diff[1] `--diff-algorithm`. Defaults to the + `diff.algorithm` config setting. ignore-space-change;; ignore-all-space;; @@ -105,6 +95,26 @@ subtree[=<path>];; is prefixed (or stripped from the beginning) to make the shape of two trees to match. +ort:: + This is meant as a drop-in replacement for the `recursive` + algorithm (as reflected in its acronym -- "Ostensibly + Recursive's Twin"), and will likely replace it in the future. + It fixes corner cases that the `recursive` strategy handles + suboptimally, and is significantly faster in large + repositories -- especially when many renames are involved. ++ +The `ort` strategy takes all the same options as `recursive`. +However, it ignores three of those options: `no-renames`, +`patience` and `diff-algorithm`. It always runs with rename +detection (it handles it much faster than `recursive` does), and +it specifically uses `diff-algorithm=histogram`. + +resolve:: + This can only resolve two heads (i.e. the current branch + and another branch you pulled from) using a 3-way merge + algorithm. It tries to carefully detect criss-cross + merge ambiguities. It does not handle renames. + octopus:: This resolves cases with more than two heads, but refuses to do a complex merge that needs manual resolution. It is diff --git a/Documentation/technical/directory-rename-detection.txt b/Documentation/technical/directory-rename-detection.txt index 49b83ef3cc..029ee2cedc 100644 --- a/Documentation/technical/directory-rename-detection.txt +++ b/Documentation/technical/directory-rename-detection.txt @@ -2,9 +2,9 @@ Directory rename detection ========================== Rename detection logic in diffcore-rename that checks for renames of -individual files is aggregated and analyzed in merge-recursive for cases -where combinations of renames indicate that a full directory has been -renamed. +individual files is also aggregated there and then analyzed in either +merge-ort or merge-recursive for cases where combinations of renames +indicate that a full directory has been renamed. Scope of abilities ------------------ @@ -88,9 +88,11 @@ directory rename detection support in: Folks have requested in the past that `git diff` detect directory renames and somehow simplify its output. It is not clear whether this would be desirable or how the output should be simplified, so this was - simply not implemented. Further, to implement this, directory rename - detection logic would need to move from merge-recursive to - diffcore-rename. + simply not implemented. Also, while diffcore-rename has most of the + logic for detecting directory renames, some of the logic is still found + within merge-ort and merge-recursive. Fully supporting directory + rename detection in diffs would require copying or moving the remaining + bits of logic to the diff machinery. * am |