GIT-MERGETOOL
Section: Git Manual (1)
Updated: 202-0-01
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NAME
gi-mergetool - Run merge conflict resolution tools to resolve merge conflicts
SYNOPSIS
git mergetool [--tool=<tool>] [-y | --[no-]prompt] [<file>...:]
DESCRIPTION
Use git mergetool to run one of several merge utilities to resolve merge conflicts. It is typically run after git merge.
If one or more <file> parameters are given, the merge tool program will be run to resolve differences in each file (skipping those without conflicts). Specifying a directory will include all unresolved files in that path. If no <file> names are specified, git mergetool will run the merge tool program on every file with merge conflicts.
OPTIONS
-t <tool>, --tool=<tool>
-
Use the merge resolution program specified by
<tool>. Valid values include
emerge,
gvimdiff,
kdiff3,
meld,
vimdiff, and
tortoisemerge. Run
git
mergetool
--tool-help
for the list of valid
<tool>
settings.
If a merge resolution program is not specified,
git
mergetool
will use the configuration variable
merge.tool. If the configuration variable
merge.tool
is not set,
git
mergetool
will pick a suitable default.
You can explicitly provide a full path to the tool by setting the configuration variable
mergetool.<tool>.path. For example, you can configure the absolute path to kdiff3 by setting
mergetool.kdiff3.path. Otherwise,
git
mergetool
assumes the tool is available in
$PATH.
Instead of running one of the known merge tool programs,
git
mergetool
can be customized to run an alternative program by specifying the command line to invoke in a configuration variable
mergetool.<tool>.cmd.
When
git
mergetool
is invoked with this tool (either through the
-t
or
--tool
option or the
merge.tool
configuration variable), the configured command line will be invoked with
BASE
set to the name of a temporary file containing the common base for the merge, if available;
LOCAL
set to the name of a temporary file containing the contents of the file on the current branch;
REMOTE
set to the name of a temporary file containing the contents of the file to be merged, and
MERGED
set to the name of the file to which the merge tool should write the result of the merge resolution.
If the custom merge tool correctly indicates the success of a merge resolution with its exit code, then the configuration variable
mergetool.<tool>.trustExitCode
can be set to
true. Otherwise,
git
mergetool
will prompt the user to indicate the success of the resolution after the custom tool has exited.
--tool-help
-
Print a list of merge tools that may be used with
--tool.
-y, --no-prompt
-
Doncqt prompt before each invocation of the merge resolution program. This is the default if the merge resolution program is explicitly specified with the
--tool
option or with the
merge.tool
configuration variable.
--prompt
-
Prompt before each invocation of the merge resolution program to give the user a chance to skip the path.
-g, --gui
-
When
git-mergetool
is invoked with the
-g
or
--gui
option, the default merge tool will be read from the configured
merge.guitool
variable instead of
merge.tool. If
merge.guitool
is not set, we will fallback to the tool configured under
merge.tool. This may be autoselected using the configuration variable
mergetool.guiDefault.
--no-gui
-
This overrides a previous
-g
or
--gui
setting or
mergetool.guiDefault
configuration and reads the default merge tool from the configured
merge.tool
variable.
-O<orderfile>
-
Process files in the order specified in the
<orderfile>, which has one shell glob pattern per line. This overrides the
diff.orderFile
configuration variable (see
gi-config(1)). To cancel
diff.orderFile, use
-O/dev/null.
CONFIGURATION
Everything below this line in this section is selectively included from the gi-config(1) documentation. The content is the same as whatcqs found there:
mergetool.<tool>.path
-
Override the path for the given tool. This is useful in case your tool is not in the
$PATH.
mergetool.<tool>.cmd
-
Specify the command to invoke the specified merge tool. The specified command is evaluated in shell with the following variables available:
BASE
is the name of a temporary file containing the common base of the files to be merged, if available;
LOCAL
is the name of a temporary file containing the contents of the file on the current branch;
REMOTE
is the name of a temporary file containing the contents of the file from the branch being merged;
MERGED
contains the name of the file to which the merge tool should write the results of a successful merge.
mergetool.<tool>.hideResolved
-
Allows the user to override the global
mergetool.hideResolved
value for a specific tool. See
mergetool.hideResolved
for the full description.
mergetool.<tool>.trustExitCode
-
For a custom merge command, specify whether the exit code of the merge command can be used to determine whether the merge was successful. If this is not set to true then the merge target file timestamp is checked, and the merge is assumed to have been successful if the file has been updated; otherwise, the user is prompted to indicate the success of the merge.
mergetool.meld.hasOutput
-
Older versions of
meld
do not support the
--output
option. Git will attempt to detect whether
meld
supports
--output
by inspecting the output of
meld
--help. Configuring
mergetool.meld.hasOutput
will make Git skip these checks and use the configured value instead. Setting
mergetool.meld.hasOutput
to
true
tells Git to unconditionally use the
--output
option, and
false
avoids using
--output.
mergetool.meld.useAutoMerge
-
When the
--auto-merge
is given, meld will merge all non-conflicting parts automatically, highlight the conflicting parts, and wait for user decision. Setting
mergetool.meld.useAutoMerge
to
true
tells Git to unconditionally use the
--auto-merge
option with
meld. Setting this value to
auto
makes git detect whether
--auto-merge
is supported and will only use
--auto-merge
when available. A value of
false
avoids using
--auto-merge
altogether, and is the default value.
mergetool.<variant>.layout
-
Configure the split window layout for vimdiffcqs
<variant>, which is any of
vimdiff,
nvimdiff,
gvimdiff. Upon launching
git
mergetool
with
--tool=<variant>
(or without
--tool
if
merge.tool
is configured as
<variant>), Git will consult
mergetool.<variant>.layout
to determine the toolcqs layout. If the variant-specific configuration is not available,
vimdiff
' s is used as fallback. If that too is not available, a default layout with 4 windows will be used. To configure the layout, see the
BACKEND SPECIFIC HINTS
section.
mergetool.hideResolved
-
During a merge, Git will automatically resolve as many conflicts as possible and write the
$MERGED
file containing conflict markers around any conflicts that it cannot resolve;
$LOCAL
and
$REMOTE
normally are the versions of the file from before Gitcqs conflict resolution. This flag causes
$LOCAL
and
$REMOTE
to be overwritten so that only the unresolved conflicts are presented to the merge tool. Can be configured per-tool via the
mergetool.<tool>.hideResolved
configuration variable. Defaults to
false.
mergetool.keepBackup
-
After performing a merge, the original file with conflict markers can be saved as a file with a .orig
extension. If this variable is set to
false
then this file is not preserved. Defaults to
true
(i.e. keep the backup files).
mergetool.keepTemporaries
-
When invoking a custom merge tool, Git uses a set of temporary files to pass to the tool. If the tool returns an error and this variable is set to
true, then these temporary files will be preserved; otherwise, they will be removed after the tool has exited. Defaults to
false.
mergetool.writeToTemp
-
Git writes temporary
BASE,
LOCAL, and
REMOTE
versions of conflicting files in the worktree by default. Git will attempt to use a temporary directory for these files when set
true. Defaults to
false.
mergetool.prompt
-
Prompt before each invocation of the merge resolution program.
mergetool.guiDefault
-
Set
true
to use the
merge.guitool
by default (equivalent to specifying the
--gui
argument), or
auto
to select
merge.guitool
or
merge.tool
depending on the presence of a
DISPLAY
environment variable value. The default is
false, where the
--gui
argument must be provided explicitly for the
merge.guitool
to be used.
TEMPORARY FILES
git mergetool creates *.orig backup files while resolving merges. These are safe to remove once a file has been merged and its git mergetool session has completed.
Setting the mergetool.keepBackup configuration variable to false causes git mergetool to automatically remove the backup files as files are successfully merged.
BACKEND SPECIFIC HINTS
vimdiff
Description
-
When specifying --tool=vimdiff in git mergetool Git will open Vim with a 4 windows layout distributed in the following way:
-
------------------------------------------
| | | |
| LOCAL | BASE | REMOTE |
| | | |
------------------------------------------
| |
| MERGED |
| |
------------------------------------------
LOCAL, BASE and REMOTE are read-only buffers showing the contents of the conflicting file in specific commits ("commit you are merging into", "common ancestor commit" and "commit you are merging from" respectively)
MERGED is a writable buffer where you have to resolve the conflicts (using the other read-only buffers as a reference). Once you are done, save and exit Vim as usual (:wq) or, if you want to abort, exit using :cq.
Layout configuration
-
You can change the windows layout used by Vim by setting configuration variable mergetool.vimdiff.layout which accepts a string where the following separators have special meaning:
-
*
+
is used to "open a new tab"
-
*
,
is used to "open a new vertical split"
-
*
/
is used to "open a new horizontal split"
-
*
@
is used to indicate the file containing the final version after solving the conflicts. If not present,
MERGED
will be used by default.
The precedence of the operators is as follows (you can use parentheses to change it):
-
`@` > `+` > `/` > `,`
Letcqs see some examples to understand how it works:
-
*
layout
=
"(LOCAL,BASE,REMOTE)/MERGED"
This is exactly the same as the default layout we have already seen.
Note that
/
has precedence over
,
and thus the parenthesis are not needed in this case. The next layout definition is equivalent:
-
layout = "LOCAL,BASE,REMOTE / MERGED"
-
*
layout
=
"LOCAL,MERGED,REMOTE"
If, for some reason, we are not interested in the
BASE
buffer.
-
------------------------------------------
| | | |
| | | |
| LOCAL | MERGED | REMOTE |
| | | |
| | | |
------------------------------------------
-
*
layout
=
"MERGED"
Only the
MERGED
buffer will be shown. Note, however, that all the other ones are still loaded in vim, and you can access them with the "buffers" command.
-
------------------------------------------
| |
| |
| MERGED |
| |
| |
------------------------------------------
-
*
layout
=
"@LOCAL,REMOTE"
When
MERGED
is not present in the layout, you must "mark" one of the buffers with an arobase (@). That will become the buffer you need to edit and save after resolving the conflicts.
-
------------------------------------------
| | |
| | |
| | |
| LOCAL | REMOTE |
| | |
| | |
| | |
------------------------------------------
-
*
layout
=
"LOCAL,BASE,REMOTE
/
MERGED
+
BASE,LOCAL
+
BASE,REMOTE"
Three tabs will open: the first one is a copy of the default layout, while the other two only show the differences between (BASE
and
LOCAL) and (BASE
and
REMOTE) respectively.
-
------------------------------------------
| <TAB #1> | TAB #2 | TAB #3 | |
------------------------------------------
| | | |
| LOCAL | BASE | REMOTE |
| | | |
------------------------------------------
| |
| MERGED |
| |
------------------------------------------
-
------------------------------------------
| TAB #1 | <TAB #2> | TAB #3 | |
------------------------------------------
| | |
| | |
| | |
| BASE | LOCAL |
| | |
| | |
| | |
------------------------------------------
-
------------------------------------------
| TAB #1 | TAB #2 | <TAB #3> | |
------------------------------------------
| | |
| | |
| | |
| BASE | REMOTE |
| | |
| | |
| | |
------------------------------------------
-
*
layout
=
"LOCAL,BASE,REMOTE
/
MERGED
+
BASE,LOCAL
+
BASE,REMOTE
+
(LOCAL/BASE/REMOTE),MERGED"
Same as the previous example, but adds a fourth tab with the same information as the first tab, with a different layout.
-
---------------------------------------------
| TAB #1 | TAB #2 | TAB #3 | <TAB #4> |
---------------------------------------------
| LOCAL | |
|---------------------| |
| BASE | MERGED |
|---------------------| |
| REMOTE | |
---------------------------------------------
Note how in the third tab definition we need to use parentheses to make
,
have precedence over
/.
Variants
-
Instead of --tool=vimdiff, you can also use one of these other variants:
-
*
--tool=gvimdiff, to open gVim instead of Vim.
-
*
--tool=nvimdiff, to open Neovim instead of Vim.
When using these variants, in order to specify a custom layout you will have to set configuration variables mergetool.gvimdiff.layout and mergetool.nvimdiff.layout instead of mergetool.vimdiff.layout (though the latter will be used as fallback if the variant-specific one is not set).
In addition, for backwards compatibility with previous Git versions, you can also append 1, 2 or 3 to either vimdiff or any of the variants (ex: vimdiff3, nvimdiff1, etc...:) to use a predefined layout. In other words, using --tool=[g|n]vimdiff<x> is the same as using --tool=[g|n]vimdiff and setting configuration variable mergetool.[g|n]vimdiff.layout to...:
-
*
<x>=1: "@LOCAL,
REMOTE"
-
*
<x>=2: "LOCAL,
MERGED,
REMOTE"
-
*
<x>=3: "MERGED"
Example: using --tool=gvimdiff2 will open gvim with three columns (LOCAL, MERGED and REMOTE).
GIT
Part of the git(1) suite
Index
- NAME
-
- SYNOPSIS
-
- DESCRIPTION
-
- OPTIONS
-
- CONFIGURATION
-
- TEMPORARY FILES
-
- BACKEND SPECIFIC HINTS
-
- vimdiff
-
- GIT
-
|
|
- Running on 
-
:
