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GIT-PATCH-ID(1)                    Git Manual                   GIT-PATCH-ID(1)

NAME
       git-patch-id - Compute unique ID for a patch

SYNOPSIS
       git patch-id [--stable | --unstable | --verbatim]

DESCRIPTION
       Read a patch from the standard input and compute the patch ID for it.

       A "patch ID" is nothing but a sum of SHA-1 of the file diffs associated
       with a patch, with line numbers ignored. As such, it’s "reasonably
       stable", but at the same time also reasonably unique, i.e., two patches
       that have the same "patch ID" are almost guaranteed to be the same
       thing.

       The main usecase for this command is to look for likely duplicate
       commits.

       When dealing with git diff-tree output, it takes advantage of the fact
       that the patch is prefixed with the object name of the commit, and
       outputs two 40-byte hexadecimal strings. The first string is the patch
       ID, and the second string is the commit ID. This can be used to make a
       mapping from patch ID to commit ID.

OPTIONS
       --verbatim
           Calculate the patch-id of the input as it is given, do not strip any
           whitespace.

               This is the default if patchid.verbatim is true.

       --stable
           Use a "stable" sum of hashes as the patch ID. With this option:

           •   Reordering file diffs that make up a patch does not affect the
               ID. In particular, two patches produced by comparing the same
               two trees with two different settings for "-O<orderfile>" result
               in the same patch ID signature, thereby allowing the computed
               result to be used as a key to index some meta-information about
               the change between the two trees;

           •   Result is different from the value produced by git 1.9 and older
               or produced when an "unstable" hash (see --unstable below) is
               configured - even when used on a diff output taken without any
               use of "-O<orderfile>", thereby making existing databases
               storing such "unstable" or historical patch-ids unusable.

           •   All whitespace within the patch is ignored and does not affect
               the id.

                   This is the default if patchid.stable is set to true.

       --unstable
           Use an "unstable" hash as the patch ID. With this option, the result
           produced is compatible with the patch-id value produced by git 1.9
           and older and whitespace is ignored. Users with pre-existing
           databases storing patch-ids produced by git 1.9 and older (who do
           not deal with reordered patches) may want to use this option.

               This is the default.

GIT
       Part of the git(1) suite

Git 2.47.3                         07/30/2025                   GIT-PATCH-ID(1)

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