mirror of
https://github.com/git/git.git
synced 2024-05-29 02:46:38 +02:00
Minor clarifications in diffcore documentation
Signed-off-by: Chris Shoemaker <c.shoemaker at cox.net> Signed-off-by: Junio C Hamano <junkio@cox.net>
This commit is contained in:
c.shoemaker@cox.net
Junio C Hamano
parent
1cb7f22e5c
commit
59df2a11fe
|
|
@ -6,13 +6,12 @@ June 2005
|
|||
Introduction
|
||||
------------
|
||||
|
||||
The diff commands git-diff-index, git-diff-files, and
|
||||
git-diff-tree can be told to manipulate differences they find
|
||||
in unconventional ways before showing diff(1) output. The
|
||||
manipulation is collectively called "diffcore transformation".
|
||||
This short note describes what they are and how to use them to
|
||||
produce diff outputs that are easier to understand than the
|
||||
conventional kind.
|
||||
The diff commands git-diff-index, git-diff-files, git-diff-tree, and
|
||||
git-diff-stages can be told to manipulate differences they find in
|
||||
unconventional ways before showing diff(1) output. The manipulation
|
||||
is collectively called "diffcore transformation". This short note
|
||||
describes what they are and how to use them to produce diff outputs
|
||||
that are easier to understand than the conventional kind.
|
||||
|
||||
|
||||
The chain of operation
|
||||
|
|
@ -29,7 +28,10 @@ files:
|
|||
- git-diff-files compares contents of the index file and the
|
||||
working directory;
|
||||
|
||||
- git-diff-tree compares contents of two "tree" objects.
|
||||
- git-diff-tree compares contents of two "tree" objects;
|
||||
|
||||
- git-diff-stages compares contents of blobs at two stages in an
|
||||
unmerged index file.
|
||||
|
||||
In all of these cases, the commands themselves compare
|
||||
corresponding paths in the two sets of files. The result of
|
||||
|
|
@ -65,14 +67,23 @@ format sections of the manual for git-diff-\* commands) or
|
|||
diff-patch format.
|
||||
|
||||
|
||||
diffcore-pathspec
|
||||
diffcore-pathspec: For Ignoring Files Outside Our Consideration
|
||||
-----------------
|
||||
|
||||
The first transformation in the chain is diffcore-pathspec, and
|
||||
is controlled by giving the pathname parameters to the
|
||||
git-diff-* commands on the command line. The pathspec is used
|
||||
to limit the world diff operates in. It removes the filepairs
|
||||
outside the specified set of pathnames.
|
||||
outside the specified set of pathnames. E.g. If the input set
|
||||
of filepairs included:
|
||||
|
||||
------------------------------------------------
|
||||
:100644 100644 bcd1234... 0123456... M junkfile
|
||||
------------------------------------------------
|
||||
|
||||
but the command invocation was "git-diff-files myfile", then the
|
||||
junkfile entry would be removed from the list because only "myfile"
|
||||
is under consideration.
|
||||
|
||||
Implementation note. For performance reasons, git-diff-tree
|
||||
uses the pathname parameters on the command line to cull set of
|
||||
|
|
@ -80,7 +91,7 @@ filepairs it feeds the diffcore mechanism itself, and does not
|
|||
use diffcore-pathspec, but the end result is the same.
|
||||
|
||||
|
||||
diffcore-break
|
||||
diffcore-break: For Splitting Up "Complete Rewrites"
|
||||
--------------
|
||||
|
||||
The second transformation in the chain is diffcore-break, and is
|
||||
|
|
@ -115,7 +126,7 @@ the original is used), and can be customized by giving a number
|
|||
after "-B" option (e.g. "-B75" to tell it to use 75%).
|
||||
|
||||
|
||||
diffcore-rename
|
||||
diffcore-rename: For Detection Renames and Copies
|
||||
---------------
|
||||
|
||||
This transformation is used to detect renames and copies, and is
|
||||
|
|
@ -136,16 +147,16 @@ merges these filepairs and creates:
|
|||
:100644 100644 0123456... 0123456... R100 fileX file0
|
||||
------------------------------------------------
|
||||
|
||||
When the "-C" option is used, the original contents of modified
|
||||
files and contents of unchanged files are considered as
|
||||
candidates of the source files in rename/copy operation, in
|
||||
addition to the deleted files. If the input were like these
|
||||
filepairs, that talk about a modified file fileY and a newly
|
||||
When the "-C" option is used, the original contents of modified files,
|
||||
and deleted files (and also unmodified files, if the
|
||||
"\--find-copies-harder" option is used) are considered as candidates
|
||||
of the source files in rename/copy operation. If the input were like
|
||||
these filepairs, that talk about a modified file fileY and a newly
|
||||
created file file0:
|
||||
|
||||
------------------------------------------------
|
||||
:100644 100644 0123456... 1234567... M fileY
|
||||
:000000 100644 0000000... 0123456... A file0
|
||||
:000000 100644 0000000... bcd3456... A file0
|
||||
------------------------------------------------
|
||||
|
||||
the original contents of fileY and the resulting contents of
|
||||
|
|
@ -154,14 +165,14 @@ changed to:
|
|||
|
||||
------------------------------------------------
|
||||
:100644 100644 0123456... 1234567... M fileY
|
||||
:100644 100644 0123456... 0123456... C100 fileY file0
|
||||
:100644 100644 0123456... bcd3456... C100 fileY file0
|
||||
------------------------------------------------
|
||||
|
||||
In both rename and copy detection, the same "extent of changes"
|
||||
algorithm used in diffcore-break is used to determine if two
|
||||
files are "similar enough", and can be customized to use
|
||||
similarity score different from the default 50% by giving a
|
||||
number after "-M" or "-C" option (e.g. "-M8" to tell it to use
|
||||
a similarity score different from the default of 50% by giving a
|
||||
number after the "-M" or "-C" option (e.g. "-M8" to tell it to use
|
||||
8/10 = 80%).
|
||||
|
||||
Note. When the "-C" option is used with `\--find-copies-harder`
|
||||
|
|
@ -173,7 +184,7 @@ git-diff-\* commands can detect copies only if the file that was
|
|||
copied happened to have been modified in the same changeset.
|
||||
|
||||
|
||||
diffcore-merge-broken
|
||||
diffcore-merge-broken: For Putting "Complete Rewrites" Back Together
|
||||
---------------------
|
||||
|
||||
This transformation is used to merge filepairs broken by
|
||||
|
|
@ -215,7 +226,7 @@ prefixed with '-', followed by the entire contents of new
|
|||
version prefixed with '+'.
|
||||
|
||||
|
||||
diffcore-pickaxe
|
||||
diffcore-pickaxe: For Detecting Addition/Deletion of Specified String
|
||||
----------------
|
||||
|
||||
This transformation is used to find filepairs that represent
|
||||
|
|
@ -230,7 +241,7 @@ string appeared in this changeset". It also checks for the
|
|||
opposite case that loses the specified string.
|
||||
|
||||
When `\--pickaxe-all` is not in effect, diffcore-pickaxe leaves
|
||||
only such filepairs that touches the specified string in its
|
||||
only such filepairs that touch the specified string in its
|
||||
output. When `\--pickaxe-all` is used, diffcore-pickaxe leaves all
|
||||
filepairs intact if there is such a filepair, or makes the
|
||||
output empty otherwise. The latter behaviour is designed to
|
||||
|
|
@ -238,19 +249,19 @@ make reviewing of the changes in the context of the whole
|
|||
changeset easier.
|
||||
|
||||
|
||||
diffcore-order
|
||||
diffcore-order: For Sorting the Output Based on Filenames
|
||||
--------------
|
||||
|
||||
This is used to reorder the filepairs according to the user's
|
||||
(or project's) taste, and is controlled by the -O option to the
|
||||
git-diff-* commands.
|
||||
|
||||
This takes a text file each of whose line is a shell glob
|
||||
This takes a text file each of whose lines is a shell glob
|
||||
pattern. Filepairs that match a glob pattern on an earlier line
|
||||
in the file are output before ones that match a later line, and
|
||||
filepairs that do not match any glob pattern are output last.
|
||||
|
||||
As an example, typical orderfile for the core git probably
|
||||
As an example, a typical orderfile for the core git probably
|
||||
would look like this:
|
||||
|
||||
------------------------------------------------
|
||||
|
|
|
|||
Loading…
Reference in New Issue