git-log - Show commit logs


   git log [<options>] [<revision range>] [[--] <path>...]


   Shows the commit logs.

   The command takes options applicable to the git rev-list command to
   control what is shown and how, and options applicable to the git diff-*
   commands to control how the changes each commit introduces are shown.


       Continue listing the history of a file beyond renames (works only
       for a single file).

   --no-decorate, --decorate[=short|full|auto|no]
       Print out the ref names of any commits that are shown. If short is
       specified, the ref name prefixes refs/heads/, refs/tags/ and
       refs/remotes/ will not be printed. If full is specified, the full
       ref name (including prefix) will be printed. If auto is specified,
       then if the output is going to a terminal, the ref names are shown
       as if short were given, otherwise no ref names are shown. The
       default option is short.

       Print out the ref name given on the command line by which each
       commit was reached.

       Use mailmap file to map author and committer names and email
       addresses to canonical real names and email addresses. See git-

       Without this flag, git log -p <path>...  shows commits that touch
       the specified paths, and diffs about the same specified paths. With
       this, the full diff is shown for commits that touch the specified
       paths; this means that "<path>..." limits only commits, and doesn't
       limit diff for those commits.

       Note that this affects all diff-based output types, e.g. those
       produced by --stat, etc.

       Include a line "log size <number>" in the output for each commit,
       where <number> is the length of that commit's message in bytes.
       Intended to speed up tools that read log messages from git log
       output by allowing them to allocate space in advance.

   -L <start>,<end>:<file>, -L :<funcname>:<file>
       Trace the evolution of the line range given by "<start>,<end>" (or
       the function name regex <funcname>) within the <file>. You may not
       give any pathspec limiters. This is currently limited to a walk
       starting from a single revision, i.e., you may only give zero or
       one positive revision arguments. You can specify this option more
       than once.

       <start> and <end> can take one of these forms:

       *   number

           If <start> or <end> is a number, it specifies an absolute line
           number (lines count from 1).

       *   /regex/

           This form will use the first line matching the given POSIX
           regex. If <start> is a regex, it will search from the end of
           the previous -L range, if any, otherwise from the start of
           file. If <start> is "^/regex/", it will search from the start
           of file. If <end> is a regex, it will search starting at the
           line given by <start>.

       *   +offset or -offset

           This is only valid for <end> and will specify a number of lines
           before or after the line given by <start>.

       If ":<funcname>" is given in place of <start> and <end>, it is a
       regular expression that denotes the range from the first funcname
       line that matches <funcname>, up to the next funcname line.
       ":<funcname>" searches from the end of the previous -L range, if
       any, otherwise from the start of file. "^:<funcname>" searches from
       the start of file.

   <revision range>
       Show only commits in the specified revision range. When no
       <revision range> is specified, it defaults to HEAD (i.e. the whole
       history leading to the current commit).  origin..HEAD specifies all
       the commits reachable from the current commit (i.e.  HEAD), but not
       from origin. For a complete list of ways to spell <revision range>,
       see the Specifying Ranges section of gitrevisions(7).

   [--] <path>...
       Show only commits that are enough to explain how the files that
       match the specified paths came to be. See History Simplification
       below for details and other simplification modes.

       Paths may need to be prefixed with '`-- '' to separate them from
       options or the revision range, when confusion arises.

   Commit Limiting
   Besides specifying a range of commits that should be listed using the
   special notations explained in the description, additional commit
   limiting may be applied.

   Using more options generally further limits the output (e.g.
   --since=<date1> limits to commits newer than <date1>, and using it with
   --grep=<pattern> further limits to commits whose log message has a line
   that matches <pattern>), unless otherwise noted.

   Note that these are applied before commit ordering and formatting
   options, such as --reverse.

   -<number>, -n <number>, --max-count=<number>
       Limit the number of commits to output.

       Skip number commits before starting to show the commit output.

   --since=<date>, --after=<date>
       Show commits more recent than a specific date.

   --until=<date>, --before=<date>
       Show commits older than a specific date.

   --author=<pattern>, --committer=<pattern>
       Limit the commits output to ones with author/committer header lines
       that match the specified pattern (regular expression). With more
       than one --author=<pattern>, commits whose author matches any of
       the given patterns are chosen (similarly for multiple

       Limit the commits output to ones with reflog entries that match the
       specified pattern (regular expression). With more than one
       --grep-reflog, commits whose reflog message matches any of the
       given patterns are chosen. It is an error to use this option unless
       --walk-reflogs is in use.

       Limit the commits output to ones with log message that matches the
       specified pattern (regular expression). With more than one
       --grep=<pattern>, commits whose message matches any of the given
       patterns are chosen (but see --all-match).

       When --show-notes is in effect, the message from the notes is
       matched as if it were part of the log message.

       Limit the commits output to ones that match all given --grep,
       instead of ones that match at least one.

       Limit the commits output to ones with log message that do not match
       the pattern specified with --grep=<pattern>.

   -i, --regexp-ignore-case
       Match the regular expression limiting patterns without regard to
       letter case.

       Consider the limiting patterns to be basic regular expressions;
       this is the default.

   -E, --extended-regexp
       Consider the limiting patterns to be extended regular expressions
       instead of the default basic regular expressions.

   -F, --fixed-strings
       Consider the limiting patterns to be fixed strings (don't interpret
       pattern as a regular expression).

       Consider the limiting patterns to be Perl-compatible regular
       expressions. Requires libpcre to be compiled in.

       Stop when a given path disappears from the tree.

       Print only merge commits. This is exactly the same as

       Do not print commits with more than one parent. This is exactly the
       same as --max-parents=1.

   --min-parents=<number>, --max-parents=<number>, --no-min-parents,
       Show only commits which have at least (or at most) that many parent
       commits. In particular, --max-parents=1 is the same as --no-merges,
       --min-parents=2 is the same as --merges.  --max-parents=0 gives all
       root commits and --min-parents=3 all octopus merges.

       --no-min-parents and --no-max-parents reset these limits (to no
       limit) again. Equivalent forms are --min-parents=0 (any commit has
       0 or more parents) and --max-parents=-1 (negative numbers denote no
       upper limit).

       Follow only the first parent commit upon seeing a merge commit.
       This option can give a better overview when viewing the evolution
       of a particular topic branch, because merges into a topic branch
       tend to be only about adjusting to updated upstream from time to
       time, and this option allows you to ignore the individual commits
       brought in to your history by such a merge. Cannot be combined with

       Reverses the meaning of the ^ prefix (or lack thereof) for all
       following revision specifiers, up to the next --not.

       Pretend as if all the refs in refs/ are listed on the command line
       as <commit>.

       Pretend as if all the refs in refs/heads are listed on the command
       line as <commit>. If <pattern> is given, limit branches to ones
       matching given shell glob. If pattern lacks ?, *, or [, /* at the
       end is implied.

       Pretend as if all the refs in refs/tags are listed on the command
       line as <commit>. If <pattern> is given, limit tags to ones
       matching given shell glob. If pattern lacks ?, *, or [, /* at the
       end is implied.

       Pretend as if all the refs in refs/remotes are listed on the
       command line as <commit>. If <pattern> is given, limit
       remote-tracking branches to ones matching given shell glob. If
       pattern lacks ?, *, or [, /* at the end is implied.

       Pretend as if all the refs matching shell glob <glob-pattern> are
       listed on the command line as <commit>. Leading refs/, is
       automatically prepended if missing. If pattern lacks ?, *, or [, /*
       at the end is implied.

       Do not include refs matching <glob-pattern> that the next --all,
       --branches, --tags, --remotes, or --glob would otherwise consider.
       Repetitions of this option accumulate exclusion patterns up to the
       next --all, --branches, --tags, --remotes, or --glob option (other
       options or arguments do not clear accumulated patterns).

       The patterns given should not begin with refs/heads, refs/tags, or
       refs/remotes when applied to --branches, --tags, or --remotes,
       respectively, and they must begin with refs/ when applied to --glob
       or --all. If a trailing /* is intended, it must be given

       Pretend as if all objects mentioned by reflogs are listed on the
       command line as <commit>.

       Upon seeing an invalid object name in the input, pretend as if the
       bad input was not given.

       Pretend as if the bad bisection ref refs/bisect/bad was listed and
       as if it was followed by --not and the good bisection refs
       refs/bisect/good-* on the command line. Cannot be combined with

       In addition to the <commit> listed on the command line, read them
       from the standard input. If a -- separator is seen, stop reading
       commits and start reading paths to limit the result.

       Like --cherry-pick (see below) but mark equivalent commits with =
       rather than omitting them, and inequivalent ones with +.

       Omit any commit that introduces the same change as another commit
       on the "other side" when the set of commits are limited with
       symmetric difference.

       For example, if you have two branches, A and B, a usual way to list
       all commits on only one side of them is with --left-right (see the
       example below in the description of the --left-right option).
       However, it shows the commits that were cherry-picked from the
       other branch (for example, "3rd on b" may be cherry-picked from
       branch A). With this option, such pairs of commits are excluded
       from the output.

   --left-only, --right-only
       List only commits on the respective side of a symmetric difference,
       i.e. only those which would be marked < resp.  > by --left-right.

       For example, --cherry-pick --right-only A...B omits those commits
       from B which are in A or are patch-equivalent to a commit in A. In
       other words, this lists the + commits from git cherry A B. More
       precisely, --cherry-pick --right-only --no-merges gives the exact

       A synonym for --right-only --cherry-mark --no-merges; useful to
       limit the output to the commits on our side and mark those that
       have been applied to the other side of a forked history with git
       log --cherry upstream...mybranch, similar to git cherry upstream

   -g, --walk-reflogs
       Instead of walking the commit ancestry chain, walk reflog entries
       from the most recent one to older ones. When this option is used
       you cannot specify commits to exclude (that is, ^commit,
       commit1..commit2, and commit1...commit2 notations cannot be used).

       With --pretty format other than oneline (for obvious reasons), this
       causes the output to have two extra lines of information taken from
       the reflog. The reflog designator in the output may be shown as
       ref@{Nth} (where Nth is the reverse-chronological index in the
       reflog) or as ref@{timestamp} (with the timestamp for that entry),
       depending on a few rules:

        1. If the starting point is specified as ref@{Nth}, show the index

        2. If the starting point was specified as ref@{now}, show the
           timestamp format.

        3. If neither was used, but --date was given on the command line,
           show the timestamp in the format requested by --date.

        4. Otherwise, show the index format.

       Under --pretty=oneline, the commit message is prefixed with this
       information on the same line. This option cannot be combined with
       --reverse. See also git-reflog(1).

       After a failed merge, show refs that touch files having a conflict
       and don't exist on all heads to merge.

       Output excluded boundary commits. Boundary commits are prefixed
       with -.

   History Simplification
   Sometimes you are only interested in parts of the history, for example
   the commits modifying a particular <path>. But there are two parts of
   History Simplification, one part is selecting the commits and the other
   is how to do it, as there are various strategies to simplify the

   The following options select the commits to be shown:

       Commits modifying the given <paths> are selected.

       Commits that are referred by some branch or tag are selected.

   Note that extra commits can be shown to give a meaningful history.

   The following options affect the way the simplification is performed:

   Default mode
       Simplifies the history to the simplest history explaining the final
       state of the tree. Simplest because it prunes some side branches if
       the end result is the same (i.e. merging branches with the same

       Same as the default mode, but does not prune some history.

       Only the selected commits are shown, plus some to have a meaningful

       All commits in the simplified history are shown.

       Additional option to --full-history to remove some needless merges
       from the resulting history, as there are no selected commits
       contributing to this merge.

       When given a range of commits to display (e.g.  commit1..commit2 or
       commit2 ^commit1), only display commits that exist directly on the
       ancestry chain between the commit1 and commit2, i.e. commits that
       are both descendants of commit1, and ancestors of commit2.

   A more detailed explanation follows.

   Suppose you specified foo as the <paths>. We shall call commits that
   modify foo !TREESAME, and the rest TREESAME. (In a diff filtered for
   foo, they look different and equal, respectively.)

   In the following, we will always refer to the same example history to
   illustrate the differences between simplification settings. We assume
   that you are filtering for a file foo in this commit graph:

                /     /   /   /   /   /
               I     B   C   D   E   Y
                \   /   /   /   /   /
                 `-------------'   X

   The horizontal line of history A---Q is taken to be the first parent of
   each merge. The commits are:

   *   I is the initial commit, in which foo exists with contents "asdf",
       and a file quux exists with contents "quux". Initial commits are
       compared to an empty tree, so I is !TREESAME.

   *   In A, foo contains just "foo".

   *   B contains the same change as A. Its merge M is trivial and hence
       TREESAME to all parents.

   *   C does not change foo, but its merge N changes it to "foobar", so
       it is not TREESAME to any parent.

   *   D sets foo to "baz". Its merge O combines the strings from N and D
       to "foobarbaz"; i.e., it is not TREESAME to any parent.

   *   E changes quux to "xyzzy", and its merge P combines the strings to
       "quux xyzzy".  P is TREESAME to O, but not to E.

   *   X is an independent root commit that added a new file side, and Y
       modified it.  Y is TREESAME to X. Its merge Q added side to P, and
       Q is TREESAME to P, but not to Y.

   rev-list walks backwards through history, including or excluding
   commits based on whether --full-history and/or parent rewriting (via
   --parents or --children) are used. The following settings are

   Default mode
       Commits are included if they are not TREESAME to any parent (though
       this can be changed, see --sparse below). If the commit was a
       merge, and it was TREESAME to one parent, follow only that parent.
       (Even if there are several TREESAME parents, follow only one of
       them.) Otherwise, follow all parents.

       This results in:

                    /     /   /

       Note how the rule to only follow the TREESAME parent, if one is
       available, removed B from consideration entirely.  C was considered
       via N, but is TREESAME. Root commits are compared to an empty tree,
       so I is !TREESAME.

       Parent/child relations are only visible with --parents, but that
       does not affect the commits selected in default mode, so we have
       shown the parent lines.

   --full-history without parent rewriting
       This mode differs from the default in one point: always follow all
       parents of a merge, even if it is TREESAME to one of them. Even if
       more than one side of the merge has commits that are included, this
       does not imply that the merge itself is! In the example, we get

                   I  A  B  N  D  O  P  Q

       M was excluded because it is TREESAME to both parents.  E, C and B
       were all walked, but only B was !TREESAME, so the others do not

       Note that without parent rewriting, it is not really possible to
       talk about the parent/child relationships between the commits, so
       we show them disconnected.

   --full-history with parent rewriting
       Ordinary commits are only included if they are !TREESAME (though
       this can be changed, see --sparse below).

       Merges are always included. However, their parent list is
       rewritten: Along each parent, prune away commits that are not
       included themselves. This results in

                    /     /   /   /   /
                   I     B   /   D   /
                    \   /   /   /   /

       Compare to --full-history without rewriting above. Note that E was
       pruned away because it is TREESAME, but the parent list of P was
       rewritten to contain E's parent I. The same happened for C and N,
       and X, Y and Q.

   In addition to the above settings, you can change whether TREESAME
   affects inclusion:

       Commits that are walked are included if they are not TREESAME to
       any parent.

       All commits that are walked are included.

       Note that without --full-history, this still simplifies merges: if
       one of the parents is TREESAME, we follow only that one, so the
       other sides of the merge are never walked.

       First, build a history graph in the same way that --full-history
       with parent rewriting does (see above).

       Then simplify each commit C to its replacement C' in the final
       history according to the following rules:

       *   Set C' to C.

       *   Replace each parent P of C' with its simplification P'. In the
           process, drop parents that are ancestors of other parents or
           that are root commits TREESAME to an empty tree, and remove
           duplicates, but take care to never drop all parents that we are
           TREESAME to.

       *   If after this parent rewriting, C' is a root or merge commit
           (has zero or >1 parents), a boundary commit, or !TREESAME, it
           remains. Otherwise, it is replaced with its only parent.

       The effect of this is best shown by way of comparing to
       --full-history with parent rewriting. The example turns into:

                    /     /       /
                   I     B       D
                    \   /       /

       Note the major differences in N, P, and Q over --full-history:

       *   N's parent list had I removed, because it is an ancestor of the
           other parent M. Still, N remained because it is !TREESAME.

       *   P's parent list similarly had I removed.  P was then removed
           completely, because it had one parent and is TREESAME.

       *   Q's parent list had Y simplified to X.  X was then removed,
           because it was a TREESAME root.  Q was then removed completely,
           because it had one parent and is TREESAME.

   Finally, there is a fifth simplification mode available:

       Limit the displayed commits to those directly on the ancestry chain
       between the "from" and "to" commits in the given commit range. I.e.
       only display commits that are ancestor of the "to" commit and
       descendants of the "from" commit.

       As an example use case, consider the following commit history:

                      /     \       \
                    /                     \

       A regular D..M computes the set of commits that are ancestors of M,
       but excludes the ones that are ancestors of D. This is useful to
       see what happened to the history leading to M since D, in the sense
       that "what does M have that did not exist in D". The result in this
       example would be all the commits, except A and B (and D itself, of

       When we want to find out what commits in M are contaminated with
       the bug introduced by D and need fixing, however, we might want to
       view only the subset of D..M that are actually descendants of D,
       i.e. excluding C and K. This is exactly what the --ancestry-path
       option does. Applied to the D..M range, it results in:

                            \       \

   The --simplify-by-decoration option allows you to view only the big
   picture of the topology of the history, by omitting commits that are
   not referenced by tags. Commits are marked as !TREESAME (in other
   words, kept after history simplification rules described above) if (1)
   they are referenced by tags, or (2) they change the contents of the
   paths given on the command line. All other commits are marked as
   TREESAME (subject to be simplified away).

   Commit Ordering
   By default, the commits are shown in reverse chronological order.

       Show no parents before all of its children are shown, but otherwise
       show commits in the commit timestamp order.

       Show no parents before all of its children are shown, but otherwise
       show commits in the author timestamp order.

       Show no parents before all of its children are shown, and avoid
       showing commits on multiple lines of history intermixed.

       For example, in a commit history like this:

                   \              \

       where the numbers denote the order of commit timestamps, git
       rev-list and friends with --date-order show the commits in the
       timestamp order: 8 7 6 5 4 3 2 1.

       With --topo-order, they would show 8 6 5 3 7 4 2 1 (or 8 7 4 2 6 5
       3 1); some older commits are shown before newer ones in order to
       avoid showing the commits from two parallel development track mixed

       Output the commits chosen to be shown (see Commit Limiting section
       above) in reverse order. Cannot be combined with --walk-reflogs.

   Object Traversal
   These options are mostly targeted for packing of Git repositories.

       Only show the given commits, but do not traverse their ancestors.
       This has no effect if a range is specified. If the argument
       unsorted is given, the commits are shown in the order they were
       given on the command line. Otherwise (if sorted or no argument was
       given), the commits are shown in reverse chronological order by
       commit time. Cannot be combined with --graph.

       Overrides a previous --no-walk.

   Commit Formatting
   --pretty[=<format>], --format=<format>
       Pretty-print the contents of the commit logs in a given format,
       where <format> can be one of oneline, short, medium, full, fuller,
       email, raw, format:<string> and tformat:<string>. When <format> is
       none of the above, and has %placeholder in it, it acts as if
       --pretty=tformat:<format> were given.

       See the "PRETTY FORMATS" section for some additional details for
       each format. When =<format> part is omitted, it defaults to medium.

       Note: you can specify the default pretty format in the repository
       configuration (see git-config(1)).

       Instead of showing the full 40-byte hexadecimal commit object name,
       show only a partial prefix. Non default number of digits can be
       specified with "--abbrev=<n>" (which also modifies diff output, if
       it is displayed).

       This should make "--pretty=oneline" a whole lot more readable for
       people using 80-column terminals.

       Show the full 40-byte hexadecimal commit object name. This negates
       --abbrev-commit and those options which imply it such as
       "--oneline". It also overrides the log.abbrevCommit variable.

       This is a shorthand for "--pretty=oneline --abbrev-commit" used

       The commit objects record the encoding used for the log message in
       their encoding header; this option can be used to tell the command
       to re-code the commit log message in the encoding preferred by the
       user. For non plumbing commands this defaults to UTF-8. Note that
       if an object claims to be encoded in X and we are outputting in X,
       we will output the object verbatim; this means that invalid
       sequences in the original commit may be copied to the output.

   --expand-tabs=<n>, --expand-tabs, --no-expand-tabs
       Perform a tab expansion (replace each tab with enough spaces to
       fill to the next display column that is multiple of <n>) in the log
       message before showing it in the output.  --expand-tabs is a
       short-hand for --expand-tabs=8, and --no-expand-tabs is a
       short-hand for --expand-tabs=0, which disables tab expansion.

       By default, tabs are expanded in pretty formats that indent the log
       message by 4 spaces (i.e.  medium, which is the default, full, and

       Show the notes (see git-notes(1)) that annotate the commit, when
       showing the commit log message. This is the default for git log,
       git show and git whatchanged commands when there is no --pretty,
       --format, or --oneline option given on the command line.

       By default, the notes shown are from the notes refs listed in the
       core.notesRef and notes.displayRef variables (or corresponding
       environment overrides). See git-config(1) for more details.

       With an optional <treeish> argument, use the treeish to find the
       notes to display. The treeish can specify the full refname when it
       begins with refs/notes/; when it begins with notes/, refs/ and
       otherwise refs/notes/ is prefixed to form a full name of the ref.

       Multiple --notes options can be combined to control which notes are
       being displayed. Examples: "--notes=foo" will show only notes from
       "refs/notes/foo"; "--notes=foo --notes" will show both notes from
       "refs/notes/foo" and from the default notes ref(s).

       Do not show notes. This negates the above --notes option, by
       resetting the list of notes refs from which notes are shown.
       Options are parsed in the order given on the command line, so e.g.
       "--notes --notes=foo --no-notes --notes=bar" will only show notes
       from "refs/notes/bar".

   --show-notes[=<treeish>], --[no-]standard-notes
       These options are deprecated. Use the above --notes/--no-notes
       options instead.

       Check the validity of a signed commit object by passing the
       signature to gpg --verify and show the output.

       Synonym for --date=relative.

       Only takes effect for dates shown in human-readable format, such as
       when using --pretty. config variable sets a default value
       for the log command's --date option. By default, dates are shown in
       the original time zone (either committer's or author's). If -local
       is appended to the format (e.g., iso-local), the user's local time
       zone is used instead.

       --date=relative shows dates relative to the current time, e.g. "2
       hours ago". The -local option has no effect for --date=relative.

       --date=local is an alias for --date=default-local.

       --date=iso (or --date=iso8601) shows timestamps in a ISO 8601-like
       format. The differences to the strict ISO 8601 format are:

       *   a space instead of the T date/time delimiter

       *   a space between time and time zone

       *   no colon between hours and minutes of the time zone

       --date=iso-strict (or --date=iso8601-strict) shows timestamps in
       strict ISO 8601 format.

       --date=rfc (or --date=rfc2822) shows timestamps in RFC 2822 format,
       often found in email messages.

       --date=short shows only the date, but not the time, in YYYY-MM-DD

       --date=raw shows the date as seconds since the epoch (1970-01-01
       00:00:00 UTC), followed by a space, and then the timezone as an
       offset from UTC (a + or - with four digits; the first two are
       hours, and the second two are minutes). I.e., as if the timestamp
       were formatted with strftime("%s %z")). Note that the -local option
       does not affect the seconds-since-epoch value (which is always
       measured in UTC), but does switch the accompanying timezone value.

       --date=unix shows the date as a Unix epoch timestamp (seconds since
       1970). As with --raw, this is always in UTC and therefore -local
       has no effect.

       --date=format:...  feeds the format ...  to your system strftime.
       Use --date=format:%c to show the date in your system locale's
       preferred format. See the strftime manual for a complete list of
       format placeholders. When using -local, the correct syntax is

       --date=default is the default format, and is similar to
       --date=rfc2822, with a few exceptions:

       *   there is no comma after the day-of-week

       *   the time zone is omitted when the local time zone is used

       Print also the parents of the commit (in the form "commit
       parent..."). Also enables parent rewriting, see History
       Simplification below.

       Print also the children of the commit (in the form "commit
       child..."). Also enables parent rewriting, see History
       Simplification below.

       Mark which side of a symmetric difference a commit is reachable
       from. Commits from the left side are prefixed with < and those from
       the right with >. If combined with --boundary, those commits are
       prefixed with -.

       For example, if you have this topology:

                        y---b---b  branch B
                       / \ /
                      /   .
                     /   / \
                    o---x---a---a  branch A

       you would get an output like this:

                   $ git rev-list --left-right --boundary --pretty=oneline A...B

                   >bbbbbbb... 3rd on b
                   >bbbbbbb... 2nd on b
                   <aaaaaaa... 3rd on a
                   <aaaaaaa... 2nd on a
                   -yyyyyyy... 1st on b
                   -xxxxxxx... 1st on a

       Draw a text-based graphical representation of the commit history on
       the left hand side of the output. This may cause extra lines to be
       printed in between commits, in order for the graph history to be
       drawn properly. Cannot be combined with --no-walk.

       This enables parent rewriting, see History Simplification below.

       This implies the --topo-order option by default, but the
       --date-order option may also be specified.

       When --graph is not used, all history branches are flattened which
       can make it hard to see that the two consecutive commits do not
       belong to a linear branch. This option puts a barrier in between
       them in that case. If <barrier> is specified, it is the string that
       will be shown instead of the default one.

   Diff Formatting
   Listed below are options that control the formatting of diff output.
   Some of them are specific to git-rev-list(1), however other diff
   options may be given. See git-diff-files(1) for more options.

       With this option, diff output for a merge commit shows the
       differences from each of the parents to the merge result
       simultaneously instead of showing pairwise diff between a parent
       and the result one at a time. Furthermore, it lists only files
       which were modified from all parents.

       This flag implies the -c option and further compresses the patch
       output by omitting uninteresting hunks whose contents in the
       parents have only two variants and the merge result picks one of
       them without modification.

       This flag makes the merge commits show the full diff like regular
       commits; for each merge parent, a separate log entry and diff is
       generated. An exception is that only diff against the first parent
       is shown when --first-parent option is given; in that case, the
       output represents the changes the merge brought into the
       then-current branch.

       Show recursive diffs.

       Show the tree objects in the diff output. This implies -r.


   If the commit is a merge, and if the pretty-format is not oneline,
   email or raw, an additional line is inserted before the Author: line.
   This line begins with "Merge: " and the sha1s of ancestral commits are
   printed, separated by spaces. Note that the listed commits may not
   necessarily be the list of the direct parent commits if you have
   limited your view of history: for example, if you are only interested
   in changes related to a certain directory or file.

   There are several built-in formats, and you can define additional
   formats by setting a pretty.<name> config option to either another
   format name, or a format: string, as described below (see git-
   config(1)). Here are the details of the built-in formats:

   *   oneline

           <sha1> <title line>

       This is designed to be as compact as possible.

   *   short

           commit <sha1>
           Author: <author>

           <title line>

   *   medium

           commit <sha1>
           Author: <author>
           Date:   <author date>

           <title line>

           <full commit message>

   *   full

           commit <sha1>
           Author: <author>
           Commit: <committer>

           <title line>

           <full commit message>

   *   fuller

           commit <sha1>
           Author:     <author>
           AuthorDate: <author date>
           Commit:     <committer>
           CommitDate: <committer date>

           <title line>

           <full commit message>

   *   email

           From <sha1> <date>
           From: <author>
           Date: <author date>
           Subject: [PATCH] <title line>

           <full commit message>

   *   raw

       The raw format shows the entire commit exactly as stored in the
       commit object. Notably, the SHA-1s are displayed in full,
       regardless of whether --abbrev or --no-abbrev are used, and parents
       information show the true parent commits, without taking grafts or
       history simplification into account. Note that this format affects
       the way commits are displayed, but not the way the diff is shown
       e.g. with git log --raw. To get full object names in a raw diff
       format, use --no-abbrev.

   *   format:<string>

       The format:<string> format allows you to specify which information
       you want to show. It works a little bit like printf format, with
       the notable exception that you get a newline with %n instead of \n.

       E.g, format:"The author of %h was %an, %ar%nThe title was >>%s<<%n"
       would show something like this:

           The author of fe6e0ee was Junio C Hamano, 23 hours ago
           The title was >>t4119: test autocomputing -p<n> for traditional diff input.<<

       The placeholders are:

       *   %H: commit hash

       *   %h: abbreviated commit hash

       *   %T: tree hash

       *   %t: abbreviated tree hash

       *   %P: parent hashes

       *   %p: abbreviated parent hashes

       *   %an: author name

       *   %aN: author name (respecting .mailmap, see git-shortlog(1) or

       *   %ae: author email

       *   %aE: author email (respecting .mailmap, see git-shortlog(1) or

       *   %ad: author date (format respects --date= option)

       *   %aD: author date, RFC2822 style

       *   %ar: author date, relative

       *   %at: author date, UNIX timestamp

       *   %ai: author date, ISO 8601-like format

       *   %aI: author date, strict ISO 8601 format

       *   %cn: committer name

       *   %cN: committer name (respecting .mailmap, see git-shortlog(1)
           or git-blame(1))

       *   %ce: committer email

       *   %cE: committer email (respecting .mailmap, see git-shortlog(1)
           or git-blame(1))

       *   %cd: committer date (format respects --date= option)

       *   %cD: committer date, RFC2822 style

       *   %cr: committer date, relative

       *   %ct: committer date, UNIX timestamp

       *   %ci: committer date, ISO 8601-like format

       *   %cI: committer date, strict ISO 8601 format

       *   %d: ref names, like the --decorate option of git-log(1)

       *   %D: ref names without the " (", ")" wrapping.

       *   %e: encoding

       *   %s: subject

       *   %f: sanitized subject line, suitable for a filename

       *   %b: body

       *   %B: raw body (unwrapped subject and body)

       *   %N: commit notes

       *   %GG: raw verification message from GPG for a signed commit

       *   %G?: show "G" for a good (valid) signature, "B" for a bad
           signature, "U" for a good signature with unknown validity and
           "N" for no signature

       *   %GS: show the name of the signer for a signed commit

       *   %GK: show the key used to sign a signed commit

       *   %gD: reflog selector, e.g., refs/stash@{1} or refs/stash@{2
           minutes ago}; the format follows the rules described for the -g
           option. The portion before the @ is the refname as given on the
           command line (so git log -g refs/heads/master would yield

       *   %gd: shortened reflog selector; same as %gD, but the refname
           portion is shortened for human readability (so
           refs/heads/master becomes just master).

       *   %gn: reflog identity name

       *   %gN: reflog identity name (respecting .mailmap, see git-
           shortlog(1) or git-blame(1))

       *   %ge: reflog identity email

       *   %gE: reflog identity email (respecting .mailmap, see git-
           shortlog(1) or git-blame(1))

       *   %gs: reflog subject

       *   %Cred: switch color to red

       *   %Cgreen: switch color to green

       *   %Cblue: switch color to blue

       *   %Creset: reset color

       *   %C(...): color specification, as described under Values in the
           "CONFIGURATION FILE" section of git-config(1); adding auto, at
           the beginning will emit color only when colors are enabled for
           log output (by color.diff, color.ui, or --color, and respecting
           the auto settings of the former if we are going to a terminal).
           auto alone (i.e.  %C(auto)) will turn on auto coloring on the
           next placeholders until the color is switched again.

       *   %m: left (<), right (>) or boundary (-) mark

       *   %n: newline

       *   %%: a raw %

       *   %x00: print a byte from a hex code

       *   %w([<w>[,<i1>[,<i2>]]]): switch line wrapping, like the -w
           option of git-shortlog(1).

       *   %<(<N>[,trunc|ltrunc|mtrunc]): make the next placeholder take
           at least N columns, padding spaces on the right if necessary.
           Optionally truncate at the beginning (ltrunc), the middle
           (mtrunc) or the end (trunc) if the output is longer than N
           columns. Note that truncating only works correctly with N >= 2.

       *   %<|(<N>): make the next placeholder take at least until Nth
           columns, padding spaces on the right if necessary

       *   %>(<N>), %>|(<N>): similar to %<(<N>), %<|(<N>) respectively,
           but padding spaces on the left

       *   %>>(<N>), %>>|(<N>): similar to %>(<N>), %>|(<N>) respectively,
           except that if the next placeholder takes more spaces than
           given and there are spaces on its left, use those spaces

       *   %><(<N>), %><|(<N>): similar to % <(<N>), %<|(<N>)
           respectively, but padding both sides (i.e. the text is

       Some placeholders may depend on other options given to the revision
       traversal engine. For example, the %g* reflog options will insert
       an empty string unless we are traversing reflog entries (e.g., by
       git log -g). The %d and %D placeholders will use the "short"
       decoration format if --decorate was not already provided on the
       command line.

   If you add a + (plus sign) after % of a placeholder, a line-feed is
   inserted immediately before the expansion if and only if the
   placeholder expands to a non-empty string.

   If you add a - (minus sign) after % of a placeholder, line-feeds that
   immediately precede the expansion are deleted if and only if the
   placeholder expands to an empty string.

   If you add a ` ` (space) after % of a placeholder, a space is inserted
   immediately before the expansion if and only if the placeholder expands
   to a non-empty string.

   *   tformat:

       The tformat: format works exactly like format:, except that it
       provides "terminator" semantics instead of "separator" semantics.
       In other words, each commit has the message terminator character
       (usually a newline) appended, rather than a separator placed
       between entries. This means that the final entry of a single-line
       format will be properly terminated with a new line, just as the
       "oneline" format does. For example:

           $ git log -2 --pretty=format:%h 4da45bef \
             | perl -pe '$_ .= " -- NO NEWLINE\n" unless /\n/'
           7134973 -- NO NEWLINE

           $ git log -2 --pretty=tformat:%h 4da45bef \
             | perl -pe '$_ .= " -- NO NEWLINE\n" unless /\n/'

       In addition, any unrecognized string that has a % in it is
       interpreted as if it has tformat: in front of it. For example,
       these two are equivalent:

           $ git log -2 --pretty=tformat:%h 4da45bef
           $ git log -2 --pretty=%h 4da45bef


   -p, -u, --patch
       Generate patch (see section on generating patches).

   -s, --no-patch
       Suppress diff output. Useful for commands like git show that show
       the patch by default, or to cancel the effect of --patch.

   -U<n>, --unified=<n>
       Generate diffs with <n> lines of context instead of the usual
       three. Implies -p.

       For each commit, show a summary of changes using the raw diff
       format. See the "RAW OUTPUT FORMAT" section of git-diff(1). This is
       different from showing the log itself in raw format, which you can
       achieve with --format=raw.

       Synonym for -p --raw.

   --compaction-heuristic, --no-compaction-heuristic
       These are to help debugging and tuning an experimental heuristic
       (which is off by default) that shifts the hunk boundary in an
       attempt to make the resulting patch easier to read.

       Spend extra time to make sure the smallest possible diff is

       Generate a diff using the "patience diff" algorithm.

       Generate a diff using the "histogram diff" algorithm.

       Choose a diff algorithm. The variants are as follows:

       default, myers
           The basic greedy diff algorithm. Currently, this is the

           Spend extra time to make sure the smallest possible diff is

           Use "patience diff" algorithm when generating patches.

           This algorithm extends the patience algorithm to "support
           low-occurrence common elements".

       For instance, if you configured diff.algorithm variable to a
       non-default value and want to use the default one, then you have to
       use --diff-algorithm=default option.

       Generate a diffstat. By default, as much space as necessary will be
       used for the filename part, and the rest for the graph part.
       Maximum width defaults to terminal width, or 80 columns if not
       connected to a terminal, and can be overridden by <width>. The
       width of the filename part can be limited by giving another width
       <name-width> after a comma. The width of the graph part can be
       limited by using --stat-graph-width=<width> (affects all commands
       generating a stat graph) or by setting diff.statGraphWidth=<width>
       (does not affect git format-patch). By giving a third parameter
       <count>, you can limit the output to the first <count> lines,
       followed by ...  if there are more.

       These parameters can also be set individually with
       --stat-width=<width>, --stat-name-width=<name-width> and

       Similar to --stat, but shows number of added and deleted lines in
       decimal notation and pathname without abbreviation, to make it more
       machine friendly. For binary files, outputs two - instead of saying
       0 0.

       Output only the last line of the --stat format containing total
       number of modified files, as well as number of added and deleted

       Output the distribution of relative amount of changes for each
       sub-directory. The behavior of --dirstat can be customized by
       passing it a comma separated list of parameters. The defaults are
       controlled by the diff.dirstat configuration variable (see git-
       config(1)). The following parameters are available:

           Compute the dirstat numbers by counting the lines that have
           been removed from the source, or added to the destination. This
           ignores the amount of pure code movements within a file. In
           other words, rearranging lines in a file is not counted as much
           as other changes. This is the default behavior when no
           parameter is given.

           Compute the dirstat numbers by doing the regular line-based
           diff analysis, and summing the removed/added line counts. (For
           binary files, count 64-byte chunks instead, since binary files
           have no natural concept of lines). This is a more expensive
           --dirstat behavior than the changes behavior, but it does count
           rearranged lines within a file as much as other changes. The
           resulting output is consistent with what you get from the other
           --*stat options.

           Compute the dirstat numbers by counting the number of files
           changed. Each changed file counts equally in the dirstat
           analysis. This is the computationally cheapest --dirstat
           behavior, since it does not have to look at the file contents
           at all.

           Count changes in a child directory for the parent directory as
           well. Note that when using cumulative, the sum of the
           percentages reported may exceed 100%. The default
           (non-cumulative) behavior can be specified with the
           noncumulative parameter.

           An integer parameter specifies a cut-off percent (3% by
           default). Directories contributing less than this percentage of
           the changes are not shown in the output.

       Example: The following will count changed files, while ignoring
       directories with less than 10% of the total amount of changed
       files, and accumulating child directory counts in the parent
       directories: --dirstat=files,10,cumulative.

       Output a condensed summary of extended header information such as
       creations, renames and mode changes.

       Synonym for -p --stat.

       Separate the commits with NULs instead of with new newlines.

       Also, when --raw or --numstat has been given, do not munge
       pathnames and use NULs as output field terminators.

       Without this option, each pathname output will have TAB, LF, double
       quotes, and backslash characters replaced with \t, \n, \", and \\,
       respectively, and the pathname will be enclosed in double quotes if
       any of those replacements occurred.

       Show only names of changed files.

       Show only names and status of changed files. See the description of
       the --diff-filter option on what the status letters mean.

       Specify how differences in submodules are shown. When --submodule
       or --submodule=log is given, the log format is used. This format
       lists the commits in the range like git-submodule(1) summary does.
       Omitting the --submodule option or specifying --submodule=short,
       uses the short format. This format just shows the names of the
       commits at the beginning and end of the range. Can be tweaked via
       the diff.submodule configuration variable.

       Show colored diff.  --color (i.e. without =<when>) is the same as
       --color=always.  <when> can be one of always, never, or auto.

       Turn off colored diff. It is the same as --color=never.

       Show a word diff, using the <mode> to delimit changed words. By
       default, words are delimited by whitespace; see --word-diff-regex
       below. The <mode> defaults to plain, and must be one of:

           Highlight changed words using only colors. Implies --color.

           Show words as [-removed-] and {+added+}. Makes no attempts to
           escape the delimiters if they appear in the input, so the
           output may be ambiguous.

           Use a special line-based format intended for script
           consumption. Added/removed/unchanged runs are printed in the
           usual unified diff format, starting with a +/-/` ` character at
           the beginning of the line and extending to the end of the line.
           Newlines in the input are represented by a tilde ~ on a line of
           its own.

           Disable word diff again.

       Note that despite the name of the first mode, color is used to
       highlight the changed parts in all modes if enabled.

       Use <regex> to decide what a word is, instead of considering runs
       of non-whitespace to be a word. Also implies --word-diff unless it
       was already enabled.

       Every non-overlapping match of the <regex> is considered a word.
       Anything between these matches is considered whitespace and
       ignored(!) for the purposes of finding differences. You may want to
       append |[^[:space:]] to your regular expression to make sure that
       it matches all non-whitespace characters. A match that contains a
       newline is silently truncated(!) at the newline.

       For example, --word-diff-regex=.  will treat each character as a
       word and, correspondingly, show differences character by character.

       The regex can also be set via a diff driver or configuration
       option, see gitattributes(5) or git-config(1). Giving it explicitly
       overrides any diff driver or configuration setting. Diff drivers
       override configuration settings.

       Equivalent to --word-diff=color plus (if a regex was specified)

       Turn off rename detection, even when the configuration file gives
       the default to do so.

       Warn if changes introduce conflict markers or whitespace errors.
       What are considered whitespace errors is controlled by
       core.whitespace configuration. By default, trailing whitespaces
       (including lines that solely consist of whitespaces) and a space
       character that is immediately followed by a tab character inside
       the initial indent of the line are considered whitespace errors.
       Exits with non-zero status if problems are found. Not compatible
       with --exit-code.

       Highlight whitespace errors on lines specified by <kind> in the
       color specified by color.diff.whitespace. <kind> is a comma
       separated list of old, new, context. When this option is not given,
       only whitespace errors in new lines are highlighted. E.g.
       --ws-error-highlight=new,old highlights whitespace errors on both
       deleted and added lines.  all can be used as a short-hand for

       Instead of the first handful of characters, show the full pre- and
       post-image blob object names on the "index" line when generating
       patch format output.

       In addition to --full-index, output a binary diff that can be
       applied with git-apply.

       Instead of showing the full 40-byte hexadecimal object name in
       diff-raw format output and diff-tree header lines, show only a
       partial prefix. This is independent of the --full-index option
       above, which controls the diff-patch output format. Non default
       number of digits can be specified with --abbrev=<n>.

   -B[<n>][/<m>], --break-rewrites[=[<n>][/<m>]]
       Break complete rewrite changes into pairs of delete and create.
       This serves two purposes:

       It affects the way a change that amounts to a total rewrite of a
       file not as a series of deletion and insertion mixed together with
       a very few lines that happen to match textually as the context, but
       as a single deletion of everything old followed by a single
       insertion of everything new, and the number m controls this aspect
       of the -B option (defaults to 60%).  -B/70% specifies that less
       than 30% of the original should remain in the result for Git to
       consider it a total rewrite (i.e. otherwise the resulting patch
       will be a series of deletion and insertion mixed together with
       context lines).

       When used with -M, a totally-rewritten file is also considered as
       the source of a rename (usually -M only considers a file that
       disappeared as the source of a rename), and the number n controls
       this aspect of the -B option (defaults to 50%).  -B20% specifies
       that a change with addition and deletion compared to 20% or more of
       the file's size are eligible for being picked up as a possible
       source of a rename to another file.

   -M[<n>], --find-renames[=<n>]
       If generating diffs, detect and report renames for each commit. For
       following files across renames while traversing history, see
       --follow. If n is specified, it is a threshold on the similarity
       index (i.e. amount of addition/deletions compared to the file's
       size). For example, -M90% means Git should consider a delete/add
       pair to be a rename if more than 90% of the file hasn't changed.
       Without a % sign, the number is to be read as a fraction, with a
       decimal point before it. I.e., -M5 becomes 0.5, and is thus the
       same as -M50%. Similarly, -M05 is the same as -M5%. To limit
       detection to exact renames, use -M100%. The default similarity
       index is 50%.

   -C[<n>], --find-copies[=<n>]
       Detect copies as well as renames. See also --find-copies-harder. If
       n is specified, it has the same meaning as for -M<n>.

       For performance reasons, by default, -C option finds copies only if
       the original file of the copy was modified in the same changeset.
       This flag makes the command inspect unmodified files as candidates
       for the source of copy. This is a very expensive operation for
       large projects, so use it with caution. Giving more than one -C
       option has the same effect.

   -D, --irreversible-delete
       Omit the preimage for deletes, i.e. print only the header but not
       the diff between the preimage and /dev/null. The resulting patch is
       not meant to be applied with patch or git apply; this is solely for
       people who want to just concentrate on reviewing the text after the
       change. In addition, the output obviously lack enough information
       to apply such a patch in reverse, even manually, hence the name of
       the option.

       When used together with -B, omit also the preimage in the deletion
       part of a delete/create pair.

       The -M and -C options require O(n^2) processing time where n is the
       number of potential rename/copy targets. This option prevents
       rename/copy detection from running if the number of rename/copy
       targets exceeds the specified number.

       Select only files that are Added (A), Copied (C), Deleted (D),
       Modified (M), Renamed (R), have their type (i.e. regular file,
       symlink, submodule, ...) changed (T), are Unmerged (U), are Unknown
       (X), or have had their pairing Broken (B). Any combination of the
       filter characters (including none) can be used. When *
       (All-or-none) is added to the combination, all paths are selected
       if there is any file that matches other criteria in the comparison;
       if there is no file that matches other criteria, nothing is

       Also, these upper-case letters can be downcased to exclude. E.g.
       --diff-filter=ad excludes added and deleted paths.

       Look for differences that change the number of occurrences of the
       specified string (i.e. addition/deletion) in a file. Intended for
       the scripter's use.

       It is useful when you're looking for an exact block of code (like a
       struct), and want to know the history of that block since it first
       came into being: use the feature iteratively to feed the
       interesting block in the preimage back into -S, and keep going
       until you get the very first version of the block.

       Look for differences whose patch text contains added/removed lines
       that match <regex>.

       To illustrate the difference between -S<regex> --pickaxe-regex and
       -G<regex>, consider a commit with the following diff in the same

           +    return !regexec(regexp, two->ptr, 1, &regmatch, 0);
           -    hit = !regexec(regexp, mf2.ptr, 1, &regmatch, 0);

       While git log -G"regexec\(regexp" will show this commit, git log
       -S"regexec\(regexp" --pickaxe-regex will not (because the number of
       occurrences of that string did not change).

       See the pickaxe entry in gitdiffcore(7) for more information.

       When -S or -G finds a change, show all the changes in that
       changeset, not just the files that contain the change in <string>.

       Treat the <string> given to -S as an extended POSIX regular
       expression to match.

       Output the patch in the order specified in the <orderfile>, which
       has one shell glob pattern per line. This overrides the
       diff.orderFile configuration variable (see git-config(1)). To
       cancel diff.orderFile, use -O/dev/null.

       Swap two inputs; that is, show differences from index or on-disk
       file to tree contents.

       When run from a subdirectory of the project, it can be told to
       exclude changes outside the directory and show pathnames relative
       to it with this option. When you are not in a subdirectory (e.g. in
       a bare repository), you can name which subdirectory to make the
       output relative to by giving a <path> as an argument.

   -a, --text
       Treat all files as text.

       Ignore changes in whitespace at EOL.

   -b, --ignore-space-change
       Ignore changes in amount of whitespace. This ignores whitespace at
       line end, and considers all other sequences of one or more
       whitespace characters to be equivalent.

   -w, --ignore-all-space
       Ignore whitespace when comparing lines. This ignores differences
       even if one line has whitespace where the other line has none.

       Ignore changes whose lines are all blank.

       Show the context between diff hunks, up to the specified number of
       lines, thereby fusing hunks that are close to each other.

   -W, --function-context
       Show whole surrounding functions of changes.

       Allow an external diff helper to be executed. If you set an
       external diff driver with gitattributes(5), you need to use this
       option with git-log(1) and friends.

       Disallow external diff drivers.

   --textconv, --no-textconv
       Allow (or disallow) external text conversion filters to be run when
       comparing binary files. See gitattributes(5) for details. Because
       textconv filters are typically a one-way conversion, the resulting
       diff is suitable for human consumption, but cannot be applied. For
       this reason, textconv filters are enabled by default only for git-
       diff(1) and git-log(1), but not for git-format-patch(1) or diff
       plumbing commands.

       Ignore changes to submodules in the diff generation. <when> can be
       either "none", "untracked", "dirty" or "all", which is the default.
       Using "none" will consider the submodule modified when it either
       contains untracked or modified files or its HEAD differs from the
       commit recorded in the superproject and can be used to override any
       settings of the ignore option in git-config(1) or gitmodules(5).
       When "untracked" is used submodules are not considered dirty when
       they only contain untracked content (but they are still scanned for
       modified content). Using "dirty" ignores all changes to the work
       tree of submodules, only changes to the commits stored in the
       superproject are shown (this was the behavior until 1.7.0). Using
       "all" hides all changes to submodules.

       Show the given source prefix instead of "a/".

       Show the given destination prefix instead of "b/".

       Do not show any source or destination prefix.

   For more detailed explanation on these common options, see also


   When "git-diff-index", "git-diff-tree", or "git-diff-files" are run
   with a -p option, "git diff" without the --raw option, or "git log"
   with the "-p" option, they do not produce the output described above;
   instead they produce a patch file. You can customize the creation of
   such patches via the GIT_EXTERNAL_DIFF and the GIT_DIFF_OPTS
   environment variables.

   What the -p option produces is slightly different from the traditional
   diff format:

    1. It is preceded with a "git diff" header that looks like this:

           diff --git a/file1 b/file2

       The a/ and b/ filenames are the same unless rename/copy is
       involved. Especially, even for a creation or a deletion, /dev/null
       is not used in place of the a/ or b/ filenames.

       When rename/copy is involved, file1 and file2 show the name of the
       source file of the rename/copy and the name of the file that
       rename/copy produces, respectively.

    2. It is followed by one or more extended header lines:

           old mode <mode>
           new mode <mode>
           deleted file mode <mode>
           new file mode <mode>
           copy from <path>
           copy to <path>
           rename from <path>
           rename to <path>
           similarity index <number>
           dissimilarity index <number>
           index <hash>..<hash> <mode>

       File modes are printed as 6-digit octal numbers including the file
       type and file permission bits.

       Path names in extended headers do not include the a/ and b/

       The similarity index is the percentage of unchanged lines, and the
       dissimilarity index is the percentage of changed lines. It is a
       rounded down integer, followed by a percent sign. The similarity
       index value of 100% is thus reserved for two equal files, while
       100% dissimilarity means that no line from the old file made it
       into the new one.

       The index line includes the SHA-1 checksum before and after the
       change. The <mode> is included if the file mode does not change;
       otherwise, separate lines indicate the old and the new mode.

    3. TAB, LF, double quote and backslash characters in pathnames are
       represented as \t, \n, \" and \\, respectively. If there is need
       for such substitution then the whole pathname is put in double

    4. All the file1 files in the output refer to files before the commit,
       and all the file2 files refer to files after the commit. It is
       incorrect to apply each change to each file sequentially. For
       example, this patch will swap a and b:

           diff --git a/a b/b
           rename from a
           rename to b
           diff --git a/b b/a
           rename from b
           rename to a


   Any diff-generating command can take the -c or --cc option to produce a
   combined diff when showing a merge. This is the default format when
   showing merges with git-diff(1) or git-show(1). Note also that you can
   give the -m option to any of these commands to force generation of
   diffs with individual parents of a merge.

   A combined diff format looks like this:

       diff --combined describe.c
       index fabadb8,cc95eb0..4866510
       --- a/describe.c
       +++ b/describe.c
       @@@ -98,20 -98,12 +98,20 @@@
               return (a_date > b_date) ? -1 : (a_date == b_date) ? 0 : 1;

       - static void describe(char *arg)
        -static void describe(struct commit *cmit, int last_one)
       ++static void describe(char *arg, int last_one)
        +      unsigned char sha1[20];
        +      struct commit *cmit;
               struct commit_list *list;
               static int initialized = 0;
               struct commit_name *n;

        +      if (get_sha1(arg, sha1) < 0)
        +              usage(describe_usage);
        +      cmit = lookup_commit_reference(sha1);
        +      if (!cmit)
        +              usage(describe_usage);
               if (!initialized) {
                       initialized = 1;

    1. It is preceded with a "git diff" header, that looks like this (when
       -c option is used):

           diff --combined file

       or like this (when --cc option is used):

           diff --cc file

    2. It is followed by one or more extended header lines (this example
       shows a merge with two parents):

           index <hash>,<hash>..<hash>
           mode <mode>,<mode>..<mode>
           new file mode <mode>
           deleted file mode <mode>,<mode>

       The mode <mode>,<mode>..<mode> line appears only if at least one of
       the <mode> is different from the rest. Extended headers with
       information about detected contents movement (renames and copying
       detection) are designed to work with diff of two <tree-ish> and are
       not used by combined diff format.

    3. It is followed by two-line from-file/to-file header

           --- a/file
           +++ b/file

       Similar to two-line header for traditional unified diff format,
       /dev/null is used to signal created or deleted files.

    4. Chunk header format is modified to prevent people from accidentally
       feeding it to patch -p1. Combined diff format was created for
       review of merge commit changes, and was not meant for apply. The
       change is similar to the change in the extended index header:

           @@@ <from-file-range> <from-file-range> <to-file-range> @@@

       There are (number of parents + 1) @ characters in the chunk header
       for combined diff format.

   Unlike the traditional unified diff format, which shows two files A and
   B with a single column that has - (minus --- appears in A but removed in
   B), + (plus --- missing in A but added to B), or " " (space --- unchanged)
   prefix, this format compares two or more files file1, file2,... with
   one file X, and shows how X differs from each of fileN. One column for
   each of fileN is prepended to the output line to note how X's line is
   different from it.

   A - character in the column N means that the line appears in fileN but
   it does not appear in the result. A + character in the column N means
   that the line appears in the result, and fileN does not have that line
   (in other words, the line was added, from the point of view of that

   In the above example output, the function signature was changed from
   both files (hence two - removals from both file1 and file2, plus ++ to
   mean one line that was added does not appear in either file1 or file2).
   Also eight other lines are the same from file1 but do not appear in
   file2 (hence prefixed with +).

   When shown by git diff-tree -c, it compares the parents of a merge
   commit with the merge result (i.e. file1..fileN are the parents). When
   shown by git diff-files -c, it compares the two unresolved merge
   parents with the working tree file (i.e. file1 is stage 2 aka "our
   version", file2 is stage 3 aka "their version").


   git log --no-merges
       Show the whole commit history, but skip any merges

   git log v2.6.12.. include/scsi drivers/scsi
       Show all commits since version v2.6.12 that changed any file in the
       include/scsi or drivers/scsi subdirectories

   git log --since="2 weeks ago" -- gitk
       Show the changes during the last two weeks to the file gitk. The
       "--" is necessary to avoid confusion with the branch named gitk

   git log --name-status release..test
       Show the commits that are in the "test" branch but not yet in the
       "release" branch, along with the list of paths each commit

   git log --follow builtin/rev-list.c
       Shows the commits that changed builtin/rev-list.c, including those
       commits that occurred before the file was given its present name.

   git log --branches --not --remotes=origin
       Shows all commits that are in any of local branches but not in any
       of remote-tracking branches for origin (what you have that origin

   git log master --not --remotes=*/master
       Shows all commits that are in local master but not in any remote
       repository master branches.

   git log -p -m --first-parent
       Shows the history including change diffs, but only from the "main
       branch" perspective, skipping commits that come from merged
       branches, and showing full diffs of changes introduced by the
       merges. This makes sense only when following a strict policy of
       merging all topic branches when staying on a single integration

   git log -L '/int main/',/^}/:main.c
       Shows how the function main() in the file main.c evolved over time.

   git log -3
       Limits the number of commits to show to 3.


   Git is to some extent character encoding agnostic.

   *   The contents of the blob objects are uninterpreted sequences of
       bytes. There is no encoding translation at the core level.

   *   Path names are encoded in UTF-8 normalization form C. This applies
       to tree objects, the index file, ref names, as well as path names
       in command line arguments, environment variables and config files
       (.git/config (see git-config(1)), gitignore(5), gitattributes(5)
       and gitmodules(5)).

       Note that Git at the core level treats path names simply as
       sequences of non-NUL bytes, there are no path name encoding
       conversions (except on Mac and Windows). Therefore, using non-ASCII
       path names will mostly work even on platforms and file systems that
       use legacy extended ASCII encodings. However, repositories created
       on such systems will not work properly on UTF-8-based systems (e.g.
       Linux, Mac, Windows) and vice versa. Additionally, many Git-based
       tools simply assume path names to be UTF-8 and will fail to display
       other encodings correctly.

   *   Commit log messages are typically encoded in UTF-8, but other
       extended ASCII encodings are also supported. This includes
       ISO-8859-x, CP125x and many others, but not UTF-16/32, EBCDIC and
       CJK multi-byte encodings (GBK, Shift-JIS, Big5, EUC-x, CP9xx etc.).

   Although we encourage that the commit log messages are encoded in
   UTF-8, both the core and Git Porcelain are designed not to force UTF-8
   on projects. If all participants of a particular project find it more
   convenient to use legacy encodings, Git does not forbid it. However,
   there are a few things to keep in mind.

    1. git commit and git commit-tree issues a warning if the commit log
       message given to it does not look like a valid UTF-8 string, unless
       you explicitly say your project uses a legacy encoding. The way to
       say this is to have i18n.commitencoding in .git/config file, like

                   commitencoding = ISO-8859-1

       Commit objects created with the above setting record the value of
       i18n.commitencoding in its encoding header. This is to help other
       people who look at them later. Lack of this header implies that the
       commit log message is encoded in UTF-8.

    2. git log, git show, git blame and friends look at the encoding
       header of a commit object, and try to re-code the log message into
       UTF-8 unless otherwise specified. You can specify the desired
       output encoding with i18n.logoutputencoding in .git/config file,
       like this:

                   logoutputencoding = ISO-8859-1

       If you do not have this configuration variable, the value of
       i18n.commitencoding is used instead.

   Note that we deliberately chose not to re-code the commit log message
   when a commit is made to force UTF-8 at the commit object level,
   because re-coding to UTF-8 is not necessarily a reversible operation.


   See git-config(1) for core variables and git-diff(1) for settings
   related to diff generation.

       Default for the --format option. (See Pretty Formats above.)
       Defaults to medium.

       Encoding to use when displaying logs. (See Discussion above.)
       Defaults to the value of i18n.commitEncoding if set, and UTF-8
       Default format for human-readable dates. (Compare the --date
       option.) Defaults to "default", which means to write dates like Sat
       May 8 19:35:34 2010 -0500.

       If true, git log will act as if the --follow option was used when a
       single <path> is given. This has the same limitations as --follow,
       i.e. it cannot be used to follow multiple files and does not work
       well on non-linear history.

       If false, git log and related commands will not treat the initial
       commit as a big creation event. Any root commits in git log -p
       output would be shown without a diff attached. The default is true.

       If true, git log and related commands will act as if the
       --show-signature option was passed to them.

       See git-shortlog(1).

       Which refs, in addition to the default set by core.notesRef or
       GIT_NOTES_REF, to read notes from when showing commit messages with
       the log family of commands. See git-notes(1).

       May be an unabbreviated ref name or a glob and may be specified
       multiple times. A warning will be issued for refs that do not
       exist, but a glob that does not match any refs is silently ignored.

       This setting can be disabled by the --no-notes option, overridden
       by the GIT_NOTES_DISPLAY_REF environment variable, and overridden
       by the --notes=<ref> option.


   Part of the git(1) suite


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