Documentation / diff-options.txton commit diff: improve positioning of add/delete blocks in diffs (433860f)
   1// Please don't remove this comment as asciidoc behaves badly when
   2// the first non-empty line is ifdef/ifndef. The symptom is that
   3// without this comment the <git-diff-core> attribute conditionally
   4// defined below ends up being defined unconditionally.
   5// Last checked with asciidoc 7.0.2.
   6
   7ifndef::git-format-patch[]
   8ifndef::git-diff[]
   9ifndef::git-log[]
  10:git-diff-core: 1
  11endif::git-log[]
  12endif::git-diff[]
  13endif::git-format-patch[]
  14
  15ifdef::git-format-patch[]
  16-p::
  17--no-stat::
  18        Generate plain patches without any diffstats.
  19endif::git-format-patch[]
  20
  21ifndef::git-format-patch[]
  22-p::
  23-u::
  24--patch::
  25        Generate patch (see section on generating patches).
  26ifdef::git-diff[]
  27        This is the default.
  28endif::git-diff[]
  29
  30-s::
  31--no-patch::
  32        Suppress diff output. Useful for commands like `git show` that
  33        show the patch by default, or to cancel the effect of `--patch`.
  34endif::git-format-patch[]
  35
  36-U<n>::
  37--unified=<n>::
  38        Generate diffs with <n> lines of context instead of
  39        the usual three.
  40ifndef::git-format-patch[]
  41        Implies `-p`.
  42endif::git-format-patch[]
  43
  44ifndef::git-format-patch[]
  45--raw::
  46ifndef::git-log[]
  47        Generate the diff in raw format.
  48ifdef::git-diff-core[]
  49        This is the default.
  50endif::git-diff-core[]
  51endif::git-log[]
  52ifdef::git-log[]
  53        For each commit, show a summary of changes using the raw diff
  54        format. See the "RAW OUTPUT FORMAT" section of
  55        linkgit:git-diff[1]. This is different from showing the log
  56        itself in raw format, which you can achieve with
  57        `--format=raw`.
  58endif::git-log[]
  59endif::git-format-patch[]
  60
  61ifndef::git-format-patch[]
  62--patch-with-raw::
  63        Synonym for `-p --raw`.
  64endif::git-format-patch[]
  65
  66--indent-heuristic::
  67--no-indent-heuristic::
  68--compaction-heuristic::
  69--no-compaction-heuristic::
  70        These are to help debugging and tuning experimental heuristics
  71        (which are off by default) that shift diff hunk boundaries to
  72        make patches easier to read.
  73
  74--minimal::
  75        Spend extra time to make sure the smallest possible
  76        diff is produced.
  77
  78--patience::
  79        Generate a diff using the "patience diff" algorithm.
  80
  81--histogram::
  82        Generate a diff using the "histogram diff" algorithm.
  83
  84--diff-algorithm={patience|minimal|histogram|myers}::
  85        Choose a diff algorithm. The variants are as follows:
  86+
  87--
  88`default`, `myers`;;
  89        The basic greedy diff algorithm. Currently, this is the default.
  90`minimal`;;
  91        Spend extra time to make sure the smallest possible diff is
  92        produced.
  93`patience`;;
  94        Use "patience diff" algorithm when generating patches.
  95`histogram`;;
  96        This algorithm extends the patience algorithm to "support
  97        low-occurrence common elements".
  98--
  99+
 100For instance, if you configured diff.algorithm variable to a
 101non-default value and want to use the default one, then you
 102have to use `--diff-algorithm=default` option.
 103
 104--stat[=<width>[,<name-width>[,<count>]]]::
 105        Generate a diffstat. By default, as much space as necessary
 106        will be used for the filename part, and the rest for the graph
 107        part. Maximum width defaults to terminal width, or 80 columns
 108        if not connected to a terminal, and can be overridden by
 109        `<width>`. The width of the filename part can be limited by
 110        giving another width `<name-width>` after a comma. The width
 111        of the graph part can be limited by using
 112        `--stat-graph-width=<width>` (affects all commands generating
 113        a stat graph) or by setting `diff.statGraphWidth=<width>`
 114        (does not affect `git format-patch`).
 115        By giving a third parameter `<count>`, you can limit the
 116        output to the first `<count>` lines, followed by `...` if
 117        there are more.
 118+
 119These parameters can also be set individually with `--stat-width=<width>`,
 120`--stat-name-width=<name-width>` and `--stat-count=<count>`.
 121
 122--numstat::
 123        Similar to `--stat`, but shows number of added and
 124        deleted lines in decimal notation and pathname without
 125        abbreviation, to make it more machine friendly.  For
 126        binary files, outputs two `-` instead of saying
 127        `0 0`.
 128
 129--shortstat::
 130        Output only the last line of the `--stat` format containing total
 131        number of modified files, as well as number of added and deleted
 132        lines.
 133
 134--dirstat[=<param1,param2,...>]::
 135        Output the distribution of relative amount of changes for each
 136        sub-directory. The behavior of `--dirstat` can be customized by
 137        passing it a comma separated list of parameters.
 138        The defaults are controlled by the `diff.dirstat` configuration
 139        variable (see linkgit:git-config[1]).
 140        The following parameters are available:
 141+
 142--
 143`changes`;;
 144        Compute the dirstat numbers by counting the lines that have been
 145        removed from the source, or added to the destination. This ignores
 146        the amount of pure code movements within a file.  In other words,
 147        rearranging lines in a file is not counted as much as other changes.
 148        This is the default behavior when no parameter is given.
 149`lines`;;
 150        Compute the dirstat numbers by doing the regular line-based diff
 151        analysis, and summing the removed/added line counts. (For binary
 152        files, count 64-byte chunks instead, since binary files have no
 153        natural concept of lines). This is a more expensive `--dirstat`
 154        behavior than the `changes` behavior, but it does count rearranged
 155        lines within a file as much as other changes. The resulting output
 156        is consistent with what you get from the other `--*stat` options.
 157`files`;;
 158        Compute the dirstat numbers by counting the number of files changed.
 159        Each changed file counts equally in the dirstat analysis. This is
 160        the computationally cheapest `--dirstat` behavior, since it does
 161        not have to look at the file contents at all.
 162`cumulative`;;
 163        Count changes in a child directory for the parent directory as well.
 164        Note that when using `cumulative`, the sum of the percentages
 165        reported may exceed 100%. The default (non-cumulative) behavior can
 166        be specified with the `noncumulative` parameter.
 167<limit>;;
 168        An integer parameter specifies a cut-off percent (3% by default).
 169        Directories contributing less than this percentage of the changes
 170        are not shown in the output.
 171--
 172+
 173Example: The following will count changed files, while ignoring
 174directories with less than 10% of the total amount of changed files,
 175and accumulating child directory counts in the parent directories:
 176`--dirstat=files,10,cumulative`.
 177
 178--summary::
 179        Output a condensed summary of extended header information
 180        such as creations, renames and mode changes.
 181
 182ifndef::git-format-patch[]
 183--patch-with-stat::
 184        Synonym for `-p --stat`.
 185endif::git-format-patch[]
 186
 187ifndef::git-format-patch[]
 188
 189-z::
 190ifdef::git-log[]
 191        Separate the commits with NULs instead of with new newlines.
 192+
 193Also, when `--raw` or `--numstat` has been given, do not munge
 194pathnames and use NULs as output field terminators.
 195endif::git-log[]
 196ifndef::git-log[]
 197        When `--raw`, `--numstat`, `--name-only` or `--name-status` has been
 198        given, do not munge pathnames and use NULs as output field terminators.
 199endif::git-log[]
 200+
 201Without this option, each pathname output will have TAB, LF, double quotes,
 202and backslash characters replaced with `\t`, `\n`, `\"`, and `\\`,
 203respectively, and the pathname will be enclosed in double quotes if
 204any of those replacements occurred.
 205
 206--name-only::
 207        Show only names of changed files.
 208
 209--name-status::
 210        Show only names and status of changed files. See the description
 211        of the `--diff-filter` option on what the status letters mean.
 212
 213--submodule[=<format>]::
 214        Specify how differences in submodules are shown.  When `--submodule`
 215        or `--submodule=log` is given, the 'log' format is used.  This format lists
 216        the commits in the range like linkgit:git-submodule[1] `summary` does.
 217        Omitting the `--submodule` option or specifying `--submodule=short`,
 218        uses the 'short' format. This format just shows the names of the commits
 219        at the beginning and end of the range.  Can be tweaked via the
 220        `diff.submodule` configuration variable.
 221
 222--color[=<when>]::
 223        Show colored diff.
 224        `--color` (i.e. without '=<when>') is the same as `--color=always`.
 225        '<when>' can be one of `always`, `never`, or `auto`.
 226ifdef::git-diff[]
 227        It can be changed by the `color.ui` and `color.diff`
 228        configuration settings.
 229endif::git-diff[]
 230
 231--no-color::
 232        Turn off colored diff.
 233ifdef::git-diff[]
 234        This can be used to override configuration settings.
 235endif::git-diff[]
 236        It is the same as `--color=never`.
 237
 238--word-diff[=<mode>]::
 239        Show a word diff, using the <mode> to delimit changed words.
 240        By default, words are delimited by whitespace; see
 241        `--word-diff-regex` below.  The <mode> defaults to 'plain', and
 242        must be one of:
 243+
 244--
 245color::
 246        Highlight changed words using only colors.  Implies `--color`.
 247plain::
 248        Show words as `[-removed-]` and `{+added+}`.  Makes no
 249        attempts to escape the delimiters if they appear in the input,
 250        so the output may be ambiguous.
 251porcelain::
 252        Use a special line-based format intended for script
 253        consumption.  Added/removed/unchanged runs are printed in the
 254        usual unified diff format, starting with a `+`/`-`/` `
 255        character at the beginning of the line and extending to the
 256        end of the line.  Newlines in the input are represented by a
 257        tilde `~` on a line of its own.
 258none::
 259        Disable word diff again.
 260--
 261+
 262Note that despite the name of the first mode, color is used to
 263highlight the changed parts in all modes if enabled.
 264
 265--word-diff-regex=<regex>::
 266        Use <regex> to decide what a word is, instead of considering
 267        runs of non-whitespace to be a word.  Also implies
 268        `--word-diff` unless it was already enabled.
 269+
 270Every non-overlapping match of the
 271<regex> is considered a word.  Anything between these matches is
 272considered whitespace and ignored(!) for the purposes of finding
 273differences.  You may want to append `|[^[:space:]]` to your regular
 274expression to make sure that it matches all non-whitespace characters.
 275A match that contains a newline is silently truncated(!) at the
 276newline.
 277+
 278For example, `--word-diff-regex=.` will treat each character as a word
 279and, correspondingly, show differences character by character.
 280+
 281The regex can also be set via a diff driver or configuration option, see
 282linkgit:gitattributes[5] or linkgit:git-config[1].  Giving it explicitly
 283overrides any diff driver or configuration setting.  Diff drivers
 284override configuration settings.
 285
 286--color-words[=<regex>]::
 287        Equivalent to `--word-diff=color` plus (if a regex was
 288        specified) `--word-diff-regex=<regex>`.
 289endif::git-format-patch[]
 290
 291--no-renames::
 292        Turn off rename detection, even when the configuration
 293        file gives the default to do so.
 294
 295ifndef::git-format-patch[]
 296--check::
 297        Warn if changes introduce conflict markers or whitespace errors.
 298        What are considered whitespace errors is controlled by `core.whitespace`
 299        configuration.  By default, trailing whitespaces (including
 300        lines that solely consist of whitespaces) and a space character
 301        that is immediately followed by a tab character inside the
 302        initial indent of the line are considered whitespace errors.
 303        Exits with non-zero status if problems are found. Not compatible
 304        with --exit-code.
 305
 306--ws-error-highlight=<kind>::
 307        Highlight whitespace errors on lines specified by <kind>
 308        in the color specified by `color.diff.whitespace`.  <kind>
 309        is a comma separated list of `old`, `new`, `context`.  When
 310        this option is not given, only whitespace errors in `new`
 311        lines are highlighted.  E.g. `--ws-error-highlight=new,old`
 312        highlights whitespace errors on both deleted and added lines.
 313        `all` can be used as a short-hand for `old,new,context`.
 314
 315endif::git-format-patch[]
 316
 317--full-index::
 318        Instead of the first handful of characters, show the full
 319        pre- and post-image blob object names on the "index"
 320        line when generating patch format output.
 321
 322--binary::
 323        In addition to `--full-index`, output a binary diff that
 324        can be applied with `git-apply`.
 325
 326--abbrev[=<n>]::
 327        Instead of showing the full 40-byte hexadecimal object
 328        name in diff-raw format output and diff-tree header
 329        lines, show only a partial prefix.  This is
 330        independent of the `--full-index` option above, which controls
 331        the diff-patch output format.  Non default number of
 332        digits can be specified with `--abbrev=<n>`.
 333
 334-B[<n>][/<m>]::
 335--break-rewrites[=[<n>][/<m>]]::
 336        Break complete rewrite changes into pairs of delete and
 337        create. This serves two purposes:
 338+
 339It affects the way a change that amounts to a total rewrite of a file
 340not as a series of deletion and insertion mixed together with a very
 341few lines that happen to match textually as the context, but as a
 342single deletion of everything old followed by a single insertion of
 343everything new, and the number `m` controls this aspect of the -B
 344option (defaults to 60%). `-B/70%` specifies that less than 30% of the
 345original should remain in the result for Git to consider it a total
 346rewrite (i.e. otherwise the resulting patch will be a series of
 347deletion and insertion mixed together with context lines).
 348+
 349When used with -M, a totally-rewritten file is also considered as the
 350source of a rename (usually -M only considers a file that disappeared
 351as the source of a rename), and the number `n` controls this aspect of
 352the -B option (defaults to 50%). `-B20%` specifies that a change with
 353addition and deletion compared to 20% or more of the file's size are
 354eligible for being picked up as a possible source of a rename to
 355another file.
 356
 357-M[<n>]::
 358--find-renames[=<n>]::
 359ifndef::git-log[]
 360        Detect renames.
 361endif::git-log[]
 362ifdef::git-log[]
 363        If generating diffs, detect and report renames for each commit.
 364        For following files across renames while traversing history, see
 365        `--follow`.
 366endif::git-log[]
 367        If `n` is specified, it is a threshold on the similarity
 368        index (i.e. amount of addition/deletions compared to the
 369        file's size). For example, `-M90%` means Git should consider a
 370        delete/add pair to be a rename if more than 90% of the file
 371        hasn't changed.  Without a `%` sign, the number is to be read as
 372        a fraction, with a decimal point before it.  I.e., `-M5` becomes
 373        0.5, and is thus the same as `-M50%`.  Similarly, `-M05` is
 374        the same as `-M5%`.  To limit detection to exact renames, use
 375        `-M100%`.  The default similarity index is 50%.
 376
 377-C[<n>]::
 378--find-copies[=<n>]::
 379        Detect copies as well as renames.  See also `--find-copies-harder`.
 380        If `n` is specified, it has the same meaning as for `-M<n>`.
 381
 382--find-copies-harder::
 383        For performance reasons, by default, `-C` option finds copies only
 384        if the original file of the copy was modified in the same
 385        changeset.  This flag makes the command
 386        inspect unmodified files as candidates for the source of
 387        copy.  This is a very expensive operation for large
 388        projects, so use it with caution.  Giving more than one
 389        `-C` option has the same effect.
 390
 391-D::
 392--irreversible-delete::
 393        Omit the preimage for deletes, i.e. print only the header but not
 394        the diff between the preimage and `/dev/null`. The resulting patch
 395        is not meant to be applied with `patch` or `git apply`; this is
 396        solely for people who want to just concentrate on reviewing the
 397        text after the change. In addition, the output obviously lack
 398        enough information to apply such a patch in reverse, even manually,
 399        hence the name of the option.
 400+
 401When used together with `-B`, omit also the preimage in the deletion part
 402of a delete/create pair.
 403
 404-l<num>::
 405        The `-M` and `-C` options require O(n^2) processing time where n
 406        is the number of potential rename/copy targets.  This
 407        option prevents rename/copy detection from running if
 408        the number of rename/copy targets exceeds the specified
 409        number.
 410
 411ifndef::git-format-patch[]
 412--diff-filter=[(A|C|D|M|R|T|U|X|B)...[*]]::
 413        Select only files that are Added (`A`), Copied (`C`),
 414        Deleted (`D`), Modified (`M`), Renamed (`R`), have their
 415        type (i.e. regular file, symlink, submodule, ...) changed (`T`),
 416        are Unmerged (`U`), are
 417        Unknown (`X`), or have had their pairing Broken (`B`).
 418        Any combination of the filter characters (including none) can be used.
 419        When `*` (All-or-none) is added to the combination, all
 420        paths are selected if there is any file that matches
 421        other criteria in the comparison; if there is no file
 422        that matches other criteria, nothing is selected.
 423
 424-S<string>::
 425        Look for differences that change the number of occurrences of
 426        the specified string (i.e. addition/deletion) in a file.
 427        Intended for the scripter's use.
 428+
 429It is useful when you're looking for an exact block of code (like a
 430struct), and want to know the history of that block since it first
 431came into being: use the feature iteratively to feed the interesting
 432block in the preimage back into `-S`, and keep going until you get the
 433very first version of the block.
 434
 435-G<regex>::
 436        Look for differences whose patch text contains added/removed
 437        lines that match <regex>.
 438+
 439To illustrate the difference between `-S<regex> --pickaxe-regex` and
 440`-G<regex>`, consider a commit with the following diff in the same
 441file:
 442+
 443----
 444+    return !regexec(regexp, two->ptr, 1, &regmatch, 0);
 445...
 446-    hit = !regexec(regexp, mf2.ptr, 1, &regmatch, 0);
 447----
 448+
 449While `git log -G"regexec\(regexp"` will show this commit, `git log
 450-S"regexec\(regexp" --pickaxe-regex` will not (because the number of
 451occurrences of that string did not change).
 452+
 453See the 'pickaxe' entry in linkgit:gitdiffcore[7] for more
 454information.
 455
 456--pickaxe-all::
 457        When `-S` or `-G` finds a change, show all the changes in that
 458        changeset, not just the files that contain the change
 459        in <string>.
 460
 461--pickaxe-regex::
 462        Treat the <string> given to `-S` as an extended POSIX regular
 463        expression to match.
 464endif::git-format-patch[]
 465
 466-O<orderfile>::
 467        Output the patch in the order specified in the
 468        <orderfile>, which has one shell glob pattern per line.
 469        This overrides the `diff.orderFile` configuration variable
 470        (see linkgit:git-config[1]).  To cancel `diff.orderFile`,
 471        use `-O/dev/null`.
 472
 473ifndef::git-format-patch[]
 474-R::
 475        Swap two inputs; that is, show differences from index or
 476        on-disk file to tree contents.
 477
 478--relative[=<path>]::
 479        When run from a subdirectory of the project, it can be
 480        told to exclude changes outside the directory and show
 481        pathnames relative to it with this option.  When you are
 482        not in a subdirectory (e.g. in a bare repository), you
 483        can name which subdirectory to make the output relative
 484        to by giving a <path> as an argument.
 485endif::git-format-patch[]
 486
 487-a::
 488--text::
 489        Treat all files as text.
 490
 491--ignore-space-at-eol::
 492        Ignore changes in whitespace at EOL.
 493
 494-b::
 495--ignore-space-change::
 496        Ignore changes in amount of whitespace.  This ignores whitespace
 497        at line end, and considers all other sequences of one or
 498        more whitespace characters to be equivalent.
 499
 500-w::
 501--ignore-all-space::
 502        Ignore whitespace when comparing lines.  This ignores
 503        differences even if one line has whitespace where the other
 504        line has none.
 505
 506--ignore-blank-lines::
 507        Ignore changes whose lines are all blank.
 508
 509--inter-hunk-context=<lines>::
 510        Show the context between diff hunks, up to the specified number
 511        of lines, thereby fusing hunks that are close to each other.
 512
 513-W::
 514--function-context::
 515        Show whole surrounding functions of changes.
 516
 517ifndef::git-format-patch[]
 518ifndef::git-log[]
 519--exit-code::
 520        Make the program exit with codes similar to diff(1).
 521        That is, it exits with 1 if there were differences and
 522        0 means no differences.
 523
 524--quiet::
 525        Disable all output of the program. Implies `--exit-code`.
 526endif::git-log[]
 527endif::git-format-patch[]
 528
 529--ext-diff::
 530        Allow an external diff helper to be executed. If you set an
 531        external diff driver with linkgit:gitattributes[5], you need
 532        to use this option with linkgit:git-log[1] and friends.
 533
 534--no-ext-diff::
 535        Disallow external diff drivers.
 536
 537--textconv::
 538--no-textconv::
 539        Allow (or disallow) external text conversion filters to be run
 540        when comparing binary files. See linkgit:gitattributes[5] for
 541        details. Because textconv filters are typically a one-way
 542        conversion, the resulting diff is suitable for human
 543        consumption, but cannot be applied. For this reason, textconv
 544        filters are enabled by default only for linkgit:git-diff[1] and
 545        linkgit:git-log[1], but not for linkgit:git-format-patch[1] or
 546        diff plumbing commands.
 547
 548--ignore-submodules[=<when>]::
 549        Ignore changes to submodules in the diff generation. <when> can be
 550        either "none", "untracked", "dirty" or "all", which is the default.
 551        Using "none" will consider the submodule modified when it either contains
 552        untracked or modified files or its HEAD differs from the commit recorded
 553        in the superproject and can be used to override any settings of the
 554        'ignore' option in linkgit:git-config[1] or linkgit:gitmodules[5]. When
 555        "untracked" is used submodules are not considered dirty when they only
 556        contain untracked content (but they are still scanned for modified
 557        content). Using "dirty" ignores all changes to the work tree of submodules,
 558        only changes to the commits stored in the superproject are shown (this was
 559        the behavior until 1.7.0). Using "all" hides all changes to submodules.
 560
 561--src-prefix=<prefix>::
 562        Show the given source prefix instead of "a/".
 563
 564--dst-prefix=<prefix>::
 565        Show the given destination prefix instead of "b/".
 566
 567--no-prefix::
 568        Do not show any source or destination prefix.
 569
 570For more detailed explanation on these common options, see also
 571linkgit:gitdiffcore[7].