Documentation / diff-options.txton commit Merge branch 'jk/avoid-unbounded-alloca' (269085e)
   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--compaction-heuristic::
  67--no-compaction-heuristic::
  68        These are to help debugging and tuning an experimental
  69        heuristic (which is off by default) that shifts the hunk
  70        boundary in an attempt to make the resulting patch easier
  71        to read.
  72
  73--minimal::
  74        Spend extra time to make sure the smallest possible
  75        diff is produced.
  76
  77--patience::
  78        Generate a diff using the "patience diff" algorithm.
  79
  80--histogram::
  81        Generate a diff using the "histogram diff" algorithm.
  82
  83--diff-algorithm={patience|minimal|histogram|myers}::
  84        Choose a diff algorithm. The variants are as follows:
  85+
  86--
  87`default`, `myers`;;
  88        The basic greedy diff algorithm. Currently, this is the default.
  89`minimal`;;
  90        Spend extra time to make sure the smallest possible diff is
  91        produced.
  92`patience`;;
  93        Use "patience diff" algorithm when generating patches.
  94`histogram`;;
  95        This algorithm extends the patience algorithm to "support
  96        low-occurrence common elements".
  97--
  98+
  99For instance, if you configured diff.algorithm variable to a
 100non-default value and want to use the default one, then you
 101have to use `--diff-algorithm=default` option.
 102
 103--stat[=<width>[,<name-width>[,<count>]]]::
 104        Generate a diffstat. By default, as much space as necessary
 105        will be used for the filename part, and the rest for the graph
 106        part. Maximum width defaults to terminal width, or 80 columns
 107        if not connected to a terminal, and can be overridden by
 108        `<width>`. The width of the filename part can be limited by
 109        giving another width `<name-width>` after a comma. The width
 110        of the graph part can be limited by using
 111        `--stat-graph-width=<width>` (affects all commands generating
 112        a stat graph) or by setting `diff.statGraphWidth=<width>`
 113        (does not affect `git format-patch`).
 114        By giving a third parameter `<count>`, you can limit the
 115        output to the first `<count>` lines, followed by `...` if
 116        there are more.
 117+
 118These parameters can also be set individually with `--stat-width=<width>`,
 119`--stat-name-width=<name-width>` and `--stat-count=<count>`.
 120
 121--numstat::
 122        Similar to `--stat`, but shows number of added and
 123        deleted lines in decimal notation and pathname without
 124        abbreviation, to make it more machine friendly.  For
 125        binary files, outputs two `-` instead of saying
 126        `0 0`.
 127
 128--shortstat::
 129        Output only the last line of the `--stat` format containing total
 130        number of modified files, as well as number of added and deleted
 131        lines.
 132
 133--dirstat[=<param1,param2,...>]::
 134        Output the distribution of relative amount of changes for each
 135        sub-directory. The behavior of `--dirstat` can be customized by
 136        passing it a comma separated list of parameters.
 137        The defaults are controlled by the `diff.dirstat` configuration
 138        variable (see linkgit:git-config[1]).
 139        The following parameters are available:
 140+
 141--
 142`changes`;;
 143        Compute the dirstat numbers by counting the lines that have been
 144        removed from the source, or added to the destination. This ignores
 145        the amount of pure code movements within a file.  In other words,
 146        rearranging lines in a file is not counted as much as other changes.
 147        This is the default behavior when no parameter is given.
 148`lines`;;
 149        Compute the dirstat numbers by doing the regular line-based diff
 150        analysis, and summing the removed/added line counts. (For binary
 151        files, count 64-byte chunks instead, since binary files have no
 152        natural concept of lines). This is a more expensive `--dirstat`
 153        behavior than the `changes` behavior, but it does count rearranged
 154        lines within a file as much as other changes. The resulting output
 155        is consistent with what you get from the other `--*stat` options.
 156`files`;;
 157        Compute the dirstat numbers by counting the number of files changed.
 158        Each changed file counts equally in the dirstat analysis. This is
 159        the computationally cheapest `--dirstat` behavior, since it does
 160        not have to look at the file contents at all.
 161`cumulative`;;
 162        Count changes in a child directory for the parent directory as well.
 163        Note that when using `cumulative`, the sum of the percentages
 164        reported may exceed 100%. The default (non-cumulative) behavior can
 165        be specified with the `noncumulative` parameter.
 166<limit>;;
 167        An integer parameter specifies a cut-off percent (3% by default).
 168        Directories contributing less than this percentage of the changes
 169        are not shown in the output.
 170--
 171+
 172Example: The following will count changed files, while ignoring
 173directories with less than 10% of the total amount of changed files,
 174and accumulating child directory counts in the parent directories:
 175`--dirstat=files,10,cumulative`.
 176
 177--summary::
 178        Output a condensed summary of extended header information
 179        such as creations, renames and mode changes.
 180
 181ifndef::git-format-patch[]
 182--patch-with-stat::
 183        Synonym for `-p --stat`.
 184endif::git-format-patch[]
 185
 186ifndef::git-format-patch[]
 187
 188-z::
 189ifdef::git-log[]
 190        Separate the commits with NULs instead of with new newlines.
 191+
 192Also, when `--raw` or `--numstat` has been given, do not munge
 193pathnames and use NULs as output field terminators.
 194endif::git-log[]
 195ifndef::git-log[]
 196        When `--raw`, `--numstat`, `--name-only` or `--name-status` has been
 197        given, do not munge pathnames and use NULs as output field terminators.
 198endif::git-log[]
 199+
 200Without this option, each pathname output will have TAB, LF, double quotes,
 201and backslash characters replaced with `\t`, `\n`, `\"`, and `\\`,
 202respectively, and the pathname will be enclosed in double quotes if
 203any of those replacements occurred.
 204
 205--name-only::
 206        Show only names of changed files.
 207
 208--name-status::
 209        Show only names and status of changed files. See the description
 210        of the `--diff-filter` option on what the status letters mean.
 211
 212--submodule[=<format>]::
 213        Specify how differences in submodules are shown.  When `--submodule`
 214        or `--submodule=log` is given, the 'log' format is used.  This format lists
 215        the commits in the range like linkgit:git-submodule[1] `summary` does.
 216        Omitting the `--submodule` option or specifying `--submodule=short`,
 217        uses the 'short' format. This format just shows the names of the commits
 218        at the beginning and end of the range.  Can be tweaked via the
 219        `diff.submodule` configuration variable.
 220
 221--color[=<when>]::
 222        Show colored diff.
 223        `--color` (i.e. without '=<when>') is the same as `--color=always`.
 224        '<when>' can be one of `always`, `never`, or `auto`.
 225ifdef::git-diff[]
 226        It can be changed by the `color.ui` and `color.diff`
 227        configuration settings.
 228endif::git-diff[]
 229
 230--no-color::
 231        Turn off colored diff.
 232ifdef::git-diff[]
 233        This can be used to override configuration settings.
 234endif::git-diff[]
 235        It is the same as `--color=never`.
 236
 237--word-diff[=<mode>]::
 238        Show a word diff, using the <mode> to delimit changed words.
 239        By default, words are delimited by whitespace; see
 240        `--word-diff-regex` below.  The <mode> defaults to 'plain', and
 241        must be one of:
 242+
 243--
 244color::
 245        Highlight changed words using only colors.  Implies `--color`.
 246plain::
 247        Show words as `[-removed-]` and `{+added+}`.  Makes no
 248        attempts to escape the delimiters if they appear in the input,
 249        so the output may be ambiguous.
 250porcelain::
 251        Use a special line-based format intended for script
 252        consumption.  Added/removed/unchanged runs are printed in the
 253        usual unified diff format, starting with a `+`/`-`/` `
 254        character at the beginning of the line and extending to the
 255        end of the line.  Newlines in the input are represented by a
 256        tilde `~` on a line of its own.
 257none::
 258        Disable word diff again.
 259--
 260+
 261Note that despite the name of the first mode, color is used to
 262highlight the changed parts in all modes if enabled.
 263
 264--word-diff-regex=<regex>::
 265        Use <regex> to decide what a word is, instead of considering
 266        runs of non-whitespace to be a word.  Also implies
 267        `--word-diff` unless it was already enabled.
 268+
 269Every non-overlapping match of the
 270<regex> is considered a word.  Anything between these matches is
 271considered whitespace and ignored(!) for the purposes of finding
 272differences.  You may want to append `|[^[:space:]]` to your regular
 273expression to make sure that it matches all non-whitespace characters.
 274A match that contains a newline is silently truncated(!) at the
 275newline.
 276+
 277For example, `--word-diff-regex=.` will treat each character as a word
 278and, correspondingly, show differences character by character.
 279+
 280The regex can also be set via a diff driver or configuration option, see
 281linkgit:gitattributes[5] or linkgit:git-config[1].  Giving it explicitly
 282overrides any diff driver or configuration setting.  Diff drivers
 283override configuration settings.
 284
 285--color-words[=<regex>]::
 286        Equivalent to `--word-diff=color` plus (if a regex was
 287        specified) `--word-diff-regex=<regex>`.
 288endif::git-format-patch[]
 289
 290--no-renames::
 291        Turn off rename detection, even when the configuration
 292        file gives the default to do so.
 293
 294ifndef::git-format-patch[]
 295--check::
 296        Warn if changes introduce conflict markers or whitespace errors.
 297        What are considered whitespace errors is controlled by `core.whitespace`
 298        configuration.  By default, trailing whitespaces (including
 299        lines that solely consist of whitespaces) and a space character
 300        that is immediately followed by a tab character inside the
 301        initial indent of the line are considered whitespace errors.
 302        Exits with non-zero status if problems are found. Not compatible
 303        with --exit-code.
 304
 305--ws-error-highlight=<kind>::
 306        Highlight whitespace errors on lines specified by <kind>
 307        in the color specified by `color.diff.whitespace`.  <kind>
 308        is a comma separated list of `old`, `new`, `context`.  When
 309        this option is not given, only whitespace errors in `new`
 310        lines are highlighted.  E.g. `--ws-error-highlight=new,old`
 311        highlights whitespace errors on both deleted and added lines.
 312        `all` can be used as a short-hand for `old,new,context`.
 313
 314endif::git-format-patch[]
 315
 316--full-index::
 317        Instead of the first handful of characters, show the full
 318        pre- and post-image blob object names on the "index"
 319        line when generating patch format output.
 320
 321--binary::
 322        In addition to `--full-index`, output a binary diff that
 323        can be applied with `git-apply`.
 324
 325--abbrev[=<n>]::
 326        Instead of showing the full 40-byte hexadecimal object
 327        name in diff-raw format output and diff-tree header
 328        lines, show only a partial prefix.  This is
 329        independent of the `--full-index` option above, which controls
 330        the diff-patch output format.  Non default number of
 331        digits can be specified with `--abbrev=<n>`.
 332
 333-B[<n>][/<m>]::
 334--break-rewrites[=[<n>][/<m>]]::
 335        Break complete rewrite changes into pairs of delete and
 336        create. This serves two purposes:
 337+
 338It affects the way a change that amounts to a total rewrite of a file
 339not as a series of deletion and insertion mixed together with a very
 340few lines that happen to match textually as the context, but as a
 341single deletion of everything old followed by a single insertion of
 342everything new, and the number `m` controls this aspect of the -B
 343option (defaults to 60%). `-B/70%` specifies that less than 30% of the
 344original should remain in the result for Git to consider it a total
 345rewrite (i.e. otherwise the resulting patch will be a series of
 346deletion and insertion mixed together with context lines).
 347+
 348When used with -M, a totally-rewritten file is also considered as the
 349source of a rename (usually -M only considers a file that disappeared
 350as the source of a rename), and the number `n` controls this aspect of
 351the -B option (defaults to 50%). `-B20%` specifies that a change with
 352addition and deletion compared to 20% or more of the file's size are
 353eligible for being picked up as a possible source of a rename to
 354another file.
 355
 356-M[<n>]::
 357--find-renames[=<n>]::
 358ifndef::git-log[]
 359        Detect renames.
 360endif::git-log[]
 361ifdef::git-log[]
 362        If generating diffs, detect and report renames for each commit.
 363        For following files across renames while traversing history, see
 364        `--follow`.
 365endif::git-log[]
 366        If `n` is specified, it is a threshold on the similarity
 367        index (i.e. amount of addition/deletions compared to the
 368        file's size). For example, `-M90%` means Git should consider a
 369        delete/add pair to be a rename if more than 90% of the file
 370        hasn't changed.  Without a `%` sign, the number is to be read as
 371        a fraction, with a decimal point before it.  I.e., `-M5` becomes
 372        0.5, and is thus the same as `-M50%`.  Similarly, `-M05` is
 373        the same as `-M5%`.  To limit detection to exact renames, use
 374        `-M100%`.  The default similarity index is 50%.
 375
 376-C[<n>]::
 377--find-copies[=<n>]::
 378        Detect copies as well as renames.  See also `--find-copies-harder`.
 379        If `n` is specified, it has the same meaning as for `-M<n>`.
 380
 381--find-copies-harder::
 382        For performance reasons, by default, `-C` option finds copies only
 383        if the original file of the copy was modified in the same
 384        changeset.  This flag makes the command
 385        inspect unmodified files as candidates for the source of
 386        copy.  This is a very expensive operation for large
 387        projects, so use it with caution.  Giving more than one
 388        `-C` option has the same effect.
 389
 390-D::
 391--irreversible-delete::
 392        Omit the preimage for deletes, i.e. print only the header but not
 393        the diff between the preimage and `/dev/null`. The resulting patch
 394        is not meant to be applied with `patch` or `git apply`; this is
 395        solely for people who want to just concentrate on reviewing the
 396        text after the change. In addition, the output obviously lack
 397        enough information to apply such a patch in reverse, even manually,
 398        hence the name of the option.
 399+
 400When used together with `-B`, omit also the preimage in the deletion part
 401of a delete/create pair.
 402
 403-l<num>::
 404        The `-M` and `-C` options require O(n^2) processing time where n
 405        is the number of potential rename/copy targets.  This
 406        option prevents rename/copy detection from running if
 407        the number of rename/copy targets exceeds the specified
 408        number.
 409
 410ifndef::git-format-patch[]
 411--diff-filter=[(A|C|D|M|R|T|U|X|B)...[*]]::
 412        Select only files that are Added (`A`), Copied (`C`),
 413        Deleted (`D`), Modified (`M`), Renamed (`R`), have their
 414        type (i.e. regular file, symlink, submodule, ...) changed (`T`),
 415        are Unmerged (`U`), are
 416        Unknown (`X`), or have had their pairing Broken (`B`).
 417        Any combination of the filter characters (including none) can be used.
 418        When `*` (All-or-none) is added to the combination, all
 419        paths are selected if there is any file that matches
 420        other criteria in the comparison; if there is no file
 421        that matches other criteria, nothing is selected.
 422
 423-S<string>::
 424        Look for differences that change the number of occurrences of
 425        the specified string (i.e. addition/deletion) in a file.
 426        Intended for the scripter's use.
 427+
 428It is useful when you're looking for an exact block of code (like a
 429struct), and want to know the history of that block since it first
 430came into being: use the feature iteratively to feed the interesting
 431block in the preimage back into `-S`, and keep going until you get the
 432very first version of the block.
 433
 434-G<regex>::
 435        Look for differences whose patch text contains added/removed
 436        lines that match <regex>.
 437+
 438To illustrate the difference between `-S<regex> --pickaxe-regex` and
 439`-G<regex>`, consider a commit with the following diff in the same
 440file:
 441+
 442----
 443+    return !regexec(regexp, two->ptr, 1, &regmatch, 0);
 444...
 445-    hit = !regexec(regexp, mf2.ptr, 1, &regmatch, 0);
 446----
 447+
 448While `git log -G"regexec\(regexp"` will show this commit, `git log
 449-S"regexec\(regexp" --pickaxe-regex` will not (because the number of
 450occurrences of that string did not change).
 451+
 452See the 'pickaxe' entry in linkgit:gitdiffcore[7] for more
 453information.
 454
 455--pickaxe-all::
 456        When `-S` or `-G` finds a change, show all the changes in that
 457        changeset, not just the files that contain the change
 458        in <string>.
 459
 460--pickaxe-regex::
 461        Treat the <string> given to `-S` as an extended POSIX regular
 462        expression to match.
 463endif::git-format-patch[]
 464
 465-O<orderfile>::
 466        Output the patch in the order specified in the
 467        <orderfile>, which has one shell glob pattern per line.
 468        This overrides the `diff.orderFile` configuration variable
 469        (see linkgit:git-config[1]).  To cancel `diff.orderFile`,
 470        use `-O/dev/null`.
 471
 472ifndef::git-format-patch[]
 473-R::
 474        Swap two inputs; that is, show differences from index or
 475        on-disk file to tree contents.
 476
 477--relative[=<path>]::
 478        When run from a subdirectory of the project, it can be
 479        told to exclude changes outside the directory and show
 480        pathnames relative to it with this option.  When you are
 481        not in a subdirectory (e.g. in a bare repository), you
 482        can name which subdirectory to make the output relative
 483        to by giving a <path> as an argument.
 484endif::git-format-patch[]
 485
 486-a::
 487--text::
 488        Treat all files as text.
 489
 490--ignore-space-at-eol::
 491        Ignore changes in whitespace at EOL.
 492
 493-b::
 494--ignore-space-change::
 495        Ignore changes in amount of whitespace.  This ignores whitespace
 496        at line end, and considers all other sequences of one or
 497        more whitespace characters to be equivalent.
 498
 499-w::
 500--ignore-all-space::
 501        Ignore whitespace when comparing lines.  This ignores
 502        differences even if one line has whitespace where the other
 503        line has none.
 504
 505--ignore-blank-lines::
 506        Ignore changes whose lines are all blank.
 507
 508--inter-hunk-context=<lines>::
 509        Show the context between diff hunks, up to the specified number
 510        of lines, thereby fusing hunks that are close to each other.
 511
 512-W::
 513--function-context::
 514        Show whole surrounding functions of changes.
 515
 516ifndef::git-format-patch[]
 517ifndef::git-log[]
 518--exit-code::
 519        Make the program exit with codes similar to diff(1).
 520        That is, it exits with 1 if there were differences and
 521        0 means no differences.
 522
 523--quiet::
 524        Disable all output of the program. Implies `--exit-code`.
 525endif::git-log[]
 526endif::git-format-patch[]
 527
 528--ext-diff::
 529        Allow an external diff helper to be executed. If you set an
 530        external diff driver with linkgit:gitattributes[5], you need
 531        to use this option with linkgit:git-log[1] and friends.
 532
 533--no-ext-diff::
 534        Disallow external diff drivers.
 535
 536--textconv::
 537--no-textconv::
 538        Allow (or disallow) external text conversion filters to be run
 539        when comparing binary files. See linkgit:gitattributes[5] for
 540        details. Because textconv filters are typically a one-way
 541        conversion, the resulting diff is suitable for human
 542        consumption, but cannot be applied. For this reason, textconv
 543        filters are enabled by default only for linkgit:git-diff[1] and
 544        linkgit:git-log[1], but not for linkgit:git-format-patch[1] or
 545        diff plumbing commands.
 546
 547--ignore-submodules[=<when>]::
 548        Ignore changes to submodules in the diff generation. <when> can be
 549        either "none", "untracked", "dirty" or "all", which is the default.
 550        Using "none" will consider the submodule modified when it either contains
 551        untracked or modified files or its HEAD differs from the commit recorded
 552        in the superproject and can be used to override any settings of the
 553        'ignore' option in linkgit:git-config[1] or linkgit:gitmodules[5]. When
 554        "untracked" is used submodules are not considered dirty when they only
 555        contain untracked content (but they are still scanned for modified
 556        content). Using "dirty" ignores all changes to the work tree of submodules,
 557        only changes to the commits stored in the superproject are shown (this was
 558        the behavior until 1.7.0). Using "all" hides all changes to submodules.
 559
 560--src-prefix=<prefix>::
 561        Show the given source prefix instead of "a/".
 562
 563--dst-prefix=<prefix>::
 564        Show the given destination prefix instead of "b/".
 565
 566--no-prefix::
 567        Do not show any source or destination prefix.
 568
 569For more detailed explanation on these common options, see also
 570linkgit:gitdiffcore[7].