Documentation / diff-options.txton commit blame: honor the diff heuristic options and config (5b16287)
   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
  66include::diff-heuristic-options.txt[]
  67
  68--minimal::
  69        Spend extra time to make sure the smallest possible
  70        diff is produced.
  71
  72--patience::
  73        Generate a diff using the "patience diff" algorithm.
  74
  75--histogram::
  76        Generate a diff using the "histogram diff" algorithm.
  77
  78--diff-algorithm={patience|minimal|histogram|myers}::
  79        Choose a diff algorithm. The variants are as follows:
  80+
  81--
  82`default`, `myers`;;
  83        The basic greedy diff algorithm. Currently, this is the default.
  84`minimal`;;
  85        Spend extra time to make sure the smallest possible diff is
  86        produced.
  87`patience`;;
  88        Use "patience diff" algorithm when generating patches.
  89`histogram`;;
  90        This algorithm extends the patience algorithm to "support
  91        low-occurrence common elements".
  92--
  93+
  94For instance, if you configured diff.algorithm variable to a
  95non-default value and want to use the default one, then you
  96have to use `--diff-algorithm=default` option.
  97
  98--stat[=<width>[,<name-width>[,<count>]]]::
  99        Generate a diffstat. By default, as much space as necessary
 100        will be used for the filename part, and the rest for the graph
 101        part. Maximum width defaults to terminal width, or 80 columns
 102        if not connected to a terminal, and can be overridden by
 103        `<width>`. The width of the filename part can be limited by
 104        giving another width `<name-width>` after a comma. The width
 105        of the graph part can be limited by using
 106        `--stat-graph-width=<width>` (affects all commands generating
 107        a stat graph) or by setting `diff.statGraphWidth=<width>`
 108        (does not affect `git format-patch`).
 109        By giving a third parameter `<count>`, you can limit the
 110        output to the first `<count>` lines, followed by `...` if
 111        there are more.
 112+
 113These parameters can also be set individually with `--stat-width=<width>`,
 114`--stat-name-width=<name-width>` and `--stat-count=<count>`.
 115
 116--numstat::
 117        Similar to `--stat`, but shows number of added and
 118        deleted lines in decimal notation and pathname without
 119        abbreviation, to make it more machine friendly.  For
 120        binary files, outputs two `-` instead of saying
 121        `0 0`.
 122
 123--shortstat::
 124        Output only the last line of the `--stat` format containing total
 125        number of modified files, as well as number of added and deleted
 126        lines.
 127
 128--dirstat[=<param1,param2,...>]::
 129        Output the distribution of relative amount of changes for each
 130        sub-directory. The behavior of `--dirstat` can be customized by
 131        passing it a comma separated list of parameters.
 132        The defaults are controlled by the `diff.dirstat` configuration
 133        variable (see linkgit:git-config[1]).
 134        The following parameters are available:
 135+
 136--
 137`changes`;;
 138        Compute the dirstat numbers by counting the lines that have been
 139        removed from the source, or added to the destination. This ignores
 140        the amount of pure code movements within a file.  In other words,
 141        rearranging lines in a file is not counted as much as other changes.
 142        This is the default behavior when no parameter is given.
 143`lines`;;
 144        Compute the dirstat numbers by doing the regular line-based diff
 145        analysis, and summing the removed/added line counts. (For binary
 146        files, count 64-byte chunks instead, since binary files have no
 147        natural concept of lines). This is a more expensive `--dirstat`
 148        behavior than the `changes` behavior, but it does count rearranged
 149        lines within a file as much as other changes. The resulting output
 150        is consistent with what you get from the other `--*stat` options.
 151`files`;;
 152        Compute the dirstat numbers by counting the number of files changed.
 153        Each changed file counts equally in the dirstat analysis. This is
 154        the computationally cheapest `--dirstat` behavior, since it does
 155        not have to look at the file contents at all.
 156`cumulative`;;
 157        Count changes in a child directory for the parent directory as well.
 158        Note that when using `cumulative`, the sum of the percentages
 159        reported may exceed 100%. The default (non-cumulative) behavior can
 160        be specified with the `noncumulative` parameter.
 161<limit>;;
 162        An integer parameter specifies a cut-off percent (3% by default).
 163        Directories contributing less than this percentage of the changes
 164        are not shown in the output.
 165--
 166+
 167Example: The following will count changed files, while ignoring
 168directories with less than 10% of the total amount of changed files,
 169and accumulating child directory counts in the parent directories:
 170`--dirstat=files,10,cumulative`.
 171
 172--summary::
 173        Output a condensed summary of extended header information
 174        such as creations, renames and mode changes.
 175
 176ifndef::git-format-patch[]
 177--patch-with-stat::
 178        Synonym for `-p --stat`.
 179endif::git-format-patch[]
 180
 181ifndef::git-format-patch[]
 182
 183-z::
 184ifdef::git-log[]
 185        Separate the commits with NULs instead of with new newlines.
 186+
 187Also, when `--raw` or `--numstat` has been given, do not munge
 188pathnames and use NULs as output field terminators.
 189endif::git-log[]
 190ifndef::git-log[]
 191        When `--raw`, `--numstat`, `--name-only` or `--name-status` has been
 192        given, do not munge pathnames and use NULs as output field terminators.
 193endif::git-log[]
 194+
 195Without this option, each pathname output will have TAB, LF, double quotes,
 196and backslash characters replaced with `\t`, `\n`, `\"`, and `\\`,
 197respectively, and the pathname will be enclosed in double quotes if
 198any of those replacements occurred.
 199
 200--name-only::
 201        Show only names of changed files.
 202
 203--name-status::
 204        Show only names and status of changed files. See the description
 205        of the `--diff-filter` option on what the status letters mean.
 206
 207--submodule[=<format>]::
 208        Specify how differences in submodules are shown.  When `--submodule`
 209        or `--submodule=log` is given, the 'log' format is used.  This format lists
 210        the commits in the range like linkgit:git-submodule[1] `summary` does.
 211        Omitting the `--submodule` option or specifying `--submodule=short`,
 212        uses the 'short' format. This format just shows the names of the commits
 213        at the beginning and end of the range.  Can be tweaked via the
 214        `diff.submodule` configuration variable.
 215
 216--color[=<when>]::
 217        Show colored diff.
 218        `--color` (i.e. without '=<when>') is the same as `--color=always`.
 219        '<when>' can be one of `always`, `never`, or `auto`.
 220ifdef::git-diff[]
 221        It can be changed by the `color.ui` and `color.diff`
 222        configuration settings.
 223endif::git-diff[]
 224
 225--no-color::
 226        Turn off colored diff.
 227ifdef::git-diff[]
 228        This can be used to override configuration settings.
 229endif::git-diff[]
 230        It is the same as `--color=never`.
 231
 232--word-diff[=<mode>]::
 233        Show a word diff, using the <mode> to delimit changed words.
 234        By default, words are delimited by whitespace; see
 235        `--word-diff-regex` below.  The <mode> defaults to 'plain', and
 236        must be one of:
 237+
 238--
 239color::
 240        Highlight changed words using only colors.  Implies `--color`.
 241plain::
 242        Show words as `[-removed-]` and `{+added+}`.  Makes no
 243        attempts to escape the delimiters if they appear in the input,
 244        so the output may be ambiguous.
 245porcelain::
 246        Use a special line-based format intended for script
 247        consumption.  Added/removed/unchanged runs are printed in the
 248        usual unified diff format, starting with a `+`/`-`/` `
 249        character at the beginning of the line and extending to the
 250        end of the line.  Newlines in the input are represented by a
 251        tilde `~` on a line of its own.
 252none::
 253        Disable word diff again.
 254--
 255+
 256Note that despite the name of the first mode, color is used to
 257highlight the changed parts in all modes if enabled.
 258
 259--word-diff-regex=<regex>::
 260        Use <regex> to decide what a word is, instead of considering
 261        runs of non-whitespace to be a word.  Also implies
 262        `--word-diff` unless it was already enabled.
 263+
 264Every non-overlapping match of the
 265<regex> is considered a word.  Anything between these matches is
 266considered whitespace and ignored(!) for the purposes of finding
 267differences.  You may want to append `|[^[:space:]]` to your regular
 268expression to make sure that it matches all non-whitespace characters.
 269A match that contains a newline is silently truncated(!) at the
 270newline.
 271+
 272For example, `--word-diff-regex=.` will treat each character as a word
 273and, correspondingly, show differences character by character.
 274+
 275The regex can also be set via a diff driver or configuration option, see
 276linkgit:gitattributes[5] or linkgit:git-config[1].  Giving it explicitly
 277overrides any diff driver or configuration setting.  Diff drivers
 278override configuration settings.
 279
 280--color-words[=<regex>]::
 281        Equivalent to `--word-diff=color` plus (if a regex was
 282        specified) `--word-diff-regex=<regex>`.
 283endif::git-format-patch[]
 284
 285--no-renames::
 286        Turn off rename detection, even when the configuration
 287        file gives the default to do so.
 288
 289ifndef::git-format-patch[]
 290--check::
 291        Warn if changes introduce conflict markers or whitespace errors.
 292        What are considered whitespace errors is controlled by `core.whitespace`
 293        configuration.  By default, trailing whitespaces (including
 294        lines that solely consist of whitespaces) and a space character
 295        that is immediately followed by a tab character inside the
 296        initial indent of the line are considered whitespace errors.
 297        Exits with non-zero status if problems are found. Not compatible
 298        with --exit-code.
 299
 300--ws-error-highlight=<kind>::
 301        Highlight whitespace errors on lines specified by <kind>
 302        in the color specified by `color.diff.whitespace`.  <kind>
 303        is a comma separated list of `old`, `new`, `context`.  When
 304        this option is not given, only whitespace errors in `new`
 305        lines are highlighted.  E.g. `--ws-error-highlight=new,old`
 306        highlights whitespace errors on both deleted and added lines.
 307        `all` can be used as a short-hand for `old,new,context`.
 308
 309endif::git-format-patch[]
 310
 311--full-index::
 312        Instead of the first handful of characters, show the full
 313        pre- and post-image blob object names on the "index"
 314        line when generating patch format output.
 315
 316--binary::
 317        In addition to `--full-index`, output a binary diff that
 318        can be applied with `git-apply`.
 319
 320--abbrev[=<n>]::
 321        Instead of showing the full 40-byte hexadecimal object
 322        name in diff-raw format output and diff-tree header
 323        lines, show only a partial prefix.  This is
 324        independent of the `--full-index` option above, which controls
 325        the diff-patch output format.  Non default number of
 326        digits can be specified with `--abbrev=<n>`.
 327
 328-B[<n>][/<m>]::
 329--break-rewrites[=[<n>][/<m>]]::
 330        Break complete rewrite changes into pairs of delete and
 331        create. This serves two purposes:
 332+
 333It affects the way a change that amounts to a total rewrite of a file
 334not as a series of deletion and insertion mixed together with a very
 335few lines that happen to match textually as the context, but as a
 336single deletion of everything old followed by a single insertion of
 337everything new, and the number `m` controls this aspect of the -B
 338option (defaults to 60%). `-B/70%` specifies that less than 30% of the
 339original should remain in the result for Git to consider it a total
 340rewrite (i.e. otherwise the resulting patch will be a series of
 341deletion and insertion mixed together with context lines).
 342+
 343When used with -M, a totally-rewritten file is also considered as the
 344source of a rename (usually -M only considers a file that disappeared
 345as the source of a rename), and the number `n` controls this aspect of
 346the -B option (defaults to 50%). `-B20%` specifies that a change with
 347addition and deletion compared to 20% or more of the file's size are
 348eligible for being picked up as a possible source of a rename to
 349another file.
 350
 351-M[<n>]::
 352--find-renames[=<n>]::
 353ifndef::git-log[]
 354        Detect renames.
 355endif::git-log[]
 356ifdef::git-log[]
 357        If generating diffs, detect and report renames for each commit.
 358        For following files across renames while traversing history, see
 359        `--follow`.
 360endif::git-log[]
 361        If `n` is specified, it is a threshold on the similarity
 362        index (i.e. amount of addition/deletions compared to the
 363        file's size). For example, `-M90%` means Git should consider a
 364        delete/add pair to be a rename if more than 90% of the file
 365        hasn't changed.  Without a `%` sign, the number is to be read as
 366        a fraction, with a decimal point before it.  I.e., `-M5` becomes
 367        0.5, and is thus the same as `-M50%`.  Similarly, `-M05` is
 368        the same as `-M5%`.  To limit detection to exact renames, use
 369        `-M100%`.  The default similarity index is 50%.
 370
 371-C[<n>]::
 372--find-copies[=<n>]::
 373        Detect copies as well as renames.  See also `--find-copies-harder`.
 374        If `n` is specified, it has the same meaning as for `-M<n>`.
 375
 376--find-copies-harder::
 377        For performance reasons, by default, `-C` option finds copies only
 378        if the original file of the copy was modified in the same
 379        changeset.  This flag makes the command
 380        inspect unmodified files as candidates for the source of
 381        copy.  This is a very expensive operation for large
 382        projects, so use it with caution.  Giving more than one
 383        `-C` option has the same effect.
 384
 385-D::
 386--irreversible-delete::
 387        Omit the preimage for deletes, i.e. print only the header but not
 388        the diff between the preimage and `/dev/null`. The resulting patch
 389        is not meant to be applied with `patch` or `git apply`; this is
 390        solely for people who want to just concentrate on reviewing the
 391        text after the change. In addition, the output obviously lack
 392        enough information to apply such a patch in reverse, even manually,
 393        hence the name of the option.
 394+
 395When used together with `-B`, omit also the preimage in the deletion part
 396of a delete/create pair.
 397
 398-l<num>::
 399        The `-M` and `-C` options require O(n^2) processing time where n
 400        is the number of potential rename/copy targets.  This
 401        option prevents rename/copy detection from running if
 402        the number of rename/copy targets exceeds the specified
 403        number.
 404
 405ifndef::git-format-patch[]
 406--diff-filter=[(A|C|D|M|R|T|U|X|B)...[*]]::
 407        Select only files that are Added (`A`), Copied (`C`),
 408        Deleted (`D`), Modified (`M`), Renamed (`R`), have their
 409        type (i.e. regular file, symlink, submodule, ...) changed (`T`),
 410        are Unmerged (`U`), are
 411        Unknown (`X`), or have had their pairing Broken (`B`).
 412        Any combination of the filter characters (including none) can be used.
 413        When `*` (All-or-none) is added to the combination, all
 414        paths are selected if there is any file that matches
 415        other criteria in the comparison; if there is no file
 416        that matches other criteria, nothing is selected.
 417
 418-S<string>::
 419        Look for differences that change the number of occurrences of
 420        the specified string (i.e. addition/deletion) in a file.
 421        Intended for the scripter's use.
 422+
 423It is useful when you're looking for an exact block of code (like a
 424struct), and want to know the history of that block since it first
 425came into being: use the feature iteratively to feed the interesting
 426block in the preimage back into `-S`, and keep going until you get the
 427very first version of the block.
 428
 429-G<regex>::
 430        Look for differences whose patch text contains added/removed
 431        lines that match <regex>.
 432+
 433To illustrate the difference between `-S<regex> --pickaxe-regex` and
 434`-G<regex>`, consider a commit with the following diff in the same
 435file:
 436+
 437----
 438+    return !regexec(regexp, two->ptr, 1, &regmatch, 0);
 439...
 440-    hit = !regexec(regexp, mf2.ptr, 1, &regmatch, 0);
 441----
 442+
 443While `git log -G"regexec\(regexp"` will show this commit, `git log
 444-S"regexec\(regexp" --pickaxe-regex` will not (because the number of
 445occurrences of that string did not change).
 446+
 447See the 'pickaxe' entry in linkgit:gitdiffcore[7] for more
 448information.
 449
 450--pickaxe-all::
 451        When `-S` or `-G` finds a change, show all the changes in that
 452        changeset, not just the files that contain the change
 453        in <string>.
 454
 455--pickaxe-regex::
 456        Treat the <string> given to `-S` as an extended POSIX regular
 457        expression to match.
 458endif::git-format-patch[]
 459
 460-O<orderfile>::
 461        Output the patch in the order specified in the
 462        <orderfile>, which has one shell glob pattern per line.
 463        This overrides the `diff.orderFile` configuration variable
 464        (see linkgit:git-config[1]).  To cancel `diff.orderFile`,
 465        use `-O/dev/null`.
 466
 467ifndef::git-format-patch[]
 468-R::
 469        Swap two inputs; that is, show differences from index or
 470        on-disk file to tree contents.
 471
 472--relative[=<path>]::
 473        When run from a subdirectory of the project, it can be
 474        told to exclude changes outside the directory and show
 475        pathnames relative to it with this option.  When you are
 476        not in a subdirectory (e.g. in a bare repository), you
 477        can name which subdirectory to make the output relative
 478        to by giving a <path> as an argument.
 479endif::git-format-patch[]
 480
 481-a::
 482--text::
 483        Treat all files as text.
 484
 485--ignore-space-at-eol::
 486        Ignore changes in whitespace at EOL.
 487
 488-b::
 489--ignore-space-change::
 490        Ignore changes in amount of whitespace.  This ignores whitespace
 491        at line end, and considers all other sequences of one or
 492        more whitespace characters to be equivalent.
 493
 494-w::
 495--ignore-all-space::
 496        Ignore whitespace when comparing lines.  This ignores
 497        differences even if one line has whitespace where the other
 498        line has none.
 499
 500--ignore-blank-lines::
 501        Ignore changes whose lines are all blank.
 502
 503--inter-hunk-context=<lines>::
 504        Show the context between diff hunks, up to the specified number
 505        of lines, thereby fusing hunks that are close to each other.
 506
 507-W::
 508--function-context::
 509        Show whole surrounding functions of changes.
 510
 511ifndef::git-format-patch[]
 512ifndef::git-log[]
 513--exit-code::
 514        Make the program exit with codes similar to diff(1).
 515        That is, it exits with 1 if there were differences and
 516        0 means no differences.
 517
 518--quiet::
 519        Disable all output of the program. Implies `--exit-code`.
 520endif::git-log[]
 521endif::git-format-patch[]
 522
 523--ext-diff::
 524        Allow an external diff helper to be executed. If you set an
 525        external diff driver with linkgit:gitattributes[5], you need
 526        to use this option with linkgit:git-log[1] and friends.
 527
 528--no-ext-diff::
 529        Disallow external diff drivers.
 530
 531--textconv::
 532--no-textconv::
 533        Allow (or disallow) external text conversion filters to be run
 534        when comparing binary files. See linkgit:gitattributes[5] for
 535        details. Because textconv filters are typically a one-way
 536        conversion, the resulting diff is suitable for human
 537        consumption, but cannot be applied. For this reason, textconv
 538        filters are enabled by default only for linkgit:git-diff[1] and
 539        linkgit:git-log[1], but not for linkgit:git-format-patch[1] or
 540        diff plumbing commands.
 541
 542--ignore-submodules[=<when>]::
 543        Ignore changes to submodules in the diff generation. <when> can be
 544        either "none", "untracked", "dirty" or "all", which is the default.
 545        Using "none" will consider the submodule modified when it either contains
 546        untracked or modified files or its HEAD differs from the commit recorded
 547        in the superproject and can be used to override any settings of the
 548        'ignore' option in linkgit:git-config[1] or linkgit:gitmodules[5]. When
 549        "untracked" is used submodules are not considered dirty when they only
 550        contain untracked content (but they are still scanned for modified
 551        content). Using "dirty" ignores all changes to the work tree of submodules,
 552        only changes to the commits stored in the superproject are shown (this was
 553        the behavior until 1.7.0). Using "all" hides all changes to submodules.
 554
 555--src-prefix=<prefix>::
 556        Show the given source prefix instead of "a/".
 557
 558--dst-prefix=<prefix>::
 559        Show the given destination prefix instead of "b/".
 560
 561--no-prefix::
 562        Do not show any source or destination prefix.
 563
 564For more detailed explanation on these common options, see also
 565linkgit:gitdiffcore[7].