Documentation / diff-options.txton commit t7415: don't bother creating commit for symlink test (431acd2)
   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        Enable the heuristic that shift diff hunk boundaries to make patches
  68        easier to read. This is the default.
  69
  70--no-indent-heuristic::
  71        Disable the indent heuristic.
  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--anchored=<text>::
  84        Generate a diff using the "anchored diff" algorithm.
  85+
  86This option may be specified more than once.
  87+
  88If a line exists in both the source and destination, exists only once,
  89and starts with this text, this algorithm attempts to prevent it from
  90appearing as a deletion or addition in the output. It uses the "patience
  91diff" algorithm internally.
  92
  93--diff-algorithm={patience|minimal|histogram|myers}::
  94        Choose a diff algorithm. The variants are as follows:
  95+
  96--
  97`default`, `myers`;;
  98        The basic greedy diff algorithm. Currently, this is the default.
  99`minimal`;;
 100        Spend extra time to make sure the smallest possible diff is
 101        produced.
 102`patience`;;
 103        Use "patience diff" algorithm when generating patches.
 104`histogram`;;
 105        This algorithm extends the patience algorithm to "support
 106        low-occurrence common elements".
 107--
 108+
 109For instance, if you configured diff.algorithm variable to a
 110non-default value and want to use the default one, then you
 111have to use `--diff-algorithm=default` option.
 112
 113--stat[=<width>[,<name-width>[,<count>]]]::
 114        Generate a diffstat. By default, as much space as necessary
 115        will be used for the filename part, and the rest for the graph
 116        part. Maximum width defaults to terminal width, or 80 columns
 117        if not connected to a terminal, and can be overridden by
 118        `<width>`. The width of the filename part can be limited by
 119        giving another width `<name-width>` after a comma. The width
 120        of the graph part can be limited by using
 121        `--stat-graph-width=<width>` (affects all commands generating
 122        a stat graph) or by setting `diff.statGraphWidth=<width>`
 123        (does not affect `git format-patch`).
 124        By giving a third parameter `<count>`, you can limit the
 125        output to the first `<count>` lines, followed by `...` if
 126        there are more.
 127+
 128These parameters can also be set individually with `--stat-width=<width>`,
 129`--stat-name-width=<name-width>` and `--stat-count=<count>`.
 130
 131--compact-summary::
 132        Output a condensed summary of extended header information such
 133        as file creations or deletions ("new" or "gone", optionally "+l"
 134        if it's a symlink) and mode changes ("+x" or "-x" for adding
 135        or removing executable bit respectively) in diffstat. The
 136        information is put betwen the filename part and the graph
 137        part. Implies `--stat`.
 138
 139--numstat::
 140        Similar to `--stat`, but shows number of added and
 141        deleted lines in decimal notation and pathname without
 142        abbreviation, to make it more machine friendly.  For
 143        binary files, outputs two `-` instead of saying
 144        `0 0`.
 145
 146--shortstat::
 147        Output only the last line of the `--stat` format containing total
 148        number of modified files, as well as number of added and deleted
 149        lines.
 150
 151--dirstat[=<param1,param2,...>]::
 152        Output the distribution of relative amount of changes for each
 153        sub-directory. The behavior of `--dirstat` can be customized by
 154        passing it a comma separated list of parameters.
 155        The defaults are controlled by the `diff.dirstat` configuration
 156        variable (see linkgit:git-config[1]).
 157        The following parameters are available:
 158+
 159--
 160`changes`;;
 161        Compute the dirstat numbers by counting the lines that have been
 162        removed from the source, or added to the destination. This ignores
 163        the amount of pure code movements within a file.  In other words,
 164        rearranging lines in a file is not counted as much as other changes.
 165        This is the default behavior when no parameter is given.
 166`lines`;;
 167        Compute the dirstat numbers by doing the regular line-based diff
 168        analysis, and summing the removed/added line counts. (For binary
 169        files, count 64-byte chunks instead, since binary files have no
 170        natural concept of lines). This is a more expensive `--dirstat`
 171        behavior than the `changes` behavior, but it does count rearranged
 172        lines within a file as much as other changes. The resulting output
 173        is consistent with what you get from the other `--*stat` options.
 174`files`;;
 175        Compute the dirstat numbers by counting the number of files changed.
 176        Each changed file counts equally in the dirstat analysis. This is
 177        the computationally cheapest `--dirstat` behavior, since it does
 178        not have to look at the file contents at all.
 179`cumulative`;;
 180        Count changes in a child directory for the parent directory as well.
 181        Note that when using `cumulative`, the sum of the percentages
 182        reported may exceed 100%. The default (non-cumulative) behavior can
 183        be specified with the `noncumulative` parameter.
 184<limit>;;
 185        An integer parameter specifies a cut-off percent (3% by default).
 186        Directories contributing less than this percentage of the changes
 187        are not shown in the output.
 188--
 189+
 190Example: The following will count changed files, while ignoring
 191directories with less than 10% of the total amount of changed files,
 192and accumulating child directory counts in the parent directories:
 193`--dirstat=files,10,cumulative`.
 194
 195--summary::
 196        Output a condensed summary of extended header information
 197        such as creations, renames and mode changes.
 198
 199ifndef::git-format-patch[]
 200--patch-with-stat::
 201        Synonym for `-p --stat`.
 202endif::git-format-patch[]
 203
 204ifndef::git-format-patch[]
 205
 206-z::
 207ifdef::git-log[]
 208        Separate the commits with NULs instead of with new newlines.
 209+
 210Also, when `--raw` or `--numstat` has been given, do not munge
 211pathnames and use NULs as output field terminators.
 212endif::git-log[]
 213ifndef::git-log[]
 214        When `--raw`, `--numstat`, `--name-only` or `--name-status` has been
 215        given, do not munge pathnames and use NULs as output field terminators.
 216endif::git-log[]
 217+
 218Without this option, pathnames with "unusual" characters are quoted as
 219explained for the configuration variable `core.quotePath` (see
 220linkgit:git-config[1]).
 221
 222--name-only::
 223        Show only names of changed files.
 224
 225--name-status::
 226        Show only names and status of changed files. See the description
 227        of the `--diff-filter` option on what the status letters mean.
 228
 229--submodule[=<format>]::
 230        Specify how differences in submodules are shown.  When specifying
 231        `--submodule=short` the 'short' format is used.  This format just
 232        shows the names of the commits at the beginning and end of the range.
 233        When `--submodule` or `--submodule=log` is specified, the 'log'
 234        format is used.  This format lists the commits in the range like
 235        linkgit:git-submodule[1] `summary` does.  When `--submodule=diff`
 236        is specified, the 'diff' format is used.  This format shows an
 237        inline diff of the changes in the submodule contents between the
 238        commit range.  Defaults to `diff.submodule` or the 'short' format
 239        if the config option is unset.
 240
 241--color[=<when>]::
 242        Show colored diff.
 243        `--color` (i.e. without '=<when>') is the same as `--color=always`.
 244        '<when>' can be one of `always`, `never`, or `auto`.
 245ifdef::git-diff[]
 246        It can be changed by the `color.ui` and `color.diff`
 247        configuration settings.
 248endif::git-diff[]
 249
 250--no-color::
 251        Turn off colored diff.
 252ifdef::git-diff[]
 253        This can be used to override configuration settings.
 254endif::git-diff[]
 255        It is the same as `--color=never`.
 256
 257--color-moved[=<mode>]::
 258        Moved lines of code are colored differently.
 259ifdef::git-diff[]
 260        It can be changed by the `diff.colorMoved` configuration setting.
 261endif::git-diff[]
 262        The <mode> defaults to 'no' if the option is not given
 263        and to 'zebra' if the option with no mode is given.
 264        The mode must be one of:
 265+
 266--
 267no::
 268        Moved lines are not highlighted.
 269default::
 270        Is a synonym for `zebra`. This may change to a more sensible mode
 271        in the future.
 272plain::
 273        Any line that is added in one location and was removed
 274        in another location will be colored with 'color.diff.newMoved'.
 275        Similarly 'color.diff.oldMoved' will be used for removed lines
 276        that are added somewhere else in the diff. This mode picks up any
 277        moved line, but it is not very useful in a review to determine
 278        if a block of code was moved without permutation.
 279zebra::
 280        Blocks of moved text of at least 20 alphanumeric characters
 281        are detected greedily. The detected blocks are
 282        painted using either the 'color.diff.{old,new}Moved' color or
 283        'color.diff.{old,new}MovedAlternative'. The change between
 284        the two colors indicates that a new block was detected.
 285dimmed_zebra::
 286        Similar to 'zebra', but additional dimming of uninteresting parts
 287        of moved code is performed. The bordering lines of two adjacent
 288        blocks are considered interesting, the rest is uninteresting.
 289--
 290
 291--word-diff[=<mode>]::
 292        Show a word diff, using the <mode> to delimit changed words.
 293        By default, words are delimited by whitespace; see
 294        `--word-diff-regex` below.  The <mode> defaults to 'plain', and
 295        must be one of:
 296+
 297--
 298color::
 299        Highlight changed words using only colors.  Implies `--color`.
 300plain::
 301        Show words as `[-removed-]` and `{+added+}`.  Makes no
 302        attempts to escape the delimiters if they appear in the input,
 303        so the output may be ambiguous.
 304porcelain::
 305        Use a special line-based format intended for script
 306        consumption.  Added/removed/unchanged runs are printed in the
 307        usual unified diff format, starting with a `+`/`-`/` `
 308        character at the beginning of the line and extending to the
 309        end of the line.  Newlines in the input are represented by a
 310        tilde `~` on a line of its own.
 311none::
 312        Disable word diff again.
 313--
 314+
 315Note that despite the name of the first mode, color is used to
 316highlight the changed parts in all modes if enabled.
 317
 318--word-diff-regex=<regex>::
 319        Use <regex> to decide what a word is, instead of considering
 320        runs of non-whitespace to be a word.  Also implies
 321        `--word-diff` unless it was already enabled.
 322+
 323Every non-overlapping match of the
 324<regex> is considered a word.  Anything between these matches is
 325considered whitespace and ignored(!) for the purposes of finding
 326differences.  You may want to append `|[^[:space:]]` to your regular
 327expression to make sure that it matches all non-whitespace characters.
 328A match that contains a newline is silently truncated(!) at the
 329newline.
 330+
 331For example, `--word-diff-regex=.` will treat each character as a word
 332and, correspondingly, show differences character by character.
 333+
 334The regex can also be set via a diff driver or configuration option, see
 335linkgit:gitattributes[5] or linkgit:git-config[1].  Giving it explicitly
 336overrides any diff driver or configuration setting.  Diff drivers
 337override configuration settings.
 338
 339--color-words[=<regex>]::
 340        Equivalent to `--word-diff=color` plus (if a regex was
 341        specified) `--word-diff-regex=<regex>`.
 342endif::git-format-patch[]
 343
 344--no-renames::
 345        Turn off rename detection, even when the configuration
 346        file gives the default to do so.
 347
 348ifndef::git-format-patch[]
 349--check::
 350        Warn if changes introduce conflict markers or whitespace errors.
 351        What are considered whitespace errors is controlled by `core.whitespace`
 352        configuration.  By default, trailing whitespaces (including
 353        lines that solely consist of whitespaces) and a space character
 354        that is immediately followed by a tab character inside the
 355        initial indent of the line are considered whitespace errors.
 356        Exits with non-zero status if problems are found. Not compatible
 357        with --exit-code.
 358
 359--ws-error-highlight=<kind>::
 360        Highlight whitespace errors in the `context`, `old` or `new`
 361        lines of the diff.  Multiple values are separated by comma,
 362        `none` resets previous values, `default` reset the list to
 363        `new` and `all` is a shorthand for `old,new,context`.  When
 364        this option is not given, and the configuration variable
 365        `diff.wsErrorHighlight` is not set, only whitespace errors in
 366        `new` lines are highlighted. The whitespace errors are colored
 367        whith `color.diff.whitespace`.
 368
 369endif::git-format-patch[]
 370
 371--full-index::
 372        Instead of the first handful of characters, show the full
 373        pre- and post-image blob object names on the "index"
 374        line when generating patch format output.
 375
 376--binary::
 377        In addition to `--full-index`, output a binary diff that
 378        can be applied with `git-apply`.
 379
 380--abbrev[=<n>]::
 381        Instead of showing the full 40-byte hexadecimal object
 382        name in diff-raw format output and diff-tree header
 383        lines, show only a partial prefix.  This is
 384        independent of the `--full-index` option above, which controls
 385        the diff-patch output format.  Non default number of
 386        digits can be specified with `--abbrev=<n>`.
 387
 388-B[<n>][/<m>]::
 389--break-rewrites[=[<n>][/<m>]]::
 390        Break complete rewrite changes into pairs of delete and
 391        create. This serves two purposes:
 392+
 393It affects the way a change that amounts to a total rewrite of a file
 394not as a series of deletion and insertion mixed together with a very
 395few lines that happen to match textually as the context, but as a
 396single deletion of everything old followed by a single insertion of
 397everything new, and the number `m` controls this aspect of the -B
 398option (defaults to 60%). `-B/70%` specifies that less than 30% of the
 399original should remain in the result for Git to consider it a total
 400rewrite (i.e. otherwise the resulting patch will be a series of
 401deletion and insertion mixed together with context lines).
 402+
 403When used with -M, a totally-rewritten file is also considered as the
 404source of a rename (usually -M only considers a file that disappeared
 405as the source of a rename), and the number `n` controls this aspect of
 406the -B option (defaults to 50%). `-B20%` specifies that a change with
 407addition and deletion compared to 20% or more of the file's size are
 408eligible for being picked up as a possible source of a rename to
 409another file.
 410
 411-M[<n>]::
 412--find-renames[=<n>]::
 413ifndef::git-log[]
 414        Detect renames.
 415endif::git-log[]
 416ifdef::git-log[]
 417        If generating diffs, detect and report renames for each commit.
 418        For following files across renames while traversing history, see
 419        `--follow`.
 420endif::git-log[]
 421        If `n` is specified, it is a threshold on the similarity
 422        index (i.e. amount of addition/deletions compared to the
 423        file's size). For example, `-M90%` means Git should consider a
 424        delete/add pair to be a rename if more than 90% of the file
 425        hasn't changed.  Without a `%` sign, the number is to be read as
 426        a fraction, with a decimal point before it.  I.e., `-M5` becomes
 427        0.5, and is thus the same as `-M50%`.  Similarly, `-M05` is
 428        the same as `-M5%`.  To limit detection to exact renames, use
 429        `-M100%`.  The default similarity index is 50%.
 430
 431-C[<n>]::
 432--find-copies[=<n>]::
 433        Detect copies as well as renames.  See also `--find-copies-harder`.
 434        If `n` is specified, it has the same meaning as for `-M<n>`.
 435
 436--find-copies-harder::
 437        For performance reasons, by default, `-C` option finds copies only
 438        if the original file of the copy was modified in the same
 439        changeset.  This flag makes the command
 440        inspect unmodified files as candidates for the source of
 441        copy.  This is a very expensive operation for large
 442        projects, so use it with caution.  Giving more than one
 443        `-C` option has the same effect.
 444
 445-D::
 446--irreversible-delete::
 447        Omit the preimage for deletes, i.e. print only the header but not
 448        the diff between the preimage and `/dev/null`. The resulting patch
 449        is not meant to be applied with `patch` or `git apply`; this is
 450        solely for people who want to just concentrate on reviewing the
 451        text after the change. In addition, the output obviously lacks
 452        enough information to apply such a patch in reverse, even manually,
 453        hence the name of the option.
 454+
 455When used together with `-B`, omit also the preimage in the deletion part
 456of a delete/create pair.
 457
 458-l<num>::
 459        The `-M` and `-C` options require O(n^2) processing time where n
 460        is the number of potential rename/copy targets.  This
 461        option prevents rename/copy detection from running if
 462        the number of rename/copy targets exceeds the specified
 463        number.
 464
 465ifndef::git-format-patch[]
 466--diff-filter=[(A|C|D|M|R|T|U|X|B)...[*]]::
 467        Select only files that are Added (`A`), Copied (`C`),
 468        Deleted (`D`), Modified (`M`), Renamed (`R`), have their
 469        type (i.e. regular file, symlink, submodule, ...) changed (`T`),
 470        are Unmerged (`U`), are
 471        Unknown (`X`), or have had their pairing Broken (`B`).
 472        Any combination of the filter characters (including none) can be used.
 473        When `*` (All-or-none) is added to the combination, all
 474        paths are selected if there is any file that matches
 475        other criteria in the comparison; if there is no file
 476        that matches other criteria, nothing is selected.
 477+
 478Also, these upper-case letters can be downcased to exclude.  E.g.
 479`--diff-filter=ad` excludes added and deleted paths.
 480+
 481Note that not all diffs can feature all types. For instance, diffs
 482from the index to the working tree can never have Added entries
 483(because the set of paths included in the diff is limited by what is in
 484the index).  Similarly, copied and renamed entries cannot appear if
 485detection for those types is disabled.
 486
 487-S<string>::
 488        Look for differences that change the number of occurrences of
 489        the specified string (i.e. addition/deletion) in a file.
 490        Intended for the scripter's use.
 491+
 492It is useful when you're looking for an exact block of code (like a
 493struct), and want to know the history of that block since it first
 494came into being: use the feature iteratively to feed the interesting
 495block in the preimage back into `-S`, and keep going until you get the
 496very first version of the block.
 497
 498-G<regex>::
 499        Look for differences whose patch text contains added/removed
 500        lines that match <regex>.
 501+
 502To illustrate the difference between `-S<regex> --pickaxe-regex` and
 503`-G<regex>`, consider a commit with the following diff in the same
 504file:
 505+
 506----
 507+    return !regexec(regexp, two->ptr, 1, &regmatch, 0);
 508...
 509-    hit = !regexec(regexp, mf2.ptr, 1, &regmatch, 0);
 510----
 511+
 512While `git log -G"regexec\(regexp"` will show this commit, `git log
 513-S"regexec\(regexp" --pickaxe-regex` will not (because the number of
 514occurrences of that string did not change).
 515+
 516See the 'pickaxe' entry in linkgit:gitdiffcore[7] for more
 517information.
 518
 519--find-object=<object-id>::
 520        Look for differences that change the number of occurrences of
 521        the specified object. Similar to `-S`, just the argument is different
 522        in that it doesn't search for a specific string but for a specific
 523        object id.
 524+
 525The object can be a blob or a submodule commit. It implies the `-t` option in
 526`git-log` to also find trees.
 527
 528--pickaxe-all::
 529        When `-S` or `-G` finds a change, show all the changes in that
 530        changeset, not just the files that contain the change
 531        in <string>.
 532
 533--pickaxe-regex::
 534        Treat the <string> given to `-S` as an extended POSIX regular
 535        expression to match.
 536
 537endif::git-format-patch[]
 538
 539-O<orderfile>::
 540        Control the order in which files appear in the output.
 541        This overrides the `diff.orderFile` configuration variable
 542        (see linkgit:git-config[1]).  To cancel `diff.orderFile`,
 543        use `-O/dev/null`.
 544+
 545The output order is determined by the order of glob patterns in
 546<orderfile>.
 547All files with pathnames that match the first pattern are output
 548first, all files with pathnames that match the second pattern (but not
 549the first) are output next, and so on.
 550All files with pathnames that do not match any pattern are output
 551last, as if there was an implicit match-all pattern at the end of the
 552file.
 553If multiple pathnames have the same rank (they match the same pattern
 554but no earlier patterns), their output order relative to each other is
 555the normal order.
 556+
 557<orderfile> is parsed as follows:
 558+
 559--
 560 - Blank lines are ignored, so they can be used as separators for
 561   readability.
 562
 563 - Lines starting with a hash ("`#`") are ignored, so they can be used
 564   for comments.  Add a backslash ("`\`") to the beginning of the
 565   pattern if it starts with a hash.
 566
 567 - Each other line contains a single pattern.
 568--
 569+
 570Patterns have the same syntax and semantics as patterns used for
 571fnmantch(3) without the FNM_PATHNAME flag, except a pathname also
 572matches a pattern if removing any number of the final pathname
 573components matches the pattern.  For example, the pattern "`foo*bar`"
 574matches "`fooasdfbar`" and "`foo/bar/baz/asdf`" but not "`foobarx`".
 575
 576ifndef::git-format-patch[]
 577-R::
 578        Swap two inputs; that is, show differences from index or
 579        on-disk file to tree contents.
 580
 581--relative[=<path>]::
 582        When run from a subdirectory of the project, it can be
 583        told to exclude changes outside the directory and show
 584        pathnames relative to it with this option.  When you are
 585        not in a subdirectory (e.g. in a bare repository), you
 586        can name which subdirectory to make the output relative
 587        to by giving a <path> as an argument.
 588endif::git-format-patch[]
 589
 590-a::
 591--text::
 592        Treat all files as text.
 593
 594--ignore-cr-at-eol::
 595        Ignore carrige-return at the end of line when doing a comparison.
 596
 597--ignore-space-at-eol::
 598        Ignore changes in whitespace at EOL.
 599
 600-b::
 601--ignore-space-change::
 602        Ignore changes in amount of whitespace.  This ignores whitespace
 603        at line end, and considers all other sequences of one or
 604        more whitespace characters to be equivalent.
 605
 606-w::
 607--ignore-all-space::
 608        Ignore whitespace when comparing lines.  This ignores
 609        differences even if one line has whitespace where the other
 610        line has none.
 611
 612--ignore-blank-lines::
 613        Ignore changes whose lines are all blank.
 614
 615--inter-hunk-context=<lines>::
 616        Show the context between diff hunks, up to the specified number
 617        of lines, thereby fusing hunks that are close to each other.
 618        Defaults to `diff.interHunkContext` or 0 if the config option
 619        is unset.
 620
 621-W::
 622--function-context::
 623        Show whole surrounding functions of changes.
 624
 625ifndef::git-format-patch[]
 626ifndef::git-log[]
 627--exit-code::
 628        Make the program exit with codes similar to diff(1).
 629        That is, it exits with 1 if there were differences and
 630        0 means no differences.
 631
 632--quiet::
 633        Disable all output of the program. Implies `--exit-code`.
 634endif::git-log[]
 635endif::git-format-patch[]
 636
 637--ext-diff::
 638        Allow an external diff helper to be executed. If you set an
 639        external diff driver with linkgit:gitattributes[5], you need
 640        to use this option with linkgit:git-log[1] and friends.
 641
 642--no-ext-diff::
 643        Disallow external diff drivers.
 644
 645--textconv::
 646--no-textconv::
 647        Allow (or disallow) external text conversion filters to be run
 648        when comparing binary files. See linkgit:gitattributes[5] for
 649        details. Because textconv filters are typically a one-way
 650        conversion, the resulting diff is suitable for human
 651        consumption, but cannot be applied. For this reason, textconv
 652        filters are enabled by default only for linkgit:git-diff[1] and
 653        linkgit:git-log[1], but not for linkgit:git-format-patch[1] or
 654        diff plumbing commands.
 655
 656--ignore-submodules[=<when>]::
 657        Ignore changes to submodules in the diff generation. <when> can be
 658        either "none", "untracked", "dirty" or "all", which is the default.
 659        Using "none" will consider the submodule modified when it either contains
 660        untracked or modified files or its HEAD differs from the commit recorded
 661        in the superproject and can be used to override any settings of the
 662        'ignore' option in linkgit:git-config[1] or linkgit:gitmodules[5]. When
 663        "untracked" is used submodules are not considered dirty when they only
 664        contain untracked content (but they are still scanned for modified
 665        content). Using "dirty" ignores all changes to the work tree of submodules,
 666        only changes to the commits stored in the superproject are shown (this was
 667        the behavior until 1.7.0). Using "all" hides all changes to submodules.
 668
 669--src-prefix=<prefix>::
 670        Show the given source prefix instead of "a/".
 671
 672--dst-prefix=<prefix>::
 673        Show the given destination prefix instead of "b/".
 674
 675--no-prefix::
 676        Do not show any source or destination prefix.
 677
 678--line-prefix=<prefix>::
 679        Prepend an additional prefix to every line of output.
 680
 681--ita-invisible-in-index::
 682        By default entries added by "git add -N" appear as an existing
 683        empty file in "git diff" and a new file in "git diff --cached".
 684        This option makes the entry appear as a new file in "git diff"
 685        and non-existent in "git diff --cached". This option could be
 686        reverted with `--ita-visible-in-index`. Both options are
 687        experimental and could be removed in future.
 688
 689For more detailed explanation on these common options, see also
 690linkgit:gitdiffcore[7].