GIT-DIFF-FILES(1)

🎀 NAME 🎀

okay so bestie, this is GIT-DIFF-FILES(1), fresh from the Git Manual, and the command is git-diff-files — it compares files in the working tree and the index. That’s the whole vibe. 🦋

✨ SYNOPSIS ✨

# 💖 DESCRIPTION 💖

It compares the files in the working tree and the index. When paths are specified, it compares only those named paths. Otherwise, all entries in the index are compared. The output format is the same as for `git diff-index` and `git diff-tree`. 💅

# 💅 OPTIONS 💅

- **`-p`, `-u`, `--patch`** — generate patch (see the section called “GENERATING PATCH TEXT WITH -P”).

- **`-s`, `--no-patch`** — suppress all output from the diff machinery. Useful for commands like `git show` that show the patch by default, so you can squelch their output, or to cancel the effect of options like `--patch`, `--stat` earlier on the command line in an alias. 🫶

- **`-U<n>`, `--unified=<n>`** — generate diffs with `<n>` lines of context. The number of context lines defaults to `diff.context`, or `3` if the configuration variable is unset. (`-U` without `<n>` is silently accepted as a synonym for `-p` due to a historical accident). Implies `--patch`.

- **`--output=<file>`** — output to a specific file instead of `stdout`.

- **`--output-indicator-new=<char>`** — specify the character used to indicate new lines in the generated patch. Normally it is `+`.

- **`--output-indicator-old=<char>`** — specify the character used to indicate old lines in the generated patch. Normally it is `-`.

- **`--output-indicator-context=<char>`** — specify the character used to indicate context lines in the generated patch. Normally it is `' '`.

- **`--raw`** — generate the diff in raw format. This is the default.

- **`--patch-with-raw`** — synonym for `-p --raw`.

- **`--indent-heuristic`** — enable the heuristic that shifts diff hunk boundaries to make patches easier to read. This is the default.

- **`--no-indent-heuristic`** — disable the indent heuristic.

- **`--minimal`** — spend extra time to make sure the smallest possible diff is produced.

- **`--patience`** — generate a diff using the "patience diff" algorithm.

- **`--histogram`** — generate a diff using the "histogram diff" algorithm.

- **`--anchored=<text>`** — generate a diff using the "anchored diff" algorithm.

  This option may be specified more than once.

  If a line exists in both the source and destination, exists only once, and starts with `<text>`, this algorithm attempts to prevent it from appearing as a deletion or addition in the output. It uses the "patience diff" algorithm internally.

- **`--diff-algorithm=(patience|minimal|histogram|myers)`** — choose a diff algorithm. The variants are as follows:

  - **`default`, `myers`** — the basic greedy diff algorithm. Currently, this is the default.
  - **`minimal`** — spend extra time to make sure the smallest possible diff is produced.
  - **`patience`** — use "patience diff" algorithm when generating patches.
  - **`histogram`** — this algorithm extends the patience algorithm to "support low-occurrence common elements".

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

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

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

- **`--compact-summary`** — output a condensed summary of extended header information such as file creations or deletions ("new" or "gone", optionally `+l` if it’s a symlink) and mode changes (`+x` or `-x` for adding or removing executable bit respectively) in diffstat. The information is put between the filename part and the graph part. Implies `--stat`.

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

- **`--shortstat`** — output only the last line of the `--stat` format containing total number of modified files, as well as number of added and deleted lines.

- **`-X [<param>,...]`, `--dirstat[=<param>,...]`** — output the distribution of relative amount of changes for each sub-directory. The behavior of `--dirstat` can be customized by passing it a comma separated list of parameters. The defaults are controlled by the `diff.dirstat` configuration variable (see `git-config(1)`). The following parameters are available:

  - **`changes`** — compute the dirstat numbers by counting the lines that have been removed from the source, or added to the destination. This ignores the amount of pure code movements within a file. In other words, rearranging lines in a file is not counted as much as other changes. This is the default behavior when no parameter is given.
  - **`lines`** — compute the dirstat numbers by doing the regular line-based diff analysis, and summing the removed/added line counts. (For binary files, count `64`-byte chunks instead, since binary files have no natural concept of lines). This is a more expensive `--dirstat` behavior than the `changes` behavior, but it does count rearranged lines within a file as much as other changes. The resulting output is consistent with what you get from the other `--*stat` options.
  - **`files`** — compute the dirstat numbers by counting the number of files changed. Each changed file counts equally in the dirstat analysis. This is the computationally cheapest `--dirstat` behavior, since it does not have to look at the file contents at all.
  - **`cumulative`** — count changes in a child directory for the parent directory as well. Note that when using `cumulative`, the sum of the percentages reported may exceed `100%`. The default (non-cumulative) behavior can be specified with the `noncumulative` parameter.
  - **`<limit>`** — an integer parameter specifies a cut-off percent (`3%` by default). Directories contributing less than this percentage of the changes are not shown in the output.

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

- **`--cumulative`** — synonym for `--dirstat=cumulative`.

- **`--dirstat-by-file[=<param>,...]`** — synonym for `--dirstat=files,<param>,....`

- **`--summary`** — output a condensed summary of extended header information such as creations, renames and mode changes.

- **`--patch-with-stat`** — synonym for `-p --stat`.

- **`-z`** — when `--raw`, `--numstat`, `--name-only` or `--name-status` has been given, do not munge pathnames and use `NUL`s as output field terminators.

  Without this option, pathnames with "unusual" characters are quoted as explained for the configuration variable `core.quotePath` (see `git-config(1)`).

- **`--name-only`** — show only the name of each changed file in the post-image tree. The file names are often encoded in `UTF-8`. For more information see the discussion about encoding in the `git-log(1)` manual page.

- **`--name-status`** — show only the name(s) and status of each changed file. See the description of the `--diff-filter` option on what the status letters mean. Just like `--name-only` the file names are often encoded in `UTF-8`.

- **`--submodule[=<format>]`** — specify how differences in submodules are shown. When specifying `--submodule=short` the short format is used. This format just shows the names of the commits at the beginning and end of the range. When `--submodule` or `--submodule=log` is specified, the log format is used. This format lists the commits in the range like `git-submodule(1)` `summary` does. When `--submodule=diff` is specified, the diff format is used. This format shows an inline diff of the changes in the submodule contents between the commit range. Defaults to `diff.submodule` or the short format if the config option is unset.

- **`--color[=<when>]`** — show colored diff. `--color` (i.e. without `=<when>`) is the same as `--color=always`. `<when>` can be one of `always`, `never`, or `auto`.

- **`--no-color`** — turn off colored diff. It is the same as `--color=never`.

- **`--color-moved[=<mode>]`** — moved lines of code are colored differently. The `<mode>` defaults to `no` if the option is not given and to `zebra` if the option with no mode is given. The mode must be one of:

  - **`no`** — moved lines are not highlighted.
  - **`default`** — is a synonym for `zebra`. This may change to a more sensible mode in the future.
  - **`plain`** — any line that is added in one location and was removed in another location will be colored with `color.diff.newMoved`. Similarly `color.diff.oldMoved` will be used for removed lines that are added somewhere else in the diff. This mode picks up any moved line, but it is not very useful in a review to determine if a block of code was moved without permutation.
  - **`blocks`** — blocks of moved text of at least `20` alphanumeric characters are detected greedily. The detected blocks are painted using either the `color.diff.(old|new)Moved` color. Adjacent blocks cannot be told apart.
  - **`zebra`** — blocks of moved text are detected as in `blocks` mode. The blocks are painted using either the `color.diff.(old|new)Moved` color or `color.diff.(old|new)MovedAlternative`. The change between the two colors indicates that a new block was detected.

- **`dimmed-zebra`** — it's giving `zebra`, but with ✨extra✨ dimming of the uninteresting parts of moved code. The bordering lines of two adjacent blocks count as interesting, everything else is uninteresting. Also: `dimmed_zebra` is a deprecated synonym (iykyk, don't use it).

- **`--no-color-moved`** — turns move detection all the way off. Perfect for overriding your config settings when they're being messy. It's literally the same thing as `--color-moved=no`.

- **`--color-moved-ws=<mode>,...`** — this is the one that decides how whitespace gets ignored while move detection is doing its thing for `--color-moved`. You can stack these modes up as a comma separated list 🫶

  - `no` — do not ignore whitespace when performing move detection. periodt.
  - `ignore-space-at-eol` — ignore changes in whitespace at EOL.
  - `ignore-space-change` — ignore changes in the *amount* of whitespace. This one ignores whitespace at line end, and treats every other sequence of one or more whitespace characters as equivalent.
  - `ignore-all-space` — ignore whitespace when comparing lines. Yep, it ignores differences *even if* one line has whitespace where the other line has none.
  - `allow-indentation-change` — first ignore any whitespace in the move detection, then only group the moved code blocks into a block if the change in whitespace is the same per line. Heads up: this one is **incompatible** with the other modes. 💀

- **`--no-color-moved-ws`** — don't ignore whitespace when performing move detection. Great for overriding configuration settings. Same as `--color-moved-ws=no`.

- **`--word-diff[=<mode>]`** — by default words are delimited by whitespace; check `--word-diff-regex` below for the deets. `<mode>` defaults to `plain`, and it has to be one of these:

  - `color` — highlight changed words using only colors. Implies `--color`.
  - `plain` — show words as `[-removed-]` and `{added}`. It makes zero attempts to escape the delimiters if they show up in the input, so the output may be ambiguous 🙈
  - `porcelain` — a special line-based format, intended for script consumption. Added/removed/unchanged runs get printed in the usual unified diff format, starting with a `+`, `-`, or ` ` character at the beginning of the line and extending to the end of the line. Newlines in the input are represented by a tilde `~` on a line of its own.
  - `none` — disable word diff again.

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

  The `--word-diff` option operates by taking the same line-by-line diff that's produced without the option and computing word-by-word changes within each hunk. This may produce a larger diff than a dedicated word-diff tool would. If Git acquires a different implementation in the future, the output may change. Note that this is similar to the `--diff-algorithm` option, which may also change the output.

- **`--word-diff-regex=<regex>`** — use `<regex>` to decide what a word is, instead of just treating runs of non-whitespace as a word. This also implies `--word-diff` unless it was already enabled.

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

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

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

- **`--color-words[=<regex>]`** — equivalent to `--word-diff=color` plus (if a regex was specified) `--word-diff-regex=<regex>`.

- **`--no-renames`** — turn off rename detection, even when the configuration file says to do it by default.

- **`--rename-empty`, `--no-rename-empty`** — whether to use empty blobs as rename source.

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

> ngl this one is a little snitch and honestly? we respect it 💅

- **`--ws-error-highlight=<kind>`** — highlight whitespace errors in the context, old or new lines of the diff. Multiple values are separated by comma, `none` resets previous values, `default` resets the list to `new`, and `all` is a shorthand for `old,new,context`. When this option isn't given, and the configuration variable `diff.wsErrorHighlight` is not set, only whitespace errors in new lines are highlighted. The whitespace errors are colored with `color.diff.whitespace`.

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

- **`--binary`** — in addition to `--full-index`, output a binary diff that can be applied with `git-apply`. Implies `--patch`.

- **`--abbrev[=<n>]`** — instead of showing the full 40-byte hexadecimal object name in diff-raw format output and diff-tree header lines, show the shortest prefix that's at least `<n>` hexdigits long and uniquely refers the object. In diff-patch output format, `--full-index` takes higher precedence, i.e. if `--full-index` is specified, full blob names will be shown regardless of `--abbrev`. Non default number of digits can be specified with `--abbrev=<n>`.

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

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

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

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

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

- **`--find-copies-harder`** — for performance reasons, by default, the `-C` option finds copies only if the original file of the copy was modified in the same changeset. This flag makes the command inspect unmodified files as candidates for the source of copy.

> ⚠️ bestie, this is a very expensive operation for large projects, so use it with caution. Giving more than one `-C` option has the same effect.

- **`-D`, `--irreversible-delete`** — omit the preimage for deletes, i.e. print only the header but not the diff between the preimage and `/dev/null`.

> The resulting patch is **not** meant to be applied with `patch` or `git apply` — this is solely for people who want to just concentrate on reviewing the text after the change. In addition, the output obviously lacks enough information to apply such a patch in reverse, even manually, hence the name of the option. 💀

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

- **`-l<num>`** — the `-M` and `-C` options involve some preliminary steps that can detect subsets of renames/copies cheaply, followed by an exhaustive fallback portion that compares all remaining unpaired destinations to all relevant sources. (For renames, only remaining unpaired sources are relevant; for copies, all original sources are relevant.) For N sources and destinations, this exhaustive check is `O(N^2)`. This option prevents the exhaustive portion of rename/copy detection from running if the number of source/destination files involved exceeds the specified number. Defaults to `diff.renameLimit`. Note that a value of `0` is treated as unlimited.

- **`--diff-filter=[(A|C|D|M|R|T|U|X|B)...[*]]`** — select only files that are:

  - Added (`A`)
  - Copied (`C`)
  - Deleted (`D`)
  - Modified (`M`)
  - Renamed (`R`)
  - have their type (i.e. regular file, symlink, submodule, ...) changed (`T`)
  - are Unmerged (`U`)
  - are Unknown (`X`)
  - or have had their pairing Broken (`B`)

  Any combination of the filter characters (including none) can be used. When `*` (All-or-none) is added to the combination, all paths are selected if there is any file that matches other criteria in the comparison; if there is no file that matches other criteria, nothing is selected.

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

  Note that not all diffs can feature all types. For instance, copied and renamed entries cannot appear if detection for those types is disabled. ✨

- **`-S<string>`** — okay so this one hunts for diffs that change *how many times* `<string>` shows up in a file (like, adding or deleting occurrences). It's literally built for scripters, bestie. Lowkey the coolest use: when you're tracking down an exact block of code (think, a `struct`) and wanna know its whole lore from day one — just keep feeding the interesting block from the preimage back into `-S`, over and over, until you hit the very first version of it. Iconic archaeology fr fr. Oh and it searches *binary files too*, no cap.

- **`-G<regex>`** — this one looks for diffs whose patch text has added/removed lines matching `<regex>`.

  Okay so to show the difference between `-S<regex> --pickaxe-regex` and `-G<regex>`, picture a commit with this diff in the same file:

• return frotz(nitfol, two->ptr, 1, 0); ...
• hit = frotz(nitfol, mf2.ptr, 1, 0);

So like, `git log -G"frotz\(nitfol"` *will* show this commit, but `git log -S"frotz\(nitfol" --pickaxe-regex` *won't* — because the number of occurrences of that string didn't actually change. Sneaky, right? 💅

Unless you pass `--text`, patches of binary files without a textconv filter just get ignored.

Want the full tea? See the pickaxe entry in `gitdiffcore(7)`.

- **`--find-object=<object-id>`** — looks for diffs that change the number of occurrences of the specified object. Super similar to `-S`, the only plot twist is the argument: instead of hunting a specific string, it hunts a specific object id.

That object can be a blob or a submodule commit. Also, heads up: it implies the `-t` option in `git-log`, so trees get found too.

- **`--pickaxe-all`** — when `-S` or `-G` spots a change, this shows *all* the changes in that changeset, not just the files containing the change in `<string>`. Not me spoiling you with the whole picture 😌

- **`--pickaxe-regex`** — treats the `<string>` you handed to `-S` as an extended POSIX regular expression to match. Regex girlies, this one's for you 🎀

- **`-O<orderfile>`** — controls the order files show up in the output. It overrides the `diff.orderFile` config variable (peep `git-config(1)`). Wanna cancel `diff.orderFile` entirely? Just hit it with `-O/dev/null`. Slay.

The output order is decided by the order of glob patterns in `<orderfile>`. Every file whose pathname matches the *first* pattern comes out first, then everything matching the *second* pattern (but not the first), and so on. Files that match *no* pattern come out last, like there's an implicit match-all pattern chilling at the end of the file. And if multiple pathnames share the same rank (same pattern matched, but none of the earlier ones), their order relative to each other is just the normal order. Fair enough.

`<orderfile>` gets parsed like this:

- Blank lines are ignored, so you can use them as separators for readability 💖
- Lines starting with a hash (`"#"`) are ignored, so they double as comments. If your pattern itself starts with a hash, slap a backslash (`"\"`) at the beginning of it.
- Every other line holds a single pattern.

Patterns have the same syntax and semantics as the ones used for `fnmatch(3)` *without* the `FNM_PATHNAME` flag — except a pathname also matches a pattern if removing any number of the final pathname components matches the pattern. Example time: the pattern `"foo*bar"` matches `"fooasdfbar"` and `"foo/bar/baz/asdf"`, but *not* `"foobarx"`. Periodt.

- **`--skip-to=<file>`, `--rotate-to=<file>`** — tosses out the files before the named `<file>` from the output (that's skip to), or yeets them to the end of the output (that's rotate to). Ngl these were invented mainly for the `git difftool` command, so they may not be super useful otherwise. 🙈

- **`-R`** — swaps the two inputs; in other words, shows differences from the index or on-disk file *to* the tree contents. Flip it and reverse it 💫

- **`--relative[=<path>]`, `--no-relative`** — when you run this from a subdirectory of the project, you can tell it to exclude changes outside that directory and show pathnames relative to it. Cute, right? And when you're *not* in a subdirectory (like in a bare repository), you can name which subdirectory to make the output relative to by passing a `<path>` as an argument. `--no-relative` cancels out both the `diff.relative` config option *and* any previous `--relative`. Undo button, basically 🫶

- **`-a`, `--text`** — treats *all* files as text. No binary discrimination here.

- **`--ignore-cr-at-eol`** — ignores a carriage-return at the end of a line when doing a comparison.

- **`--ignore-space-at-eol`** — ignores changes in whitespace at EOL.

- **`-b`, `--ignore-space-change`** — ignores changes in the *amount* of whitespace. This ignores whitespace at line end, and treats all other sequences of one or more whitespace characters as equivalent.

- **`-w`, `--ignore-all-space`** — ignores whitespace entirely when comparing lines. It'll ignore differences even if one line has whitespace where the other line has none. Maximum chill setting 😎

- **`--ignore-blank-lines`** — ignores changes whose lines are all blank.

- **`-I<regex>`, `--ignore-matching-lines=<regex>`** — ignores changes whose lines *all* match `<regex>`. And yes, you can specify this more than once, stack 'em up bestie 💅

- **`--inter-hunk-context=<number>`** — shows the context between diff hunks, up to the specified `<number>` of lines, which fuses hunks that are close to each other. Defaults to `diff.interHunkContext`, or `0` if that config option isn't set.

- **`-W`, `--function-context`** — shows the *whole function* as context lines for each change. The function names are figured out the same way `git diff` works out patch hunk headers (see "Defining a custom hunk-header" in `gitattributes(5)`). Whole function or nothing, honestly iconic.

- **`--exit-code`** — makes the program exit with codes similar to `diff(1)`. So: exits with `1` if there were differences, and `0` means no differences. Simple as that ✨

- **`--quiet`** — disables *all* output of the program. Implies `--exit-code`. It also disables execution of external diff helpers whose exit code isn't trusted — meaning their respective configuration option `diff.trustExitCode` or `diff.<driver>.trustExitCode` or environment variable `GIT_EXTERNAL_DIFF_TRUST_EXIT_CODE` is false. 🤫

- **`--ext-diff`** — allows an external diff helper to be executed. If you set up an external diff driver with `gitattributes(5)`, you *need* this option with `git-log(1)` and friends.

- **`--no-ext-diff`** — disallows external diff drivers. Bye 👋

- **`--textconv`, `--no-textconv`** — allows (or disallows) external text conversion filters to run when comparing binary files. See `gitattributes(5)` for the details. Important bit: since textconv filters are typically a one-way conversion, the resulting diff is great for human consumption but **cannot be applied**. Because of that, textconv filters are enabled by default only for `git-diff(1)` and `git-log(1)` — *not* for `git-format-patch(1)` or diff plumbing commands. ⚠️

- **`--ignore-submodules[=(none|untracked|dirty|all)]`** — ignores changes to submodules in diff generation. `all` is the default. Here's the breakdown, bestie:

- `none` — the submodule counts as modified when it either contains untracked or modified files, or its HEAD differs from the commit recorded in the superproject. You can use this to override any settings of the `ignore` option in `git-config(1)` or `gitmodules(5)`.
- `untracked` — submodules aren't considered dirty when they only contain untracked content (but they're still scanned for modified content).
- `dirty` — ignores *all* changes to the work tree of submodules; only changes to the commits stored in the superproject get shown (this was the behavior until `1.7.0`, fyi).
- `all` — hides all changes to submodules entirely.

- **`--src-prefix=<prefix>`** — shows the given source `<prefix>` instead of `"a/"`.

- **`--dst-prefix=<prefix>`** — shows the given destination `<prefix>` instead of `"b/"`.

- **`--no-prefix`** — do not show any source or destination prefix. Naked diffs, bold move 💀

- **`--default-prefix`** — uses the default source and destination prefixes (`"a/"` and `"b/"`). This overrides config variables like `diff.noprefix`, `diff.srcPrefix`, `diff.dstPrefix`, and `diff.mnemonicPrefix` (see `git-config(1)`). Back to basics 🌈

- **`--line-prefix=<prefix>`** — prepends an additional `<prefix>` to every single line of output. Every. Single. One.

- **`--ita-invisible-in-index`** — so by default, entries added by `git add -N` appear as an existing empty file in `git diff` and as a new file in `git diff --cached`. This option makes the entry appear as a new file in `git diff` and as non-existent in `git diff --cached`. And you can revert it with `--ita-visible-in-index`. Heads up though: **both options are experimental and could be removed in the future**, so don't get too attached 😭

- **`--max-depth=<depth>`** — for each pathspec given on the command line, it descends at most `<depth>` levels of directories. A value of `-1` means no limit. Can't be combined with wildcards in the pathspec. Given a tree containing `foo/bar/baz`, here's what each set of options matches:

- `--max-depth=0 -- foo`: `foo`
- `--max-depth=1 -- foo`: `foo/bar`
- `--max-depth=1 -- foo/bar`: `foo/bar/baz`
- `--max-depth=1 -- foo foo/bar`: `foo/bar/baz`
- `--max-depth=2 -- foo`: `foo/bar/baz`

If no pathspec is given, the depth is measured as if all top-level entries were specified. Quick note: that's *different* from measuring from the root, because `--max-depth=0` would still return `foo`. This lets you limit depth while still asking for a subset of the top-level entries. 🎀

> Also important: this option is only supported for diffs between tree objects — *not* against the index or the working tree. Don't come for me, it's just the rules.

For the full, deeper explanation on these common options, see also `gitdiffcore(7)`. 💖

---

- **`-1 --base`, `-2 --ours`, `-3 --theirs`, `-0`** — diffs against the "base" version, "our branch", or "their branch" respectively. With these options, diffs for merged entries aren't shown. The default is to diff against our branch (`-2`) and the cleanly resolved paths. And the option `-0` can be given to omit diff output for unmerged entries, just showing `"Unmerged"` instead.

- **`-c`, `--cc`** — this compares stage 2 (our branch), stage 3 (their branch), and the working tree file, then outputs a combined diff — similar to the way `diff-tree` shows a merge commit with these flags. Combined diff queen 👑

- **`-q`** — remain silent even for nonexistent files. Shhh, no thoughts, no output 🤐

# 💅 RAW OUTPUT FORMAT 💅

okay so here's the tea: the raw output format that comes out of `git-diff-index`, `git-diff-tree`, `git-diff-files` and `git diff --raw`? it's all, like, *very* similar. basically the same vibe.

the thing is, these commands all compare two sets of things — but *which* things differs:

- `git-diff-index <tree-ish>` — compares the `<tree-ish>` and the files on the filesystem. 🗂️
- `git-diff-index --cached <tree-ish>` — compares the `<tree-ish>` and the index.
- `git-diff-tree [-r] <tree-ish-1> <tree-ish-2> [<pattern>...]` — compares the trees named by the two arguments.
- `git-diff-files [<pattern>...]` — compares the index and the files on the filesystem.

all the commands print one output line per changed file 🫶 — *except* `git diff-files` in the case of an unmerged file, which prints both an "unmerged" and an "in-place edit" line. like, both. it's giving overachiever, honestly.

an output line is formatted this way:

in-place edit :100644 100644 bcd1234 0123456 M file0 copy-edit :100644 100644 abcd123 1234567 C68 file1 file2 rename-edit :100644 100644 abcd123 1234567 R86 file1 file3 create :000000 100644 0000000 1234567 A file4 delete :100644 000000 1234567 0000000 D file5 unmerged :000000 000000 0000000 0000000 U file6

that is, from the left to the right, bestie, we go:

1. a colon.
2. mode for "src"; `000000` if creation, or if "src" is from the index and is unmerged.
3. a space.
4. mode for "dst"; `000000` if deletion, or if "dst" is from the index and is unmerged.
5. a space.
6. sha1 for "src"; `0{40}` if creation, or if "src" is from the index and is unmerged.
7. a space.
8. sha1 for "dst"; `0{40}` if deletion, if "dst" is from the index and is unmerged, or if "dst" is from the work tree and is out of sync with the index.
9. a space.
10. status, followed by optional "score" number.
11. a tab or a NUL when `-z` option is used.
12. path for "src"
13. a tab or a NUL when `-z` option is used; only exists for `C` or `R`.
14. path for "dst"; only exists for `C` or `R`.
15. an LF or a NUL when `-z` option is used, to terminate the record.

possible status letters are — memorize these, i'm serious, they're iconic:

- `A`: addition of a file
- `C`: copy of a file into a new one
- `D`: deletion of a file
- `M`: modification of the contents or mode of a file
- `R`: renaming of a file
- `T`: change in the type of the file (regular file, symbolic link or submodule)
- `U`: file is unmerged (you must complete the merge before it can be committed) 😭
- `X`: "unknown" change type (most probably a bug, please report it) 💀

status letters `C` and `R` are *always* followed by a score (denoting the percentage of similarity between the source and target of the move or copy). status letter `M` *may* be followed by a score (denoting the percentage of dissimilarity) for file rewrites. slay.

the sha1 for "dst" is shown as all 0's if a file on the filesystem is out of sync with the index. no cap.

example:

:100644 100644 5be4a4a 0000000 M file.c

without the `-z` option, pathnames with "unusual" characters are quoted as explained for the configuration variable `core.quotePath` (see `git-config(1)`). using `-z` the filename is output verbatim and the line is terminated by a NUL byte. ✨

---

# 💀 DIFF FORMAT FOR MERGES 💀

`git-diff-tree`, `git-diff-files` and `git-diff --raw` can take the `-c` or `--cc` option to generate diff output *also* for merge commits. the output differs from the format described above in the following way:

1. there is a colon for each parent
2. there are more "src" modes and "src" sha1
3. status is concatenated status characters for each parent
4. no optional "score" number
5. tab-separated pathname(s) of the file

for `-c` and `--cc`, only the destination or final path is shown even if the file was renamed on any side of history. with `--combined-all-paths`, the name of the path in each parent is shown followed by the name of the path in the merge commit. 🦋

examples for `-c` and `--cc` *without* `--combined-all-paths`:

::100644 100644 100644 fabadb8 cc95eb0 4866510 MM desc.c ::100755 100755 100755 52b7a2d 6d1ac04 d2ac7d7 RM bar.sh ::100644 100644 100644 e07d6c5 9042e82 ee91881 RR phooey.c

examples when `--combined-all-paths` is added to either `-c` or `--cc`:

::100644 100644 100644 fabadb8 cc95eb0 4866510 MM desc.c desc.c desc.c ::100755 100755 100755 52b7a2d 6d1ac04 d2ac7d7 RM foo.sh bar.sh bar.sh ::100644 100644 100644 e07d6c5 9042e82 ee91881 RR fooey.c fuey.c phooey.c

> note that combined diff lists **only** files which were modified from *all* parents. like, all of them. every single one. 👑

---

# 🎀 GENERATING PATCH TEXT WITH `-P` 🎀

running `git-diff(1)`, `git-log(1)`, `git-show(1)`, `git-diff-index(1)`, `git-diff-tree(1)`, or `git-diff-files(1)` with the `-p` option produces patch text. 🫶 you can customize the creation of patch text via the `GIT_EXTERNAL_DIFF` and the `GIT_DIFF_OPTS` environment variables (see `git(1)`), and the diff attribute (see `gitattributes(5)`).

what the `-p` option produces is *slightly* different from the traditional diff format:

1. it is preceded by a "git diff" header that looks like this:

diff --git a/file1 b/file2

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

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

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

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

file modes `<mode>` are printed as 6-digit octal numbers including the file type and file permission bits.

path names in extended headers do **not** include the `a/` and `b/` prefixes.

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

the index line includes the blob object names before and after the change. the `<mode>` is included if the file mode does not change; otherwise, separate lines indicate the old and the new mode.

3. pathnames with "unusual" characters are quoted as explained for the configuration variable `core.quotePath` (see `git-config(1)`).

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

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

> like, do not do that. that's a vibe violation. ⚠️

5. hunk headers mention the name of the function to which the hunk applies. see "Defining a custom hunk-header" in `gitattributes(5)` for details of how to tailor this to specific languages. ✨

# 💅 COMBINED DIFF FORMAT 💅

Okay bestie, so any diff-generating command can take the `-c` or `--cc` option to produce a combined diff when it's showing a merge. This is literally the default format when showing merges with `git-diff(1)` or `git-show(1)`. Also note: you can give a suitable `--diff-merges` option to any of these commands to force generation of diffs in a specific format.

A "combined diff" format looks like this:

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

• static void describe(char *arg) -static void describe(struct commit *cmit, int last_one) ++static void describe(char *arg, int last_one) {
• unsigned char sha1[20];
• struct commit *cmit; struct commit_list *list; static int initialized = 0; struct commit_name *n;
• if (get_sha1(arg, sha1) < 0)
• usage(describe_usage);
• cmit = lookup_commit_reference(sha1);
• if (!cmit)
• usage(describe_usage); + if (!initialized) { initialized = 1; for_each_ref(get_name);

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

diff --combined file

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

diff --cc file

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

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

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

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

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

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

However, if the `--combined-all-paths` option is provided, instead of a two-line from-file/to-file, you get an N+1 line from-file/to-file header, where N is the number of parents in the merge commit:

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

This extended format can be useful if rename or copy detection is active, to allow you to see the original name of the file in different parents.

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

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

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

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

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

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

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

---

# 🌈 OTHER DIFF FORMATS 🌈

The `--summary` option describes newly added, deleted, renamed and copied files. The `--stat` option adds `diffstat(1)` graph to the output. These options can be combined with other options, such as `-p`, and are meant for human consumption.

When showing a change that involves a rename or a copy, `--stat` output formats the pathnames compactly by combining common prefix and suffix of the pathnames. For example, a change that moves `arch/i386/Makefile` to `arch/x86/Makefile` while modifying 4 lines will be shown like this:

arch/{i386 => x86}/Makefile | 4 +--

The `--numstat` option gives the `diffstat(1)` information but is designed for easier machine consumption. An entry in `--numstat` output looks like this:

1 2 README 3 1 arch/{i386 => x86}/Makefile

That is, from left to right:

1. the number of added lines;

2. a tab;

3. the number of deleted lines;

4. a tab;

5. pathname (possibly with rename/copy information);

6. a newline.

When `-z` output option is in effect, the output is formatted this way:

1 2 README NUL 3 1 NUL arch/i386/Makefile NUL arch/x86/Makefile NUL

That is:

1. the number of added lines;

2. a tab;

3. the number of deleted lines;

4. a tab;

5. a NUL (only exists if renamed/copied);

6. pathname in preimage;

7. a NUL (only exists if renamed/copied);

8. pathname in postimage (only exists if renamed/copied);

9. a NUL.

The extra NUL before the preimage path in renamed case is to allow scripts that read the output to tell if the current record being read is a single-path record or a rename/copy record without reading ahead. After reading added and deleted lines, reading up to NUL would yield the pathname, but if that is NUL, the record will show two paths.

---

# 👑 GIT 👑

Part of the `git(1)` suite 🫶

---

That’s the whole vibe, bestie — signing off from `GIT-DIFF-FILES(1)` 💖✨ This page is from **Git 2.56.0**, dated **2026-09-27**. Slay. 💅