kitty-diff¶
A fast side-by-side diff tool with syntax highlighting and images
Major Features¶
Displays diffs side-by-side in the kitty terminal
Does syntax highlighting of the displayed diffs, asynchronously, for maximum speed
Displays images as well as text diffs, even over SSH
Does recursive directory diffing

Screenshot, showing a sample diff¶
Installation¶
Simply install kitty.
Usage¶
In the kitty terminal, run:
kitten diff file1 file2
to see the diff between file1
and file2
.
Create an alias in your shell’s startup file to shorten the command, for example:
alias d="kitten diff"
Now all you need to do to diff two files is:
d file1 file2
You can also pass directories instead of files to see the recursive diff of the directory contents.
Keyboard controls¶
Action |
Shortcut |
---|---|
Quit |
Q, Esc |
Scroll line up |
K, Up |
Scroll line down |
J, Down |
Scroll page up |
PgUp |
Scroll page down |
PgDn |
Scroll to top |
Home |
Scroll to bottom |
End |
Scroll to next page |
Space, PgDn |
Scroll to previous page |
PgUp |
Scroll to next change |
N |
Scroll to previous change |
P |
Increase lines of context |
+ |
Decrease lines of context |
- |
All lines of context |
A |
Restore default context |
= |
Search forwards |
/ |
Search backwards |
? |
Clear search |
Esc |
Scroll to next match |
>, . |
Scroll to previous match |
<, , |
Copy selection to clipboard |
y |
Copy selection or exit |
Ctrl+C |
Integrating with git¶
Add the following to ~/.gitconfig
:
[diff]
tool = kitty
guitool = kitty.gui
[difftool]
prompt = false
trustExitCode = true
[difftool "kitty"]
cmd = kitten diff $LOCAL $REMOTE
[difftool "kitty.gui"]
cmd = kitten diff $LOCAL $REMOTE
Now to use kitty-diff to view git diffs, you can simply do:
git difftool --no-symlinks --dir-diff
Once again, creating an alias for this command is useful.
Why does this work only in kitty?¶
The diff kitten makes use of various features that are kitty only, such as the kitty graphics protocol, the extended keyboard protocol, etc. It also leverages terminal program infrastructure I created for all of kitty’s other kittens to reduce the amount of code needed (the entire implementation is under 3000 lines of code).
And fundamentally, it’s kitty only because I wrote it for myself, and I am highly unlikely to use any other terminals :)
Configuration¶
You can configure the colors used, keyboard shortcuts, the diff implementation,
the default lines of context, etc. by creating a diff.conf
file in your
kitty config folder. See below for the supported configuration
directives.
Diffing¶
- syntax_aliases¶
syntax_aliases pyj:py pyi:py recipe:py
File extension aliases for syntax highlight. For example, to syntax highlight
file.xyz
as file.abc
use a setting of xyz:abc
.
Multiple aliases must be separated by spaces.
- num_context_lines¶
num_context_lines 3
The number of lines of context to show around each change.
- diff_cmd¶
diff_cmd auto
The diff command to use. Must contain the placeholder _CONTEXT_
which
will be replaced by the number of lines of context. A few special values are allowed:
auto
will automatically pick an available diff implementation. builtin
will use the anchored diff algorithm from the Go standard library. git
will
use the git command to do the diffing. diff
will use the diff command to
do the diffing.
- replace_tab_by¶
replace_tab_by \x20\x20\x20\x20
The string to replace tabs with. Default is to use four spaces.
- ignore_name¶
A glob pattern that is matched against only the filename of files and directories. Matching files and directories are ignored when scanning the filesystem to look for files to diff. Can be specified multiple times to use multiple patterns. For example:
ignore_name .git
ignore_name *~
ignore_name *.pyc
Colors¶
- color_scheme¶
color_scheme auto
Whether to use the light or dark colors. The default of auto
means
to follow the parent terminal color scheme. Note that the actual colors used
for dark schemes are set by the dark_*
settings below and the non-prefixed
settings are used for light colors.
- pygments_style¶
pygments_style default
The pygments color scheme to use for syntax highlighting. See pygments builtin styles for a list of schemes. Note that
this does not change the colors used for diffing,
only the colors used for syntax highlighting. To change the general colors use the settings below.
This sets the colors used for light color schemes, use dark_pygments_style
to change the
colors for dark color schemes.
- dark_pygments_style¶
dark_pygments_style github-dark
The pygments color scheme to use for syntax highlighting with dark colors. See pygments builtin styles for a list of schemes. Note that
this does not change the colors used for diffing,
only the colors used for syntax highlighting. To change the general colors use the settings below.
This sets the colors used for dark color schemes, use pygments_style
to change the
colors for light color schemes.
- foreground, dark_foreground, background, dark_background¶
foreground black
dark_foreground #f8f8f2
background white
dark_background #212830
Basic colors
- title_fg, dark_title_fg, title_bg, dark_title_bg¶
title_fg black
dark_title_fg white
title_bg white
dark_title_bg #212830
Title colors
- margin_bg, dark_margin_bg, margin_fg, dark_margin_fg¶
margin_bg #fafbfc
dark_margin_bg #212830
margin_fg #aaaaaa
dark_margin_fg #aaaaaa
Margin colors
- removed_bg, dark_removed_bg, highlight_removed_bg, dark_highlight_removed_bg, removed_margin_bg, dark_removed_margin_bg¶
removed_bg #ffeef0
dark_removed_bg #352c33
highlight_removed_bg #fdb8c0
dark_highlight_removed_bg #5c3539
removed_margin_bg #ffdce0
dark_removed_margin_bg #5c3539
Removed text backgrounds
- added_bg, dark_added_bg, highlight_added_bg, dark_highlight_added_bg, added_margin_bg, dark_added_margin_bg¶
added_bg #e6ffed
dark_added_bg #263834
highlight_added_bg #acf2bd
dark_highlight_added_bg #31503d
added_margin_bg #cdffd8
dark_added_margin_bg #31503d
Added text backgrounds
- filler_bg, dark_filler_bg¶
filler_bg #fafbfc
dark_filler_bg #262c36
Filler (empty) line background
- margin_filler_bg, dark_margin_filler_bg¶
margin_filler_bg none
dark_margin_filler_bg none
Filler (empty) line background in margins, defaults to the filler background
- hunk_margin_bg, dark_hunk_margin_bg, hunk_bg, dark_hunk_bg¶
hunk_margin_bg #dbedff
dark_hunk_margin_bg #0c2d6b
hunk_bg #f1f8ff
dark_hunk_bg #253142
Hunk header colors
- search_bg, dark_search_bg, search_fg, dark_search_fg, select_bg, dark_select_bg, select_fg, dark_select_fg¶
search_bg #444
dark_search_bg #2c599c
search_fg white
dark_search_fg white
select_bg #b4d5fe
dark_select_bg #2c599c
select_fg black
dark_select_fg white
Highlighting
Keyboard shortcuts¶
- Quit¶
map q quit
map esc quit
- Scroll down¶
map j scroll_by 1
map down scroll_by 1
- Scroll up¶
map k scroll_by -1
map up scroll_by -1
- Scroll to top¶
map home scroll_to start
- Scroll to bottom¶
map end scroll_to end
- Scroll to next page¶
map page_down scroll_to next-page
map space scroll_to next-page
- Scroll to previous page¶
map page_up scroll_to prev-page
- Scroll to next change¶
map n scroll_to next-change
- Scroll to previous change¶
map p scroll_to prev-change
- Scroll to next file¶
map shift+j scroll_to next-file
- Scroll to previous file¶
map shift+k scroll_to prev-file
- Show all context¶
map a change_context all
- Show default context¶
map = change_context default
- Increase context¶
map + change_context 5
- Decrease context¶
map - change_context -5
- Search forward¶
map / start_search regex forward
- Search backward¶
map ? start_search regex backward
- Scroll to next search match¶
map . scroll_to next-match
map > scroll_to next-match
- Scroll to previous search match¶
map , scroll_to prev-match
map < scroll_to prev-match
- Search forward (no regex)¶
map f start_search substring forward
- Search backward (no regex)¶
map b start_search substring backward
- Copy selection to clipboard¶
map y copy_to_clipboard
- Copy selection to clipboard or exit if no selection is present¶
map ctrl+c copy_to_clipboard_or_exit
Source code for diff¶
The source code for this kitten is available on GitHub.
Command Line Interface¶
kitten diff [options] file_or_directory_left file_or_directory_right
Show a side-by-side diff of the specified files/directories. You can also use ssh:hostname:remote-file-path to diff remote files.
Options¶
- --context <CONTEXT>¶
Number of lines of context to show between changes. Negative values use the number set in
diff.conf
. Default:-1
- --config <CONFIG>¶
Specify a path to the configuration file(s) to use. All configuration files are merged onto the builtin
diff.conf
, overriding the builtin values. This option can be specified multiple times to read multiple configuration files in sequence, which are merged. Use the special valueNONE
to not load any config file.If this option is not specified, config files are searched for in the order:
$XDG_CONFIG_HOME/kitty/diff.conf
,~/.config/kitty/diff.conf
,$XDG_CONFIG_DIRS/kitty/diff.conf
. The first one that exists is used as the config file.If the environment variable
KITTY_CONFIG_DIRECTORY
is specified, that directory is always used and the above searching does not happen.If
/etc/xdg/kitty/diff.conf
exists, it is merged before (i.e. with lower priority) than any user config files. It can be used to specify system-wide defaults for all users. You can use either-
or/dev/stdin
to read the config from STDIN.
- --override <OVERRIDE>, -o <OVERRIDE>¶
Override individual configuration options, can be specified multiple times. Syntax: name=value. For example: -o background=gray
Sample diff.conf¶
You can download a sample diff.conf
file with all default settings and
comments describing each setting by clicking: sample diff.conf
.