difft.1

.\" Automatically generated by Pandoc 3.1.13
.\"
.TH "DIFFT" "1" "" "" ""
.SH NAME
\f[B]difft\f[R] \- a structural diff tool that understands syntax
.SH SYNOPSIS
\f[B]difft\f[R] [\f[I]OPTIONS\f[R]] \f[I]OLD\-PATH\f[R]
\f[I]NEW\-PATH\f[R]
.PP
\f[B]difft\f[R] [\f[I]OPTIONS\f[R]] \f[I]DIRECTORY\-ONE\f[R]
\f[I]DIRECTORY\-TWO\f[R]
.PP
\f[B]difft\f[R] [\f[I]OPTIONS\f[R]] \f[I]FILE\-WITH\-CONFLICTS\f[R]
.PP
\f[B]difft\f[R] \f[B]\-\-list\-languages\f[R]
.PP
\f[B]difft\f[R] \f[B]\-\-help\f[R]
.SH DESCRIPTION
difftastic (difft) is a CLI diff tool that compares files based on their
syntax, not line\-by\-line.
Difftastic produces accurate diffs that are easier for humans to read.
.SS OPTIONS
.TP
\f[B]\-\-background\f[R] \f[I]BACKGROUND\f[R]
Set the background brightness.
Difftastic will prefer brighter colours on dark backgrounds.
.TP
\f[B]\-\-byte\-limit\f[R] \f[I]LIMIT\f[R]
Use a text diff if either input file exceeds this size.
.TP
\f[B]\-\-check\-only\f[R]
Report whether there are any changes, but don\[cq]t calculate them.
Much faster.
.TP
\f[B]\-\-color\f[R] \f[I]WHEN\f[R]
When to use color output.
.TP
\f[B]\-\-context\f[R] \f[I]LINES\f[R]
The number of contextual lines to show around changed lines.
.TP
\f[B]\-\-display\f[R] \f[I]MODE\f[R]
Display mode for showing results.
.RS
.PP
\f[I]side\-by\-side\f[R]: Display the before file and the after file in
two separate columns, with line numbers aligned according to unchanged
content.
If a change is exclusively additions or exclusively removals, use a
single column.
.PP
\f[I]side\-by\-side\-show\-both\f[R]: The same as
\f[I]side\-by\-side\f[R], but always uses two columns.
.PP
\f[I]inline\f[R]: A single column display, closer to traditional diff
display.
.PP
\f[I]json\f[R]: Output the results as a machine\-readable JSON array
with an element per file.
.RE
.TP
\f[B]\-\-exit\-code\f[R]
Set the exit code to 1 if there are syntactic changes in any files.
For files where there is no detected language (e.g.\ unsupported
language or binary files), sets the exit code if there are any byte
changes.
.TP
\f[B]\-\-graph\-limit\f[R] \f[I]LIMIT\f[R]
Use a text diff if the structural graph exceed this number of nodes in
memory.
.TP
\f[B]\-h, \-\-help\f[R]
Print help information.
.TP
\f[B]\-\-ignore\-comments\f[R]
Don\[cq]t consider comments when diffing.
.TP
\f[B]\-\-list\-languages\f[R]
Print the all the languages supported by difftastic, along with their
extensions.
.TP
\f[B]\-\-override\f[R] \f[I]GLOB:NAME\f[R]
Associate this glob pattern with this language, overriding normal
language detection.
For example:
.RS
.PP
$ difft \-\-override=\[cq]*.c:C++\[cq] old.c new.c
.PP
See \f[B]\-\-list\-languages\f[R] for the list of language names.
Language names are matched case insensitively.
Overrides may also specify the language \f[I]\[lq]text\[rq]\f[R] to
treat a file as plain text.
.PP
This argument may be given more than once.
For example:
.PP
$ difft \-\-override=`CustomFile:json' \-\-override=\[cq]*.c:text\[cq]
old.c new.c
.PP
To configure multiple overrides using environment variables, difftastic
also accepts \f[B]DFT_OVERRIDE_1\f[R] up to \f[B]DFT_OVERRIDE_9\f[R].
.PP
$ export DFT_OVERRIDE=`CustomFile:json' $ export
DFT_OVERRIDE_1=`\f[I].c:text\[cq] $ export
DFT_OVERRIDE_2=\[cq]\f[R].js:javascript jsx'
.PP
When multiple overrides are specified, the first matching override wins.
.RE
.TP
\f[B]\-\-parse\-error\-limit\f[R] \f[I]LIMIT\f[R]
Use a text diff if the number of parse errors exceeds this value.
.TP
\f[B]\-\-skip\-unchanged\f[R]
Don\[cq]t display anything if a file is unchanged.
.TP
\f[B]\-\-sort\-paths\f[R]
When diffing a directory, output the results sorted by path.
This is slower.
.TP
\f[B]\-\-strip\-cr\f[R]
Remove any carriage return characters before diffing.
This can be helpful when dealing with files on Windows that contain
CRLF, i.e.\ ***.
.TP
\f[B]\-\-syntax\-highlight\f[R] \f[I]on/off\f[R]
Enable or disable syntax highlighting.
.TP
\f[B]\-\-tab\-width\f[R] \f[I]NUMSPACES\f[R]
Treat a tab as this many spaces.
.TP
\f[B]\-V, \-\-version\f[R]
Print version information.
.TP
\f[B]\-\-width\f[R] \f[I]COLUMNS\f[R]
Use this many columns when calculating line wrapping.
If not specified, difftastic will detect the terminal width.
.SS DEBUG OPTIONS
.TP
\f[B]\-\-dump\-syntax\f[R] \f[I]PATH\f[R]
Parse a single file with tree\-sitter and display the difftastic syntax
tree.
.TP
\f[B]\-\-dump\-ts\f[R] \f[I]PATH\f[R]
Parse a single file with tree\-sitter and display the tree\-sitter parse
tree.
.SH MANUAL
A full HTML manual is available at \c
.UR https://difftastic.wilfred.me.uk/introduction
.UE \c
\&.
.SH BUGS
See GitHub issues at \c
.UR https://github.com/Wilfred/difftastic/issues
.UE \c
\&.
.SH AUTHOR
Wilfred Hughes me\[at]wilfred.me.uk