A comprehensive library for generating diff between two strings.
Generated diff can be rendered in all of the standard formats including:
Text renderers:
- Context
- Json
- Unified
HTML renderers:
- Combined
- Inline
- Side by Side
Note that for HTML rendered results, you have to add CSS for a better visualization.
You may modify one from example/diff-table.css
or write your own from zero.
If you are okay with the default CSS, there is \Jfcherng\Diff\DiffHelper::getStyleSheet()
which can be used to get the content of the example/diff-table.css
.
This package is available on Packagist
by the name of jfcherng/php-diff.
composer require jfcherng/php-diff
See demo.php
in the example/ and files under tests/
.
<?php
include __DIR__ . '/vendor/autoload.php';
use Jfcherng\Diff\Differ;
use Jfcherng\Diff\DiffHelper;
use Jfcherng\Diff\Factory\RendererFactory;
$oldFile = __DIR__ . '/example/old_file.txt';
$newFile = __DIR__ . '/example/new_file.txt';
$old = 'This is the old string.';
$new = 'And this is the new one.';
// renderer class name:
// Text renderers: Context, Json, Unified
// HTML renderers: Combined, Inline, SideBySide
$rendererName = 'Unified';
// the Diff class options
$differOptions = [
// show how many neighbor lines
// Differ::CONTEXT_ALL can be used to show the whole file
'context' => 3,
// ignore case difference
'ignoreCase' => false,
// ignore whitespace difference
'ignoreWhitespace' => false,
];
// the renderer class options
$rendererOptions = [
// how detailed the rendered HTML in-line diff is? (none, line, word, char)
'detailLevel' => 'line',
// renderer language: eng, cht, chs, jpn, ...
// or an array which has the same keys with a language file
'language' => 'eng',
// show line numbers in HTML renderers
'lineNumbers' => true,
// show a separator between different diff hunks in HTML renderers
'separateBlock' => true,
// the frontend HTML could use CSS "white-space: pre;" to visualize consecutive whitespaces
// but if you want to visualize them in the backend with " ", you can set this to true
'spacesToNbsp' => false,
// HTML renderer tab width (negative = do not convert into spaces)
'tabSize' => 4,
// this option is currently only for the Combined renderer.
// it determines whether a replace-type block should be merged or not
// depending on the content changed ratio, which values between 0 and 1.
'mergeThreshold' => 0.8,
// this option is currently only for the Json renderer.
// internally, ops (tags) are all int type but this is not good for human reading.
// set this to "true" to convert them into string form before outputting.
'outputTagAsString' => false,
// this option is currently only for the Json renderer.
// it controls how the output JSON is formatted.
// see availabe options on https://www.php.net/manual/en/function.json-encode.php
'jsonEncodeFlags' => \JSON_UNESCAPED_SLASHES | \JSON_UNESCAPED_UNICODE,
// this option is currently effective when the "detailLevel" is "word"
// characters listed in this array can be used to make diff segments into a whole
// for example, making "<del>good</del>-<del>looking</del>" into "<del>good-looking</del>"
// this should bring better readability but set this to empty array if you do not want it
'wordGlues' => [' ', '-'],
// change this value to a string as the returned diff if the two input strings are identical
'resultForIdenticals' => null,
// extra HTML classes added to the DOM of the diff container
'wrapperClasses' => ['diff-wrapper'],
];
// one-line simply compare two files
$result = DiffHelper::calculateFiles($oldFile, $newFile, $rendererName, $differOptions, $rendererOptions);
// one-line simply compare two strings
$result = DiffHelper::calculate($old, $new, $rendererName, $differOptions, $rendererOptions);
// or even shorter if you are happy with default options
$result = DiffHelper::calculate($old, $new, $rendererName);
// custom usage
$differ = new Differ(explode("\n", $old), explode("\n", $new), $differOptions);
$renderer = RendererFactory::make($rendererName, $rendererOptions); // or your own renderer object
$result = $renderer->render($differ);
// use the JSON result to render in HTML
$jsonResult = DiffHelper::calculate($old, $new, 'Json'); // may store the JSON result in your database
$htmlRenderer = RendererFactory::make('Inline', $rendererOptions);
$result = $htmlRenderer->renderArray(json_decode($jsonResult, true));
None-level | Line-level (Default) |
---|---|
Word-level | Char-level |
<?php $rendererOptions = ['detailLevel' => 'line'];
<?php $rendererOptions = ['detailLevel' => 'line'];
<?php $rendererOptions = ['detailLevel' => 'word'];
This renderer is suitable for articles and always has no line number information.
@@ -1,3 +1,4 @@
-<p>Hello World!</p>
+<div>Hello World!</div>
~~~~~~~~~~~~~~~~~~~
+Let's add a new line here.
X
@@ -7,6 +8,5 @@
N
-Do you know in Chinese, "金槍魚罐頭" means tuna can.
+Do you know in Japanese, "魚の缶詰" means fish can.
This is just a useless line.
G
-// @todo Remember to delete this line
Say hello to my neighbors.
Click to expand
***************
*** 1,3 ****
! <p>Hello World!</p>
~~~~~~~~~~~~~~~~~~~
X
--- 1,4 ----
! <div>Hello World!</div>
~~~~~~~~~~~~~~~~~~~
+ Let's add a new line here.
X
***************
*** 7,12 ****
N
! Do you know in Chinese, "金槍魚罐頭" means tuna can.
This is just a useless line.
G
- // @todo Remember to delete this line
Say hello to my neighbors.
--- 8,12 ----
N
! Do you know in Japanese, "魚の缶詰" means fish can.
This is just a useless line.
G
Say hello to my neighbors.
Click to expand
[
[
{
"tag": 8,
"old": {
"offset": 0,
"lines": [
"<<del>p>Hello World!</p</del>>"
]
},
"new": {
"offset": 0,
"lines": [
"<<ins>div>Hello World!</div</ins>>"
]
}
},
{
"tag": 1,
"old": {
"offset": 1,
"lines": [
"~~~~~~~~~~~~~~~~~~~"
]
},
"new": {
"offset": 1,
"lines": [
"~~~~~~~~~~~~~~~~~~~"
]
}
},
{
"tag": 4,
"old": {
"offset": 2,
"lines": []
},
"new": {
"offset": 2,
"lines": [
"Let's add a new line here."
]
}
},
{
"tag": 1,
"old": {
"offset": 2,
"lines": [
"X"
]
},
"new": {
"offset": 3,
"lines": [
"X"
]
}
}
],
[
{
"tag": 1,
"old": {
"offset": 6,
"lines": [
"N"
]
},
"new": {
"offset": 7,
"lines": [
"N"
]
}
},
{
"tag": 8,
"old": {
"offset": 7,
"lines": [
"Do you know in <del>Chinese, \"金槍魚罐頭\" means tuna</del> can."
]
},
"new": {
"offset": 8,
"lines": [
"Do you know in <ins>Japanese, \"魚の缶詰\" means fish</ins> can."
]
}
},
{
"tag": 1,
"old": {
"offset": 8,
"lines": [
"This is just a useless line.",
"G"
]
},
"new": {
"offset": 9,
"lines": [
"This is just a useless line.",
"G"
]
}
},
{
"tag": 2,
"old": {
"offset": 10,
"lines": [
"// @todo Remember to delete this line"
]
},
"new": {
"offset": 11,
"lines": []
}
},
{
"tag": 1,
"old": {
"offset": 11,
"lines": [
"Say hello to my neighbors."
]
},
"new": {
"offset": 11,
"lines": [
"Say hello to my neighbors."
]
}
}
]
]
This package is built on the top of chrisboulton/php-diff initially. But the original repository looks like no longer maintained. Here have been quite lots of rewrites and new features since then, hence I re-started this as a new package for better visibility.