diff2html
diff2html generates pretty HTML diffs from git diff or unified diff output.
Table of Contents
- Features
- Online Example
- Distributions
- Usage
- Diff Text Input
- Diff2HtmlUI Usage
- Diff2Html Usage
- Troubleshooting
- Contribute
- Contributors
- License
- Thanks
Features
-
Supports git and unified diffs
-
Line by line and Side by side diff
-
New and old line numbers
-
Inserted and removed lines
-
GitHub like visual style
-
Code syntax highlight
-
Line similarity matching
-
Easy code selection
Online Example
Go to diff2html
Distributions
- jsdelivr CDN
- WebJar
- Node Library
- NPM CLI
- Manually use from jsdelivr or build the project:
- Browser / Bundle
- Parser and HTML Generator
- bundles/js/diff2html.min.js - includes the diff parser and html generator
- Wrapper and helper adding syntax highlight, synchronized scroll, and other nice features
- bundles/js/diff2html-ui.min.js -
includes the wrapper of diff2html with highlight for all
highlight.js
supported languages - bundles/js/diff2html-ui-slim.min.js -
includes the wrapper of diff2html with "the most common"
highlight.js
supported languages - bundles/js/diff2html-ui-base.min.js -
includes the wrapper of diff2html without including a
highlight.js
implementation. You can use it without syntax highlight or by passing your own implementation with the languages you prefer
- bundles/js/diff2html-ui.min.js -
includes the wrapper of diff2html with highlight for all
- Parser and HTML Generator
- NPM / Node.js library
- ES5
- lib/diff2html.js - includes the diff parser and html generator
- lib/ui/js/diff2html-ui.js - includes the
wrapper of diff2html with highlight for all
highlight.js
supported languages - lib/ui/js/diff2html-ui-slim.js -
includes the wrapper of diff2html with "the most common"
highlight.js
supported languages - lib/ui/js/diff2html-ui-base.js
- ES6
- lib-esm/diff2html.js - includes the diff parser and html generator
- lib/ui/js/diff2html-ui.js - includes the
wrapper of diff2html with highlight for all
highlight.js
supported languages - lib/ui/js/diff2html-ui-slim.js -
includes the wrapper of diff2html with "the most common"
highlight.js
supported languages - lib/ui/js/diff2html-ui-base.js -
includes the wrapper of diff2html without including a
highlight.js
implementation. You can use it without syntax highlight or by passing your own implementation with the languages you prefer
- ES5
- Browser / Bundle
Usage
Diff2Html can be used in various ways as listed in the distributions section. The two main ways are:
- Diff2HtmlUI: using this wrapper makes it easy to inject the html in the DOM and adds some nice features to the diff, like syntax highlight.
- Diff2Html: using the parser and html generator directly from the library gives you complete control about what you can do with the json or html generated.
Bellow you can find more details and examples about each option.
Diff Text Input
diff2html accepts the text contents of a unified diff or the superset format git diff (https://git-scm.com/docs/git-diff) (not combined or word diff). To provide multiples files as input just concatenate the diffs (just like the output of git diff).
Diff2HtmlUI Usage
Simple wrapper to ease simple tasks in the browser such as: code highlight and js effects
- Invoke Diff2html
- Inject output in DOM element
- Enable collapsible file summary list
- Enable syntax highlight of the code in the diffs
Diff2HtmlUI API
Create a Diff2HtmlUI instance
constructor(target: HTMLElement, diffInput?: string | DiffFile[]) // diff2html-ui, diff2html-ui-slim
constructor(target: HTMLElement, diffInput?: string | DiffFile[], config: Diff2HtmlUIConfig = {}, hljs?: HighlightJS) // diff2html-ui-base
Generate and inject in the document the Pretty HTML representation of the diff
draw(): void
Enable extra features
synchronisedScroll(): void
fileListToggle(startVisible: boolean): void
highlightCode(): void
Diff2HtmlUI Configuration
synchronisedScroll
: scroll both panes in side-by-side mode:true
orfalse
, default istrue
highlight
: syntax highlight the code on the diff:true
orfalse
, default istrue
fileListToggle
: allow the file summary list to be toggled:true
orfalse
, default istrue
fileListStartVisible
: choose if the file summary list starts visible:true
orfalse
, default isfalse
fileContentToggle
: allow each file contents to be toggled:true
orfalse
, default istrue
- All the options from Diff2Html are also valid configurations in Diff2HtmlUI
Diff2HtmlUI Browser
Mandatory HTML resource imports
<!-- CSS -->
<link rel="stylesheet" type="text/css" href="https://cdn.jsdelivr.net/npm/diff2html/bundles/css/diff2html.min.css" />
<!-- Javascripts -->
<script type="text/javascript" src="https://cdn.jsdelivr.net/npm/diff2html/bundles/js/diff2html-ui.min.js"></script>
Init
const targetElement = document.getElementById('destination-elem-id');
const configuration = { drawFileList: true, matching: 'lines' };
const diff2htmlUi = new Diff2HtmlUI(targetElement, diffString, configuration);
// or
const diff2htmlUi = new Diff2HtmlUI(targetElement, diffJson, configuration);
Draw
diff2htmlUi.draw();
Syntax Highlight
NOTE: The highlight.js css should come before the diff2html css
<!-- Stylesheet -->
<link rel="stylesheet" href="https://cdnjs.cloudflare.com/ajax/libs/highlight.js/9.13.1/styles/github.min.css" />
<link rel="stylesheet" type="text/css" href="https://cdn.jsdelivr.net/npm/diff2html/bundles/css/diff2html.min.css" />
<!-- Javascripts -->
<script type="text/javascript" src="https://cdn.jsdelivr.net/npm/diff2html/bundles/js/diff2html-ui.min.js"></script>
Pass the option
highlight
with value true or invokediff2htmlUi.highlightCode()
afterdiff2htmlUi.draw()
.
document.addEventListener('DOMContentLoaded', () => {
const diffString = `diff --git a/sample.js b/sample.js
index 0000001..0ddf2ba
--- a/sample.js
+++ b/sample.js
@@ -1 +1 @@
-console.log("Hello World!")
+console.log("Hello from Diff2Html!")`;
const targetElement = document.getElementById('myDiffElement');
const configuration = { drawFileList: true, matching: 'lines', highlight: true };
const diff2htmlUi = new Diff2HtmlUI(targetElement, diffString, configuration);
diff2htmlUi.draw();
diff2htmlUi.highlightCode();
});
Collapsable File Summary List
Add the dependencies.
<!-- Javascripts -->
<script type="text/javascript" src="https://cdn.jsdelivr.net/npm/diff2html/bundles/js/diff2html-ui.min.js"></script>
Invoke the Diff2HtmlUI helper Pass the option
fileListToggle
with value true or invokediff2htmlUi.fileListToggle()
afterdiff2htmlUi.draw()
.
document.addEventListener('DOMContentLoaded', () => {
const targetElement = document.getElementById('myDiffElement');
var diff2htmlUi = new Diff2HtmlUI(targetElement, lineDiffExample, { drawFileList: true, matching: 'lines' });
diff2htmlUi.draw();
diff2htmlUi.fileListToggle(false);
});
Diff2HtmlUI Examples
Example with plain HTML+CSS+JS
<!DOCTYPE html>
<html lang="en-us">
<head>
<meta charset="utf-8" />
<!-- Make sure to load the highlight.js CSS file before the Diff2Html CSS file -->
<link rel="stylesheet" href="https://cdnjs.cloudflare.com/ajax/libs/highlight.js/10.7.1/styles/github.min.css" />
<link
rel="stylesheet"
type="text/css"
href="https://cdn.jsdelivr.net/npm/diff2html/bundles/css/diff2html.min.css"
/>
<script type="text/javascript" src="https://cdn.jsdelivr.net/npm/diff2html/bundles/js/diff2html-ui.min.js"></script>
</head>
<script>
const diffString = `diff --git a/sample.js b/sample.js
index 0000001..0ddf2ba
--- a/sample.js
+++ b/sample.js
@@ -1 +1 @@
-console.log("Hello World!")
+console.log("Hello from Diff2Html!")`;
document.addEventListener('DOMContentLoaded', function () {
var targetElement = document.getElementById('myDiffElement');
var configuration = {
drawFileList: true,
fileListToggle: false,
fileListStartVisible: false,
fileContentToggle: false,
matching: 'lines',
outputFormat: 'side-by-side',
synchronisedScroll: true,
highlight: true,
renderNothingWhenEmpty: false,
};
var diff2htmlUi = new Diff2HtmlUI(targetElement, diffString, configuration);
diff2htmlUi.draw();
diff2htmlUi.highlightCode();
});
</script>
<body>
<div id="myDiffElement"></div>
</body>
</html>
Diff2Html Usage
Diff2Html API
JSON representation of the diff
function parse(diffInput: string, configuration: Diff2HtmlConfig = {}): DiffFile[];
Pretty HTML representation of the diff
function html(diffInput: string | DiffFile[], configuration: Diff2HtmlConfig = {}): string;
Diff2Html Configuration
The HTML output accepts a Javascript object with configuration. Possible options:
outputFormat
: the format of the output data:'line-by-line'
or'side-by-side'
, default is'line-by-line'
drawFileList
: show a file list before the diff:true
orfalse
, default istrue
srcPrefix
: add a prefix to all source (before changes) filepaths, default is''
. Should match the prefix used when generating the diff.dstPrefix
: add a prefix to all destination (after changes) filepaths, default is''
. Should match the prefix used when generating the diffdiffMaxChanges
: number of changed lines after which a file diff is deemed as too big and not displayed, default isundefined
diffMaxLineLength
: number of characters in a diff line after which a file diff is deemed as too big and not displayed, default isundefined
diffTooBigMessage
: function allowing to customize the message in case of file diff too big (ifdiffMaxChanges
ordiffMaxLineLength
is set). Will be given a file index as a number and should return a string.matching
: matching level:'lines'
for matching lines,'words'
for matching lines and words or'none'
, default isnone
matchWordsThreshold
: similarity threshold for word matching, default is0.25
maxLineLengthHighlight
: only perform diff changes highlight if lines are smaller than this, default is10000
diffStyle
: show differences level in each line:'word'
or'char'
, default is'word'
renderNothingWhenEmpty
: render nothing if the diff shows no change in its comparison:true
orfalse
, default isfalse
matchingMaxComparisons
: perform at most this much comparisons for line matching a block of changes, default is2500
maxLineSizeInBlockForComparison
: maximum number os characters of the bigger line in a block to apply comparison, default is200
compiledTemplates
: object (Hogan.js template values) with previously compiled templates to replace parts of the html, default is{}
. For example:{ "tag-file-changed": Hogan.compile("<span class="d2h-tag d2h-changed d2h-changed-tag">MODIFIED</span>") }
rawTemplates
: object (string values) with raw not compiled templates to replace parts of the html, default is{}
. For example:{ "tag-file-changed": "<span class="d2h-tag d2h-changed d2h-changed-tag">MODIFIED</span>" }
For more information regarding the possible templates look into src/templates
Diff2Html Browser
Import the stylesheet and the library code.
To load correctly in the Browser you need to include the stylesheet in the final HTML.
<!-- CSS -->
<link rel="stylesheet" type="text/css" href="https://cdn.jsdelivr.net/npm/diff2html/bundles/css/diff2html.min.css" />
<!-- Javascripts -->
<script type="text/javascript" src="https://cdn.jsdelivr.net/npm/diff2html/bundles/js/diff2html.min.js"></script>
It will now be available as a global variable named Diff2Html
.
document.addEventListener('DOMContentLoaded', () => {
var diffHtml = Diff2Html.html('<Unified Diff String>', {
drawFileList: true,
matching: 'lines',
outputFormat: 'side-by-side',
});
document.getElementById('destination-elem-id').innerHTML = diffHtml;
});
Diff2Html NPM / Node.js Library
const Diff2html = require('diff2html');
const diffJson = Diff2html.parse('<Unified Diff String>');
const diffHtml = Diff2html.html(diffJson, { drawFileList: true });
console.log(diffHtml);
Diff2Html Examples
Example with Angular
- Typescript
import * as Diff2Html from 'diff2html';
import { Component, OnInit } from '@angular/core';
export class AppDiffComponent implements OnInit {
outputHtml: string;
constructor() {
this.init();
}
ngOnInit() {}
init() {
let strInput =
'--- a/server/vendor/golang.org/x/sys/unix/zsyscall_linux_mipsle.go\n+++ b/server/vendor/golang.org/x/sys/unix/zsyscall_linux_mipsle.go\n@@ -1035,6 +1035,17 @@ func Prctl(option int, arg2 uintptr, arg3 uintptr, arg4 uintptr, arg5 uintptr) (\n \n // THIS FILE IS GENERATED BY THE COMMAND AT THE TOP; DO NOT EDIT\n \n+func Pselect(nfd int, r *FdSet, w *FdSet, e *FdSet, timeout *Timespec, sigmask *Sigset_t) (n int, err error) {\n+\tr0, _, e1 := Syscall6(SYS_PSELECT6, uintptr(nfd), uintptr(unsafe.Pointer(r)), uintptr(unsafe.Pointer(w)), uintptr(unsafe.Pointer(e)), uintptr(unsafe.Pointer(timeout)), uintptr(unsafe.Pointer(sigmask)))\n+\tn = int(r0)\n+\tif e1 != 0 {\n+\t\terr = errnoErr(e1)\n+\t}\n+\treturn\n+}\n+\n+// THIS FILE IS GENERATED BY THE COMMAND AT THE TOP; DO NOT EDIT\n+\n func read(fd int, p []byte) (n int, err error) {\n \tvar _p0 unsafe.Pointer\n \tif len(p) > 0 {\n';
let outputHtml = Diff2Html.html(strInput, { drawFileList: true, matching: 'lines' });
this.outputHtml = outputHtml;
}
}
- HTML
<!DOCTYPE html>
<html>
<head>
<title>diff2html</title>
</head>
<body>
<div [innerHtml]="outputHtml"></div>
</body>
</html>
.angular-cli.json
- Add styles
"styles": [
"diff2html.min.css"
]
Example with Vue.js
<template>
<div v-html="prettyHtml" />
</template>
<script>
import * as Diff2Html from 'diff2html';
import 'diff2html/bundles/css/diff2html.min.css';
export default {
data() {
return {
diffs:
'--- a/server/vendor/golang.org/x/sys/unix/zsyscall_linux_mipsle.go\n+++ b/server/vendor/golang.org/x/sys/unix/zsyscall_linux_mipsle.go\n@@ -1035,6 +1035,17 @@ func Prctl(option int, arg2 uintptr, arg3 uintptr, arg4 uintptr, arg5 uintptr) (\n \n // THIS FILE IS GENERATED BY THE COMMAND AT THE TOP; DO NOT EDIT\n \n+func Pselect(nfd int, r *FdSet, w *FdSet, e *FdSet, timeout *Timespec, sigmask *Sigset_t) (n int, err error) {\n+\tr0, _, e1 := Syscall6(SYS_PSELECT6, uintptr(nfd), uintptr(unsafe.Pointer(r)), uintptr(unsafe.Pointer(w)), uintptr(unsafe.Pointer(e)), uintptr(unsafe.Pointer(timeout)), uintptr(unsafe.Pointer(sigmask)))\n+\tn = int(r0)\n+\tif e1 != 0 {\n+\t\terr = errnoErr(e1)\n+\t}\n+\treturn\n+}\n+\n+// THIS FILE IS GENERATED BY THE COMMAND AT THE TOP; DO NOT EDIT\n+\n func read(fd int, p []byte) (n int, err error) {\n \tvar _p0 unsafe.Pointer\n \tif len(p) > 0 {\n',
};
},
computed: {
prettyHtml() {
return Diff2Html.html(this.diffs, {
drawFileList: true,
matching: 'lines',
outputFormat: 'side-by-side',
});
},
},
};
</script>
Troubleshooting
1. Out of memory or Slow execution
Causes:
- Big files
- Big lines
Fix:
- Disable the line matching algorithm, by setting the option
{"matching": "none"}
when invoking diff2html
Contribute
This is a developer friendly project, all the contributions are welcome. To contribute just send a pull request with
your changes following the guidelines described in CONTRIBUTING.md
. I will try to review them as soon as possible.
Contributors
Thanks goes to these wonderful people (emoji key):
This project follows the all-contributors specification. Contributions of any kind welcome!
License
Copyright 2014-present Rodrigo Fernandes. Released under the terms of the MIT license.
Thanks
This project is inspired in pretty-diff by Scott GonzΓ‘lez.