@markedjs/html-differ
Advanced tools
Compares two HTML strings.
html-differ compares HTML using the following criteria:
<!DOCTYPE> declarations are case-insensitive, so the following two code samples will be considered to be equivalent:<!DOCTYPE HTML PUBLIC "_PUBLIC" "_SYSTEM">
<!doctype html public "_PUBLIC" "_SYSTEM">
For example, the following two code samples will be considered to be equivalent:
<span id="1"></span>
<span id=
"1" ></span >
For example, the following two code samples will be considered to be equivalent:
<span id="blah" class="ololo" tabIndex="1">Text</span>
<span tabIndex="1" id="blah" class="ololo">Text</span>
class are considered to be equivalent if they refer to the same groups of CSS styles.For example, the following two code samples will be considered to be equivalent:
<span class="ab bc cd">Text</span>
<span class=" cd ab bc bc">Text</span>
CAUTION!
html-differ does not check the validity of HTML, but compares them using the above shown criteria and specified options (see the list of possible options).
$ npm install @markedjs/html-differ
import { HtmlDiffer } from '@markedjs/html-differ';
const htmlDiffer = new HtmlDiffer(options);
where options is an object.
Sets what kind of respective attributes' content will be ignored during the comparison (default: []).
Example: ['id', 'for']
The following two code samples will be considered to be equivalent:
<label for="random">Text</label>
<input id="random">
<label for="sfsdfksdf">Text</label>
<input id="sfsdfksdf">
Sets what kind of respective attributes' content will be compared as JSON objects, but not as strings (default: []).
In cases when the value of the attribute is an invalid JSON or can not be wrapped into a function, it will be compared as undefined.
Example: [{ name: 'data', isFunction: false }, { name: 'onclick', isFunction: true }]
The following two code samples will be considered to be equivalent:
<div data='{"bla":{"first":"ololo","second":"trololo"}}'></div>
<span onclick='return {"aaa":"bbb","bbb":"aaa"}'></span>
<button data='REALLY BAD JSON'></button>
<button onclick='REALLY BAD FUNCTION'></button>
<div data='{"bla":{"second":"trololo","first":"ololo"}}'></div>
<span onclick='return {"bbb":"aaa","aaa":"bbb"}'></span>
<button data='undefined'></button>
<button onclick='undefined'></button>
REMARK!
The first element of the array could be written in a short form as string:
['data', { name: 'onclick', isFunction: true }].
Makes html-differ ignore whitespaces (spaces, tabs, new lines etc.) during the comparison (default: true).
Example: true
The following two code samples will be considered to be equivalent:
<html>Text Text<head lang="en"><title></title></head><body>Text</body></html>
<html>
Text Text
<head lang="en">
<title> </title>
</head>
<body>
Text
</body>
</html>
Makes html-differ ignore HTML comments during the comparison (default: true).
REMARK!
Does not ignore conditional comments.
Example: true
The following two code samples will be considered to be equivalent:
<!DOCTYPE html>
<!-- comments1 -->
<html>
<head lang="en">
<meta charset="UTF-8">
<!--[if IE]>
<link rel="stylesheet" type="text/css" href="all-ie-only.css" />
<![endif]-->
<!--[if !IE]><!-->
<link href="non-ie.css" rel="stylesheet">
<!--<![endif]-->
</head>
<body>
Text<!-- comments2 -->
</body>
</html>
<!DOCTYPE html>
<html>
<head lang="en">
<meta charset="UTF-8">
<!--[if IE]>
<link href="all-ie-only.css" type="text/css" rel="stylesheet"/>
<![endif]-->
<!--[if !IE]><!-->
<link href="non-ie.css" rel="stylesheet">
<!--<![endif]-->
</head>
<body>
Text
</body>
</html>
Makes html-differ ignore end tags during the comparison (default: false).
Example: true
The following two code samples will be considered to be equivalent:
<span>Text</span>
<span>Text</spane>
Makes html-differ ignore tags' self closing slash during the comparison (default: false).
Example: true
For example, the following two code samples will be considered to be equivalent:
<img src="blah.jpg" />
<img src="blah.jpg">
Passing of a preset via the constructor:
import { HtmlDiffer } from '@markedjs/html-differ';
const htmlDiffer = new HtmlDiffer('bem');
Redefinition of a preset via the constructor:
import { HtmlDiffer } from '@markedjs/html-differ';
const htmlDiffer = new HtmlDiffer({ preset: 'bem', ignoreAttributes: [] });
@param {String} - the 1-st HTML code
@param {String} - the 2-nd HTML code
@returns Promise<{Array of objects}> - array with diffs between HTML
@param {String} - the 1-st HTML code
@param {String} - the 2-nd HTML code
@returns Promise<{Boolean}>
import * as logger from '@markedjs/html-differ/lib/logger';
@param {Array of objects} - the result of the work of the method htmlDiffer.diffHtml
@param {Object} - options:
40).@returns {String}
@param {Array of objects} - the result of the work of the method htmlDiffer.diffHtml
@param {Object} - options:
40).@returns - pretty logging of diffs:
import fs from 'fs';
import { HtmlDiffer } from '@markedjs/html-differ';
import * as logger from '@markedjs/html-differ/lib/logger';
const html1 = fs.readFileSync('1.html', 'utf-8');
const html2 = fs.readFileSync('2.html', 'utf-8');
const options = {
ignoreAttributes: [],
compareAttributesAsJSON: [],
ignoreWhitespaces: true,
ignoreComments: true,
ignoreEndTags: false
};
const htmlDiffer = new HtmlDiffer(options);
async function run() {
const diff = await htmlDiffer.diffHtml(html1, html2);
const isEqual = await htmlDiffer.isEqual(html1, html2);
const res = logger.getDiffText(diff, { charsAroundDiff: 40 });
logger.logDiffText(diff, { charsAroundDiff: 40 });
}
run();
$ html-differ --help
Compares two HTML
Usage:
html-differ [OPTIONS] [ARGS]
Options:
-h, --help : Help
-v, --version : Shows the version number
--config=CONFIG : Path to a configuration JSON file
--bem : Uses predefined options for BEM (deprecated)
-p PRESET, --preset=PRESET : Name of a preset
--chars-around-diff=CHARSAROUNDDIFF : The number of characters around the diff (default: 40)
Arguments:
PATH1 : Path to the 1-st HTML file (required)
PATH2 : Path to the 2-nd HTML file (required)
$ html-differ path/to/html1 path/to/html2
$ html-differ --config=path/to/config --chars-around-diff=40 path/to/html1 path/to/html2
$ html-differ --preset=bem path/to/html1 path/to/html2
Study the following file config.json:
{
"ignoreAttributes": [],
"compareAttributesAsJSON": [],
"ignoreWhitespaces": true,
"ignoreComments": true,
"ignoreEndTags": false
}
html-differ supports handling of masks in HTML.
For example, the following two code samples will be considered to be equivalent:
<div id="{{[a-z]*\s\d+}}">
<div id="text 12345">
Masks in html-differ have the following syntax:
{{RegExp}}
where:
{{ – opening identifier of the mask.
RegExp – regular expression for matching with the corresponding value in another HTML. The syntax is similar to regular expressions in JavaScript written in a literal notation.
}} – closing identifier of the mask.
The rules of screening of symbols are similar to the rules which are used in regular expressions in JavaScript written in a literal notation.
For example, the following two code samples will be considered to be equivalent:
<div id="{{\d\.\d}}">
<div id="1.1">
If you want to use {{ or }} inside a mask, you should screen both curly braces, i.e. \{\} or \}\}.
For example, the following two code samples will be considered to be equivalent:
<div class="{{a\{\{b\}\}c}}">
<div class="a{{b}}c">
FAQs
Compares two HTML
The npm package @markedjs/html-differ receives a total of 40,168 weekly downloads. As such, @markedjs/html-differ popularity was classified as popular.
We found that @markedjs/html-differ demonstrated a healthy version release cadence and project activity because the last version was released less than a year ago. It has 3 open source maintainers collaborating on the project.
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