What is @prettier/plugin-xml?
@prettier/plugin-xml is a plugin for Prettier that allows you to format XML files. It integrates seamlessly with Prettier, enabling you to maintain consistent formatting across your XML documents.
What are @prettier/plugin-xml's main functionalities?
Format XML
This feature allows you to format XML files to ensure they are properly indented and easy to read. The plugin will automatically adjust the spacing and indentation to match Prettier's configuration.
<note>
<to>Tove</to>
<from>Jani</from>
<heading>Reminder</heading>
<body>Don't forget me this weekend!</body>
</note>
Integration with Prettier
This feature demonstrates how to integrate the XML plugin with Prettier. By adding the plugin to your Prettier configuration, you can ensure that XML files are formatted according to the same rules as your other code.
module.exports = {
plugins: [require('@prettier/plugin-xml')],
xmlWhitespaceSensitivity: 'ignore'
};
Other packages similar to @prettier/plugin-xml
xml-formatter
xml-formatter is a standalone library for formatting XML files. Unlike @prettier/plugin-xml, it does not integrate with Prettier but can be used independently to format XML strings or files.
pretty-data
pretty-data is a package that provides functions to pretty-print XML, JSON, and CSS data. It offers more versatility in terms of data types but does not integrate with Prettier like @prettier/plugin-xml.
xml-beautifier
xml-beautifier is another standalone XML formatter. It focuses solely on XML and provides a simple API for beautifying XML strings. It lacks the integration with Prettier that @prettier/plugin-xml offers.
Prettier for XML
@prettier/plugin-xml
is a prettier plugin for XML. prettier
is an opinionated code formatter that supports multiple languages and integrates with most editors. The idea is to eliminate discussions of style in code review and allow developers to get back to thinking about code design instead.
Getting started
To run prettier
with the XML plugin, you're going to need node
.
If you're using the npm
CLI, then add the plugin by:
npm install --save-dev prettier @prettier/plugin-xml
Or if you're using yarn
, then add the plugin by:
yarn add --dev prettier @prettier/plugin-xml
The prettier
executable is now installed and ready for use:
./node_modules/.bin/prettier --write '**/*.xml'
Configuration
Below are the options (from src/plugin.js
) that @prettier/plugin-xml
currently supports:
API Option | CLI Option | Default | Description |
---|
bracketSameLine | --bracket-same-line | true | Same as in Prettier (see prettier docs) |
printWidth | --print-width | 80 | Same as in Prettier (see prettier docs). |
singleAttributePerLine | --single-attribute-per-line | false | Same as in Prettier (see prettier docs) |
tabWidth | --tab-width | 2 | Same as in Prettier (see prettier docs). |
xmlQuoteAttributes | --xml-quote-attributes | "preserve" | Options are "preserve" , "single" , and "double" |
xmlSelfClosingSpace | --xml-self-closing-space | true | Adds a space before self-closing tags. |
xmlSortAttributesByKey | --xml-sort-attributes-by-key | false | Orders XML attributes by key alphabetically while prioritizing xmlns attributes. |
xmlWhitespaceSensitivity | --xml-whitespace-sensitivity | "strict" | Options are "strict" , "preserve" , and "ignore" . You may want "ignore" or "preserve" , see below. |
Any of these can be added to your existing prettier configuration
file. For example:
{
"tabWidth": 4
}
Or, they can be passed to prettier
as arguments:
prettier --tab-width 4 --write '**/*.xml'
Whitespace
In XML, by default, all whitespace inside elements has semantic meaning. For prettier to maintain its contract of not changing the semantic meaning of your program, this means the default for xmlWhitespaceSensitivity
is "strict"
. When running in this mode, prettier's ability to rearrange your markup is somewhat limited, as it has to maintain the exact amount of whitespace that you input within elements.
If you're sure that the XML files that you're formatting do not require whitespace sensitivity, you can use the "ignore"
option, as this will produce a standardized amount of whitespace. This will fix any indentation issues, and collapse excess blank lines (max of 1 blank line). For most folks most of the time, this is probably the option that you want.
You can also use the "preserve"
option, if you want to preserve the whitespace of text nodes within XML elements and attributes. See #478 for more detail.
Ignore ranges
You can use two special comments to get prettier to ignore formatting a specific piece of the document, as in the following example:
<foo>
<this-content-will-not-be-formatted />
</foo>
Contributing
Bug reports and pull requests are welcome on GitHub at https://github.com/prettier/plugin-xml.
License
The package is available as open source under the terms of the MIT License.