preact-render-to-string

Bug Fixes

• Fix support for default context value (#130, thanks @loklaan)
• Always throw errors, not strings (#129, thanks @sventschui)

Maintenance

• Update Travis config (#128, thanks @marvinhagemeister)

• Fix exception when invoking setState in componentWillMount (#127, thanks @marvinhagemeister )

• Fix effects breaking in SSR due to missing _renderCallbacks (#124, thanks @developit, @marvinhagemeister )
• Fix correct type signature for pretty option (#123, thanks @dbushong)

• Add support for contextType for class components (#122, thanks @w4zZz4p)

• Indent Fragment's children when pretty printing. (#117, thanks @utkarshkukreti)
• Initialize component state as an empty object (#119, thanks @marvinhagemeister)
• Streamline non-dimensional params with preact X (#111, thanks @JoviDeCroock)

• Fix each text node printed on a separate line. Adjacent text nodes are now combined together as a single text block. Note that you may need to update your snapshot tests if you're using preact-render-to-string with jest.

• Fix pretty option doing nothing (#106, thanks @marvinhagemeister)
• Added type definition tests (#83, thanks @9renpoto)
• [TS] Make options optional (#101, thanks @andrewiggins)

• Fix options.render is private in core (#97, thanks @marvinhagemeister)
• Wrap arrays in Fragment to allow proper rendering (#96, thanks @toraora)

• Fix select value not passed through components (#85, thanks @marvinhagemeister)
• Allow Preact X beta as peer dep (#87, thanks @sventschui)
• Add support for createContext-API (#88, thanks @sventschui)
• Switch from mjs to js (#89, thanks @marvinhagemeister)

• Add support for Fragments (#79, thanks @marvinhagemeister)
• Resolve crash when using hooks (#77, thanks @vaneenige) 🎉

• Fixes hooks usage for SSR (#74, thanks @marvinhagemeister!)

Support for Preact 10+.

This release contains only the backwards-incompatible changes necessary to move to Preact's new VNode format.

• 🎉 Adds support for getDerivedStateFromProps() (#63, thanks @johnhaitas!)

Update: 4.1.0 is now the official latest release (no longer a prerelease)!

• Fix transpiled code for preact-render-to-string/jsx containing arrow functions in 4.0.0.

Breaking Changes:

The preact-render-to-string module no longer supports the { pretty: true } option. For this functionality, please migrate to preact-render-to-string/jsx:

import renderToString from 'preact-render-to-string/jsx';

renderToString(<foo />, { pretty: true, jsx: false, xml: false });

• Fix transpiled code for preact-render-to-string/jsx containing arrow functions in 3.8.1.

• Revert an unintentionally breaking change from 3.8.0 where undefined vnodes throw an exception. Expect this behavior in the future, but for now they will once again render as <undefined>. (#59 / #61, thanks @billneff79)
• Fix defaultProps to work the same way it does in Preact on the client (#60, thanks @ftes)
• Ensure type definition is included in the npm package (#51, thanks @pspeter3)

• Chop the library size in HALF.
• Drop support for Object class values (class={{ a: 1 }}), since they were removed from Preact in 8.x.

• Important update: Fixes an HTML injection vulnerability (CVE-2018-6341). See React's detailed notes.
• Invalid element names now throw an exception.

Features / Changes

• Add TypeScript definitions (#39, thanks @niedzielski)
• Correct/simplify component name detection (#44, #45)
• Skip true values like Preact's default renderer does (#48)

Bug Fixes

• Fix jsx renderer double closing elements (#36, thanks @marvinhagemeister)
• Fix babel preset issue causing babel-loader errors (#35)
• Fix dangerouslySetInnerHTML in JSX mode (#42, #46)
• Fix {nodeName:undefined} rendering [object Object] (#38, #47)

• Fix JSX render indenting empty lines in Preact 8 (developit/preact-jsx-chai#46, thanks @aotarola!)

• Prevent stateful re-rendering from being triggered during String rendering (developit/preact#524).

• Add slashes to self-closing tags to support both XHTML and HTML (#25, thanks @elliotdavies!)

• Add SVG xlink prop support with respect for foreignObject (thanks @wildlyinaccurate!)

• fix performance regression noticed by @lukeed

• Add support for boolean attributes with empty string value (#17, thanks @wyze)

• Don't render empty values as HTML comments (to match preact no longer doing so)

• Fix issue with Preact 6.1+ and the JSX mode where object values for the class prop were serialized as objects instead of their normalized string form

• Update to preact 6.1 and fix class/className massaging, fix class being left as an Object due to changes in Preact 6.1.

• Add special treatment for style and class DOM attributes to match DOM renderer

• Add support for disabling function and/or function name comparison in JSX mode
  • { functionNames:false } just serializes all function props as prop={Function}
  • { functions:false } turns off function serialization entirely
• Add skipFalseAttributes option - when set to false, turns off DOM attribute skipping (#4)

• Dont use self-closing tags in JSX mode

• Fix JSX rendering being non-deterministic about empty VNodes

• JSX Mode: skip attributes with null and undefined values
• JSX Mode: don't use self-closing tags as they make string assertions less useful

TL;DR: 3.0.0's {jsx:true} option has been replaced with preact-render-to-string/jsx.

3.0.0 added support for test-style JSX rendering (complex attributes rendered out using pretty-format). However, pretty-format actually doubled the size of preact-render-to-string and broke support for Node 4 and prior.

Instead of adding weight to the core library, which is often used in browsers (this library is part of preact-compat, for example), it's better to support these two "modes" via separate entrypoints into the module.

Here's the new solution - the library is now split into two different entrypoints, one for HTML/XML rendering, and the other specialized entry for JSX-style debug rendering.

Normal Mode

import renderToString from 'preact-render-to-string';

JSX-Style Mode (for test frameworks, debugging, etc)

import renderToString from 'preact-render-to-string/jsx';

• Add a { jsx:true } mode, which uses pretty-format to render complex JSX-style attribute values. This is useful for debugging purposes, and for preact-jsx-chai

Fixes

• #7 - Serialize object style attributes to style strings. Thanks @rmales!

Preact 5.2+ started passing Object style props through to the DOM better rendering performance, but that broke renderToString(). This fixes it!

Features

• #6 - Invoke componentWillMount() for stateful components just before render(). Thanks @mikestead!

• Add support for defaultProps on both pure and class components (#5)

• Skip children, key and ref attributes when rendering to HTML.

• Fix falsey and boolean attributes so they render properly in HTML and XML modes

• Add support for a {pretty:true} option, which outputs formatting whitespace. This release is dedicated to @drastick for his tenure.

prettyRender(
    <section>
        <a href="/foo">foo</a>
        bar
        <p>hello</p>
    </section>
);

// output:
<section>
    <a href="/foo">foo</a>
    bar
    <p>hello</p>
</section>

• Generate globally unique common names for unnamed components, instead of falling back to "Component".

  Unnamed components are now rendered as <UnnamedComponent0>, where 0 is an internal ID. Two identical components (referentially equal) will render with the same name, useful for testing unnamed components.

• Don't assume Function.prototype exists (it doesn't for ES2015 arrow functions)

• Add a renderRootComponent:false option, which skips rendering for components located at the root of the given JSX tree.

  Example:

  render(<Foo>a</Foo>) === '<Foo>a</Foo>'
  

• Add sortAttributes option. When set to true, attributes are sorted by name lexicographically during serialization. Useful for testing, such as via preact-jsx-chai

• Do not close void elements (#3 - thanks @i-like-robots!)

• Bugfix: Falsey values (false, null and undefined) are no longer incorrectly rendered as strings (Issue #2)

Breaking change: second argument to render() and shallowRender() is now context instead of options. options is now the third argument (see poll).

• Adds support for managing className VS class.
  • className takes precedence over class
  • either prop will only ever populate the HTML class attribute