v2.0.0-rc.3

Breaking changes since v2.0.0-rc.1

• API: m.withAttr and m.prop were removed (#2317 @isiahmeadows)

Breaking changes

• API: Component vnode children are not normalized into vnodes on ingestion; normalization only happens if and when they are ingested by the view (#2155 (thanks to @magikstm for related optimization #2064))
• API: m.redraw() is always asynchronous (#1592)
• API: m.mount() will only render its own root when called, it will not trigger a redraw() (#1592)
• API: Assigning to vnode.state (as in vnode.state = ...) is no longer supported. Instead, an error is thrown if vnode.state changes upon the invocation of a lifecycle hook.
• API: m.request will no longer reject the Promise on server errors (eg. status >= 400) if the caller supplies an extract callback. This gives applications more control over handling server responses.
• hyperscript: when attributes have a null or undefined value, they are treated as if they were absent. #1773 (#2174)
• API: m.request errors no longer copy response fields to the error, but instead assign the parsed JSON response to error.response and the HTTP status code error.code.
• hyperscript: when an attribute is defined on both the first and second argument (as a CSS selector and an attrs field, respectively), the latter takes precedence, except for class attributes that are still added together. #2172 (#2174)
• stream: when a stream conditionally returns HALT, dependant stream will also end (#2200)
• render: remove some redundancy within the component initialization code (#2213)
• render: Align custom elements to work like normal elements, minus all the HTML-specific magic. (#2221)
• render: simplify component removal (#2214)
• cast className using toString (#2309)
• render: call attrs' hooks first, with express exception of onbeforeupdate to allow attrs to block components from even diffing (#2297)
• API: m.withAttr removed. (#2317)

News

• Mithril now only officially supports IE11, Firefox ESR, and the last two versions of Chrome/FF/Edge/Safari. (#2296)
• API: Introduction of m.redraw.sync() (#1592)
• API: Event handlers may also be objects with handleEvent methods (#1949, #2222).
• API: m.route.link accepts an optional options object (#1930)
• API: m.request better error message on JSON parse error - (#2195, @codeclown)
• API: m.request supports timeout as attr - (#1966)
• API: m.request supports responseType as attr - (#2193)
• Mocks: add limited support for the DOMParser API (#2097)
• API: add support for raw SVG in m.trust() string (#2097)
• render/core: remove the DOM nodes recycling pool (#2122)
• render/core: revamp the core diff engine, and introduce a longest-increasing-subsequence-based logic to minimize DOM operations when re-ordering keyed nodes.
• docs: Emphasize Closure Components for stateful components, use them for all stateful component examples.
• stream: Add stream.lift as a user-friendly alternative to merge -> map or combine #1944
• API: ES module bundles are now available for mithril and mithril/stream (#2194 @porsager).
  • All of the m.* properties from mithril are re-exported as named exports in addition to being attached to m.
  • m() itself from mithril is exported as the default export.
  • mithril/stream's primary export is exported as the default export.
• fragments: allow same attrs/children overloading logic as hyperscript (#2328)

Bug fixes

• API: m.route.set() causes all mount points to be redrawn (#1592)
• render/attrs: Using style objects in hyperscript calls will now properly diff style properties from one render to another as opposed to re-writing all element style properties every render.
• render/attrs All vnodes attributes are properly removed when absent or set to null or undefined #1804 #2082 (#1865, #2130)
• render/core: Render state correctly on select change event #1916 (#1918 @robinchew, #2052)
• render/core: fix various updateNodes/removeNodes issues when the pool and fragments are involved #1990, #1991, #2003, #2021
• render/core: fix crashes when the keyed vnodes with the same key had different tag values #2128 @JacksonJN (#2130)
• render/core: fix cached nodes behavior in some keyed diff scenarios #2132 (#2130)
• render/events: addEventListener and removeEventListener are always used to manage event subscriptions, preventing external interference.
• render/events: Event listeners allocate less memory, swap at low cost, and are properly diffed now when rendered via m.mount()/m.redraw().
• render/events: Object.prototype properties can no longer interfere with event listener calls.
• render/events: Event handlers, when set to literally undefined (or any non-function), are now correctly removed.
• render/hooks: fixed an ommission that caused oninit to be called unnecessarily in some cases #1992
• docs: tweaks: (#2104 @mikeyb, #2205, @cavemansspa, #2250 @isiahmeadows, #2265, @isiahmeadows)
• render/core: avoid touching Object.prototype.__proto__ setter with key: "__proto__" in certain situations (#2251)
• render/core: Vnodes stored in the dom node supplied to m.render() are now normalized #2266
• render/core: CSS vars can now be specified in {style} attributes (#2192 @barneycarroll), (#2311 @porsager), (#2312 @isiahmeadows)
• request: don't modify params, call extract/serialize/deserialize with correct this value (#2288)