• #5218 be6b275035079db3239be4019c4f93c2b1f32428 Thanks @louis-bompart! - Ensure the ref directive disconnect gracefuly when its internal ref is undefined.

• #5044 0d0170e87b06edd8295a31893c820162d0f16a23 Thanks @ava-cassiopeia! - Make ClassInfo mutable

• #4999 6c174c8d0ed0230ba765d699591d933d7ab5d4bb - Fix a bug in change detection with decorated standard private accessors.

• #4997 aea85e24 - Update README

• #4988 6792b7ef Thanks @ADNolan! - Adjusted the comparison to use the name property of the _$resolve function and the resolveOverrideFn in private ssr support to prevent duplicated patching of the directive class.

• #4976 a126d8df - Fix minor regression in property converters. fromAttribute may return either null or undefined.

• #4901 c9160405 Thanks @maxpatiiuk! - Dev mode warnings are now emitted on the next microtask after package import, allowing for a wider opportunity to suppress the warnings by consumers.

• #4934 4824c4ce - Adds property option for useDefault. When set, the initial default value is not considered a change and does not reflect when reflect is set. In addition, when the attribute is removed, the default value is restored.

• #4949 3e2f87f6 - fixes inconsistent initial changed properties values

• #4956 0a9bc720 Thanks @louis-bompart! - Import barrels explicitly for compatibility with modern Node resolution w/ ESM

• Updated dependencies [c9160405, 3e2f87f6, 4824c4ce, 0a9bc720]:

  • @lit/reactive-element@2.1.0
  • lit-element@4.2.0
  • lit-html@3.3.0

• #4782 99703a03 - Revert the Terser plugin for Rollup to rollup-plugin-terser from @rollup/plugin-terser due to a bug that prevented our minified name prefixing from working.

• #4637 feccc1ba - Add MathML support with the mathml template tag

• Updated dependencies [feccc1ba]:
  • lit-html@3.2.0
  • lit-element@4.1.0

• #4646 abf30b3e - The value provided by the ref() directive will always be undefined when the element is disconnected.

• #4570 bd881370 - Fix the lit-html marker length to be consistently 9 characters.

• #4523 1a32b61e - Add a DEV_MODE error to catch duplicate attribute bindings that otherwise create silent errors.

• #4485 57b00630 - Add "browser" export condition entrypoints to any package.json files with "node" export conditions. This fixes Node test runners emulating browser environments that were incorrectly loading the "node" entrypoints instead of the browser code.

• Updated dependencies [1a32b61e, 57b00630, dca963f7]:

  • lit-html@3.1.2
  • @lit/reactive-element@2.0.4
  • lit-element@4.0.4

• #4409 1af7991c - asyncReplace correctly re-renders when value is unchanged (#4408)

• #4473 9a4d569f - Add a warning in dev mode when binding this.requestUpdate directly as an event listener.

• #4413 f60a3a2c - Remove unused internal parameters to requestUpdate()

• #4309 949a5467 - Adds two new types: UncompiledTemplateResult and MaybeCompiledTemplateResult. Currently UncompiledTemplateResult is the same as TemplateResult, and MaybeCompiledTemplateResult is the union of the compiled and uncompiled types.

• #4387 bf551b5b - Ensure renderRoot exists before first update (#4268)

• #4282 c7922a0c Thanks @MaxArt2501! - Fix a bug where accessing a @query decorated field with the cache flag set before the first update would result in null being cached permanently. null will no longer be cached before the first update and in DEV_MODE now raises a warning.

• #4388 839ca0f8 - Fixes bug where adding or removing controllers during a reactive controller lifecycle would affect the execution of other controllers (#4266). Controllers can now be added/removed during lifecycle without affecting others.

• Updated dependencies [949a5467]:

  • lit-html@3.1.0

• #4345 02b8d620 - Add a dev mode warning if a static value such as literal or unsafeStatic is detected within the non-static html tag function. These should only be used with the static html tag function imported from lit-html/static.js or lit/static-html.js.

• #4240 edf998c9 Thanks @remziatay! - Improved the type inferece of the choose() directive to properly restrict the case type inferred from provided value. Note: If this change creates a type error in your code, there must have been an unreachable case that can be removed, or the type of your value might be missing a valid case in the union.

• #4310 8f674ab3 Thanks @megheaiulian! - The when() directive now calls the case functions with the provided condition value as an argument. This allows the narrowing of types for the condition value based on its truthiness when used as a parameter for the case function.

• #4284 89a5b088 - Allow null to be in the type of @query() decorated fields

• #3756 f06f7972 - Drop IE11 support

• #4146 0f6878dc - Generated accessor for reactive properties now wrap user accessors and automatically call this.requestUpdate() in the setter. As in previous versions, users can still specify noAccessor: true, in which case they should call this.requestUpdate() themselves in the setter if they want to trigger a reactive update.

• #3765 92cedaa2 - Remove experimental hydrate modules. These are available from @lit-labs/ssr-client.

• #3850 7e8491d4 - Delete deprecated queryAssignedNodes behavior and arguments.

  Migrate deprecated usage with a selector argument to use @queryAssignedElements. E.g.: @queryAssignedNodes('list', true, '.item') to @queryAssignedElements({slot: '', flatten: false, selector: '.item'}).

• #4254 1040f758 - Change the type of ReactiveElement.renderRoot and return type of ReactiveElement.createRenderRoot() to be HTMLElement | DocumentFragment to match each other and lit-html's render() method.

• #3759 1db01376 - Use replaceWith() for SVG templates

• #3751 dfd747cf - Simplify lit-html attribute handling for standards-compliant browsers that iterate attributes in source order

• #3750 c3e473b4 - Use toggleAttribute() to simplify boolean attribute parts

• #3896 2eba6997 - Warn on async overrides of performUpdate()

• #4183 6470807f - Make the decorators work with the accessor keyword when experimentalDecorators is true.

• #4141 6b515e43 - Update TypeScript to ~5.2.0

• #3710 09949234 - Add undefined to the return type of PropertyValues.get()

• #3762 23c404fd - Remove Lit 1 -> Lit 2 migration warnings

• #3918 2a01471a - Some code golf on ReactiveElement

• #3809 6f2833fd - Use for/of loops in more places

• Updated dependencies:

  • @lit/reactive-element@2.0.0
  • lit-html@3.0.0
  • lit-element@4.0.0

• #4146 0f6878dc - Generated accessor for reactive properties now wrap user accessors and automatically call this.requestUpdate() in the setter. As in previous versions, users can still specify noAccessor: true, in which case they should call this.requestUpdate() themselves in the setter if they want to trigger a reactive update.

• #3896 2eba6997 - Warn on async overrides of performUpdate()

• #4081 d27a77ec - Sync from last stable release

• #4183 6470807f - Make the decorators work with the accessor keyword when experimentalDecorators is true.

• #4141 6b515e43 - Update TypeScript to ~5.2.0

• #3918 2a01471a - Some code golf on ReactiveElement

• #3710 09949234 - Add undefined to the return type of PropertyValues.get()

• Updated dependencies [6b515e43, 0f6878dc, 2a01471a, 2eba6997, d27a77ec, 6470807f, 09949234]:

  • @lit/reactive-element@2.0.0-pre.1
  • lit-element@4.0.0-pre.1
  • lit-html@3.0.0-pre.1

• #3751 dfd747cf - Simplify lit-html attribute handling for standards-compliant browsers that iterate attributes in source order

• #3759 1db01376 - Use replaceWith() for SVG templates

• #3750 c3e473b4 - Use toggleAttribute() to simplify boolean attribute parts

• #3765 92cedaa2 - Remove experimental hydrate modules. These are available from @lit-labs/ssr-client.

• #3756 f06f7972 - Drop IE11 support

• #3762 23c404fd - Remove Lit 1 -> Lit 2 migration warnings

• #3814 23326c6b - Update to TypeScript v5.0

• Updated dependencies [be72f66b, dfd747cf, 23c404fd, 76795a18, 1db01376, 6f2833fd, c3e473b4, 92cedaa2, 7e8491d4, 23326c6b, f06f7972, 76795a18]:

  • @lit/reactive-element@2.0.0-pre.0
  • lit-html@3.0.0-pre.0
  • lit-element@4.0.0-pre.0

• #3993 e2c50569 - Fix return type of isTemplateResult helper to include the CompiledTemplateResult and fix the cache directive to work correctly with CompiledTemplateResults. Also add an explicit isCompiledTemplateResult helper.

• #4031 8057c78d - Rename ReactiveElement._initialize to __initialize, make it private, and remove the @internal annotation. This will help prevent collisions with subclasses that implement their own _initialize method, while using development builds.

• Updated dependencies [e2c50569]:

  • lit-html@2.8.0

• #3968 5bb40831 - Allow undefined to be passed to the ref() directive

• #3969 7d8d4a15 - Make RefOrCallback generic like Ref

• #3987 bb2560f1 - Change the h field of CompiledTemplates to a TemplateStringsArray preventing the spoofing of CompiledTemplates by JSON injection attacks. This should not be a breaking change for most users unless you're using CompiledTemplates. This is a necessary security fix, similar to #2307.

• #3917 f6387e35 - Allow decorators to accept ReactiveElement class from a different source.

• #3871 308280eb - remove test directory from npm publication

• #3825 343187b1 - static-html no longer adds an item to TemplateResult's value array for the last consumed static value. This fixes an error with server-side rendering of static html.

• #3766 4431cbb8 - Fix styleMap initial render of mixed-case custom props

• #3788 88fe0390 - Allow numbers to be used as values in styleMap()

• #3768 7c1191da - Fix styleMap's handling of important flags

• #3720 575fb578 - lit-html/experimental-hydrate.js and lit-element/experimental-hydrate-support.js have been moved to @lit-labs/ssr-client.

  The modules in the original location have been marked deprecated and will be removed in a future version.

• #3677 b95c86e5 - [SSR only] Reflect ARIA attributes onto server rendered Lit elements with attached internals during SSR and remove them upon hydration.

• #3667 e00f6f52 - [SSR only] Improved how nodes with attribute/property/event/element bindings are rendered in SSR, to avoid adding comments inside of "raw text elements" like <textarea>. Fixes #3663.

  Note: @lit-labs/ssr and lit-html must be updated together.

• #3583 88a40177 - [SSR only] Add more detail to some hydration errors

• Updated dependencies [4d698430, b95c86e5, e00f6f52, 88a40177]:

  • lit-html@2.7.0
  • lit-element@3.3.0

• #3526 65e56655 - Disable ShadyDOM noPatch in Node dev build. This fixes the issue of throwing due to undefined window.

• #3561 e5c254e9 - Fix built-in shimming of HTMLElement for Node build of reactive-element to respect existing HTMLElement in global

• #3522 72fcf0d7 - When running in Node, Lit now automatically includes minimal DOM shims which are sufficient for most SSR (Server Side Rendering) use-cases, removing the need to import the global DOM shim from @lit-labs/ssr.

  The new @lit-labs/ssr-dom-shim package has been introduced, which exports an HTMLElement, CustomElementRegistry, and default customElements singleton.

  The existing @lit-labs/ssr global DOM shim can still be used, and is compatible with the new package, because @lit-labs/ssr imports from @lit-labs/ssr-dom-shim. Importing the global DOM shim adds more APIs to the global object, such as a global HTMLElement, TreeWalker, fetch, and other APIs. It is recommended that users try to remove usage of the @lit-labs/ssr DOM shim, and instead rely on the more minimal, automatic shimming that @lit/reactive-element now provides automatically.

• Updated dependencies [72fcf0d7]:
  • @lit/reactive-element@1.6.0
  • lit-html@2.6.0

• #3507 b152db29 - lit-html and reactive-element now include development Node builds with unminified code and dev warnings.

• Updated dependencies [b152db29]:
  • lit-html@2.5.0
  • @lit/reactive-element@1.5.0

• #3374 bb098950 - Initializers added to subclasses are no longer improperly added to superclass.

• #3318 21313077 - Adds an isServer variable export to lit and lit-html/is-server.js which will be true in Node and false in the browser. This can be used when authoring components to change behavior based on whether or not the component is executing in an SSR context.

• #3320 305852d4 - The lit package now specifies and "types" export condition allowing TypeScript moduleResolution to be nodenext.

• Updated dependencies [21313077]:

  • lit-html@2.4.0

• #3222 486739ec - Fix CSSStyleSheet is not defined error that would occur when importing a Lit component in Node when both static styles and the @property decorator were used.

• #3223 5a65ca97 - Use existing document in Node build

• #3156 ae6f6808 - Lit and its underlying libraries can now be imported directly from Node without crashing, without the need to load the @lit-labs/ssr dom-shim library. Note that actually rendering from a Node context still requires the @lit-labs/ssr dom-shim, and the appropriate integration between @lit-labs/ssr and your framework/tool.

• #3003 daddeb34 - Lit's async-directive now re-exports everything from the directive module.

• #3120 6361a4b4 - Bind this to custom attribute converter methods

• Updated dependencies [daddeb34, 0725fdb4, 3766ae4c, 6361a4b4, ae6f6808]:

  • lit-html@2.3.0
  • @lit/reactive-element@1.4.0

• #3130 1f0567f1 - Export the underlying type of the keyed directive.

• #3132 2fe2053f - Added "types" entry to package exports. This tells newer versions of TypeScript where to look for typings for each module.

• #2978 634d4560 - Changed the caching behavior of the css`` template literal tag so that same-text styles do not share a CSSStyleSheet. Note that this may be a breaking change in some very unusual scenarios on Chromium and Firefox > 101 only.

• #2849 b12e8d93 - Expand documentation for render and TemplateResult.

• #2952 a78cc3b7 - Fix SSR hydration bug relating to and other void elements having attribute bindings.

• #2847 79d82385 - Fix typo in API docs for live() directive.

• #2828 b3b6bc33 - Remove private Lit 2 migration helpers: INTERNAL and clearContainerForLit2MigrationOnly. This logic is no longer depended on.

• #2732 3e181bcb - Enforce use of file extensions in imports. Fixes an issue with older TypeScript compilers.

• #2688 ef178ef6 - Add explicit types to the jsdoc code samples for query, queryAll, and queryAsync.

• #2657 a6069c40 - Remove readonly restriction from StyleInfo interface as addition, deletion, and updating of styles is valid. Expanded styleMap documentation with links to lit.dev.

• #2642 badc532c - Add an additional security brand check to StaticValues; Similar to #2307

• #2691 171143bd - Fixes ref bug when auto-bound class method used as a callback could incorrectly receive undefined.

• #2661 9a3a38cd - Give a clearer error message when rendering into null/undefined

• #2646 365cd09a - Clarify that hacking around the template strings array brand error can create security vulnerabilities.

• #2635 ae358703 - Make the event debug logger lazier, doing even less work (with no side effects) even in dev mode unless the page has opted in.

• #2401 2c9d0008 - Added a devlog events system that may be used for debugging and visualizing Lit's internals.

• Updated dependencies [2c9d0008]:
  • lit-element@3.2.0
  • lit-html@2.2.0
  • @lit/reactive-element@1.3.0

• #2518 bbbf21d4 - Fix breaking change in the PropertyValues type. Make PropertyValues compatible with Map<string, string> and other Map types.

• #2526 a50d188a - Export PropertyValueMap such that JavaScript generated by Google Closure Compiler can reference this type. Do not directly import the PropertyValueMap interface.

• #2498 2a1dc7a1 - Replace 'rare' with 'invalid' in svg tag function JSDocs.

• #2459 23df9d45 - Fix bindings inside of <title> elements

• #2482 6ea3d6c4 - Update the definition of the PropertyValues type to give better types to .get(k). .get(k) is now defined to return the correct type when using PropertyValues<this> and a parameter that's a key of the element class.

• #2464 df4e1a46 - Fix type signature in queryAssignedNodes JSDoc code example.

• #2479 89560520 - Expand JSDocs for the svg tagged template literal (TTL). The new documentation makes it more clear that the svg tag function should only be used for SVG fragments, and not for the <svg> HTML element.

• #2457 48d69184 - Add JSDoc to the willUpdate lifecycle callback. Expand the docs for firstUpdated, and attributeChangedCallback. Minor code sample fixes.

• #2399 5ac025bf - Correct typo in async-directive module comment

• #2370 7453e365 - Replace square bracket links with the linkcode JSDoc tag. Editors will create a jump to definition hyperlink for the linkcode tag if the identifier is in scope.

• #2410 b9a6962b - Correct the link path of CONTRIBUTING.md in README.md files

• #2384 39b8db85 - Fix missing decorators/query-assigned-elements.js file

• #2380 00cd8533 - Fix choose directive default export path.

• #2337 fcc2b3d0 - Add a keyed(key, value) directive that clears a part if the key changes.

• #2327 49ecf623 - Add queryAssignedElements decorator for a declarative API that calls HTMLSlotElement.assignedElements() on a specified slot. selector option allows filtering returned elements with a CSS selector.

• #2341 1d563e83 - Add choose() directive

• Updated dependencies [08e7fc56, fcc2b3d0, eb5c5d2b, 49ecf623, 26e3fb7b, d319cf5f, 1d563e83, 221cb0a9]:
  • @lit/reactive-element@1.1.0
  • lit-html@2.1.0
  • lit-element@3.1.0

• #2234 de17a7d4 - Fix repository.directory field in lit package.json

• #2232 d808d234 - Add lit logo to NPM package

• New package serving as the main entry point for all users of Lit (including LitElement, ReactiveElement, and lit-html). See the Migration Guide for more details.

• #2103 15a8356d - Updates the exports field of package.json files to replace the subpath folder mapping syntax with an explicit list of all exported files.

  The /-suffixed syntax for subpath folder mapping originally used in these files is deprecated. Rather than update to the new syntax, this change replaces these mappings with individual entries for all exported files so that (a) users must import using extensions and (b) bundlers or other tools that don't resolve subpath folder mapping exactly as Node.js does won't break these packages' expectations around how they're imported.

• #2113 5b2f3642 - Dependency upgrades including TypeScript 4.4.2

• #2073 0312f3e5 - (Cleanup) Removed obsolete TODOs from codebase

• #1942 c8fe1d4 - For minified class fields on classes in lit libraries, added prefix to stable properties to avoid collisions with user properties.

• #1959 6938995 - Changed prefix used for minifying class field names on lit libraries to stay within ASCII subset, to avoid needing to explicitly set the charset for scripts in some browsers.

• #1964 f43b811 - Don't publish src/ to npm.

• Updated dependencies [ff0d1556, 5768cc60, 69389958, 5fabe2b5, 52a47c7e, 5fabe2b5, 5fabe2b5, 5fabe2b5, f05be301, 5fabe2b5, 56e8efd3, 662209c3, a791514b, 5fabe2b5]:

  • lit-html@2.0.0-rc.4

Changes below were based on the Keep a Changelog format. All changes above are generated automatically by Changesets.

• Updated dependencies

• (Since 2.0.0-pre.1) Renamed hydrate and hydrate-support modules to experimental-hydrate and experimental-hydrate-support, respectively, to reflect their experimental nature. Experimental modules may undergo breaking changes within otherwise non-major releases.

• Updated dependencies

Initial release