v8.19.1

What's Changed

• feat: CSR/SSRv1 context by @jhefferman-sfdc in #5356

v8.19.0

Better types for template elements

TypeScript component authors can now specify a new property, __lwc_public_property_types__, to indicate to TypeScript which properties are available on the element created by a component. This prevents erroneous property definitions, which are otherwise unavoidable due to the way that TypeScript implements decorators.

Example

// <c-inferred-props>
class InferredProps extends LightningElement {
  @api exposed = 'hello'
  internal = 'secret'
}

// <c-explicit-props>
class ExplicitProps extends InferredProps {
  __lwc_public_property_types__?: {
    exposed: string
  }
}

class Container extends LightningElement {
  checkInferred() {
    const inferred = this.querySelector<LightningHTMLElement<InferredProps>>('c-inferred-props')!
    inferred.exposed // ✅ Valid, no type error
    inferred.internal // ❌ Invalid, but no type error!
  }

  checkExplicit() {
    const explicit = this.querySelector<LightningHTMLElement<ExplicitProps>>('c-explicit-props')!
    explicit.exposed // ✅ Valid, no type error
    explicit.internal // ✅ Invalid, and a type error occurs!
  }
}

In this example, the element interface for c-inferred-props is defined by LightningHTMLElement<InferredProps>. That interface has an erroneous property definition, internal. The internal property is part of the component interface, but is not decorated with @api, so it should not be part of the element interface.

The element interface for c-explicit-props is defined by LightningHTMLElement<ExplicitProps>. Because ExplicitProps defines __lwc_public_property_types__, the element interface does not include the internal property, which is the correct behavior.

What else changed?

• feat: make it pop! (over) @W-18425406 by @wjhsf in #5357
• chore: add summer25 def to nucleus.yaml by @jhefferman-sfdc in #5365
• feat(types): add hidden helper to make inferring element types better @W-18442478 by @wjhsf in #5362
• chore: bump version to 8.19.0 by @wjhsf in #5370
• chore: release 8.19.0 by @wjhsf in #5371

Full Changelog: v8.18.2...v8.19.0

v8.16.5

What's Changed

• fix: remove perf regression for signals re-enablement (256 patch) by @jhefferman-sfdc in #5358

v8.18.2

What's Changed

• chore: fix sauce labs integration by @divmain in #5342
• chore: update SL action to reference v3.0.0 by @divmain in #5343
• feat: add lwc:on directive by @divmain in #5344
• chore: remove perf regression for signals re-enablement by @jhefferman-sfdc in #5347
  Full Changelog: v8.18.0...v8.18.2

v8.18.1

What's Changed

• fix: invert locker contructor gate by @jhefferman-sfdc in #5337

v8.18.0

What's Changed

• chore: simplify style dedupe config by @wjhsf in #5271
• feat(ssr-compiler): only mutate things if we're in a component @W-17748892 by @wjhsf in #5310
• chore(ssr-compiler): remove fixed FIXMEs by @wjhsf in #5311
• chore: bump version to 8.17.0 by @wjhsf in #5317
• build(deps): bump vite from 6.2.3 to 6.2.4 by @dependabot in #5315
• build(deps): bump the theoretically-non-breaking group with 15 updates by @dependabot in #5313
• chore: re-introduce new constructor validation with gate by @jhefferman-sfdc in #5320
• fix(ssr): don't break on unused default templates @W-18170898 by @wjhsf in #5319
• test(decorators): add tests for decorated static props by @wjhsf in #5314
• fix(wire): connect wire before calling connectedCallback @W-18205007 by @wjhsf in #5322
• build(deps): bump vite from 6.2.4 to 6.2.5 by @dependabot in #5321
• build(deps): bump the theoretically-non-breaking group with 9 updates by @dependabot in #5323
• fix(ssr): address scope token test failures by @wjhsf in #5324
• build(deps): bump koa from 2.15.4 to 2.16.1 by @dependabot in #5325
• build(deps): bump vite from 6.2.5 to 6.2.6 by @dependabot in #5328
• chore(fixtures): remove some empty files by @wjhsf in #5326
• build(deps-dev): bump the theoretically-non-breaking group with 11 updates by @dependabot in #5332
• feat(release): add shell scripts to automate PR creation by @wjhsf in #5330
• chore: enable engine-server fixture tests in production mode @W-17972327 by @wjhsf in #5327
• chore: bump version to v8.18.0 by @wjhsf in #5333
• @W-18268582 chore: release 8.18.0 by @wjhsf in #5334

Full Changelog: v8.16.4...v8.18.0

v8.17.0

What's Changed

• chore: simplify style dedupe config by @wjhsf in #5271
  • WARNING: This is a breaking change for users of the experimental new SSR packages
• feat(ssr-compiler): only mutate things if we're in a component @W-17748892 by @wjhsf in #5310
• chore(ssr-compiler): remove fixed FIXMEs by @wjhsf in #5311
• chore: bump version to 8.17.0 by @wjhsf in #5317
• chore: release 8.17.0 @W-18174087 by @wjhsf in #5318

Full Changelog: v8.16.4...v8.17.0

v8.16.4

What's Changed

• chore(integration-karma): remove programmatic DSD check by @wjhsf in #5299
• chore(dependabot): separate out all @wdio packages by @wjhsf in #5300
• build(deps): bump vite from 6.0.11 to 6.2.3 by @dependabot in #5305
• chore(eslint): update config to catch .only and .skip files by @wjhsf in #5303
• fix(ssr): callable wire adapter behavior by @divmain in #5304

v8.16.3

What's Changed

• wire api fix by @jhefferman-sfdc in #5294

v8.16.2

What's Changed

• chore(rollup): use less confusing implementation for default true by @wjhsf in #5263
• chore: expose lwc-style register util by @wjhsf in #5277
• chore: use __lwc for transmogrified function names by @wjhsf in #5278
• chore: upgrade dependencies by @jye-sf in #5288
• fix: colliding error prop delta by @jhefferman-sfdc in #5287
• fix: added readonly function and tests by @jhefferman-sfdc in #5286