| 1 | {"version":3,"file":"lit-element.js","sources":["src/lit-element.ts"],"sourcesContent":["/**\n * @license\n * Copyright 2017 Google LLC\n * SPDX-License-Identifier: BSD-3-Clause\n */\n\n/**\n * The main LitElement module, which defines the [[`LitElement`]] base class and\n * related APIs.\n *\n * LitElement components can define a template and a set of observed\n * properties. Changing an observed property triggers a re-render of the\n * element.\n *\n * Import [[`LitElement`]] and [[`html`]] from this module to create a\n * component:\n *\n * ```js\n * import {LitElement, html} from 'lit-element';\n *\n * class MyElement extends LitElement {\n *\n * // Declare observed properties\n * static get properties() {\n * return {\n * adjective: {}\n * }\n * }\n *\n * constructor() {\n * this.adjective = 'awesome';\n * }\n *\n * // Define the element's template\n * render() {\n * return html`<p>your ${adjective} template here</p>`;\n * }\n * }\n *\n * customElements.define('my-element', MyElement);\n * ```\n *\n * `LitElement` extends [[`ReactiveElement`]] and adds lit-html templating.\n * The `ReactiveElement` class is provided for users that want to build\n * their own custom element base classes that don't use lit-html.\n *\n * @packageDocumentation\n */\nimport {PropertyValues, ReactiveElement} from '@lit/reactive-element';\nimport {render, RenderOptions, noChange, RootPart} from 'lit-html';\nexport * from '@lit/reactive-element';\nexport * from 'lit-html';\n\n// For backwards compatibility export ReactiveElement as UpdatingElement. Note,\n// IE transpilation requires exporting like this.\nexport const UpdatingElement = ReactiveElement;\n\nconst DEV_MODE = true;\n\nlet issueWarning: (code: string, warning: string) => void;\n\nif (DEV_MODE) {\n // Ensure warnings are issued only 1x, even if multiple versions of Lit\n // are loaded.\n const issuedWarnings: Set<string | undefined> =\n (globalThis.litIssuedWarnings ??= new Set());\n\n // Issue a warning, if we haven't already.\n issueWarning = (code: string, warning: string) => {\n warning += ` See https://lit.dev/msg/${code} for more information.`;\n if (!issuedWarnings.has(warning)) {\n console.warn(warning);\n issuedWarnings.add(warning);\n }\n };\n}\n\n/**\n * Base element class that manages element properties and attributes, and\n * renders a lit-html template.\n *\n * To define a component, subclass `LitElement` and implement a\n * `render` method to provide the component's template. Define properties\n * using the [[`properties`]] property or the [[`property`]] decorator.\n */\nexport class LitElement extends ReactiveElement {\n /**\n * Ensure this class is marked as `finalized` as an optimization ensuring\n * it will not needlessly try to `finalize`.\n *\n * Note this property name is a string to prevent breaking Closure JS Compiler\n * optimizations. See @lit/reactive-element for more information.\n */\n protected static override ['finalized'] = true;\n\n // This property needs to remain unminified.\n static ['_$litElement$'] = true;\n\n /**\n * @category rendering\n */\n readonly renderOptions: RenderOptions = {host: this};\n\n private __childPart: RootPart | undefined = undefined;\n\n /**\n * @category rendering\n */\n protected override createRenderRoot() {\n const renderRoot = super.createRenderRoot();\n // When adoptedStyleSheets are shimmed, they are inserted into the\n // shadowRoot by createRenderRoot. Adjust the renderBefore node so that\n // any styles in Lit content render before adoptedStyleSheets. This is\n // important so that adoptedStyleSheets have precedence over styles in\n // the shadowRoot.\n this.renderOptions.renderBefore ??= renderRoot!.firstChild as ChildNode;\n return renderRoot;\n }\n\n /**\n * Updates the element. This method reflects property values to attributes\n * and calls `render` to render DOM via lit-html. Setting properties inside\n * this method will *not* trigger another update.\n * @param changedProperties Map of changed properties with old values\n * @category updates\n */\n protected override update(changedProperties: PropertyValues) {\n // Setting properties in `render` should not trigger an update. Since\n // updates are allowed after super.update, it's important to call `render`\n // before that.\n const value = this.render();\n if (!this.hasUpdated) {\n this.renderOptions.isConnected = this.isConnected;\n }\n super.update(changedProperties);\n this.__childPart = render(value, this.renderRoot, this.renderOptions);\n }\n\n /**\n * Invoked when the component is added to the document's DOM.\n *\n * In `connectedCallback()` you should setup tasks that should only occur when\n * the element is connected to the document. The most common of these is\n * adding event listeners to nodes external to the element, like a keydown\n * event handler added to the window.\n *\n * ```ts\n * connectedCallback() {\n * super.connectedCallback();\n * addEventListener('keydown', this._handleKeydown);\n * }\n * ```\n *\n * Typically, anything done in `connectedCallback()` should be undone when the\n * element is disconnected, in `disconnectedCallback()`.\n *\n * @category lifecycle\n */\n override connectedCallback() {\n super.connectedCallback();\n this.__childPart?.setConnected(true);\n }\n\n /**\n * Invoked when the component is removed from the document's DOM.\n *\n * This callback is the main signal to the element that it may no longer be\n * used. `disconnectedCallback()` should ensure that nothing is holding a\n * reference to the element (such as event listeners added to nodes external\n * to the element), so that it is free to be garbage collected.\n *\n * ```ts\n * disconnectedCallback() {\n * super.disconnectedCallback();\n * window.removeEventListener('keydown', this._handleKeydown);\n * }\n * ```\n *\n * An element may be re-connected after being disconnected.\n *\n * @category lifecycle\n */\n override disconnectedCallback() {\n super.disconnectedCallback();\n this.__childPart?.setConnected(false);\n }\n\n /**\n * Invoked on each update to perform rendering tasks. This method may return\n * any value renderable by lit-html's `ChildPart` - typically a\n * `TemplateResult`. Setting properties inside this method will *not* trigger\n * the element to update.\n * @category rendering\n */\n protected render(): unknown {\n return noChange;\n }\n}\n\n// Install hydration if available\nglobalThis.litElementHydrateSupport?.({LitElement});\n\n// Apply polyfills if available\nconst polyfillSupport = DEV_MODE\n ? globalThis.litElementPolyfillSupportDevMode\n : globalThis.litElementPolyfillSupport;\npolyfillSupport?.({LitElement});\n\n// DEV mode warnings\nif (DEV_MODE) {\n /* eslint-disable @typescript-eslint/no-explicit-any */\n // Note, for compatibility with closure compilation, this access\n // needs to be as a string property index.\n (LitElement as any)['finalize'] = function (this: typeof LitElement) {\n const finalized = (ReactiveElement as any).finalize.call(this);\n if (!finalized) {\n return false;\n }\n const warnRemovedOrRenamed = (obj: any, name: string, renamed = false) => {\n if (obj.hasOwnProperty(name)) {\n const ctorName = (typeof obj === 'function' ? obj : obj.constructor)\n .name;\n issueWarning(\n renamed ? 'renamed-api' : 'removed-api',\n `\\`${name}\\` is implemented on class ${ctorName}. It ` +\n `has been ${renamed ? 'renamed' : 'removed'} ` +\n `in this version of LitElement.`\n );\n }\n };\n warnRemovedOrRenamed(this, 'render');\n warnRemovedOrRenamed(this, 'getStyles', true);\n warnRemovedOrRenamed((this as typeof LitElement).prototype, 'adoptStyles');\n return true;\n };\n /* eslint-enable @typescript-eslint/no-explicit-any */\n}\n\n/**\n * END USERS SHOULD NOT RELY ON THIS OBJECT.\n *\n * Private exports for use by other Lit packages, not intended for use by\n * external users.\n *\n * We currently do not make a mangled rollup build of the lit-ssr code. In order\n * to keep a number of (otherwise private) top-level exports mangled in the\n * client side code, we export a _$LE object containing those members (or\n * helper methods for accessing private fields of those members), and then\n * re-export them for use in lit-ssr. This keeps lit-ssr agnostic to whether the\n * client-side code is being used in `dev` mode or `prod` mode.\n *\n * This has a unique name, to disambiguate it from private exports in\n * lit-html, since this module re-exports all of lit-html.\n *\n * @private\n */\nexport const _$LE = {\n _$attributeToProperty: (\n el: LitElement,\n name: string,\n value: string | null\n ) => {\n // eslint-disable-next-line\n (el as any)._$attributeToProperty(name, value);\n },\n // eslint-disable-next-line\n _$changedProperties: (el: LitElement) => (el as any)._$changedProperties,\n};\n\n// IMPORTANT: do not change the property name or the assignment expression.\n// This line will be used in regexes to search for LitElement usage.\n(globalThis.litElementVersions ??= []).push('3.0.2');\nif (DEV_MODE && globalThis.litElementVersions.length > 1) {\n issueWarning!(\n 'multiple-versions',\n `Multiple versions of Lit loaded. Loading multiple versions ` +\n `is not recommended.`\n );\n}\n"],"names":["UpdatingElement","ReactiveElement","LitElement","constructor","this","host","undefined","createRenderRoot","renderRoot","super","renderOptions","renderBefore","firstChild","update","changedProperties","value","render","hasUpdated","isConnected","__childPart","connectedCallback","setConnected","disconnectedCallback","noChange","globalThis","litElementHydrateSupport","polyfillSupport","litElementPolyfillSupport","_$LE","_$attributeToProperty","el","name","_$changedProperties","litElementVersions","push"],"mappings":";;;;;iBAuDaA,EAAkBC,QA8BlBC,UAAmBD,EAAhCE,kCAgBWC,mBAA+B,CAACC,KAAMD,MAEvCA,eAAoCE,EAKzBC,2BACjB,MAAMC,EAAaC,MAAMF,mBAOzB,oBADAH,KAAKM,eAAcC,8BAAAA,aAAiBH,EAAYI,YACzCJ,EAUUK,OAAOC,GAIxB,MAAMC,EAAQX,KAAKY,SACdZ,KAAKa,aACRb,KAAKM,cAAcQ,YAAcd,KAAKc,aAExCT,MAAMI,OAAOC,GACbV,KAAKe,KAAcH,EAAOD,EAAOX,KAAKI,WAAYJ,KAAKM,eAuBhDU,0BACPX,MAAMW,8BACNhB,KAAKe,qBAAaE,cAAa,GAsBxBC,6BACPb,MAAMa,iCACNlB,KAAKe,qBAAaE,cAAa,GAUvBL,SACR,OAAOO,GAtGiBrB,EAAY,WAAI,EAGnCA,EAAgB,eAAI,YAwG7BsB,WAAWC,8CAAXD,WAAsC,CAACtB,WAAAA,IAGvC,MAAMwB,EAEFF,WAAWG,0BACfD,MAAAA,GAAAA,EAAkB,CAACxB,WAAAA,UAkDN0B,EAAO,CAClBC,KAAuB,CACrBC,EACAC,EACAhB,KAGCe,EAAWD,KAAsBE,EAAMhB,IAG1CiB,KAAsBF,GAAoBA,EAAWE,iBAKtDR,WAAWS,kCAAXT,WAAWS,mBAAuB,IAAIC,KAAK"} |