@surface/custom-element/internal/metadata/static-metadata.js

Provides support of directives and data binding on custom elements.

export const STATIC_METADATA = Symbol("custom-element:static-metadata");
export default class StaticMetadata {
    constructor() {
        this.converters = {};
        this.shadowRootInit = { mode: "open" };
        this.observedAttributes = [];
        this.styles = [];
    }
    static from(target) {
        if (!Reflect.has(target, STATIC_METADATA)) {
            Reflect.defineProperty(target, STATIC_METADATA, { configurable: false, enumerable: false, value: new StaticMetadata() });
        }
        else if (!target.hasOwnProperty(STATIC_METADATA)) {
            Reflect.defineProperty(target, STATIC_METADATA, { configurable: false, enumerable: false, value: Reflect.get(target, STATIC_METADATA).inherit() });
        }
        return Reflect.get(target, STATIC_METADATA);
    }
    inherit() {
        const clone = new StaticMetadata();
        clone.converters = { ...this.converters };
        clone.observedAttributes = [...this.observedAttributes];
        clone.styles = [...this.styles];
        return clone;
    }
}