All files / src/custom-element/mixins/core PropertyMetadataInitializerMixin.ts

100% Statements 35/35
94.12% Branches 16/17
100% Functions 7/7
100% Lines 34/34

Press n or j to go to the next uncovered block, b, p or k for the previous block.

1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60 61 62 63 64 65 66 67 68 69 70 71 72 73 74 75 76 77 78 79 80 81 82 83 84 85 86 87 88 89 90 91 92 93 94 95 96 97 98 99 100 101 102 103 104 105 106 107 108 109 110 111 112 113 114 115 116 117 118 119 120 121 122 123 124 125 126 127 128 129 130 131 132              21x   31x                 134x   368x       134x   134x   134x   134x   5x   5x   5x                         368x     368x   291x     368x                 253x   253x   253x   120x     253x       19x     234x       13x               368x       368x     368x     368x                 134x   134x   134x   1349x   114x     1349x     134x        
import { CustomElementMetadata, CustomElementPropertyMetadata } from "../../interfaces";
 
/**
 * Initializes the properties of a custom element from the metadata configured
 * @param Base The base class to extend
 * @returns The mixin class
 */
export default function PropertyMetadataInitializerMixin(Base): any {
 
    return class PropertyMetadataInitializer extends Base {
 
        /**
         * The properties to track in the class
         */
        static properties: () => Record<string, CustomElementPropertyMetadata>;
 
        protected static initalizeProperties(metadata: CustomElementMetadata): void {
 
            const properties = this.getAllProperties();
 
            Object.entries(properties).forEach(([key, value]) => this._initializeProperty(key, value, metadata));
 
            // Merge the properties of the base class if any so we can validate and initialize
            // the values of the properties of the base class in the instance
            let baseClass = Object.getPrototypeOf(this.prototype)?.constructor;
 
            Eif (baseClass !== undefined) {
 
                const baseClassMetadata = baseClass.metadata;
 
                if (baseClassMetadata !== undefined) {
 
                    metadata.properties = new Map([...metadata.properties, ...baseClassMetadata.properties]);
 
                    metadata.propertiesByAttribute = new Map([...metadata.propertiesByAttribute, ...baseClassMetadata.propertiesByAttribute]);
 
                    metadata.observedAttributes = [...metadata.observedAttributes, ...baseClassMetadata.observedAttributes];
                }
            }
        }
 
        /**
         * Creates the setters and getters for the property
         * @param name 
         * @param propertyMetadata 
         * @returns The name of the observed attribute for that property
         */
        private static _initializeProperty(name: string, propertyMetadata: CustomElementPropertyMetadata, metadata: CustomElementMetadata): void {
 
            propertyMetadata.name = name; // Set the name of the property
 
            // Set the name of the attribute as same as the name of the property if no attribute name was provided
            if (propertyMetadata.attribute === undefined) {
 
                propertyMetadata.attribute = name;
            }
 
            Object.defineProperty(
                this.prototype,
                name,
                {
                    get(): any {
 
                        let {
                            type,
                            defer
                        } = propertyMetadata;
 
                        const value = this._properties[name];
 
                        if (!Array.isArray(type)) {
 
                            type = [type];
                        }
 
                        if (type.includes(Function) &&
                            typeof value === 'function' &&
                            defer !== true) { // Only call the function if the type is a Function and it is not deferred
 
                            return value();
                        }
 
                        return value;
                    },
                    set(this: any, value: unknown) {
 
                        this.setProperty(name, value);
                    },
                    configurable: true,
                    enumerable: true,
                }
            );
 
            // Add it to the metadata properties so the properties of the instances can be validated and initialized
            metadata.properties.set(name, propertyMetadata);
 
            const {
                attribute
            } = propertyMetadata;
 
            // Index the property descriptor by the attribute name
            metadata.propertiesByAttribute.set(attribute, propertyMetadata); // Index by attribute name
 
            // Add the observed attribute
            metadata.observedAttributes.push(propertyMetadata.attribute.toLowerCase());
        }
 
        /**
         * Retrieve the state of this and the base mixins
         * @returns The merged state
         */
        static getAllProperties(): Record<string, CustomElementPropertyMetadata> {
 
            let properties = this.properties || {};
 
            let baseClass = Object.getPrototypeOf(this.prototype)?.constructor;
 
            while (baseClass._isMetadataInitializer === true) {
 
                if (baseClass.properties !== undefined) {
 
                    properties = { ...properties, ...baseClass.properties };
                }
 
                baseClass = Object.getPrototypeOf(baseClass.prototype)?.constructor;
            }
 
            return properties;
        }
    }
}