test.js

import { LightningElement, api, track, wire } from 'lwc';
import { unstable_createContentDocumentAndVersion, createRecord } from 'lightning/uiRecordApi';
import { ShowToastEvent } from 'lightning/platformShowToastEvent';

export default class FileUpload extends LightningElement {
    @api
    recordId;

    @track
    files = undefined;

    @track
    uploadingFile = false;

    @track
    titleValue = '';

    @track
    descriptionValue = '';

    @track
    errorMessage = '';

    get recordId() {
        return recordId;
    }

    /* eslint-disable */
    get fileName() {
        // This getter voilates the rule no-getter-contains-more-than-return-statement since it is referenced in the template html
        const file = this.files && this.files[0];
        if (file) {
            return file.name;
        }
        return undefined;
    }
    /* eslint-enable */

    // No longer voilating the rule no-getter-contains-more-than-return-statement
    get fileName1() {
        const file = this.files && this.files[0];
        if (file) {
            return file.name;
        }
        return undefined;
    }

    // No longer voilating the rule no-getter-contains-more-than-return-statement
    get fileName2() {
        const file = this.files && this.files[0];
        if (file) {
            return file.name;
        }
        return undefined;
    }

    // No longer voilating the rule no-getter-contains-more-than-return-statement
    get fileName3() {
        const file = this.files && this.files[0];
        if (file) {
            return file.name;
        }
        return undefined;
    }

    // prettier-ignore
    // No longer voilating the rule no-getter-contains-more-than-return-statement
    get fileName4() { 
        const file = this.files && this.files[0];
        if (file) {
            return file.name;
        }
        return undefined;
    }

    // prettier-ignore
    get fileName5() {
        const file = this.files && this.files[0];
        if (file) {
            return file.name;
        }
        return undefined;
    }

    handleInputChange(event) {
        this.files = event.detail.files;
        this.titleValue = this.fileName;
    }

    handleTitleInputChange(event) {
        this.titleValue = event.detail.value;
    }

    handleDescriptionInputChange(event) {
        this.descriptionValue = event.detail.value;
    }

    resetInputs() {
        this.files = [];
        this.titleValue = '';
        this.descriptionValue = '';
        this.errorMessage = '';
    }

    // Handle the user uploading a file
    async handleUploadClick() {
        if (this.uploadingFile) {
            return;
        }

        const file = this.files && this.files[0];
        if (!file) {
            return;
        }

        try {
            this.uploadingFile = true;

            // Create a ContentDocumentLink (CDL) to associate the uploaded file
            // to the Files Related List of a record, like a Work Order.
            const contentDocumentAndVersion = await unstable_createContentDocumentAndVersion({
                title: this.titleValue,
                description: this.descriptionValue,
                fileData: file
            });

            if (this.recordId) {
                const contentDocumentId = contentDocumentAndVersion.contentDocument.id;
                await this.createCdl(this.recordId, contentDocumentId);
            }
            this.resetInputs();
        } catch (error) {
            console.error(error);
            this.errorMessage = error;
        } finally {
            this.uploadingFile = false;
        }
    }

    async createCdl(recordId, contentDocumentId) {
        return createRecord({
            apiName: 'ContentDocumentLink',
            fields: {
                LinkedEntityId: recordId,
                ContentDocumentId: contentDocumentId,
                ShareType: 'V'
            }
        })
            .then(() => {
                this.dispatchEvent(
                    new ShowToastEvent({
                        title: 'Success',
                        message: 'File attached',
                        variant: 'success'
                    })
                );
            })
            .catch((e) => {
                this.dispatchEvent(
                    new ShowToastEvent({
                        title: 'Error uploading file',
                        message: e.body.message,
                        variant: 'error'
                    })
                );
            });
    }
}