feat: migrate some files to typescript

package.json

@@ -24,7 +24,7 @@
     "node": ">=10"
   },
   "scripts": {
-    "build": "kcd-scripts build --ignore \"**/__tests__/**,**/__node_tests__/**,**/__mocks__/**\" && kcd-scripts build --bundle --no-clean",
+    "build": "kcd-scripts build  --no-ts-defs --ignore \"**/__tests__/**,**/__node_tests__/**,**/__mocks__/**\" && kcd-scripts build --no-ts-defs --bundle --no-clean",
     "lint": "kcd-scripts lint",
     "setup": "npm install && npm run validate -s",
     "test": "kcd-scripts test",
@@ -53,11 +53,14 @@
     "jest-serializer-ansi": "^1.0.3",
     "jest-watch-select-projects": "^2.0.0",
     "jsdom": "^16.4.0",
-    "kcd-scripts": "^7.5.1",
+    "kcd-scripts": "^7.5.3",
     "typescript": "^4.1.2"
   },
   "eslintConfig": {
-    "extends": "./node_modules/kcd-scripts/eslint.js",
+    "extends": [
+      "./node_modules/kcd-scripts/eslint.js",
+      "plugin:import/typescript"
+    ],
     "rules": {
       "import/prefer-default-export": "off",
       "import/no-unassigned-import": "off",

src/config.js → src/config.ts

@@ -1,9 +1,15 @@
+import {Config, ConfigFn} from '../types/config'
 import {prettyDOM} from './pretty-dom'
 
+type Callback<T> = () => T
+interface InternalConfig extends Config {
+  _disableExpensiveErrorDiagnostics: boolean
+}
+
 // It would be cleaner for this to live inside './queries', but
 // other parts of the code assume that all exports from
 // './queries' are query functions.
-let config = {
+let config: InternalConfig = {
   testIdAttribute: 'data-testid',
   asyncUtilTimeout: 1000,
   // this is to support React's async `act` function.
@@ -36,7 +42,9 @@ let config = {
 }
 
 export const DEFAULT_IGNORE_TAGS = 'script, style'
-export function runWithExpensiveErrorDiagnosticsDisabled(callback) {
+export function runWithExpensiveErrorDiagnosticsDisabled<T>(
+  callback: Callback<T>,
+) {
   try {
     config._disableExpensiveErrorDiagnostics = true
     return callback()
@@ -45,7 +53,7 @@ export function runWithExpensiveErrorDiagnosticsDisabled(callback) {
   }
 }
 
-export function configure(newConfig) {
+export function configure(newConfig: Partial<Config> | ConfigFn) {
   if (typeof newConfig === 'function') {
     // Pass the existing config out to the provided function
     // and accept a delta in return

src/events.js

@@ -71,12 +71,15 @@ function createEvent(
       /* istanbul ignore if  */
       if (typeof window.DataTransfer === 'function') {
         Object.defineProperty(event, dataTransferKey, {
-          value: Object
-            .getOwnPropertyNames(dataTransferValue)
-            .reduce((acc, propName) => {
-              Object.defineProperty(acc, propName, {value: dataTransferValue[propName]});
-              return acc;
-            }, new window.DataTransfer())
+          value: Object.getOwnPropertyNames(dataTransferValue).reduce(
+            (acc, propName) => {
+              Object.defineProperty(acc, propName, {
+                value: dataTransferValue[propName],
+              })
+              return acc
+            },
+            new window.DataTransfer(),
+          ),
         })
       } else {
         Object.defineProperty(event, dataTransferKey, {

src/label-helpers.js → src/label-helpers.ts

@@ -10,7 +10,9 @@ const labelledNodeNames = [
   'input',
 ]
 
-function getTextContent(node) {
+function getTextContent(
+  node: Node | Element | HTMLInputElement,
+): string | null {
   if (labelledNodeNames.includes(node.nodeName.toLowerCase())) {
     return ''
   }
@@ -22,37 +24,43 @@ function getTextContent(node) {
     .join('')
 }
 
-function getLabelContent(node) {
-  let textContent
-  if (node.tagName.toLowerCase() === 'label') {
-    textContent = getTextContent(node)
+function getLabelContent(element: Element): string | null {
+  let textContent: string | null
+  if (element.tagName.toLowerCase() === 'label') {
+    textContent = getTextContent(element)
   } else {
-    textContent = node.value || node.textContent
+    textContent = (element as HTMLInputElement).value || element.textContent
   }
   return textContent
 }
 
 // Based on https://github.com/eps1lon/dom-accessibility-api/pull/352
-function getRealLabels(element) {
-  if (element.labels !== undefined) return element.labels ?? []
+function getRealLabels(element: Element) {
+  // eslint-disable-next-line @typescript-eslint/no-unnecessary-condition -- types are not aware of older browsers that don't implement `labels`
+  if ((element as HTMLInputElement).labels !== undefined) {
+    return (element as HTMLInputElement).labels ?? []
+  }
 
   if (!isLabelable(element)) return []
 
   const labels = element.ownerDocument.querySelectorAll('label')
   return Array.from(labels).filter(label => label.control === element)
 }
 
-function isLabelable(element) {
+function isLabelable(element: Element) {
   return (
-    element.tagName.match(/BUTTON|METER|OUTPUT|PROGRESS|SELECT|TEXTAREA/) ||
+    /BUTTON|METER|OUTPUT|PROGRESS|SELECT|TEXTAREA/.test(element.tagName) ||
     (element.tagName === 'INPUT' && element.getAttribute('type') !== 'hidden')
   )
 }
 
-function getLabels(container, element, {selector = '*'} = {}) {
-  const labelsId = element.getAttribute('aria-labelledby')
-    ? element.getAttribute('aria-labelledby').split(' ')
-    : []
+function getLabels(
+  container: Element,
+  element: Element,
+  {selector = '*'} = {},
+) {
+  const ariaLabelledBy = element.getAttribute('aria-labelledby')
+  const labelsId = ariaLabelledBy ? ariaLabelledBy.split(' ') : []
   return labelsId.length
     ? labelsId.map(labelId => {
         const labellingElement = container.querySelector(`[id="${labelId}"]`)
@@ -67,7 +75,6 @@ function getLabels(container, element, {selector = '*'} = {}) {
         const labelledFormControl = Array.from(
           label.querySelectorAll(formControlSelector),
         ).filter(formControlElement => formControlElement.matches(selector))[0]
-
         return {content: textToMatch, formControl: labelledFormControl}
       })
 }

src/matches.js → src/matches.ts

@@ -1,19 +1,36 @@
-function assertNotNullOrUndefined(matcher) {
-  if (matcher == null) {
+import {
+  Matcher,
+  NormalizerFn,
+  NormalizerOptions,
+  DefaultNormalizerOptions,
+} from '../types'
+
+type Nullish<T> = T | null | undefined
+
+function assertNotNullOrUndefined<T>(
+  matcher: T,
+): asserts matcher is NonNullable<T> {
+  if (matcher === null || matcher === undefined) {
     throw new Error(
+      // eslint-disable-next-line @typescript-eslint/restrict-template-expressions -- implicitly converting `T` to `string`
       `It looks like ${matcher} was passed instead of a matcher. Did you do something like getByText(${matcher})?`,
     )
   }
 }
 
-function fuzzyMatches(textToMatch, node, matcher, normalizer) {
+function fuzzyMatches(
+  textToMatch: Nullish<string>,
+  node: Nullish<Element>,
+  matcher: Nullish<Matcher>,
+  normalizer: NormalizerFn,
+) {
   if (typeof textToMatch !== 'string') {
     return false
   }
-
   assertNotNullOrUndefined(matcher)
 
   const normalizedText = normalizer(textToMatch)
+
   if (typeof matcher === 'string') {
     return normalizedText.toLowerCase().includes(matcher.toLowerCase())
   } else if (typeof matcher === 'function') {
@@ -23,7 +40,12 @@ function fuzzyMatches(textToMatch, node, matcher, normalizer) {
   }
 }
 
-function matches(textToMatch, node, matcher, normalizer) {
+function matches(
+  textToMatch: Nullish<string>,
+  node: Nullish<Element>,
+  matcher: Nullish<Matcher>,
+  normalizer: NormalizerFn,
+) {
   if (typeof textToMatch !== 'string') {
     return false
   }
@@ -40,7 +62,10 @@ function matches(textToMatch, node, matcher, normalizer) {
   }
 }
 
-function getDefaultNormalizer({trim = true, collapseWhitespace = true} = {}) {
+function getDefaultNormalizer({
+  trim = true,
+  collapseWhitespace = true,
+}: DefaultNormalizerOptions = {}): NormalizerFn {
   return text => {
     let normalizedText = text
     normalizedText = trim ? normalizedText.trim() : normalizedText
@@ -60,7 +85,12 @@ function getDefaultNormalizer({trim = true, collapseWhitespace = true} = {}) {
  * @param {Function|undefined} normalizer The user-specified normalizer
  * @returns {Function} A normalizer
  */
-function makeNormalizer({trim, collapseWhitespace, normalizer}) {
+
+function makeNormalizer({
+  trim,
+  collapseWhitespace,
+  normalizer,
+}: NormalizerOptions) {
   if (normalizer) {
     // User has specified a custom normalizer
     if (

tsconfig.json

@@ -0,0 +1,7 @@
+{
+  "extends": "./node_modules/kcd-scripts/shared-tsconfig.json",
+  "compilerOptions": {
+    "allowJs": true
+  },
+  "include": ["./src", "./types"]
+}

types/config.d.ts

@@ -1,13 +1,15 @@
 export interface Config {
   testIdAttribute: string
+  // eslint-disable-next-line @typescript-eslint/no-explicit-any
   asyncWrapper(cb: (...args: any[]) => any): Promise<any>
+  // eslint-disable-next-line @typescript-eslint/no-explicit-any
   eventWrapper(cb: (...args: any[]) => any): void
   asyncUtilTimeout: number
   computedStyleSupportsPseudoElements: boolean
   defaultHidden: boolean
   showOriginalStackTrace: boolean
   throwSuggestions: boolean
-  getElementError: (message: string, container: HTMLElement) => Error
+  getElementError: (message: string | null, container: Element) => Error
 }
 
 export interface ConfigFn {

types/matches.d.ts

@@ -1,14 +1,23 @@
 import {ARIARole} from 'aria-query'
 
-export type MatcherFunction = (content: string, element: HTMLElement) => boolean
-export type Matcher = MatcherFunction | {}
+type Nullish<T> = T | null | undefined
+
+export type MatcherFunction = (
+  content: string,
+  element: Nullish<Element>,
+) => boolean
+export type Matcher = MatcherFunction | RegExp | string
 
 // Get autocomplete for ARIARole union types, while still supporting another string
 // Ref: https://github.com/microsoft/TypeScript/issues/29729#issuecomment-505826972
 export type ByRoleMatcher = ARIARole | MatcherFunction | {}
 
 export type NormalizerFn = (text: string) => string
 
+export interface NormalizerOptions extends DefaultNormalizerOptions {
+  normalizer?: NormalizerFn
+}
+
 export interface MatcherOptions {
   exact?: boolean
   /** Use normalizer with getDefaultNormalizer instead */

types/tsconfig.json

@@ -1,4 +1,3 @@
 {
-  "extends": "../node_modules/kcd-scripts/shared-tsconfig.json",
-  "include": ["."]
+  "extends": "../tsconfig.json"
 }