fix: add TS types for Jest custom matchers

Author: mmmurray

.gitignore

@@ -2,5 +2,6 @@
 coverage
 lib
 node_modules
+tsconfig.build.json
 tsconfig.json
 yarn-error.log

package.json

@@ -24,6 +24,7 @@
     "jest": "mmm jest",
     "release": "mmm release",
     "test": "mmm test",
+    "test:compile": "mmm test:compile",
     "test:coverage": "mmm test:coverage",
     "test:lint": "mmm test:lint"
   },
@@ -41,6 +42,7 @@
     "@emotion/core": "^10.0.17",
     "@emotion/styled": "^10.0.17",
     "@types/fs-extra": "^8.0.0",
+    "@types/jest-image-snapshot": "^2.8.0",
     "@types/pretty": "^2.0.0",
     "@types/puppeteer": "^1.19.1",
     "@types/yamljs": "^0.2.30",

src/extend-expect.ts

@@ -1,12 +1,23 @@
-// @ts-ignore
-import { toMatchImageSnapshot as toMatchImageSnapshotBase } from 'jest-image-snapshot'
-// @ts-ignore
+import {
+  MatchImageSnapshotOptions,
+  toMatchImageSnapshot as toMatchImageSnapshotBase,
+} from 'jest-image-snapshot'
 import { toMatchSnapshot } from 'jest-snapshot'
 import { a11ySnapshot, domSnapshot, imageSnapshot } from '.'
 import ComponentElement from './types/component-element'
 
+declare global {
+  // eslint-disable-next-line @typescript-eslint/no-namespace
+  namespace jest {
+    interface Matchers<R> {
+      toMatchA11ySnapshot(): R
+      toMatchDomSnapshot(): R
+      toMatchImageSnapshot(options: MatchImageSnapshotOptions): R
+    }
+  }
+}
+
 const extendExpect = () => {
-  // @ts-ignore
   expect.extend({
     async toMatchA11ySnapshot(received: ComponentElement) {
       return toMatchSnapshot.call(
@@ -17,7 +28,6 @@ const extendExpect = () => {
     },
   })
 
-  // @ts-ignore
   expect.extend({
     async toMatchDomSnapshot(received: ComponentElement) {
       return toMatchSnapshot.call(
@@ -28,10 +38,12 @@ const extendExpect = () => {
     },
   })
 
-  // @ts-ignore
   expect.extend({
-    async toMatchImageSnapshot(received: ComponentElement, options: any) {
-      return toMatchImageSnapshotBase.call(
+    async toMatchImageSnapshot(
+      received: ComponentElement,
+      options: MatchImageSnapshotOptions,
+    ) {
+      return (toMatchImageSnapshotBase as any).call(
         this as any,
         await imageSnapshot(received),
         options,

yarn.lock

@@ -1592,7 +1592,14 @@
   resolved "https://registry.yarnpkg.com/@types/jest-diff/-/jest-diff-20.0.1.tgz#35cc15b9c4f30a18ef21852e255fdb02f6d59b89"
   integrity sha512-yALhelO3i0hqZwhjtcr6dYyaLoCHbAMshwtj6cGxTvHZAKXHsYGdff6E8EPw3xLKY0ELUTQ69Q1rQiJENnccMA==
 
-"@types/jest@24.0.18":
+"@types/jest-image-snapshot@^2.8.0":
+  version "2.8.0"
+  resolved "https://registry.yarnpkg.com/@types/jest-image-snapshot/-/jest-image-snapshot-2.8.0.tgz#2f8ed2b23c1b9a8ead32a2f3ee0ef672e5fd01dd"
+  integrity sha512-CsE6PLYGa7hmM8ut1gzkW7iDxrW2xwSv3yJJf2dejwvF7cIPtzHPLpQWO29H4xnzIaLyEB09MiVnYS/LoYpfzw==
+  dependencies:
+    "@types/jest" "*"
+
+"@types/jest@*", "@types/jest@24.0.18":
   version "24.0.18"
   resolved "https://registry.yarnpkg.com/@types/jest/-/jest-24.0.18.tgz#9c7858d450c59e2164a8a9df0905fc5091944498"
   integrity sha512-jcDDXdjTcrQzdN06+TSVsPPqxvsZA/5QkYfIZlq1JMw7FdP5AZylbOc+6B/cuDurctRe+MziUMtQ3xQdrbjqyQ==