From 94951716e65702594ecd5acd9b55b71b8a19b93d Mon Sep 17 00:00:00 2001
From: Colin Rotherham <work@colinr.com>
Date: Tue, 29 Nov 2022 12:31:50 +0000
Subject: [PATCH] Jest transform workaround for ESM-only packages

Enables Babel transform for ESM-only packages (to CommonJS) until Jest supports ESM https://jestjs.io/docs/ecmascript-modules

Babel ignores `node_modules` by default
---
 jest.config.js => jest.config.mjs | 13 +++++++++++--
 1 file changed, 11 insertions(+), 2 deletions(-)
 rename jest.config.js => jest.config.mjs (90%)

diff --git a/jest.config.js b/jest.config.mjs
similarity index 90%
rename from jest.config.js
rename to jest.config.mjs
index e8d7d6c57e..8dbaaf940c 100644
--- a/jest.config.js
+++ b/jest.config.mjs
@@ -14,10 +14,19 @@ const config = {
   // See: https://jestjs.io/docs/ecmascript-modules
   transform: {
     '^.+\\.m?js$': ['babel-jest', { rootMode: 'upward' }]
-  }
+  },
+
+  // Enable Babel transforms for ESM-only node_modules
+  // See: https://jestjs.io/docs/ecmascript-modules
+  transformIgnorePatterns: [
+    `<rootDir>/node_modules/(?!${[
+      'del',
+      'slash'
+    ].join('|')}/)`
+  ]
 }
 
-module.exports = {
+export default {
   collectCoverageFrom: ['./src/**/*.{js,mjs}'],
   projects: [
     {