Prove that my proposed bugfix works

.yarn/patches/karma-source-map-support-npm-1.4.0-b31519ef26.patch

@@ -0,0 +1,21 @@
+diff --git a/lib/index.js b/lib/index.js
+index 05a8697fa0a271c5a23eae67d2c902ed62bcaff5..0e869f3cbc953324746a70b8f0389c033df572fa 100644
+--- a/lib/index.js
++++ b/lib/index.js
+@@ -1,7 +1,5 @@
+ const path = require('path');
+
+-const smsPath = path.dirname(require.resolve('source-map-support'));
+-
+ const createPattern = function(pattern) {
+   return {pattern: pattern, included: true, served: true, watched: false};
+ };
+@@ -9,7 +7,7 @@ const createPattern = function(pattern) {
+ const init = function(files) {
+   files.unshift(createPattern(path.join(__dirname, 'client.js')));
+   files.unshift(
+-    createPattern(path.join(smsPath, 'browser-source-map-support.js'))
++    createPattern(require.resolve('source-map-support/browser-source-map-support.js'))
+   );
+ };
+

.yarnrc.yml

@@ -0,0 +1,3 @@
+nodeLinker: node-modules
+
+yarnPath: .yarn/releases/yarn-3.2.0.cjs

karma.conf.ts

@@ -0,0 +1,71 @@
+// Karma configuration
+// Generated on Wed Mar 09 2022 22:27:01 GMT-0500 (Eastern Standard Time)
+/// <reference types="node" />
+
+process.env.CHROME_BIN = require('puppeteer').executablePath();
+
+module.exports = function(config) {
+  config.set({
+
+    // base path that will be used to resolve all patterns (eg. files, exclude)
+    basePath: '',
+
+
+    // frameworks to use
+    // available frameworks: https://www.npmjs.com/search?q=keywords:karma-adapter
+    frameworks: ['source-map-support', 'jasmine'],
+
+
+    // list of files / patterns to load in the browser
+    files: [
+    ],
+
+
+    // list of files / patterns to exclude
+    exclude: [
+    ],
+
+
+    // preprocess matching files before serving them to the browser
+    // available preprocessors: https://www.npmjs.com/search?q=keywords:karma-preprocessor
+    preprocessors: {
+    },
+
+
+    // test results reporter to use
+    // possible values: 'dots', 'progress'
+    // available reporters: https://www.npmjs.com/search?q=keywords:karma-reporter
+    reporters: ['progress'],
+
+
+    // web server port
+    port: 9876,
+
+
+    // enable / disable colors in the output (reporters and logs)
+    colors: true,
+
+
+    // level of logging
+    // possible values: config.LOG_DISABLE || config.LOG_ERROR || config.LOG_WARN || config.LOG_INFO || config.LOG_DEBUG
+    logLevel: config.LOG_INFO,
+
+
+    // enable / disable watching file and executing tests whenever any file changes
+    autoWatch: true,
+
+
+    // start these browsers
+    // available browser launchers: https://www.npmjs.com/search?q=keywords:karma-launcher
+    browsers: ['ChromeHeadless'],
+
+
+    // Continuous Integration mode
+    // if true, Karma captures browsers, runs the tests and exits
+    singleRun: false,
+
+    // Concurrency level
+    // how many browser instances should be started simultaneously
+    concurrency: Infinity
+  })
+}

package.json

@@ -1,6 +1,18 @@
 {
   "dependencies": {
+    "@types/node": "^17.0.21",
+    "karma": "^6.3.17",
+    "karma-source-map-support": "^1.4.0",
+    "puppeteer": "^13.5.1",
     "ts-node": "latest",
     "typescript": "latest"
+  },
+  "devDependencies": {
+    "karma-chrome-launcher": "^3.1.1",
+    "karma-jasmine": "^4.0.1"
+  },
+  "packageManager": "[email protected]",
+  "resolutions": {
+    "karma-source-map-support": "patch:karma-source-map-support@npm:1.4.0#.yarn/patches/karma-source-map-support-npm-1.4.0-b31519ef26.patch"
   }
 }