Switch to accessibility insights's version of these tools (#603)

* Switch to accessibility insights's version of these tools

* auto-add files meeting strict checks

strict-null-checks/import-finder.js

@@ -0,0 +1,34 @@
+// Copyright (c) Microsoft Corporation. All rights reserved.
+// Licensed under the MIT License.
+
+// @ts-check
+const fs = require("fs");
+const path = require("path");
+const ts = require("typescript");
+
+const imports = new Map();
+const getMemoizedImportsForFile = (file, srcRoot) => {
+  if (imports.has(file)) {
+    return imports.get(file);
+  }
+  const importList = getImportsForFile(file, srcRoot);
+  imports.set(file, importList);
+  return importList;
+};
+
+function getImportsForFile(parent, srcRoot) {
+  return ts
+    .preProcessFile(fs.readFileSync(parent).toString())
+    .importedFiles.map(({ fileName }) => fileName)
+    .filter((base) => /\//.test(base)) // remove node modules (the import must contain '/')
+    .map((base) => (/(^\.\/)|(^\.\.\/)/.test(base) ? path.join(path.dirname(parent), base) : path.join(srcRoot, base)))
+    .map((base) => (fs.existsSync(base) ? path.join(base, "index") : base))
+    .map((base) => base.replace(/\\/g, "/"))
+    .map((base) => ["ts", "tsx", "d.ts", "js", "jsx"].map((ext) => `${base}.${ext}`).find(fs.existsSync))
+    .filter((base) => base && base !== parent);
+}
+
+module.exports = {
+  getImportsForFile,
+  getMemoizedImportsForFile,
+};