diff --git a/cli/tsc/99_main_compiler.js b/cli/tsc/99_main_compiler.js
index e473004918..bfac52ccea 100644
--- a/cli/tsc/99_main_compiler.js
+++ b/cli/tsc/99_main_compiler.js
@@ -544,6 +544,19 @@ delete Object.prototype.__proto__;
     getGlobalTypingsCacheLocation() {
       return undefined;
     },
+    // @ts-ignore Undocumented method.
+    toPath(fileName) {
+      // @ts-ignore Undocumented function.
+      ts.toPath(
+        fileName,
+        this.getCurrentDirectory(),
+        this.getCanonicalFileName(fileName),
+      );
+    },
+    // @ts-ignore Undocumented method.
+    watchNodeModulesForPackageJsonChanges() {
+      return { close() {} };
+    },
     getSourceFile(
       specifier,
       languageVersion,