From 88adb61fd9b6859e29ce5427695e0ed77bbe0285 Mon Sep 17 00:00:00 2001
From: Patrick McElhaney <pmcelhaney@gmail.com>
Date: Wed, 15 May 2024 16:17:58 -0400
Subject: [PATCH] fix #906 -- transpile imports without JS extension properly

---
 .changeset/tough-horses-switch.md             |  5 +++++
 src/server/convert-js-extensions-to-cjs.ts    |  3 ++-
 .../convert-js-extension-to-cjs.test.ts       | 22 ++++++++++++++-----
 3 files changed, 24 insertions(+), 6 deletions(-)
 create mode 100644 .changeset/tough-horses-switch.md

diff --git a/.changeset/tough-horses-switch.md b/.changeset/tough-horses-switch.md
new file mode 100644
index 00000000..f36918d0
--- /dev/null
+++ b/.changeset/tough-horses-switch.md
@@ -0,0 +1,5 @@
+---
+"counterfact": patch
+---
+
+fixes an issue where imports without a file extension were not transpiled properly
diff --git a/src/server/convert-js-extensions-to-cjs.ts b/src/server/convert-js-extensions-to-cjs.ts
index d0f68497..6697dd72 100644
--- a/src/server/convert-js-extensions-to-cjs.ts
+++ b/src/server/convert-js-extensions-to-cjs.ts
@@ -23,7 +23,8 @@ export function convertFileExtensionsToCjs(code: string) {
       ) {
         // Change the module string from "foo.js" to "foo.cjs"
         node.arguments[0].value = node.arguments[0].value.replace(
-          /\.js$/u,
+          // eslint-disable-next-line prefer-named-capture-group, regexp/no-unused-capturing-group, regexp/prefer-named-capture-group
+          /(\.js|\.ts)?$/u,
           ".cjs",
         );
       }
diff --git a/test/server/convert-js-extension-to-cjs.test.ts b/test/server/convert-js-extension-to-cjs.test.ts
index ad24f9db..241c75a1 100644
--- a/test/server/convert-js-extension-to-cjs.test.ts
+++ b/test/server/convert-js-extension-to-cjs.test.ts
@@ -1,11 +1,23 @@
 import { convertFileExtensionsToCjs } from "../../src/server/convert-js-extensions-to-cjs.js";
 
 describe("convertFileExtensionsToCjs", () => {
-  it("converts a local require", () => {
-    expect(convertFileExtensionsToCjs('require("./foo.js");')).toEqual(
-      'require("./foo.cjs");',
-    );
-  });
+  it.each(["./foo.js", "./foo.ts", "./foo"])(
+    "converts %s a local require",
+    (path) => {
+      expect(convertFileExtensionsToCjs(`require("${path}");`)).toEqual(
+        'require("./foo.cjs");',
+      );
+    },
+  );
+
+  it.each(["../foo.js", "../foo.ts", "../foo"])(
+    "converts %s a local require",
+    (path) => {
+      expect(convertFileExtensionsToCjs(`require("${path}");`)).toEqual(
+        'require("../foo.cjs");',
+      );
+    },
+  );
 
   it("does not convert a non-local require", () => {
     expect(convertFileExtensionsToCjs('require("foo/bar.js");')).toEqual(