From fb7080f82d51aa7e2e86041a50966d9e74d1c595 Mon Sep 17 00:00:00 2001
From: Sosuke Suzuki <aosukeke@gmail.com>
Date: Sat, 30 Oct 2021 20:56:12 +0900
Subject: [PATCH] Handle TypeScript 4.5 new file extensions `.mts` and `.cts`
 (#11721)

* Handle .mts and .cts

* Update integration tests

* Add changelog
---
 changelog_unreleased/typescript/11721.md           |  7 +++++++
 src/language-js/index.js                           | 14 +++++++++-----
 .../__tests__/__snapshots__/support-info.js.snap   |  2 +-
 3 files changed, 17 insertions(+), 6 deletions(-)
 create mode 100644 changelog_unreleased/typescript/11721.md

diff --git a/changelog_unreleased/typescript/11721.md b/changelog_unreleased/typescript/11721.md
new file mode 100644
index 000000000..12be34ed1
--- /dev/null
+++ b/changelog_unreleased/typescript/11721.md
@@ -0,0 +1,7 @@
+#### Support TypeScript 4.5 (#11721 by @sosukesuzuki)
+
+Support new TypeScript 4.5 features.
+
+##### Handle `.mts` and `.cts`
+
+Handle new file extensions `.mts` and `.cts`.
diff --git a/src/language-js/index.js b/src/language-js/index.js
index 9df41d132..ad2c2f0d2 100644
--- a/src/language-js/index.js
+++ b/src/language-js/index.js
@@ -67,11 +67,15 @@ const languages = [
     codemirrorMimeType: "text/jsx",
     color: undefined,
   })),
-  createLanguage(require("linguist-languages/data/TypeScript.json"), () => ({
-    since: "1.4.0",
-    parsers: ["typescript", "babel-ts"],
-    vscodeLanguageIds: ["typescript"],
-  })),
+  createLanguage(
+    require("linguist-languages/data/TypeScript.json"),
+    (data) => ({
+      since: "1.4.0",
+      parsers: ["typescript", "babel-ts"],
+      vscodeLanguageIds: ["typescript"],
+      extensions: [...data.extensions, ".mts", ".cts"],
+    })
+  ),
   createLanguage(require("linguist-languages/data/TSX.json"), () => ({
     since: "1.4.0",
     parsers: ["typescript", "babel-ts"],
diff --git a/tests/integration/__tests__/__snapshots__/support-info.js.snap b/tests/integration/__tests__/__snapshots__/support-info.js.snap
index 6296347e5..0245e7203 100644
--- a/tests/integration/__tests__/__snapshots__/support-info.js.snap
+++ b/tests/integration/__tests__/__snapshots__/support-info.js.snap
@@ -394,7 +394,7 @@ exports[`CLI --support-info (stdout) 1`] = `
       \\"codemirrorMimeType\\": \\"application/typescript\\",
       \\"codemirrorMode\\": \\"javascript\\",
       \\"color\\": \\"#2b7489\\",
-      \\"extensions\\": [\\".ts\\"],
+      \\"extensions\\": [\\".ts\\", \\".mts\\", \\".cts\\"],
       \\"interpreters\\": [\\"deno\\", \\"ts-node\\"],
       \\"linguistLanguageId\\": 378,
       \\"name\\": \\"TypeScript\\",