Remove react-scripts type reference on eject (#5611)

* Remove react-scripts type reference on eject

* Check for env file

* Check eject for typescript

* Shuffle appTypeDeclarations

* Append internal types on eject

* Ensure lib is published for types

* Adjust comment

* Don't add a bunch of new lines

* File should exist and not be deleted

* Add debug

* Set file explicitly

* Revert "Set file explicitly"

This reverts commit bcd58a36cbd08a71af50b037d8f1fae6c595fb4e.

* Copy file before destroying ourselves

* Revert "Add debug"

This reverts commit 0068ba81c6d79d99788877c9e1b618acd7412dce.

packages/react-scripts/scripts/eject.js

@@ -223,6 +223,33 @@ inquirer
     );
     console.log();
 
+    if (fs.existsSync(paths.appTypeDeclarations)) {
+      try {
+        // Read app declarations file
+        let content = fs.readFileSync(paths.appTypeDeclarations, 'utf8');
+        const ownContent =
+          fs.readFileSync(paths.ownTypeDeclarations, 'utf8').trim() + os.EOL;
+
+        // Remove react-scripts reference since they're getting a copy of the types in their project
+        content =
+          content
+            // Remove react-scripts types
+            .replace(
+              /^\s*\/\/\/\s*<reference\s+types.+?"react-scripts".*\/>.*(?:\n|$)/gm,
+              ''
+            )
+            .trim() + os.EOL;
+
+        fs.writeFileSync(
+          paths.appTypeDeclarations,
+          (ownContent + os.EOL + content).trim() + os.EOL
+        );
+      } catch (e) {
+        // It's not essential that this succeeds, the TypeScript user should
+        // be able to re-create these types with ease.
+      }
+    }
+
     // "Don't destroy what isn't ours"
     if (ownPath.indexOf(appPath) === 0) {
       try {