From a3c74d04d623d09579dc2448080ac373e36edf49 Mon Sep 17 00:00:00 2001
From: Prakash Meena <pcmhacker511@gmail.com>
Date: Thu, 17 Sep 2026 04:29:50 +0530
Subject: [PATCH] fix(io): honor CRLF option when saving text files in save()

---
 src/io/files.js       |  8 ++++++--
 test/unit/io/files.js | 33 +++++++++++++++++++++++++++++++++
 2 files changed, 39 insertions(+), 2 deletions(-)

diff --git a/src/io/files.js b/src/io/files.js
index 9a55d6121f..53d9920001 100644
--- a/src/io/files.js
+++ b/src/io/files.js
@@ -1669,13 +1669,13 @@ function files(p5, fn) {
           fn.saveJSON(args[0], args[1], args[2]);
           return;
         case 'txt':
-          fn.saveStrings(args[0], args[1], args[2]);
+          fn.saveStrings(args[0], args[1], args[2], args[3]);
           return;
         // =================================================
         // OPTION 3: decide based on object...
         default:
           if (args[0] instanceof Array) {
-            fn.saveStrings(args[0], args[1], args[2]);
+            fn.saveStrings(args[0], args[1], args[2], args[3]);
           } else if (args[0] instanceof p5.Table) {
             fn.saveTable(args[0], args[1], args[2]);
           } else if (args[0] instanceof p5.Image) {
@@ -1938,6 +1938,10 @@ function files(p5, fn) {
    */
   fn.saveStrings = function (list, filename, extension, isCRLF) {
     // p5._validateParameters('saveStrings', arguments);
+    if (typeof extension === 'boolean') {
+      isCRLF = extension;
+      extension = undefined;
+    }
     const ext = extension || 'txt';
     const pWriter = new p5.PrintWriter(filename, ext);
     for (let item of list) {
diff --git a/test/unit/io/files.js b/test/unit/io/files.js
index 1c30776b8c..33803076d6 100644
--- a/test/unit/io/files.js
+++ b/test/unit/io/files.js
@@ -91,6 +91,17 @@ suite('Files', function () {
       expect(URL.createObjectURL).toHaveBeenCalledWith(saveData);
       assert.equal(mockAnchorElement.download, 'myfile.txt');
     });
+
+    test('should download a file with expected contents with CRLF when extension is omitted', async () => {
+      const strings = ['some', 'words'];
+      mockP5Prototype.saveStrings(strings, 'myfile.txt', true);
+
+      const saveData = new Blob([strings.join('\r\n')]);
+      expect(document.createElement).toHaveBeenCalledTimes(1);
+      expect(mockAnchorElement.click).toHaveBeenCalledTimes(1);
+      expect(URL.createObjectURL).toHaveBeenCalledWith(saveData);
+      assert.equal(mockAnchorElement.download, 'myfile.txt');
+    });
   });
 
   // saveJSON()
@@ -191,6 +202,28 @@ suite('Files', function () {
         assert.equal(mockAnchorElement.download, 'filename.txt');
       });
 
+      test('should download a text file with CRLF when isCRLF is passed as 4th arg', async () => {
+        const myStrings = ['aaa', 'bbb'];
+        mockP5Prototype.save(myStrings, 'filename', 'txt', true);
+
+        const saveData = new Blob([myStrings.join('\r\n')]);
+        expect(document.createElement).toHaveBeenCalledTimes(1);
+        expect(mockAnchorElement.click).toHaveBeenCalledTimes(1);
+        expect(URL.createObjectURL).toHaveBeenCalledWith(saveData);
+        assert.equal(mockAnchorElement.download, 'filename.txt');
+      });
+
+      test('should download a text file with CRLF when isCRLF is passed as 3rd arg with extension in filename', async () => {
+        const myStrings = ['aaa', 'bbb'];
+        mockP5Prototype.save(myStrings, 'filename.txt', true);
+
+        const saveData = new Blob([myStrings.join('\r\n')]);
+        expect(document.createElement).toHaveBeenCalledTimes(1);
+        expect(mockAnchorElement.click).toHaveBeenCalledTimes(1);
+        expect(URL.createObjectURL).toHaveBeenCalledWith(saveData);
+        assert.equal(mockAnchorElement.download, 'filename.txt');
+      });
+
       test('should download a json file', async () => {
         const myObj = { hi: 'hello' };
         mockP5Prototype.save(myObj, 'filename.json');