From dd24440b73c186ea45950650a9e53b4a58cfdd5a Mon Sep 17 00:00:00 2001
From: Saul Ifshin <97627272+saul1310@users.noreply.github.com>
Date: Tue, 26 May 2026 15:28:17 -0700
Subject: [PATCH] test(frontend): cover MIME precedence in non-PDF type
 detection (#6438)

# Description of Changes

<!--
Please provide a summary of the changes, including:

- What was changed
- Why the change was made
- Any challenges encountered

Closes #(issue_number)
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---

## Checklist

### General

- [x] I have read the [Contribution
Guidelines](https://github.com/Stirling-Tools/Stirling-PDF/blob/main/CONTRIBUTING.md)
- [x] I have read the [Stirling-PDF Developer
Guide](https://github.com/Stirling-Tools/Stirling-PDF/blob/main/DeveloperGuide.md)
(if applicable)
- [x] I have read the [How to add new languages to
Stirling-PDF](https://github.com/Stirling-Tools/Stirling-PDF/blob/main/devGuide/HowToAddNewLanguage.md)
(if applicable)
- [x] I have performed a self-review of my own code
- [x] My changes generate no new warnings

### Documentation

- [x] I have updated relevant docs on [Stirling-PDF's doc
repo](https://github.com/Stirling-Tools/Stirling-Tools.github.io/blob/main/docs/)
(if functionality has heavily changed)
- [x] I have read the section [Add New Translation
Tags](https://github.com/Stirling-Tools/Stirling-PDF/blob/main/devGuide/HowToAddNewLanguage.md#add-new-translation-tags)
(for new translation tags only)

### Translations (if applicable)

- [x] I ran
[`scripts/counter_translation.py`](https://github.com/Stirling-Tools/Stirling-PDF/blob/main/docs/counter_translation.md)

### UI Changes (if applicable)

- [x] Screenshots or videos demonstrating the UI changes are attached
(e.g., as comments or direct attachments in the PR)

### Testing (if applicable)

- [x] I have run `task check` to verify linters, typechecks, and tests
pass
- [x] I have tested my changes locally. Refer to the [Testing
Guide](https://github.com/Stirling-Tools/Stirling-PDF/blob/main/DeveloperGuide.md#7-testing)
for more details.
---
 frontend/editor/src/core/utils/fileUtils.test.ts | 15 +++++++++++++++
 1 file changed, 15 insertions(+)

diff --git a/frontend/editor/src/core/utils/fileUtils.test.ts b/frontend/editor/src/core/utils/fileUtils.test.ts
index 8b1a1afd9..fcdb53926 100644
--- a/frontend/editor/src/core/utils/fileUtils.test.ts
+++ b/frontend/editor/src/core/utils/fileUtils.test.ts
@@ -3,6 +3,7 @@ import {
   isPdfFile,
   detectFileExtension,
   formatFileSize,
+  detectNonPdfFileType,
 } from "@app/utils/fileUtils";
 
 describe("fileUtils", () => {
@@ -94,4 +95,18 @@ describe("fileUtils", () => {
       expect(formatFileSize(1024 * 1024 * 1024)).toBe("1 GB");
     });
   });
+
+  describe("detectNonPdfFileType", () => {
+    it("should prioritize MIME type over extension when they conflict", () => {
+      expect(
+        detectNonPdfFileType({
+          name: "financial-summary.pdf",
+          type: "text/csv",
+        }),
+      ).toBe("csv");
+      expect(
+        detectNonPdfFileType({ name: "diagram.png", type: "application/json" }),
+      ).toBe("json");
+    });
+  });
 });