From 0e54a1078f20c9bcd867c5ab6697be2a7aaa07c4 Mon Sep 17 00:00:00 2001
From: Eric Mc Sween <5454374+emcsween@users.noreply.github.com>
Date: Wed, 24 Apr 2024 11:09:53 -0400
Subject: [PATCH] Merge pull request #17931 from overleaf/em-invalid-ranges

Throw error when constructing invalid ranges

GitOrigin-RevId: 9451e0f8d35372610d08530048e7ee2ca1ff2052
---
 libraries/overleaf-editor-core/lib/range.js       | 6 ++++++
 libraries/overleaf-editor-core/test/range.test.js | 8 ++++++++
 2 files changed, 14 insertions(+)

diff --git a/libraries/overleaf-editor-core/lib/range.js b/libraries/overleaf-editor-core/lib/range.js
index 3fd83e88f2..4984f129c7 100644
--- a/libraries/overleaf-editor-core/lib/range.js
+++ b/libraries/overleaf-editor-core/lib/range.js
@@ -1,10 +1,16 @@
 // @ts-check
+
+const OError = require('@overleaf/o-error')
+
 class Range {
   /**
    * @param {number} pos
    * @param {number} length
    */
   constructor(pos, length) {
+    if (pos < 0 || length < 0) {
+      throw new OError('Invalid range', { pos, length })
+    }
     /** @readonly */
     this.pos = pos
     /** @readonly */
diff --git a/libraries/overleaf-editor-core/test/range.test.js b/libraries/overleaf-editor-core/test/range.test.js
index b9c6be6fe4..daad8fd6ed 100644
--- a/libraries/overleaf-editor-core/test/range.test.js
+++ b/libraries/overleaf-editor-core/test/range.test.js
@@ -30,6 +30,14 @@ describe('Range', function () {
     expect(range0length.isEmpty()).to.be.true
   })
 
+  it('should not create a range with a negative position', function () {
+    expect(() => new Range(-1, 10)).to.throw
+  })
+
+  it('should not create a range with a negative length', function () {
+    expect(() => new Range(0, -2)).to.throw
+  })
+
   describe('overlaps', function () {
     it('same ranges should overlap', function () {
       const range1 = new Range(1, 3)