Bug Report for three-integer-sum

[gugapc]

Bug Report for https://neetcode.io/problems/three-integer-sum

Please describe the bug below and include any steps to reproduce the bug or screenshots if possible.

---

Description

I'm using Swift to solve the Three Sum problem.

False warning on Submit: variable 'nums' was never mutated despite using let

I found an inconsistency between the Run and Submit environments for the Swift solution to the Three Sum problem.
My submitted solution declares the sorted array as a constant:

func threeSum(_ nums: [Int]) -> [[Int]] {
    let numSorted = nums.sorted()

    var results: [[Int]] = []
    for (i, e) in numSorted.enumerated() {
        if i > 0 && e == numSorted[i - 1] { continue }

        var pointerL = i + 1
        var pointerR = numSorted.count - 1

        while pointerL < pointerR {
            let threeSum = numSorted[i] + numSorted[pointerL] + numSorted[pointerR]

            if threeSum == 0 {
                results.append([numSorted[i], numSorted[pointerL], numSorted[pointerR]])
                pointerL += 1

                while numSorted[pointerL] == numSorted[pointerL - 1] {
                    pointerL += 1
                }
            } else if threeSum > 0 {
                pointerR -= 1
            } else {
                pointerL += 1
            }
        }
    }

    return results
}

When I click Run, my solution compiles and runs successfully. However, when I click Submit, I receive the following warning:

warning: variable 'nums' was never mutated; consider changing to 'let' constant

The warning points to this code:

var nums = nums.sorted()

However, my submitted solution does not contain that code. Instead, I use:

let numSorted = nums.sorted()

It seems the Submit environment is compiling a different or outdated version of my code.

Expected behavior

The Submit environment should compile the exact code that was submitted and report diagnostics that match the submitted source.