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How the feature works? / How did you fix the issue?

SonarQube flagged two instances where reverse() was used misleadingly—the method mutates the array and returns it, obscuring whether mutation is intentional.

Changes:

• Line 3253: selectedPiece.reverse().forEach() → [...selectedPiece].reverse().forEach()
• Line 3349: senseNode.monomers.reverse().forEach() → [...senseNode.monomers].reverse().forEach()

The spread syntax creates a shallow copy before reversing, eliminating side effects and clarifying intent.

Example:

// Before: mutates original array
selectedPiece.reverse().forEach((node) => { /* ... */ });

// After: operates on copy
[...selectedPiece].reverse().forEach((node) => { /* ... */ });

Check list

• unit-tests written
• e2e-tests written
• documentation updated
• PR name follows the pattern #1234 – issue name
• branch name doesn't contain '#'
• PR is linked with the issue
• base branch (master or release/xx) is correct
• task status changed to "Code review"
• reviewers are notified about the pull request

Original prompt

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This section details on the original issue you should resolve

<issue_title>Refactor: Array-mutating methods should not be used misleadingly</issue_title>
<issue_description>Problem:
Move this array "reverse" operation to a separate statement or replace it with "toReversed".

Why is this an issue?
In JavaScript, some Array methods do not mutate the existing array that the method was called on, but instead return a new array. Other methods mutate the array, and their return value differs depending on the method.
reverse and sort are mutating methods and, in addition, return the altered version. This rule raises an issue when the return values of these methods are assigned, which could lead maintainers to overlook the fact that the original array has been modified.

const reversed = a.reverse(); // Noncompliant: mutating method, no need to assign return value
const sorted = b.sort(); // Noncompliant: mutating method, no need to assign return value

Remove the assignment, so that the intent of mutating the original array is clear.

a.reverse();
b.sort();

Or use non-mutating alternatives toReversed and toSorted.

const reversed = a.toReversed();
const sorted = b.toSorted();

Alternatively, change a mutating method into a non-mutating alternative using the spread syntax (…​).

const reversed = [...a].reverse();
const sorted = [...b].sort();

Or slice() to create a copy first.

const reversed = a.slice().reverse();
const sorted = b.slice().sort();

Problem locations:
packages/ketcher-core/src/domain/entities/DrawingEntitiesManager.ts:3253
packages/ketcher-core/src/domain/entities/DrawingEntitiesManager.ts:3349</issue_description>

Comments on the Issue (you are @copilot in this section)

• Fixes Refactor: Array-mutating methods should not be used misleadingly #8576

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