Add missing nil check that causes panic in LSP document-highlight

[ahejlsberg]

Panic occurs when opening a file with cursor positioned in a commented out section at the beginning of the file.

[Copilot]

Pull Request Overview

Fixes a panic in the LSP document-highlight feature that occurs when a cursor is positioned in a commented out section at the beginning of a file. The fix adds a missing nil check to prevent dereferencing a nil pointer.

• Adds nil check for resolvedRef before accessing its fields

[Copilot]

The nil check for resolvedRef should be performed before accessing any of its fields. Consider splitting this into two separate checks for better readability and to avoid potential short-circuit evaluation issues: first check if resolvedRef == nil and return early, then check if resolvedRef.file == nil.

Suggested change

	if resolvedRef == nil || resolvedRef.file == nil {
	return nil
	}
	if resolvedRef == nil {
	return nil
	}
	if resolvedRef.file == nil {
	return nil
	}