Fix lint

Author: Tyriar

src/extension.ts

@@ -16,7 +16,7 @@ export function activate(context: vscode.ExtensionContext): void {
     vscode.commands.registerCommand('sortLines.sortLinesShuffle', sortLines.sortShuffle),
     vscode.commands.registerCommand('sortLines.removeDuplicateLines', sortLines.removeDuplicateLines),
     vscode.commands.registerCommand('sortLines.keepOnlyDuplicateLines', sortLines.keepOnlyDuplicateLines),
-    vscode.commands.registerCommand('sortLines.keepOnlyNotDuplicateLines', sortLines.keepOnlyNotDuplicateLines),
+    vscode.commands.registerCommand('sortLines.keepOnlyNotDuplicateLines', sortLines.keepOnlyNotDuplicateLines)
   ];
 
   commands.forEach(command => context.subscriptions.push(command));

src/sort-lines.ts

@@ -61,7 +61,7 @@ function keepOnlyDuplicates(lines: string[]): string[] {
 }
 
 function keepOnlyNotDuplicates(lines: string[]): string[] {
-  return Array.from(new Set(lines.filter((element, index, array) => (array.lastIndexOf(element) == array.indexOf(element)))));
+  return Array.from(new Set(lines.filter((element, index, array) => (array.lastIndexOf(element) === array.indexOf(element)))));
 }
 
 function removeBlanks(lines: string[]): void {