no-delete-var.js 852 B

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  1. /**
  2. * @fileoverview Rule to flag when deleting variables
  3. * @author Ilya Volodin
  4. */
  5. "use strict";
  6. //------------------------------------------------------------------------------
  7. // Rule Definition
  8. //------------------------------------------------------------------------------
  9. /** @type {import('../types').Rule.RuleModule} */
  10. module.exports = {
  11. meta: {
  12. type: "suggestion",
  13. docs: {
  14. description: "Disallow deleting variables",
  15. recommended: true,
  16. url: "https://eslint.org/docs/latest/rules/no-delete-var",
  17. },
  18. schema: [],
  19. messages: {
  20. unexpected: "Variables should not be deleted.",
  21. },
  22. },
  23. create(context) {
  24. return {
  25. UnaryExpression(node) {
  26. if (
  27. node.operator === "delete" &&
  28. node.argument.type === "Identifier"
  29. ) {
  30. context.report({ node, messageId: "unexpected" });
  31. }
  32. },
  33. };
  34. },
  35. };