eslint-plugin-de-morgan/dist/rules/no-negated-disjunction.js

ESLint plugin for transforming negated boolean expressions via De Morgan’s laws

'use strict'
const hasNegationInsideParentheses = require('../utils/has-negation-inside-parentheses.js')
const hasBooleanContext = require('../utils/has-boolean-context.js')
const flattenOperands = require('../utils/flatten-operands.js')
const getNodeContent = require('../utils/get-node-content.js')
const toggleNegation = require('../utils/toggle-negation.js')
const isDisjunction = require('../utils/is-disjunction.js')
const toSingleLine = require('../utils/to-single-line.js')
const joinOperands = require('../utils/join-operands.js')
const isPureGroup = require('../utils/is-pure-group.js')
const isNegated = require('../utils/is-negated.js')
const noNegatedDisjunction = {
  create: context => ({
    UnaryExpression: node => {
      let isNegatedDisjunction =
        isNegated.isNegated(node) && isDisjunction.isDisjunction(node.argument)
      let hasPureOuterGroup = isPureGroup.isPureGroup(node, context)
      let isSafeToFix =
        hasBooleanContext.hasBooleanContext(node) ||
        !hasNegationInsideParentheses.hasNegationInsideParentheses(
          node,
          context,
        )
      if (isNegatedDisjunction && hasPureOuterGroup && isSafeToFix) {
        let originalExpression = getNodeContent.getNodeContent(node, context)
        let toggledOperands = flattenOperands.flattenOperands({
          transformer: toggleNegation.toggleNegation,
          expression: node.argument,
          predicate: isDisjunction.isDisjunction,
          context,
        })
        let shouldWrapInParens = false
        let fixedExpression = joinOperands.joinOperands(
          toggledOperands,
          shouldWrapInParens,
          '&&',
        )
        context.report({
          data: {
            original: toSingleLine.toSingleLine(originalExpression),
            fixed: toSingleLine.toSingleLine(fixedExpression),
          },
          fix: fixer => fixer.replaceText(node, fixedExpression),
          messageId: 'convertNegatedDisjunction',
          node,
        })
      }
    },
  }),
  meta: {
    docs: {
      description:
        'Transforms the negation of a disjunction !(A || B) into the equivalent !A && !B according to De Morgan’s law',
      url: 'https://github.com/azat-io/eslint-plugin-de-morgan/blob/main/docs/no-negated-disjunction.md',
      category: 'Best Practices',
      recommended: true,
    },
    messages: {
      convertNegatedDisjunction:
        'Replace negated disjunction `{{ original }}` with `{{ fixed }}`',
    },
    type: 'suggestion',
    fixable: 'code',
    schema: [],
  },
}
module.exports = noNegatedDisjunction