summaryrefslogtreecommitdiff
path: root/tools/eslint/lib/rules/no-negated-in-lhs.js
blob: d2c39943722ab64ad43a436b68fe45ab205b2228 (plain)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
/**
 * @fileoverview A rule to disallow negated left operands of the `in` operator
 * @author Michael Ficarra
 * @deprecated in ESLint v3.3.0
 */

"use strict";

//------------------------------------------------------------------------------
// Rule Definition
//------------------------------------------------------------------------------

module.exports = {
    meta: {
        docs: {
            description: "disallow negating the left operand in `in` expressions",
            category: "Possible Errors",
            recommended: true,
            replacedBy: ["no-unsafe-negation"]
        },
        deprecated: true,

        schema: []
    },

    create: function(context) {

        return {

            BinaryExpression: function(node) {
                if (node.operator === "in" && node.left.type === "UnaryExpression" && node.left.operator === "!") {
                    context.report(node, "The 'in' expression's left operand is negated.");
                }
            }
        };

    }
};