86 lines
1.9 KiB
JavaScript
Executable File
86 lines
1.9 KiB
JavaScript
Executable File
/**
|
|
* @fileoverview Rule to flag for-in loops without if statements inside
|
|
* @author Nicholas C. Zakas
|
|
*/
|
|
|
|
"use strict";
|
|
|
|
//------------------------------------------------------------------------------
|
|
// Rule Definition
|
|
//------------------------------------------------------------------------------
|
|
|
|
/** @type {import('../types').Rule.RuleModule} */
|
|
module.exports = {
|
|
meta: {
|
|
type: "suggestion",
|
|
|
|
docs: {
|
|
description: "Require `for-in` loops to include an `if` statement",
|
|
recommended: false,
|
|
url: "https://eslint.org/docs/latest/rules/guard-for-in",
|
|
},
|
|
|
|
schema: [],
|
|
messages: {
|
|
wrap: "The body of a for-in should be wrapped in an if statement to filter unwanted properties from the prototype.",
|
|
},
|
|
},
|
|
|
|
create(context) {
|
|
return {
|
|
ForInStatement(node) {
|
|
const body = node.body;
|
|
|
|
// empty statement
|
|
if (body.type === "EmptyStatement") {
|
|
return;
|
|
}
|
|
|
|
// if statement
|
|
if (body.type === "IfStatement") {
|
|
return;
|
|
}
|
|
|
|
// empty block
|
|
if (body.type === "BlockStatement" && body.body.length === 0) {
|
|
return;
|
|
}
|
|
|
|
// block with just if statement
|
|
if (
|
|
body.type === "BlockStatement" &&
|
|
body.body.length === 1 &&
|
|
body.body[0].type === "IfStatement"
|
|
) {
|
|
return;
|
|
}
|
|
|
|
// block that starts with if statement
|
|
if (
|
|
body.type === "BlockStatement" &&
|
|
body.body.length >= 1 &&
|
|
body.body[0].type === "IfStatement"
|
|
) {
|
|
const i = body.body[0];
|
|
|
|
// ... whose consequent is a continue
|
|
if (i.consequent.type === "ContinueStatement") {
|
|
return;
|
|
}
|
|
|
|
// ... whose consequent is a block that contains only a continue
|
|
if (
|
|
i.consequent.type === "BlockStatement" &&
|
|
i.consequent.body.length === 1 &&
|
|
i.consequent.body[0].type === "ContinueStatement"
|
|
) {
|
|
return;
|
|
}
|
|
}
|
|
|
|
context.report({ node, messageId: "wrap" });
|
|
},
|
|
};
|
|
},
|
|
};
|