8058baeaefPR-URL: https://github.com/nodejs/node/pull/12162 Reviewed-By: Teddy Katz <teddy.katz@gmail.com> Reviewed-By: Michaël Zasso <targos@protonmail.com> Reviewed-By: Yuta Hiroto <hello@about-hiroppy.com> Reviewed-By: James M Snell <jasnell@gmail.com> Reviewed-By: Colin Ihrig <cjihrig@gmail.com>
87 lines
2.5 KiB
JavaScript
87 lines
2.5 KiB
JavaScript
/**
|
|
* @fileoverview Rule to enforce declarations in program or function body root.
|
|
* @author Brandon Mills
|
|
*/
|
|
|
|
"use strict";
|
|
|
|
//------------------------------------------------------------------------------
|
|
// Rule Definition
|
|
//------------------------------------------------------------------------------
|
|
|
|
module.exports = {
|
|
meta: {
|
|
docs: {
|
|
description: "disallow variable or `function` declarations in nested blocks",
|
|
category: "Possible Errors",
|
|
recommended: true
|
|
},
|
|
|
|
schema: [
|
|
{
|
|
enum: ["functions", "both"]
|
|
}
|
|
]
|
|
},
|
|
|
|
create(context) {
|
|
|
|
/**
|
|
* Find the nearest Program or Function ancestor node.
|
|
* @returns {Object} Ancestor's type and distance from node.
|
|
*/
|
|
function nearestBody() {
|
|
const ancestors = context.getAncestors();
|
|
let ancestor = ancestors.pop(),
|
|
generation = 1;
|
|
|
|
while (ancestor && ["Program", "FunctionDeclaration",
|
|
"FunctionExpression", "ArrowFunctionExpression"
|
|
].indexOf(ancestor.type) < 0) {
|
|
generation += 1;
|
|
ancestor = ancestors.pop();
|
|
}
|
|
|
|
return {
|
|
|
|
// Type of containing ancestor
|
|
type: ancestor.type,
|
|
|
|
// Separation between ancestor and node
|
|
distance: generation
|
|
};
|
|
}
|
|
|
|
/**
|
|
* Ensure that a given node is at a program or function body's root.
|
|
* @param {ASTNode} node Declaration node to check.
|
|
* @returns {void}
|
|
*/
|
|
function check(node) {
|
|
const body = nearestBody(node),
|
|
valid = ((body.type === "Program" && body.distance === 1) ||
|
|
body.distance === 2);
|
|
|
|
if (!valid) {
|
|
context.report({ node, message: "Move {{type}} declaration to {{body}} root.", data: {
|
|
type: (node.type === "FunctionDeclaration"
|
|
? "function" : "variable"),
|
|
body: (body.type === "Program"
|
|
? "program" : "function body")
|
|
} });
|
|
}
|
|
}
|
|
|
|
return {
|
|
|
|
FunctionDeclaration: check,
|
|
VariableDeclaration(node) {
|
|
if (context.options[0] === "both" && node.kind === "var") {
|
|
check(node);
|
|
}
|
|
}
|
|
|
|
};
|
|
|
|
}
|
|
};
|