336 lines
13 KiB
JavaScript
336 lines
13 KiB
JavaScript
|
/**
|
||
|
|
* @fileoverview Rule to flag dangling underscores in variable declarations.
|
||
|
|
* @author Matt DuVall <http://www.mattduvall.com>
|
||
|
|
*/
|
||
|
|
|
||
|
|
"use strict";
|
||
|
|
|
||
|
|
//------------------------------------------------------------------------------
|
||
|
|
// Rule Definition
|
||
|
|
//------------------------------------------------------------------------------
|
||
|
|
|
||
|
|
/** @type {import('../shared/types').Rule} */
|
||
|
|
module.exports = {
|
||
|
|
meta: {
|
||
|
|
type: "suggestion",
|
||
|
|
|
||
|
|
docs: {
|
||
|
|
description: "Disallow dangling underscores in identifiers",
|
||
|
|
recommended: false,
|
||
|
|
url: "https://eslint.org/docs/latest/rules/no-underscore-dangle"
|
||
|
|
},
|
||
|
|
|
||
|
|
schema: [
|
||
|
|
{
|
||
|
|
type: "object",
|
||
|
|
properties: {
|
||
|
|
allow: {
|
||
|
|
type: "array",
|
||
|
|
items: {
|
||
|
|
type: "string"
|
||
|
|
}
|
||
|
|
},
|
||
|
|
allowAfterThis: {
|
||
|
|
type: "boolean",
|
||
|
|
default: false
|
||
|
|
},
|
||
|
|
allowAfterSuper: {
|
||
|
|
type: "boolean",
|
||
|
|
default: false
|
||
|
|
},
|
||
|
|
allowAfterThisConstructor: {
|
||
|
|
type: "boolean",
|
||
|
|
default: false
|
||
|
|
},
|
||
|
|
enforceInMethodNames: {
|
||
|
|
type: "boolean",
|
||
|
|
default: false
|
||
|
|
},
|
||
|
|
allowFunctionParams: {
|
||
|
|
type: "boolean",
|
||
|
|
default: true
|
||
|
|
},
|
||
|
|
enforceInClassFields: {
|
||
|
|
type: "boolean",
|
||
|
|
default: false
|
||
|
|
},
|
||
|
|
allowInArrayDestructuring: {
|
||
|
|
type: "boolean",
|
||
|
|
default: true
|
||
|
|
},
|
||
|
|
allowInObjectDestructuring: {
|
||
|
|
type: "boolean",
|
||
|
|
default: true
|
||
|
|
}
|
||
|
|
},
|
||
|
|
additionalProperties: false
|
||
|
|
}
|
||
|
|
],
|
||
|
|
|
||
|
|
messages: {
|
||
|
|
unexpectedUnderscore: "Unexpected dangling '_' in '{{identifier}}'."
|
||
|
|
}
|
||
|
|
},
|
||
|
|
|
||
|
|
create(context) {
|
||
|
|
|
||
|
|
const options = context.options[0] || {};
|
||
|
|
const ALLOWED_VARIABLES = options.allow ? options.allow : [];
|
||
|
|
const allowAfterThis = typeof options.allowAfterThis !== "undefined" ? options.allowAfterThis : false;
|
||
|
|
const allowAfterSuper = typeof options.allowAfterSuper !== "undefined" ? options.allowAfterSuper : false;
|
||
|
|
const allowAfterThisConstructor = typeof options.allowAfterThisConstructor !== "undefined" ? options.allowAfterThisConstructor : false;
|
||
|
|
const enforceInMethodNames = typeof options.enforceInMethodNames !== "undefined" ? options.enforceInMethodNames : false;
|
||
|
|
const enforceInClassFields = typeof options.enforceInClassFields !== "undefined" ? options.enforceInClassFields : false;
|
||
|
|
const allowFunctionParams = typeof options.allowFunctionParams !== "undefined" ? options.allowFunctionParams : true;
|
||
|
|
const allowInArrayDestructuring = typeof options.allowInArrayDestructuring !== "undefined" ? options.allowInArrayDestructuring : true;
|
||
|
|
const allowInObjectDestructuring = typeof options.allowInObjectDestructuring !== "undefined" ? options.allowInObjectDestructuring : true;
|
||
|
|
const sourceCode = context.sourceCode;
|
||
|
|
|
||
|
|
//-------------------------------------------------------------------------
|
||
|
|
// Helpers
|
||
|
|
//-------------------------------------------------------------------------
|
||
|
|
|
||
|
|
/**
|
||
|
|
* Check if identifier is present inside the allowed option
|
||
|
|
* @param {string} identifier name of the node
|
||
|
|
* @returns {boolean} true if its is present
|
||
|
|
* @private
|
||
|
|
*/
|
||
|
|
function isAllowed(identifier) {
|
||
|
|
return ALLOWED_VARIABLES.includes(identifier);
|
||
|
|
}
|
||
|
|
|
||
|
|
/**
|
||
|
|
* Check if identifier has a dangling underscore
|
||
|
|
* @param {string} identifier name of the node
|
||
|
|
* @returns {boolean} true if its is present
|
||
|
|
* @private
|
||
|
|
*/
|
||
|
|
function hasDanglingUnderscore(identifier) {
|
||
|
|
const len = identifier.length;
|
||
|
|
|
||
|
|
return identifier !== "_" && (identifier[0] === "_" || identifier[len - 1] === "_");
|
||
|
|
}
|
||
|
|
|
||
|
|
/**
|
||
|
|
* Check if identifier is a special case member expression
|
||
|
|
* @param {string} identifier name of the node
|
||
|
|
* @returns {boolean} true if its is a special case
|
||
|
|
* @private
|
||
|
|
*/
|
||
|
|
function isSpecialCaseIdentifierForMemberExpression(identifier) {
|
||
|
|
return identifier === "__proto__";
|
||
|
|
}
|
||
|
|
|
||
|
|
/**
|
||
|
|
* Check if identifier is a special case variable expression
|
||
|
|
* @param {string} identifier name of the node
|
||
|
|
* @returns {boolean} true if its is a special case
|
||
|
|
* @private
|
||
|
|
*/
|
||
|
|
function isSpecialCaseIdentifierInVariableExpression(identifier) {
|
||
|
|
|
||
|
|
// Checks for the underscore library usage here
|
||
|
|
return identifier === "_";
|
||
|
|
}
|
||
|
|
|
||
|
|
/**
|
||
|
|
* Check if a node is a member reference of this.constructor
|
||
|
|
* @param {ASTNode} node node to evaluate
|
||
|
|
* @returns {boolean} true if it is a reference on this.constructor
|
||
|
|
* @private
|
||
|
|
*/
|
||
|
|
function isThisConstructorReference(node) {
|
||
|
|
return node.object.type === "MemberExpression" &&
|
||
|
|
node.object.property.name === "constructor" &&
|
||
|
|
node.object.object.type === "ThisExpression";
|
||
|
|
}
|
||
|
|
|
||
|
|
/**
|
||
|
|
* Check if function parameter has a dangling underscore.
|
||
|
|
* @param {ASTNode} node function node to evaluate
|
||
|
|
* @returns {void}
|
||
|
|
* @private
|
||
|
|
*/
|
||
|
|
function checkForDanglingUnderscoreInFunctionParameters(node) {
|
||
|
|
if (!allowFunctionParams) {
|
||
|
|
node.params.forEach(param => {
|
||
|
|
const { type } = param;
|
||
|
|
let nodeToCheck;
|
||
|
|
|
||
|
|
if (type === "RestElement") {
|
||
|
|
nodeToCheck = param.argument;
|
||
|
|
} else if (type === "AssignmentPattern") {
|
||
|
|
nodeToCheck = param.left;
|
||
|
|
} else {
|
||
|
|
nodeToCheck = param;
|
||
|
|
}
|
||
|
|
|
||
|
|
if (nodeToCheck.type === "Identifier") {
|
||
|
|
const identifier = nodeToCheck.name;
|
||
|
|
|
||
|
|
if (hasDanglingUnderscore(identifier) && !isAllowed(identifier)) {
|
||
|
|
context.report({
|
||
|
|
node: param,
|
||
|
|
messageId: "unexpectedUnderscore",
|
||
|
|
data: {
|
||
|
|
identifier
|
||
|
|
}
|
||
|
|
});
|
||
|
|
}
|
||
|
|
}
|
||
|
|
});
|
||
|
|
}
|
||
|
|
}
|
||
|
|
|
||
|
|
/**
|
||
|
|
* Check if function has a dangling underscore
|
||
|
|
* @param {ASTNode} node node to evaluate
|
||
|
|
* @returns {void}
|
||
|
|
* @private
|
||
|
|
*/
|
||
|
|
function checkForDanglingUnderscoreInFunction(node) {
|
||
|
|
if (node.type === "FunctionDeclaration" && node.id) {
|
||
|
|
const identifier = node.id.name;
|
||
|
|
|
||
|
|
if (typeof identifier !== "undefined" && hasDanglingUnderscore(identifier) && !isAllowed(identifier)) {
|
||
|
|
context.report({
|
||
|
|
node,
|
||
|
|
messageId: "unexpectedUnderscore",
|
||
|
|
data: {
|
||
|
|
identifier
|
||
|
|
}
|
||
|
|
});
|
||
|
|
}
|
||
|
|
}
|
||
|
|
checkForDanglingUnderscoreInFunctionParameters(node);
|
||
|
|
}
|
||
|
|
|
||
|
|
|
||
|
|
/**
|
||
|
|
* Check if variable expression has a dangling underscore
|
||
|
|
* @param {ASTNode} node node to evaluate
|
||
|
|
* @returns {void}
|
||
|
|
* @private
|
||
|
|
*/
|
||
|
|
function checkForDanglingUnderscoreInVariableExpression(node) {
|
||
|
|
sourceCode.getDeclaredVariables(node).forEach(variable => {
|
||
|
|
const definition = variable.defs.find(def => def.node === node);
|
||
|
|
const identifierNode = definition.name;
|
||
|
|
const identifier = identifierNode.name;
|
||
|
|
let parent = identifierNode.parent;
|
||
|
|
|
||
|
|
while (!["VariableDeclarator", "ArrayPattern", "ObjectPattern"].includes(parent.type)) {
|
||
|
|
parent = parent.parent;
|
||
|
|
}
|
||
|
|
|
||
|
|
if (
|
||
|
|
hasDanglingUnderscore(identifier) &&
|
||
|
|
!isSpecialCaseIdentifierInVariableExpression(identifier) &&
|
||
|
|
!isAllowed(identifier) &&
|
||
|
|
!(allowInArrayDestructuring && parent.type === "ArrayPattern") &&
|
||
|
|
!(allowInObjectDestructuring && parent.type === "ObjectPattern")
|
||
|
|
) {
|
||
|
|
context.report({
|
||
|
|
node,
|
||
|
|
messageId: "unexpectedUnderscore",
|
||
|
|
data: {
|
||
|
|
identifier
|
||
|
|
}
|
||
|
|
});
|
||
|
|
}
|
||
|
|
});
|
||
|
|
}
|
||
|
|
|
||
|
|
/**
|
||
|
|
* Check if member expression has a dangling underscore
|
||
|
|
* @param {ASTNode} node node to evaluate
|
||
|
|
* @returns {void}
|
||
|
|
* @private
|
||
|
|
*/
|
||
|
|
function checkForDanglingUnderscoreInMemberExpression(node) {
|
||
|
|
const identifier = node.property.name,
|
||
|
|
isMemberOfThis = node.object.type === "ThisExpression",
|
||
|
|
isMemberOfSuper = node.object.type === "Super",
|
||
|
|
isMemberOfThisConstructor = isThisConstructorReference(node);
|
||
|
|
|
||
|
|
if (typeof identifier !== "undefined" && hasDanglingUnderscore(identifier) &&
|
||
|
|
!(isMemberOfThis && allowAfterThis) &&
|
||
|
|
!(isMemberOfSuper && allowAfterSuper) &&
|
||
|
|
!(isMemberOfThisConstructor && allowAfterThisConstructor) &&
|
||
|
|
!isSpecialCaseIdentifierForMemberExpression(identifier) && !isAllowed(identifier)) {
|
||
|
|
context.report({
|
||
|
|
node,
|
||
|
|
messageId: "unexpectedUnderscore",
|
||
|
|
data: {
|
||
|
|
identifier
|
||
|
|
}
|
||
|
|
});
|
||
|
|
}
|
||
|
|
}
|
||
|
|
|
||
|
|
/**
|
||
|
|
* Check if method declaration or method property has a dangling underscore
|
||
|
|
* @param {ASTNode} node node to evaluate
|
||
|
|
* @returns {void}
|
||
|
|
* @private
|
||
|
|
*/
|
||
|
|
function checkForDanglingUnderscoreInMethod(node) {
|
||
|
|
const identifier = node.key.name;
|
||
|
|
const isMethod = node.type === "MethodDefinition" || node.type === "Property" && node.method;
|
||
|
|
|
||
|
|
if (typeof identifier !== "undefined" && enforceInMethodNames && isMethod && hasDanglingUnderscore(identifier) && !isAllowed(identifier)) {
|
||
|
|
context.report({
|
||
|
|
node,
|
||
|
|
messageId: "unexpectedUnderscore",
|
||
|
|
data: {
|
||
|
|
identifier: node.key.type === "PrivateIdentifier"
|
||
|
|
? `#${identifier}`
|
||
|
|
: identifier
|
||
|
|
}
|
||
|
|
});
|
||
|
|
}
|
||
|
|
}
|
||
|
|
|
||
|
|
/**
|
||
|
|
* Check if a class field has a dangling underscore
|
||
|
|
* @param {ASTNode} node node to evaluate
|
||
|
|
* @returns {void}
|
||
|
|
* @private
|
||
|
|
*/
|
||
|
|
function checkForDanglingUnderscoreInClassField(node) {
|
||
|
|
const identifier = node.key.name;
|
||
|
|
|
||
|
|
if (typeof identifier !== "undefined" && hasDanglingUnderscore(identifier) &&
|
||
|
|
enforceInClassFields &&
|
||
|
|
!isAllowed(identifier)) {
|
||
|
|
context.report({
|
||
|
|
node,
|
||
|
|
messageId: "unexpectedUnderscore",
|
||
|
|
data: {
|
||
|
|
identifier: node.key.type === "PrivateIdentifier"
|
||
|
|
? `#${identifier}`
|
||
|
|
: identifier
|
||
|
|
}
|
||
|
|
});
|
||
|
|
}
|
||
|
|
}
|
||
|
|
|
||
|
|
//--------------------------------------------------------------------------
|
||
|
|
// Public API
|
||
|
|
//--------------------------------------------------------------------------
|
||
|
|
|
||
|
|
return {
|
||
|
|
FunctionDeclaration: checkForDanglingUnderscoreInFunction,
|
||
|
|
VariableDeclarator: checkForDanglingUnderscoreInVariableExpression,
|
||
|
|
MemberExpression: checkForDanglingUnderscoreInMemberExpression,
|
||
|
|
MethodDefinition: checkForDanglingUnderscoreInMethod,
|
||
|
|
PropertyDefinition: checkForDanglingUnderscoreInClassField,
|
||
|
|
Property: checkForDanglingUnderscoreInMethod,
|
||
|
|
FunctionExpression: checkForDanglingUnderscoreInFunction,
|
||
|
|
ArrowFunctionExpression: checkForDanglingUnderscoreInFunction
|
||
|
|
};
|
||
|
|
|
||
|
|
}
|
||
|
|
};
|