210 lines
7.4 KiB
JavaScript
210 lines
7.4 KiB
JavaScript
|
/**
|
||
|
* @fileoverview Rule to flag trailing underscores in variable declarations.
|
||
|
* @author Matt DuVall <http://www.mattduvall.com>
|
||
|
*/
|
||
|
|
||
|
"use strict";
|
||
|
|
||
|
//------------------------------------------------------------------------------
|
||
|
// Rule Definition
|
||
|
//------------------------------------------------------------------------------
|
||
|
|
||
|
module.exports = {
|
||
|
meta: {
|
||
|
type: "suggestion",
|
||
|
|
||
|
docs: {
|
||
|
description: "disallow dangling underscores in identifiers",
|
||
|
category: "Stylistic Issues",
|
||
|
recommended: false,
|
||
|
url: "https://eslint.org/docs/rules/no-underscore-dangle"
|
||
|
},
|
||
|
|
||
|
schema: [
|
||
|
{
|
||
|
type: "object",
|
||
|
properties: {
|
||
|
allow: {
|
||
|
type: "array",
|
||
|
items: {
|
||
|
type: "string"
|
||
|
}
|
||
|
},
|
||
|
allowAfterThis: {
|
||
|
type: "boolean",
|
||
|
default: false
|
||
|
},
|
||
|
allowAfterSuper: {
|
||
|
type: "boolean",
|
||
|
default: false
|
||
|
},
|
||
|
enforceInMethodNames: {
|
||
|
type: "boolean",
|
||
|
default: false
|
||
|
}
|
||
|
},
|
||
|
additionalProperties: false
|
||
|
}
|
||
|
]
|
||
|
},
|
||
|
|
||
|
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 enforceInMethodNames = typeof options.enforceInMethodNames !== "undefined" ? options.enforceInMethodNames : false;
|
||
|
|
||
|
//-------------------------------------------------------------------------
|
||
|
// 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.some(ident => ident === identifier);
|
||
|
}
|
||
|
|
||
|
/**
|
||
|
* Check if identifier has a underscore at the end
|
||
|
* @param {ASTNode} identifier node to evaluate
|
||
|
* @returns {boolean} true if its is present
|
||
|
* @private
|
||
|
*/
|
||
|
function hasTrailingUnderscore(identifier) {
|
||
|
const len = identifier.length;
|
||
|
|
||
|
return identifier !== "_" && (identifier[0] === "_" || identifier[len - 1] === "_");
|
||
|
}
|
||
|
|
||
|
/**
|
||
|
* Check if identifier is a special case member expression
|
||
|
* @param {ASTNode} identifier node to evaluate
|
||
|
* @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 {ASTNode} identifier node to evaluate
|
||
|
* @returns {boolean} true if its is a special case
|
||
|
* @private
|
||
|
*/
|
||
|
function isSpecialCaseIdentifierInVariableExpression(identifier) {
|
||
|
|
||
|
// Checks for the underscore library usage here
|
||
|
return identifier === "_";
|
||
|
}
|
||
|
|
||
|
/**
|
||
|
* Check if function has a underscore at the end
|
||
|
* @param {ASTNode} node node to evaluate
|
||
|
* @returns {void}
|
||
|
* @private
|
||
|
*/
|
||
|
function checkForTrailingUnderscoreInFunctionDeclaration(node) {
|
||
|
if (node.id) {
|
||
|
const identifier = node.id.name;
|
||
|
|
||
|
if (typeof identifier !== "undefined" && hasTrailingUnderscore(identifier) && !isAllowed(identifier)) {
|
||
|
context.report({
|
||
|
node,
|
||
|
message: "Unexpected dangling '_' in '{{identifier}}'.",
|
||
|
data: {
|
||
|
identifier
|
||
|
}
|
||
|
});
|
||
|
}
|
||
|
}
|
||
|
}
|
||
|
|
||
|
/**
|
||
|
* Check if variable expression has a underscore at the end
|
||
|
* @param {ASTNode} node node to evaluate
|
||
|
* @returns {void}
|
||
|
* @private
|
||
|
*/
|
||
|
function checkForTrailingUnderscoreInVariableExpression(node) {
|
||
|
const identifier = node.id.name;
|
||
|
|
||
|
if (typeof identifier !== "undefined" && hasTrailingUnderscore(identifier) &&
|
||
|
!isSpecialCaseIdentifierInVariableExpression(identifier) && !isAllowed(identifier)) {
|
||
|
context.report({
|
||
|
node,
|
||
|
message: "Unexpected dangling '_' in '{{identifier}}'.",
|
||
|
data: {
|
||
|
identifier
|
||
|
}
|
||
|
});
|
||
|
}
|
||
|
}
|
||
|
|
||
|
/**
|
||
|
* Check if member expression has a underscore at the end
|
||
|
* @param {ASTNode} node node to evaluate
|
||
|
* @returns {void}
|
||
|
* @private
|
||
|
*/
|
||
|
function checkForTrailingUnderscoreInMemberExpression(node) {
|
||
|
const identifier = node.property.name,
|
||
|
isMemberOfThis = node.object.type === "ThisExpression",
|
||
|
isMemberOfSuper = node.object.type === "Super";
|
||
|
|
||
|
if (typeof identifier !== "undefined" && hasTrailingUnderscore(identifier) &&
|
||
|
!(isMemberOfThis && allowAfterThis) &&
|
||
|
!(isMemberOfSuper && allowAfterSuper) &&
|
||
|
!isSpecialCaseIdentifierForMemberExpression(identifier) && !isAllowed(identifier)) {
|
||
|
context.report({
|
||
|
node,
|
||
|
message: "Unexpected dangling '_' in '{{identifier}}'.",
|
||
|
data: {
|
||
|
identifier
|
||
|
}
|
||
|
});
|
||
|
}
|
||
|
}
|
||
|
|
||
|
/**
|
||
|
* Check if method declaration or method property has a underscore at the end
|
||
|
* @param {ASTNode} node node to evaluate
|
||
|
* @returns {void}
|
||
|
* @private
|
||
|
*/
|
||
|
function checkForTrailingUnderscoreInMethod(node) {
|
||
|
const identifier = node.key.name;
|
||
|
const isMethod = node.type === "MethodDefinition" || node.type === "Property" && node.method;
|
||
|
|
||
|
if (typeof identifier !== "undefined" && enforceInMethodNames && isMethod && hasTrailingUnderscore(identifier)) {
|
||
|
context.report({
|
||
|
node,
|
||
|
message: "Unexpected dangling '_' in '{{identifier}}'.",
|
||
|
data: {
|
||
|
identifier
|
||
|
}
|
||
|
});
|
||
|
}
|
||
|
}
|
||
|
|
||
|
//--------------------------------------------------------------------------
|
||
|
// Public API
|
||
|
//--------------------------------------------------------------------------
|
||
|
|
||
|
return {
|
||
|
FunctionDeclaration: checkForTrailingUnderscoreInFunctionDeclaration,
|
||
|
VariableDeclarator: checkForTrailingUnderscoreInVariableExpression,
|
||
|
MemberExpression: checkForTrailingUnderscoreInMemberExpression,
|
||
|
MethodDefinition: checkForTrailingUnderscoreInMethod,
|
||
|
Property: checkForTrailingUnderscoreInMethod
|
||
|
};
|
||
|
|
||
|
}
|
||
|
};
|