2025-04-19 23:12:19 -04:00

382 lines
11 KiB
JavaScript

/**
* @fileoverview Comma style - enforces comma styles of two types: last and first
* @author Vignesh Anand aka vegetableman
* @deprecated in ESLint v8.53.0
*/
'use strict';
const astUtils = require('./utils/ast-utils');
//------------------------------------------------------------------------------
// Rule Definition
//------------------------------------------------------------------------------
/** @type {import('../types').Rule.RuleModule} */
module.exports = {
meta: {
deprecated: {
message: 'Formatting rules are being moved out of ESLint core.',
url: 'https://eslint.org/blog/2023/10/deprecating-formatting-rules/',
deprecatedSince: '8.53.0',
availableUntil: '10.0.0',
replacedBy: [
{
message:
'ESLint Stylistic now maintains deprecated stylistic core rules.',
url: 'https://eslint.style/guide/migration',
plugin: {
name: '@stylistic/eslint-plugin-js',
url: 'https://eslint.style/packages/js',
},
rule: {
name: 'comma-style',
url: 'https://eslint.style/rules/js/comma-style',
},
},
],
},
type: 'layout',
docs: {
description: 'Enforce consistent comma style',
recommended: false,
url: 'https://eslint.org/docs/latest/rules/comma-style',
},
fixable: 'code',
schema: [
{
enum: ['first', 'last'],
},
{
type: 'object',
properties: {
exceptions: {
type: 'object',
additionalProperties: {
type: 'boolean',
},
},
},
additionalProperties: false,
},
],
messages: {
unexpectedLineBeforeAndAfterComma:
"Bad line breaking before and after ','.",
expectedCommaFirst: "',' should be placed first.",
expectedCommaLast: "',' should be placed last.",
},
},
create(context) {
const style = context.options[0] || 'last',
sourceCode = context.sourceCode;
const exceptions = {
ArrayPattern: true,
ArrowFunctionExpression: true,
CallExpression: true,
FunctionDeclaration: true,
FunctionExpression: true,
ImportDeclaration: true,
ObjectPattern: true,
NewExpression: true,
};
if (
context.options.length === 2 &&
Object.hasOwn(context.options[1], 'exceptions')
) {
const keys = Object.keys(context.options[1].exceptions);
for (let i = 0; i < keys.length; i++) {
exceptions[keys[i]] = context.options[1].exceptions[keys[i]];
}
}
//--------------------------------------------------------------------------
// Helpers
//--------------------------------------------------------------------------
/**
* Modified text based on the style
* @param {string} styleType Style type
* @param {string} text Source code text
* @returns {string} modified text
* @private
*/
function getReplacedText(styleType, text) {
switch (styleType) {
case 'between':
return `,${text.replace(astUtils.LINEBREAK_MATCHER, '')}`;
case 'first':
return `${text},`;
case 'last':
return `,${text}`;
default:
return '';
}
}
/**
* Determines the fixer function for a given style.
* @param {string} styleType comma style
* @param {ASTNode} previousItemToken The token to check.
* @param {ASTNode} commaToken The token to check.
* @param {ASTNode} currentItemToken The token to check.
* @returns {Function} Fixer function
* @private
*/
function getFixerFunction(
styleType,
previousItemToken,
commaToken,
currentItemToken
) {
const text =
sourceCode.text.slice(previousItemToken.range[1], commaToken.range[0]) +
sourceCode.text.slice(commaToken.range[1], currentItemToken.range[0]);
const range = [previousItemToken.range[1], currentItemToken.range[0]];
return function (fixer) {
return fixer.replaceTextRange(range, getReplacedText(styleType, text));
};
}
/**
* Validates the spacing around single items in lists.
* @param {Token} previousItemToken The last token from the previous item.
* @param {Token} commaToken The token representing the comma.
* @param {Token} currentItemToken The first token of the current item.
* @param {Token} reportItem The item to use when reporting an error.
* @returns {void}
* @private
*/
function validateCommaItemSpacing(
previousItemToken,
commaToken,
currentItemToken,
reportItem
) {
// if single line
if (
astUtils.isTokenOnSameLine(commaToken, currentItemToken) &&
astUtils.isTokenOnSameLine(previousItemToken, commaToken)
) {
// do nothing.
} else if (
!astUtils.isTokenOnSameLine(commaToken, currentItemToken) &&
!astUtils.isTokenOnSameLine(previousItemToken, commaToken)
) {
const comment = sourceCode.getCommentsAfter(commaToken)[0];
const styleType =
(
comment &&
comment.type === 'Block' &&
astUtils.isTokenOnSameLine(commaToken, comment)
) ?
style
: 'between';
// lone comma
context.report({
node: reportItem,
loc: commaToken.loc,
messageId: 'unexpectedLineBeforeAndAfterComma',
fix: getFixerFunction(
styleType,
previousItemToken,
commaToken,
currentItemToken
),
});
} else if (
style === 'first' &&
!astUtils.isTokenOnSameLine(commaToken, currentItemToken)
) {
context.report({
node: reportItem,
loc: commaToken.loc,
messageId: 'expectedCommaFirst',
fix: getFixerFunction(
style,
previousItemToken,
commaToken,
currentItemToken
),
});
} else if (
style === 'last' &&
astUtils.isTokenOnSameLine(commaToken, currentItemToken)
) {
context.report({
node: reportItem,
loc: commaToken.loc,
messageId: 'expectedCommaLast',
fix: getFixerFunction(
style,
previousItemToken,
commaToken,
currentItemToken
),
});
}
}
/**
* Checks the comma placement with regards to a declaration/property/element
* @param {ASTNode} node The binary expression node to check
* @param {string} property The property of the node containing child nodes.
* @private
* @returns {void}
*/
function validateComma(node, property) {
const items = node[property],
arrayLiteral =
node.type === 'ArrayExpression' || node.type === 'ArrayPattern';
if (items.length > 1 || arrayLiteral) {
// seed as opening [
let previousItemToken = sourceCode.getFirstToken(node);
items.forEach((item) => {
const commaToken =
item ? sourceCode.getTokenBefore(item) : previousItemToken,
currentItemToken =
item ?
sourceCode.getFirstToken(item)
: sourceCode.getTokenAfter(commaToken),
reportItem = item || currentItemToken;
/*
* This works by comparing three token locations:
* - previousItemToken is the last token of the previous item
* - commaToken is the location of the comma before the current item
* - currentItemToken is the first token of the current item
*
* These values get switched around if item is undefined.
* previousItemToken will refer to the last token not belonging
* to the current item, which could be a comma or an opening
* square bracket. currentItemToken could be a comma.
*
* All comparisons are done based on these tokens directly, so
* they are always valid regardless of an undefined item.
*/
if (astUtils.isCommaToken(commaToken)) {
validateCommaItemSpacing(
previousItemToken,
commaToken,
currentItemToken,
reportItem
);
}
if (item) {
const tokenAfterItem = sourceCode.getTokenAfter(
item,
astUtils.isNotClosingParenToken
);
previousItemToken =
tokenAfterItem ?
sourceCode.getTokenBefore(tokenAfterItem)
: sourceCode.ast.tokens.at(-1);
} else {
previousItemToken = currentItemToken;
}
});
/*
* Special case for array literals that have empty last items, such
* as [ 1, 2, ]. These arrays only have two items show up in the
* AST, so we need to look at the token to verify that there's no
* dangling comma.
*/
if (arrayLiteral) {
const lastToken = sourceCode.getLastToken(node),
nextToLastToken = sourceCode.getTokenBefore(lastToken);
if (astUtils.isCommaToken(nextToLastToken)) {
validateCommaItemSpacing(
sourceCode.getTokenBefore(nextToLastToken),
nextToLastToken,
lastToken,
lastToken
);
}
}
}
}
//--------------------------------------------------------------------------
// Public
//--------------------------------------------------------------------------
const nodes = {};
if (!exceptions.VariableDeclaration) {
nodes.VariableDeclaration = function (node) {
validateComma(node, 'declarations');
};
}
if (!exceptions.ObjectExpression) {
nodes.ObjectExpression = function (node) {
validateComma(node, 'properties');
};
}
if (!exceptions.ObjectPattern) {
nodes.ObjectPattern = function (node) {
validateComma(node, 'properties');
};
}
if (!exceptions.ArrayExpression) {
nodes.ArrayExpression = function (node) {
validateComma(node, 'elements');
};
}
if (!exceptions.ArrayPattern) {
nodes.ArrayPattern = function (node) {
validateComma(node, 'elements');
};
}
if (!exceptions.FunctionDeclaration) {
nodes.FunctionDeclaration = function (node) {
validateComma(node, 'params');
};
}
if (!exceptions.FunctionExpression) {
nodes.FunctionExpression = function (node) {
validateComma(node, 'params');
};
}
if (!exceptions.ArrowFunctionExpression) {
nodes.ArrowFunctionExpression = function (node) {
validateComma(node, 'params');
};
}
if (!exceptions.CallExpression) {
nodes.CallExpression = function (node) {
validateComma(node, 'arguments');
};
}
if (!exceptions.ImportDeclaration) {
nodes.ImportDeclaration = function (node) {
validateComma(node, 'specifiers');
};
}
if (!exceptions.NewExpression) {
nodes.NewExpression = function (node) {
validateComma(node, 'arguments');
};
}
return nodes;
},
};