eslint-plugin-sonarjs
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JavaScript
;
/*
* SonarQube JavaScript Plugin
* Copyright (C) SonarSource Sàrl
* mailto:info AT sonarsource DOT com
*
* You can redistribute and/or modify this program under the terms of
* the Sonar Source-Available License Version 1, as published by SonarSource Sàrl.
*
* This program is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.
* See the Sonar Source-Available License for more details.
*
* You should have received a copy of the Sonar Source-Available License
* along with this program; if not, see https://sonarsource.com/license/ssal/
*/
// https://sonarsource.github.io/rspec/#/rspec/S1488
var __createBinding = (this && this.__createBinding) || (Object.create ? (function(o, m, k, k2) {
if (k2 === undefined) k2 = k;
var desc = Object.getOwnPropertyDescriptor(m, k);
if (!desc || ("get" in desc ? !m.__esModule : desc.writable || desc.configurable)) {
desc = { enumerable: true, get: function() { return m[k]; } };
}
Object.defineProperty(o, k2, desc);
}) : (function(o, m, k, k2) {
if (k2 === undefined) k2 = k;
o[k2] = m[k];
}));
var __setModuleDefault = (this && this.__setModuleDefault) || (Object.create ? (function(o, v) {
Object.defineProperty(o, "default", { enumerable: true, value: v });
}) : function(o, v) {
o["default"] = v;
});
var __importStar = (this && this.__importStar) || (function () {
var ownKeys = function(o) {
ownKeys = Object.getOwnPropertyNames || function (o) {
var ar = [];
for (var k in o) if (Object.prototype.hasOwnProperty.call(o, k)) ar[ar.length] = k;
return ar;
};
return ownKeys(o);
};
return function (mod) {
if (mod && mod.__esModule) return mod;
var result = {};
if (mod != null) for (var k = ownKeys(mod), i = 0; i < k.length; i++) if (k[i] !== "default") __createBinding(result, mod, k[i]);
__setModuleDefault(result, mod);
return result;
};
})();
Object.defineProperty(exports, "__esModule", { value: true });
exports.rule = void 0;
const generate_meta_js_1 = require("../helpers/generate-meta.js");
const type_js_1 = require("../helpers/type.js");
const ast_js_1 = require("../helpers/ast.js");
const parser_services_js_1 = require("../helpers/parser-services.js");
const collection_js_1 = require("../helpers/collection.js");
const meta = __importStar(require("./generated-meta.js"));
const typescript_1 = require("typescript");
exports.rule = {
meta: (0, generate_meta_js_1.generateMeta)(meta, {
messages: {
doImmediateAction: 'Immediately {{action}} this expression instead of assigning it to the temporary variable "{{variable}}".',
},
fixable: 'code',
}),
create(context) {
return {
BlockStatement(node) {
processStatements(node, node.body);
},
SwitchCase(node) {
processStatements(node, node.consequent);
},
};
function processStatements(node, statements) {
if (statements.length > 1) {
const lastStatement = (0, collection_js_1.last)(statements);
const returnedIdentifier = getOnlyReturnedVariable(lastStatement);
const lastButOne = statements.at(-2);
const declaredIdentifier = getOnlyDeclaredVariable(lastButOne);
if (returnedIdentifier && declaredIdentifier) {
const sameVariable = getVariables(node, context).find(variable => {
return (variable.references.some(ref => ref.identifier === returnedIdentifier) &&
variable.references.some(ref => ref.identifier === declaredIdentifier.id));
});
const id = lastButOne.declarations[0].id;
if (hasJSDoc(id) || isNamedFunctionExpression(id)) {
// 1) The temporary variable might be due to adding the jsdoc. Skip in this case.
// 2) The temporary variable might be a name of a function, which helps with recognizing in a call stack.
return;
}
// there must be only one "read" - in `return` or `throw`
if (sameVariable?.references.filter(ref => ref.isRead()).length === 1) {
context.report({
messageId: 'doImmediateAction',
data: {
action: lastStatement.type === 'ReturnStatement' ? 'return' : 'throw',
variable: returnedIdentifier.name,
},
node: declaredIdentifier.init,
fix: fixer => fix(fixer, lastStatement, lastButOne, declaredIdentifier.init, returnedIdentifier),
});
}
}
}
}
function fix(fixer, last, lastButOne, expressionToReturn, returnedExpression) {
const expressionText = context.sourceCode.getText(expressionToReturn);
const rangeToRemoveStart = lastButOne.range[0];
const commentsBetweenStatements = context.sourceCode.getCommentsAfter(lastButOne);
const rangeToRemoveEnd = commentsBetweenStatements.length > 0
? commentsBetweenStatements[0].range[0]
: last.range[0];
return [
fixer.removeRange([rangeToRemoveStart, rangeToRemoveEnd]),
fixer.replaceText(returnedExpression, expressionText),
];
}
function hasJSDoc(node) {
const services = context.sourceCode.parserServices;
if (!(0, parser_services_js_1.isRequiredParserServices)(services)) {
return false;
}
return !!(0, typescript_1.getJSDocType)(services.esTreeNodeToTSNodeMap.get(node));
}
function isNamedFunctionExpression(node) {
const services = context.sourceCode.parserServices;
if (!(0, parser_services_js_1.isRequiredParserServices)(services)) {
return false;
}
return (0, type_js_1.isFunction)(node, services);
}
},
};
function getOnlyReturnedVariable(node) {
return (node.type === 'ReturnStatement' || node.type === 'ThrowStatement') &&
node.argument &&
(0, ast_js_1.isIdentifier)(node.argument)
? node.argument
: undefined;
}
function getOnlyDeclaredVariable(node) {
if (node.type === 'VariableDeclaration' && node.declarations.length === 1) {
const { id, init } = node.declarations[0];
if (id.type === 'Identifier' && init && !id.typeAnnotation) {
return { id, init };
}
}
return undefined;
}
function getVariables(node, context) {
const { variableScope, variables: currentScopeVariables } = context.sourceCode.getScope(node);
if (variableScope === context.sourceCode.getScope(node)) {
return currentScopeVariables;
}
else {
return currentScopeVariables.concat(variableScope.variables);
}
}