/** * @fileoverview Validates JSDoc comments are syntactically correct * @author Nicholas C. Zakas */ "use strict"; //------------------------------------------------------------------------------ // Requirements //------------------------------------------------------------------------------ const doctrine = require("doctrine"); //------------------------------------------------------------------------------ // Rule Definition //------------------------------------------------------------------------------ module.exports = { meta: { docs: { description: "enforce valid JSDoc comments", category: "Possible Errors", recommended: false, url: "https://eslint.org/docs/rules/valid-jsdoc" }, schema: [ { type: "object", properties: { prefer: { type: "object", additionalProperties: { type: "string" } }, preferType: { type: "object", additionalProperties: { type: "string" } }, requireReturn: { type: "boolean" }, requireParamDescription: { type: "boolean" }, requireReturnDescription: { type: "boolean" }, matchDescription: { type: "string" }, requireReturnType: { type: "boolean" } }, additionalProperties: false } ], fixable: "code" }, create(context) { const options = context.options[0] || {}, prefer = options.prefer || {}, sourceCode = context.getSourceCode(), // these both default to true, so you have to explicitly make them false requireReturn = options.requireReturn !== false, requireParamDescription = options.requireParamDescription !== false, requireReturnDescription = options.requireReturnDescription !== false, requireReturnType = options.requireReturnType !== false, preferType = options.preferType || {}, checkPreferType = Object.keys(preferType).length !== 0; //-------------------------------------------------------------------------- // Helpers //-------------------------------------------------------------------------- // Using a stack to store if a function returns or not (handling nested functions) const fns = []; /** * Check if node type is a Class * @param {ASTNode} node node to check. * @returns {boolean} True is its a class * @private */ function isTypeClass(node) { return node.type === "ClassExpression" || node.type === "ClassDeclaration"; } /** * When parsing a new function, store it in our function stack. * @param {ASTNode} node A function node to check. * @returns {void} * @private */ function startFunction(node) { fns.push({ returnPresent: (node.type === "ArrowFunctionExpression" && node.body.type !== "BlockStatement") || isTypeClass(node) }); } /** * Indicate that return has been found in the current function. * @param {ASTNode} node The return node. * @returns {void} * @private */ function addReturn(node) { const functionState = fns[fns.length - 1]; if (functionState && node.argument !== null) { functionState.returnPresent = true; } } /** * Check if return tag type is void or undefined * @param {Object} tag JSDoc tag * @returns {boolean} True if its of type void or undefined * @private */ function isValidReturnType(tag) { return tag.type === null || tag.type.name === "void" || tag.type.type === "UndefinedLiteral"; } /** * Check if type should be validated based on some exceptions * @param {Object} type JSDoc tag * @returns {boolean} True if it can be validated * @private */ function canTypeBeValidated(type) { return type !== "UndefinedLiteral" && // {undefined} as there is no name property available. type !== "NullLiteral" && // {null} type !== "NullableLiteral" && // {?} type !== "FunctionType" && // {function(a)} type !== "AllLiteral"; // {*} } /** * Extract the current and expected type based on the input type object * @param {Object} type JSDoc tag * @returns {{currentType: Doctrine.Type, expectedTypeName: string}} The current type annotation and * the expected name of the annotation * @private */ function getCurrentExpectedTypes(type) { let currentType; if (type.name) { currentType = type; } else if (type.expression) { currentType = type.expression; } return { currentType, expectedTypeName: currentType && preferType[currentType.name] }; } /** * Gets the location of a JSDoc node in a file * @param {Token} jsdocComment The comment that this node is parsed from * @param {{range: number[]}} parsedJsdocNode A tag or other node which was parsed from this comment * @returns {{start: SourceLocation, end: SourceLocation}} The 0-based source location for the tag */ function getAbsoluteRange(jsdocComment, parsedJsdocNode) { return { start: sourceCode.getLocFromIndex(jsdocComment.range[0] + 2 + parsedJsdocNode.range[0]), end: sourceCode.getLocFromIndex(jsdocComment.range[0] + 2 + parsedJsdocNode.range[1]) }; } /** * Validate type for a given JSDoc node * @param {Object} jsdocNode JSDoc node * @param {Object} type JSDoc tag * @returns {void} * @private */ function validateType(jsdocNode, type) { if (!type || !canTypeBeValidated(type.type)) { return; } const typesToCheck = []; let elements = []; switch (type.type) { case "TypeApplication": // {Array.} elements = type.applications[0].type === "UnionType" ? type.applications[0].elements : type.applications; typesToCheck.push(getCurrentExpectedTypes(type)); break; case "RecordType": // {{20:String}} elements = type.fields; break; case "UnionType": // {String|number|Test} case "ArrayType": // {[String, number, Test]} elements = type.elements; break; case "FieldType": // Array.<{count: number, votes: number}> if (type.value) { typesToCheck.push(getCurrentExpectedTypes(type.value)); } break; default: typesToCheck.push(getCurrentExpectedTypes(type)); } elements.forEach(validateType.bind(null, jsdocNode)); typesToCheck.forEach(typeToCheck => { if (typeToCheck.expectedTypeName && typeToCheck.expectedTypeName !== typeToCheck.currentType.name) { context.report({ node: jsdocNode, message: "Use '{{expectedTypeName}}' instead of '{{currentTypeName}}'.", loc: getAbsoluteRange(jsdocNode, typeToCheck.currentType), data: { currentTypeName: typeToCheck.currentType.name, expectedTypeName: typeToCheck.expectedTypeName }, fix(fixer) { return fixer.replaceTextRange( typeToCheck.currentType.range.map(indexInComment => jsdocNode.range[0] + 2 + indexInComment), typeToCheck.expectedTypeName ); } }); } }); } /** * Validate the JSDoc node and output warnings if anything is wrong. * @param {ASTNode} node The AST node to check. * @returns {void} * @private */ function checkJSDoc(node) { const jsdocNode = sourceCode.getJSDocComment(node), functionData = fns.pop(), paramTagsByName = Object.create(null), paramTags = []; let hasReturns = false, returnsTag, hasConstructor = false, isInterface = false, isOverride = false, isAbstract = false; // make sure only to validate JSDoc comments if (jsdocNode) { let jsdoc; try { jsdoc = doctrine.parse(jsdocNode.value, { strict: true, unwrap: true, sloppy: true, range: true }); } catch (ex) { if (/braces/i.test(ex.message)) { context.report({ node: jsdocNode, message: "JSDoc type missing brace." }); } else { context.report({ node: jsdocNode, message: "JSDoc syntax error." }); } return; } jsdoc.tags.forEach(tag => { switch (tag.title.toLowerCase()) { case "param": case "arg": case "argument": paramTags.push(tag); break; case "return": case "returns": hasReturns = true; returnsTag = tag; break; case "constructor": case "class": hasConstructor = true; break; case "override": case "inheritdoc": isOverride = true; break; case "abstract": case "virtual": isAbstract = true; break; case "interface": isInterface = true; break; // no default } // check tag preferences if (prefer.hasOwnProperty(tag.title) && tag.title !== prefer[tag.title]) { const entireTagRange = getAbsoluteRange(jsdocNode, tag); context.report({ node: jsdocNode, message: "Use @{{name}} instead.", loc: { start: entireTagRange.start, end: { line: entireTagRange.start.line, column: entireTagRange.start.column + `@${tag.title}`.length } }, data: { name: prefer[tag.title] }, fix(fixer) { return fixer.replaceTextRange( [ jsdocNode.range[0] + tag.range[0] + 3, jsdocNode.range[0] + tag.range[0] + tag.title.length + 3 ], prefer[tag.title] ); } }); } // validate the types if (checkPreferType && tag.type) { validateType(jsdocNode, tag.type); } }); paramTags.forEach(param => { if (!param.type) { context.report({ node: jsdocNode, message: "Missing JSDoc parameter type for '{{name}}'.", loc: getAbsoluteRange(jsdocNode, param), data: { name: param.name } }); } if (!param.description && requireParamDescription) { context.report({ node: jsdocNode, message: "Missing JSDoc parameter description for '{{name}}'.", loc: getAbsoluteRange(jsdocNode, param), data: { name: param.name } }); } if (paramTagsByName[param.name]) { context.report({ node: jsdocNode, message: "Duplicate JSDoc parameter '{{name}}'.", loc: getAbsoluteRange(jsdocNode, param), data: { name: param.name } }); } else if (param.name.indexOf(".") === -1) { paramTagsByName[param.name] = param; } }); if (hasReturns) { if (!requireReturn && !functionData.returnPresent && (returnsTag.type === null || !isValidReturnType(returnsTag)) && !isAbstract) { context.report({ node: jsdocNode, message: "Unexpected @{{title}} tag; function has no return statement.", loc: getAbsoluteRange(jsdocNode, returnsTag), data: { title: returnsTag.title } }); } else { if (requireReturnType && !returnsTag.type) { context.report({ node: jsdocNode, message: "Missing JSDoc return type." }); } if (!isValidReturnType(returnsTag) && !returnsTag.description && requireReturnDescription) { context.report({ node: jsdocNode, message: "Missing JSDoc return description." }); } } } // check for functions missing @returns if (!isOverride && !hasReturns && !hasConstructor && !isInterface && node.parent.kind !== "get" && node.parent.kind !== "constructor" && node.parent.kind !== "set" && !isTypeClass(node)) { if (requireReturn || functionData.returnPresent) { context.report({ node: jsdocNode, message: "Missing JSDoc @{{returns}} for function.", data: { returns: prefer.returns || "returns" } }); } } // check the parameters const jsdocParamNames = Object.keys(paramTagsByName); if (node.params) { node.params.forEach((param, paramsIndex) => { const bindingParam = param.type === "AssignmentPattern" ? param.left : param; // TODO(nzakas): Figure out logical things to do with destructured, default, rest params if (bindingParam.type === "Identifier") { const name = bindingParam.name; if (jsdocParamNames[paramsIndex] && (name !== jsdocParamNames[paramsIndex])) { context.report({ node: jsdocNode, message: "Expected JSDoc for '{{name}}' but found '{{jsdocName}}'.", loc: getAbsoluteRange(jsdocNode, paramTagsByName[jsdocParamNames[paramsIndex]]), data: { name, jsdocName: jsdocParamNames[paramsIndex] } }); } else if (!paramTagsByName[name] && !isOverride) { context.report({ node: jsdocNode, message: "Missing JSDoc for parameter '{{name}}'.", data: { name } }); } } }); } if (options.matchDescription) { const regex = new RegExp(options.matchDescription); if (!regex.test(jsdoc.description)) { context.report({ node: jsdocNode, message: "JSDoc description does not satisfy the regex pattern." }); } } } } //-------------------------------------------------------------------------- // Public //-------------------------------------------------------------------------- return { ArrowFunctionExpression: startFunction, FunctionExpression: startFunction, FunctionDeclaration: startFunction, ClassExpression: startFunction, ClassDeclaration: startFunction, "ArrowFunctionExpression:exit": checkJSDoc, "FunctionExpression:exit": checkJSDoc, "FunctionDeclaration:exit": checkJSDoc, "ClassExpression:exit": checkJSDoc, "ClassDeclaration:exit": checkJSDoc, ReturnStatement: addReturn }; } };