/**
* @fileoverview Main ESLint object.
* @author Nicholas C. Zakas
*/
"use strict";
//------------------------------------------------------------------------------
// Requirements
//------------------------------------------------------------------------------
const assert = require("assert"),
EventEmitter = require("events").EventEmitter,
escope = require("escope"),
levn = require("levn"),
blankScriptAST = require("../conf/blank-script.json"),
DEFAULT_PARSER = require("../conf/eslint.json").parser,
replacements = require("../conf/replacements.json"),
CodePathAnalyzer = require("./code-path-analysis/code-path-analyzer"),
ConfigOps = require("./config/config-ops"),
validator = require("./config/config-validator"),
Environments = require("./config/environments"),
CommentEventGenerator = require("./util/comment-event-generator"),
NodeEventGenerator = require("./util/node-event-generator"),
SourceCode = require("./util/source-code"),
Traverser = require("./util/traverser"),
RuleContext = require("./rule-context"),
rules = require("./rules"),
timing = require("./timing"),
pkg = require("../package.json");
//------------------------------------------------------------------------------
// Typedefs
//------------------------------------------------------------------------------
/**
* The result of a parsing operation from parseForESLint()
* @typedef {Object} CustomParseResult
* @property {ASTNode} ast The ESTree AST Program node.
* @property {Object} services An object containing additional services related
* to the parser.
*/
//------------------------------------------------------------------------------
// Helpers
//------------------------------------------------------------------------------
/**
* Parses a list of "name:boolean_value" or/and "name" options divided by comma or
* whitespace.
* @param {string} string The string to parse.
* @param {Comment} comment The comment node which has the string.
* @returns {Object} Result map object of names and boolean values
*/
function parseBooleanConfig(string, comment) {
const items = {};
// Collapse whitespace around `:` and `,` to make parsing easier
string = string.replace(/\s*([:,])\s*/g, "$1");
string.split(/\s|,+/).forEach(name => {
if (!name) {
return;
}
const pos = name.indexOf(":");
let value;
if (pos !== -1) {
value = name.substring(pos + 1, name.length);
name = name.substring(0, pos);
}
items[name] = {
value: (value === "true"),
comment
};
});
return items;
}
/**
* Parses a JSON-like config.
* @param {string} string The string to parse.
* @param {Object} location Start line and column of comments for potential error message.
* @param {Object[]} messages The messages queue for potential error message.
* @returns {Object} Result map object
*/
function parseJsonConfig(string, location, messages) {
let items = {};
// Parses a JSON-like comment by the same way as parsing CLI option.
try {
items = levn.parse("Object", string) || {};
// Some tests say that it should ignore invalid comments such as `/*eslint no-alert:abc*/`.
// Also, commaless notations have invalid severity:
// "no-alert: 2 no-console: 2" --> {"no-alert": "2 no-console: 2"}
// Should ignore that case as well.
if (ConfigOps.isEverySeverityValid(items)) {
return items;
}
} catch (ex) {
// ignore to parse the string by a fallback.
}
// Optionator cannot parse commaless notations.
// But we are supporting that. So this is a fallback for that.
items = {};
string = string.replace(/([a-zA-Z0-9\-/]+):/g, "\"$1\":").replace(/(]|[0-9])\s+(?=")/, "$1,");
try {
items = JSON.parse(`{${string}}`);
} catch (ex) {
messages.push({
ruleId: null,
fatal: true,
severity: 2,
source: null,
message: `Failed to parse JSON from '${string}': ${ex.message}`,
line: location.start.line,
column: location.start.column + 1
});
}
return items;
}
/**
* Parses a config of values separated by comma.
* @param {string} string The string to parse.
* @returns {Object} Result map of values and true values
*/
function parseListConfig(string) {
const items = {};
// Collapse whitespace around ,
string = string.replace(/\s*,\s*/g, ",");
string.split(/,+/).forEach(name => {
name = name.trim();
if (!name) {
return;
}
items[name] = true;
});
return items;
}
/**
* Ensures that variables representing built-in properties of the Global Object,
* and any globals declared by special block comments, are present in the global
* scope.
* @param {ASTNode} program The top node of the AST.
* @param {Scope} globalScope The global scope.
* @param {Object} config The existing configuration data.
* @returns {void}
*/
function addDeclaredGlobals(program, globalScope, config) {
const declaredGlobals = {},
exportedGlobals = {},
explicitGlobals = {},
builtin = Environments.get("builtin");
Object.assign(declaredGlobals, builtin);
Object.keys(config.env).forEach(name => {
if (config.env[name]) {
const env = Environments.get(name),
environmentGlobals = env && env.globals;
if (environmentGlobals) {
Object.assign(declaredGlobals, environmentGlobals);
}
}
});
Object.assign(exportedGlobals, config.exported);
Object.assign(declaredGlobals, config.globals);
Object.assign(explicitGlobals, config.astGlobals);
Object.keys(declaredGlobals).forEach(name => {
let variable = globalScope.set.get(name);
if (!variable) {
variable = new escope.Variable(name, globalScope);
variable.eslintExplicitGlobal = false;
globalScope.variables.push(variable);
globalScope.set.set(name, variable);
}
variable.writeable = declaredGlobals[name];
});
Object.keys(explicitGlobals).forEach(name => {
let variable = globalScope.set.get(name);
if (!variable) {
variable = new escope.Variable(name, globalScope);
variable.eslintExplicitGlobal = true;
variable.eslintExplicitGlobalComment = explicitGlobals[name].comment;
globalScope.variables.push(variable);
globalScope.set.set(name, variable);
}
variable.writeable = explicitGlobals[name].value;
});
// mark all exported variables as such
Object.keys(exportedGlobals).forEach(name => {
const variable = globalScope.set.get(name);
if (variable) {
variable.eslintUsed = true;
}
});
/*
* "through" contains all references which definitions cannot be found.
* Since we augment the global scope using configuration, we need to update
* references and remove the ones that were added by configuration.
*/
globalScope.through = globalScope.through.filter(reference => {
const name = reference.identifier.name;
const variable = globalScope.set.get(name);
if (variable) {
/*
* Links the variable and the reference.
* And this reference is removed from `Scope#through`.
*/
reference.resolved = variable;
variable.references.push(reference);
return false;
}
return true;
});
}
/**
* Add data to reporting configuration to disable reporting for list of rules
* starting from start location
* @param {Object[]} reportingConfig Current reporting configuration
* @param {Object} start Position to start
* @param {string[]} rulesToDisable List of rules
* @returns {void}
*/
function disableReporting(reportingConfig, start, rulesToDisable) {
if (rulesToDisable.length) {
rulesToDisable.forEach(rule => {
reportingConfig.push({
start,
end: null,
rule
});
});
} else {
reportingConfig.push({
start,
end: null,
rule: null
});
}
}
/**
* Add data to reporting configuration to enable reporting for list of rules
* starting from start location
* @param {Object[]} reportingConfig Current reporting configuration
* @param {Object} start Position to start
* @param {string[]} rulesToEnable List of rules
* @returns {void}
*/
function enableReporting(reportingConfig, start, rulesToEnable) {
let i;
if (rulesToEnable.length) {
rulesToEnable.forEach(rule => {
for (i = reportingConfig.length - 1; i >= 0; i--) {
if (!reportingConfig[i].end && reportingConfig[i].rule === rule) {
reportingConfig[i].end = start;
break;
}
}
});
} else {
// find all previous disabled locations if they was started as list of rules
let prevStart;
for (i = reportingConfig.length - 1; i >= 0; i--) {
if (prevStart && prevStart !== reportingConfig[i].start) {
break;
}
if (!reportingConfig[i].end) {
reportingConfig[i].end = start;
prevStart = reportingConfig[i].start;
}
}
}
}
/**
* Parses comments in file to extract file-specific config of rules, globals
* and environments and merges them with global config; also code blocks
* where reporting is disabled or enabled and merges them with reporting config.
* @param {string} filename The file being checked.
* @param {ASTNode} ast The top node of the AST.
* @param {Object} config The existing configuration data.
* @param {Object[]} reportingConfig The existing reporting configuration data.
* @param {Object[]} messages The messages queue.
* @returns {Object} Modified config object
*/
function modifyConfigsFromComments(filename, ast, config, reportingConfig, messages) {
let commentConfig = {
exported: {},
astGlobals: {},
rules: {},
env: {}
};
const commentRules = {};
ast.comments.forEach(comment => {
let value = comment.value.trim();
const match = /^(eslint(-\w+){0,3}|exported|globals?)(\s|$)/.exec(value);
if (match) {
value = value.substring(match.index + match[1].length);
if (comment.type === "Block") {
switch (match[1]) {
case "exported":
Object.assign(commentConfig.exported, parseBooleanConfig(value, comment));
break;
case "globals":
case "global":
Object.assign(commentConfig.astGlobals, parseBooleanConfig(value, comment));
break;
case "eslint-env":
Object.assign(commentConfig.env, parseListConfig(value));
break;
case "eslint-disable":
disableReporting(reportingConfig, comment.loc.start, Object.keys(parseListConfig(value)));
break;
case "eslint-enable":
enableReporting(reportingConfig, comment.loc.start, Object.keys(parseListConfig(value)));
break;
case "eslint": {
const items = parseJsonConfig(value, comment.loc, messages);
Object.keys(items).forEach(name => {
const ruleValue = items[name];
validator.validateRuleOptions(name, ruleValue, `${filename} line ${comment.loc.start.line}`);
commentRules[name] = ruleValue;
});
break;
}
// no default
}
} else { // comment.type === "Line"
if (match[1] === "eslint-disable-line") {
disableReporting(reportingConfig, { line: comment.loc.start.line, column: 0 }, Object.keys(parseListConfig(value)));
enableReporting(reportingConfig, comment.loc.end, Object.keys(parseListConfig(value)));
} else if (match[1] === "eslint-disable-next-line") {
disableReporting(reportingConfig, comment.loc.start, Object.keys(parseListConfig(value)));
enableReporting(reportingConfig, { line: comment.loc.start.line + 2 }, Object.keys(parseListConfig(value)));
}
}
}
});
// apply environment configs
Object.keys(commentConfig.env).forEach(name => {
const env = Environments.get(name);
if (env) {
commentConfig = ConfigOps.merge(commentConfig, env);
}
});
Object.assign(commentConfig.rules, commentRules);
return ConfigOps.merge(config, commentConfig);
}
/**
* Check if message of rule with ruleId should be ignored in location
* @param {Object[]} reportingConfig Collection of ignore records
* @param {string} ruleId Id of rule
* @param {Object} location Location of message
* @returns {boolean} True if message should be ignored, false otherwise
*/
function isDisabledByReportingConfig(reportingConfig, ruleId, location) {
for (let i = 0, c = reportingConfig.length; i < c; i++) {
const ignore = reportingConfig[i];
if ((!ignore.rule || ignore.rule === ruleId) &&
(location.line > ignore.start.line || (location.line === ignore.start.line && location.column >= ignore.start.column)) &&
(!ignore.end || (location.line < ignore.end.line || (location.line === ignore.end.line && location.column <= ignore.end.column)))) {
return true;
}
}
return false;
}
/**
* Normalize ECMAScript version from the initial config
* @param {number} ecmaVersion ECMAScript version from the initial config
* @param {boolean} isModule Whether the source type is module or not
* @returns {number} normalized ECMAScript version
*/
function normalizeEcmaVersion(ecmaVersion, isModule) {
// Need at least ES6 for modules
if (isModule && (!ecmaVersion || ecmaVersion < 6)) {
ecmaVersion = 6;
}
// Calculate ECMAScript edition number from official year version starting with
// ES2015, which corresponds with ES6 (or a difference of 2009).
if (ecmaVersion >= 2015) {
ecmaVersion -= 2009;
}
return ecmaVersion;
}
/**
* Process initial config to make it safe to extend by file comment config
* @param {Object} config Initial config
* @returns {Object} Processed config
*/
function prepareConfig(config) {
config.globals = config.globals || config.global || {};
delete config.global;
const copiedRules = {};
let parserOptions = {};
if (typeof config.rules === "object") {
Object.keys(config.rules).forEach(k => {
const rule = config.rules[k];
if (rule === null) {
throw new Error(`Invalid config for rule '${k}'.`);
}
if (Array.isArray(rule)) {
copiedRules[k] = rule.slice();
} else {
copiedRules[k] = rule;
}
});
}
// merge in environment parserOptions
if (typeof config.env === "object") {
Object.keys(config.env).forEach(envName => {
const env = Environments.get(envName);
if (config.env[envName] && env && env.parserOptions) {
parserOptions = ConfigOps.merge(parserOptions, env.parserOptions);
}
});
}
const preparedConfig = {
rules: copiedRules,
parser: config.parser || DEFAULT_PARSER,
globals: ConfigOps.merge({}, config.globals),
env: ConfigOps.merge({}, config.env || {}),
settings: ConfigOps.merge({}, config.settings || {}),
parserOptions: ConfigOps.merge(parserOptions, config.parserOptions || {})
};
const isModule = preparedConfig.parserOptions.sourceType === "module";
if (isModule) {
if (!preparedConfig.parserOptions.ecmaFeatures) {
preparedConfig.parserOptions.ecmaFeatures = {};
}
// can't have global return inside of modules
preparedConfig.parserOptions.ecmaFeatures.globalReturn = false;
}
preparedConfig.parserOptions.ecmaVersion = normalizeEcmaVersion(preparedConfig.parserOptions.ecmaVersion, isModule);
return preparedConfig;
}
/**
* Provide a stub rule with a given message
* @param {string} message The message to be displayed for the rule
* @returns {Function} Stub rule function
*/
function createStubRule(message) {
/**
* Creates a fake rule object
* @param {Object} context context object for each rule
* @returns {Object} collection of node to listen on
*/
function createRuleModule(context) {
return {
Program(node) {
context.report(node, message);
}
};
}
if (message) {
return createRuleModule;
} else {
throw new Error("No message passed to stub rule");
}
}
/**
* Provide a rule replacement message
* @param {string} ruleId Name of the rule
* @returns {string} Message detailing rule replacement
*/
function getRuleReplacementMessage(ruleId) {
if (ruleId in replacements.rules) {
const newRules = replacements.rules[ruleId];
return `Rule '${ruleId}' was removed and replaced by: ${newRules.join(", ")}`;
}
return null;
}
const eslintEnvPattern = /\/\*\s*eslint-env\s(.+?)\*\//g;
/**
* Checks whether or not there is a comment which has "eslint-env *" in a given text.
* @param {string} text - A source code text to check.
* @returns {Object|null} A result of parseListConfig() with "eslint-env *" comment.
*/
function findEslintEnv(text) {
let match, retv;
eslintEnvPattern.lastIndex = 0;
while ((match = eslintEnvPattern.exec(text))) {
retv = Object.assign(retv || {}, parseListConfig(match[1]));
}
return retv;
}
/**
* Strips Unicode BOM from a given text.
*
* @param {string} text - A text to strip.
* @returns {string} The stripped text.
*/
function stripUnicodeBOM(text) {
/*
* Check Unicode BOM.
* In JavaScript, string data is stored as UTF-16, so BOM is 0xFEFF.
* http://www.ecma-international.org/ecma-262/6.0/#sec-unicode-format-control-characters
*/
if (text.charCodeAt(0) === 0xFEFF) {
return text.slice(1);
}
return text;
}
//------------------------------------------------------------------------------
// Public Interface
//------------------------------------------------------------------------------
/**
* Object that is responsible for verifying JavaScript text
* @name eslint
*/
module.exports = (function() {
const api = Object.create(new EventEmitter());
let messages = [],
currentConfig = null,
currentScopes = null,
scopeManager = null,
currentFilename = null,
traverser = null,
reportingConfig = [],
sourceCode = null;
/**
* Parses text into an AST. Moved out here because the try-catch prevents
* optimization of functions, so it's best to keep the try-catch as isolated
* as possible
* @param {string} text The text to parse.
* @param {Object} config The ESLint configuration object.
* @param {string} filePath The path to the file being parsed.
* @returns {ASTNode|CustomParseResult} The AST or parse result if successful,
* or null if not.
* @private
*/
function parse(text, config, filePath) {
let parser,
parserOptions = {
loc: true,
range: true,
raw: true,
tokens: true,
comment: true,
attachComment: true,
filePath
};
try {
parser = require(config.parser);
} catch (ex) {
messages.push({
ruleId: null,
fatal: true,
severity: 2,
source: null,
message: ex.message,
line: 0,
column: 0
});
return null;
}
// merge in any additional parser options
if (config.parserOptions) {
parserOptions = Object.assign({}, config.parserOptions, parserOptions);
}
/*
* Check for parsing errors first. If there's a parsing error, nothing
* else can happen. However, a parsing error does not throw an error
* from this method - it's just considered a fatal error message, a
* problem that ESLint identified just like any other.
*/
try {
if (typeof parser.parseForESLint === "function") {
return parser.parseForESLint(text, parserOptions);
} else {
return parser.parse(text, parserOptions);
}
} catch (ex) {
// If the message includes a leading line number, strip it:
const message = ex.message.replace(/^line \d+:/i, "").trim();
const source = (ex.lineNumber) ? SourceCode.splitLines(text)[ex.lineNumber - 1] : null;
messages.push({
ruleId: null,
fatal: true,
severity: 2,
source,
message: `Parsing error: ${message}`,
line: ex.lineNumber,
column: ex.column
});
return null;
}
}
/**
* Get the severity level of a rule (0 - none, 1 - warning, 2 - error)
* Returns 0 if the rule config is not valid (an Array or a number)
* @param {Array|number} ruleConfig rule configuration
* @returns {number} 0, 1, or 2, indicating rule severity
*/
function getRuleSeverity(ruleConfig) {
if (typeof ruleConfig === "number") {
return ruleConfig;
} else if (Array.isArray(ruleConfig)) {
return ruleConfig[0];
} else {
return 0;
}
}
/**
* Get the options for a rule (not including severity), if any
* @param {Array|number} ruleConfig rule configuration
* @returns {Array} of rule options, empty Array if none
*/
function getRuleOptions(ruleConfig) {
if (Array.isArray(ruleConfig)) {
return ruleConfig.slice(1);
} else {
return [];
}
}
// set unlimited listeners (see https://github.com/eslint/eslint/issues/524)
api.setMaxListeners(0);
/**
* Resets the internal state of the object.
* @returns {void}
*/
api.reset = function() {
this.removeAllListeners();
messages = [];
currentConfig = null;
currentScopes = null;
scopeManager = null;
traverser = null;
reportingConfig = [];
sourceCode = null;
};
/**
* Configuration object for the `verify` API. A JS representation of the eslintrc files.
* @typedef {Object} ESLintConfig
* @property {Object} rules The rule configuration to verify against.
* @property {string} [parser] Parser to use when generatig the AST.
* @property {Object} [parserOptions] Options for the parsed used.
* @property {Object} [settings] Global settings passed to each rule.
* @property {Object} [env] The environment to verify in.
* @property {Object} [globals] Available globalsto the code.
*/
/**
* Verifies the text against the rules specified by the second argument.
* @param {string|SourceCode} textOrSourceCode The text to parse or a SourceCode object.
* @param {ESLintConfig} config An ESLintConfig instance to configure everything.
* @param {(string|Object)} [filenameOrOptions] The optional filename of the file being checked.
* If this is not set, the filename will default to '' in the rule context. If
* an object, then it has "filename", "saveState", and "allowInlineConfig" properties.
* @param {boolean} [saveState] Indicates if the state from the last run should be saved.
* Mostly useful for testing purposes.
* @param {boolean} [filenameOrOptions.allowInlineConfig] Allow/disallow inline comments' ability to change config once it is set. Defaults to true if not supplied.
* Useful if you want to validate JS without comments overriding rules.
* @returns {Object[]} The results as an array of messages or null if no messages.
*/
api.verify = function(textOrSourceCode, config, filenameOrOptions, saveState) {
const text = (typeof textOrSourceCode === "string") ? textOrSourceCode : null;
let ast,
parseResult,
shebang,
allowInlineConfig;
// evaluate arguments
if (typeof filenameOrOptions === "object") {
currentFilename = filenameOrOptions.filename;
allowInlineConfig = filenameOrOptions.allowInlineConfig;
saveState = filenameOrOptions.saveState;
} else {
currentFilename = filenameOrOptions;
}
if (!saveState) {
this.reset();
}
// search and apply "eslint-env *".
const envInFile = findEslintEnv(text || textOrSourceCode.text);
if (envInFile) {
if (!config || !config.env) {
config = Object.assign({}, config || {}, { env: envInFile });
} else {
config = Object.assign({}, config);
config.env = Object.assign({}, config.env, envInFile);
}
}
// process initial config to make it safe to extend
config = prepareConfig(config || {});
// only do this for text
if (text !== null) {
// there's no input, just exit here
if (text.trim().length === 0) {
sourceCode = new SourceCode(text, blankScriptAST);
return messages;
}
parseResult = parse(
stripUnicodeBOM(text).replace(/^#!([^\r\n]+)/, (match, captured) => {
shebang = captured;
return `//${captured}`;
}),
config,
currentFilename
);
// if this result is from a parseForESLint() method, normalize
if (parseResult && parseResult.ast) {
ast = parseResult.ast;
} else {
ast = parseResult;
parseResult = null;
}
if (ast) {
sourceCode = new SourceCode(text, ast);
}
} else {
sourceCode = textOrSourceCode;
ast = sourceCode.ast;
}
// if espree failed to parse the file, there's no sense in setting up rules
if (ast) {
// parse global comments and modify config
if (allowInlineConfig !== false) {
config = modifyConfigsFromComments(currentFilename, ast, config, reportingConfig, messages);
}
// ensure that severities are normalized in the config
ConfigOps.normalize(config);
// enable appropriate rules
Object.keys(config.rules).filter(key => getRuleSeverity(config.rules[key]) > 0).forEach(key => {
let ruleCreator;
ruleCreator = rules.get(key);
if (!ruleCreator) {
const replacementMsg = getRuleReplacementMessage(key);
if (replacementMsg) {
ruleCreator = createStubRule(replacementMsg);
} else {
ruleCreator = createStubRule(`Definition for rule '${key}' was not found`);
}
rules.define(key, ruleCreator);
}
const severity = getRuleSeverity(config.rules[key]);
const options = getRuleOptions(config.rules[key]);
try {
const ruleContext = new RuleContext(
key, api, severity, options,
config.settings, config.parserOptions, config.parser,
ruleCreator.meta,
(parseResult && parseResult.services ? parseResult.services : {})
);
const rule = ruleCreator.create ? ruleCreator.create(ruleContext) :
ruleCreator(ruleContext);
// add all the node types as listeners
Object.keys(rule).forEach(nodeType => {
api.on(nodeType, timing.enabled
? timing.time(key, rule[nodeType])
: rule[nodeType]
);
});
} catch (ex) {
ex.message = `Error while loading rule '${key}': ${ex.message}`;
throw ex;
}
});
// save config so rules can access as necessary
currentConfig = config;
traverser = new Traverser();
const ecmaFeatures = currentConfig.parserOptions.ecmaFeatures || {};
const ecmaVersion = currentConfig.parserOptions.ecmaVersion || 5;
// gather scope data that may be needed by the rules
scopeManager = escope.analyze(ast, {
ignoreEval: true,
nodejsScope: ecmaFeatures.globalReturn,
impliedStrict: ecmaFeatures.impliedStrict,
ecmaVersion,
sourceType: currentConfig.parserOptions.sourceType || "script",
fallback: Traverser.getKeys
});
currentScopes = scopeManager.scopes;
// augment global scope with declared global variables
addDeclaredGlobals(ast, currentScopes[0], currentConfig);
// remove shebang comments
if (shebang && ast.comments.length && ast.comments[0].value === shebang) {
ast.comments.splice(0, 1);
if (ast.body.length && ast.body[0].leadingComments && ast.body[0].leadingComments[0].value === shebang) {
ast.body[0].leadingComments.splice(0, 1);
}
}
let eventGenerator = new NodeEventGenerator(api);
eventGenerator = new CodePathAnalyzer(eventGenerator);
eventGenerator = new CommentEventGenerator(eventGenerator, sourceCode);
/*
* Each node has a type property. Whenever a particular type of
* node is found, an event is fired. This allows any listeners to
* automatically be informed that this type of node has been found
* and react accordingly.
*/
traverser.traverse(ast, {
enter(node, parent) {
node.parent = parent;
eventGenerator.enterNode(node);
},
leave(node) {
eventGenerator.leaveNode(node);
}
});
}
// sort by line and column
messages.sort((a, b) => {
const lineDiff = a.line - b.line;
if (lineDiff === 0) {
return a.column - b.column;
} else {
return lineDiff;
}
});
return messages;
};
/**
* Reports a message from one of the rules.
* @param {string} ruleId The ID of the rule causing the message.
* @param {number} severity The severity level of the rule as configured.
* @param {ASTNode} node The AST node that the message relates to.
* @param {Object=} location An object containing the error line and column
* numbers. If location is not provided the node's start location will
* be used.
* @param {string} message The actual message.
* @param {Object} opts Optional template data which produces a formatted message
* with symbols being replaced by this object's values.
* @param {Object} fix A fix command description.
* @param {Object} meta Metadata of the rule
* @returns {void}
*/
api.report = function(ruleId, severity, node, location, message, opts, fix, meta) {
if (node) {
assert.strictEqual(typeof node, "object", "Node must be an object");
}
if (typeof location === "string") {
assert.ok(node, "Node must be provided when reporting error if location is not provided");
meta = fix;
fix = opts;
opts = message;
message = location;
location = node.loc.start;
}
// Store end location.
const endLocation = location.end;
location = location.start || location;
if (isDisabledByReportingConfig(reportingConfig, ruleId, location)) {
return;
}
if (opts) {
message = message.replace(/\{\{\s*([^{}]+?)\s*\}\}/g, (fullMatch, term) => {
if (term in opts) {
return opts[term];
}
// Preserve old behavior: If parameter name not provided, don't replace it.
return fullMatch;
});
}
const problem = {
ruleId,
severity,
message,
line: location.line,
column: location.column + 1, // switch to 1-base instead of 0-base
nodeType: node && node.type,
source: sourceCode.lines[location.line - 1] || ""
};
// Define endLine and endColumn if exists.
if (endLocation) {
problem.endLine = endLocation.line;
problem.endColumn = endLocation.column + 1; // switch to 1-base instead of 0-base
}
// ensure there's range and text properties, otherwise it's not a valid fix
if (fix && Array.isArray(fix.range) && (typeof fix.text === "string")) {
// If rule uses fix, has metadata, but has no metadata.fixable, we should throw
if (meta && !meta.fixable) {
throw new Error("Fixable rules should export a `meta.fixable` property.");
}
problem.fix = fix;
}
messages.push(problem);
};
/**
* Gets the SourceCode object representing the parsed source.
* @returns {SourceCode} The SourceCode object.
*/
api.getSourceCode = function() {
return sourceCode;
};
// methods that exist on SourceCode object
const externalMethods = {
getSource: "getText",
getSourceLines: "getLines",
getAllComments: "getAllComments",
getNodeByRangeIndex: "getNodeByRangeIndex",
getComments: "getComments",
getJSDocComment: "getJSDocComment",
getFirstToken: "getFirstToken",
getFirstTokens: "getFirstTokens",
getLastToken: "getLastToken",
getLastTokens: "getLastTokens",
getTokenAfter: "getTokenAfter",
getTokenBefore: "getTokenBefore",
getTokenByRangeStart: "getTokenByRangeStart",
getTokens: "getTokens",
getTokensAfter: "getTokensAfter",
getTokensBefore: "getTokensBefore",
getTokensBetween: "getTokensBetween"
};
// copy over methods
Object.keys(externalMethods).forEach(methodName => {
const exMethodName = externalMethods[methodName];
// All functions expected to have less arguments than 5.
api[methodName] = function(a, b, c, d, e) {
if (sourceCode) {
return sourceCode[exMethodName](a, b, c, d, e);
}
return null;
};
});
/**
* Gets nodes that are ancestors of current node.
* @returns {ASTNode[]} Array of objects representing ancestors.
*/
api.getAncestors = function() {
return traverser.parents();
};
/**
* Gets the scope for the current node.
* @returns {Object} An object representing the current node's scope.
*/
api.getScope = function() {
const parents = traverser.parents();
// Don't do this for Program nodes - they have no parents
if (parents.length) {
// if current node introduces a scope, add it to the list
const current = traverser.current();
if (currentConfig.parserOptions.ecmaVersion >= 6) {
if (["BlockStatement", "SwitchStatement", "CatchClause", "FunctionDeclaration", "FunctionExpression", "ArrowFunctionExpression"].indexOf(current.type) >= 0) {
parents.push(current);
}
} else {
if (["FunctionDeclaration", "FunctionExpression", "ArrowFunctionExpression"].indexOf(current.type) >= 0) {
parents.push(current);
}
}
// Ascend the current node's parents
for (let i = parents.length - 1; i >= 0; --i) {
// Get the innermost scope
const scope = scopeManager.acquire(parents[i], true);
if (scope) {
if (scope.type === "function-expression-name") {
return scope.childScopes[0];
} else {
return scope;
}
}
}
}
return currentScopes[0];
};
/**
* Record that a particular variable has been used in code
* @param {string} name The name of the variable to mark as used
* @returns {boolean} True if the variable was found and marked as used,
* false if not.
*/
api.markVariableAsUsed = function(name) {
const hasGlobalReturn = currentConfig.parserOptions.ecmaFeatures && currentConfig.parserOptions.ecmaFeatures.globalReturn,
specialScope = hasGlobalReturn || currentConfig.parserOptions.sourceType === "module";
let scope = this.getScope(),
i,
len;
// Special Node.js scope means we need to start one level deeper
if (scope.type === "global" && specialScope) {
scope = scope.childScopes[0];
}
do {
const variables = scope.variables;
for (i = 0, len = variables.length; i < len; i++) {
if (variables[i].name === name) {
variables[i].eslintUsed = true;
return true;
}
}
} while ((scope = scope.upper));
return false;
};
/**
* Gets the filename for the currently parsed source.
* @returns {string} The filename associated with the source being parsed.
* Defaults to "" if no filename info is present.
*/
api.getFilename = function() {
if (typeof currentFilename === "string") {
return currentFilename;
} else {
return "";
}
};
/**
* Defines a new linting rule.
* @param {string} ruleId A unique rule identifier
* @param {Function} ruleModule Function from context to object mapping AST node types to event handlers
* @returns {void}
*/
const defineRule = api.defineRule = function(ruleId, ruleModule) {
rules.define(ruleId, ruleModule);
};
/**
* Defines many new linting rules.
* @param {Object} rulesToDefine map from unique rule identifier to rule
* @returns {void}
*/
api.defineRules = function(rulesToDefine) {
Object.getOwnPropertyNames(rulesToDefine).forEach(ruleId => {
defineRule(ruleId, rulesToDefine[ruleId]);
});
};
/**
* Gets the default eslint configuration.
* @returns {Object} Object mapping rule IDs to their default configurations
*/
api.defaults = function() {
return require("../conf/eslint.json");
};
/**
* Gets an object with all loaded rules.
* @returns {Map} All loaded rules
*/
api.getRules = function() {
return rules.getAllLoadedRules();
};
api.version = pkg.version;
/**
* Gets variables that are declared by a specified node.
*
* The variables are its `defs[].node` or `defs[].parent` is same as the specified node.
* Specifically, below:
*
* - `VariableDeclaration` - variables of its all declarators.
* - `VariableDeclarator` - variables.
* - `FunctionDeclaration`/`FunctionExpression` - its function name and parameters.
* - `ArrowFunctionExpression` - its parameters.
* - `ClassDeclaration`/`ClassExpression` - its class name.
* - `CatchClause` - variables of its exception.
* - `ImportDeclaration` - variables of its all specifiers.
* - `ImportSpecifier`/`ImportDefaultSpecifier`/`ImportNamespaceSpecifier` - a variable.
* - others - always an empty array.
*
* @param {ASTNode} node A node to get.
* @returns {escope.Variable[]} Variables that are declared by the node.
*/
api.getDeclaredVariables = function(node) {
return (scopeManager && scopeManager.getDeclaredVariables(node)) || [];
};
return api;
}());