Files
tubestation/tools/lint/eslint/eslint-plugin-mozilla/lib/helpers.js
2018-05-25 22:27:00 -07:00

731 lines
22 KiB
JavaScript

/**
* @fileoverview A collection of helper functions.
* This Source Code Form is subject to the terms of the Mozilla Public
* License, v. 2.0. If a copy of the MPL was not distributed with this
* file, You can obtain one at http://mozilla.org/MPL/2.0/.
*/
"use strict";
const espree = require("espree");
const estraverse = require("estraverse");
const path = require("path");
const fs = require("fs");
const ini = require("ini-parser");
var gModules = null;
var gRootDir = null;
var directoryManifests = new Map();
const callExpressionDefinitions = [
/^loader\.lazyGetter\(this, "(\w+)"/,
/^loader\.lazyImporter\(this, "(\w+)"/,
/^loader\.lazyServiceGetter\(this, "(\w+)"/,
/^loader\.lazyRequireGetter\(this, "(\w+)"/,
/^XPCOMUtils\.defineLazyGetter\(this, "(\w+)"/,
/^XPCOMUtils\.defineLazyModuleGetter\(this, "(\w+)"/,
/^ChromeUtils\.defineModuleGetter\(this, "(\w+)"/,
/^XPCOMUtils\.defineLazyPreferenceGetter\(this, "(\w+)"/,
/^XPCOMUtils\.defineLazyProxy\(this, "(\w+)"/,
/^XPCOMUtils\.defineLazyScriptGetter\(this, "(\w+)"/,
/^XPCOMUtils\.defineLazyServiceGetter\(this, "(\w+)"/,
/^XPCOMUtils\.defineConstant\(this, "(\w+)"/,
/^DevToolsUtils\.defineLazyModuleGetter\(this, "(\w+)"/,
/^DevToolsUtils\.defineLazyGetter\(this, "(\w+)"/,
/^Object\.defineProperty\(this, "(\w+)"/,
/^Reflect\.defineProperty\(this, "(\w+)"/,
/^this\.__defineGetter__\("(\w+)"/
];
const callExpressionMultiDefinitions = [
"XPCOMUtils.defineLazyGlobalGetters(this,",
"XPCOMUtils.defineLazyModuleGetters(this,",
"XPCOMUtils.defineLazyServiceGetters(this,"
];
const imports = [
/^(?:Cu|Components\.utils|ChromeUtils)\.import\(".*\/((.*?)\.jsm?)"(?:, this)?\)/
];
const workerImportFilenameMatch = /(.*\/)*(.*?\.jsm?)/;
module.exports = {
get modulesGlobalData() {
if (!gModules) {
if (this.isMozillaCentralBased()) {
gModules = require(path.join(this.rootDir, "tools", "lint", "eslint", "modules.json"));
} else {
gModules = require("./modules.json");
}
}
return gModules;
},
/**
* Gets the abstract syntax tree (AST) of the JavaScript source code contained
* in sourceText.
*
* @param {String} sourceText
* Text containing valid JavaScript.
*
* @return {Object}
* The resulting AST.
*/
getAST(sourceText) {
// Use a permissive config file to allow parsing of anything that Espree
// can parse.
var config = this.getPermissiveConfig();
return espree.parse(sourceText, config);
},
/**
* A simplistic conversion of some AST nodes to a standard string form.
*
* @param {Object} node
* The AST node to convert.
*
* @return {String}
* The JS source for the node.
*/
getASTSource(node, context) {
switch (node.type) {
case "MemberExpression":
if (node.computed) {
let filename = context && context.getFilename();
throw new Error(`getASTSource unsupported computed MemberExpression in ${filename}`);
}
return this.getASTSource(node.object) + "." +
this.getASTSource(node.property);
case "ThisExpression":
return "this";
case "Identifier":
return node.name;
case "Literal":
return JSON.stringify(node.value);
case "CallExpression":
var args = node.arguments.map(a => this.getASTSource(a)).join(", ");
return this.getASTSource(node.callee) + "(" + args + ")";
case "ObjectExpression":
return "{}";
case "ExpressionStatement":
return this.getASTSource(node.expression) + ";";
case "FunctionExpression":
return "function() {}";
case "ArrayExpression":
return "[" + node.elements.map(this.getASTSource, this).join(",") + "]";
case "ArrowFunctionExpression":
return "() => {}";
case "AssignmentExpression":
return this.getASTSource(node.left) + " = " +
this.getASTSource(node.right);
case "BinaryExpression":
return this.getASTSource(node.left) + " " + node.operator + " " + this.getASTSource(node.right);
default:
throw new Error("getASTSource unsupported node type: " + node.type);
}
},
/**
* This walks an AST in a manner similar to ESLint passing node events to the
* listener. The listener is expected to be a simple function
* which accepts node type, node and parents arguments.
*
* @param {Object} ast
* The AST to walk.
* @param {Function} listener
* A callback function to call for the nodes. Passed three arguments,
* event type, node and an array of parent nodes for the current node.
*/
walkAST(ast, listener) {
let parents = [];
estraverse.traverse(ast, {
enter(node, parent) {
listener(node.type, node, parents);
parents.push(node);
},
leave(node, parent) {
if (parents.length == 0) {
throw new Error("Left more nodes than entered.");
}
parents.pop();
}
});
if (parents.length) {
throw new Error("Entered more nodes than left.");
}
},
/**
* Attempts to convert an ExpressionStatement to likely global variable
* definitions.
*
* @param {Object} node
* The AST node to convert.
* @param {boolean} isGlobal
* True if the current node is in the global scope.
*
* @return {Array}
* An array of objects that contain details about the globals:
* - {String} name
* The name of the global.
* - {Boolean} writable
* If the global is writeable or not.
*/
convertWorkerExpressionToGlobals(node, isGlobal, dirname) {
var getGlobalsForFile = require("./globals").getGlobalsForFile;
let globalModules = this.modulesGlobalData;
let results = [];
let expr = node.expression;
if (node.expression.type === "CallExpression" &&
expr.callee &&
expr.callee.type === "Identifier" &&
expr.callee.name === "importScripts") {
for (var arg of expr.arguments) {
var match = arg.value && arg.value.match(workerImportFilenameMatch);
if (match) {
if (!match[1]) {
let filePath = path.resolve(dirname, match[2]);
if (fs.existsSync(filePath)) {
let additionalGlobals = getGlobalsForFile(filePath);
results = results.concat(additionalGlobals);
}
} else if (match[2] in globalModules) {
results = results.concat(globalModules[match[2]].map(name => {
return { name, writable: true };
}));
}
}
}
}
return results;
},
/**
* Attempts to convert an AssignmentExpression into a global variable
* definition if it applies to `this` in the global scope.
*
* @param {Object} node
* The AST node to convert.
* @param {boolean} isGlobal
* True if the current node is in the global scope.
*
* @return {Array}
* An array of objects that contain details about the globals:
* - {String} name
* The name of the global.
* - {Boolean} writable
* If the global is writeable or not.
*/
convertThisAssignmentExpressionToGlobals(node, isGlobal) {
if (isGlobal &&
node.expression.left &&
node.expression.left.object &&
node.expression.left.object.type === "ThisExpression" &&
node.expression.left.property &&
node.expression.left.property.type === "Identifier") {
return [{ name: node.expression.left.property.name, writable: true }];
}
return [];
},
/**
* Attempts to convert an CallExpressions that look like module imports
* into global variable definitions, using modules.json data if appropriate.
*
* @param {Object} node
* The AST node to convert.
* @param {boolean} isGlobal
* True if the current node is in the global scope.
*
* @return {Array}
* An array of objects that contain details about the globals:
* - {String} name
* The name of the global.
* - {Boolean} writable
* If the global is writeable or not.
*/
convertCallExpressionToGlobals(node, isGlobal) {
let express = node.expression;
if (express.type === "CallExpression" &&
express.callee.type === "MemberExpression" &&
express.callee.object &&
express.callee.object.type === "Identifier" &&
express.arguments.length === 1 &&
express.arguments[0].type === "ArrayExpression" &&
express.callee.property.type === "Identifier" &&
express.callee.property.name === "importGlobalProperties") {
return express.arguments[0].elements.map(literal => {
return {
name: literal.value,
writable: false
};
});
}
let source;
try {
source = this.getASTSource(node);
} catch (e) {
return [];
}
for (let reg of imports) {
let match = source.match(reg);
if (match) {
// The two argument form is only acceptable in the global scope
if (node.expression.arguments.length > 1 && !isGlobal) {
return [];
}
let globalModules = this.modulesGlobalData;
if (match[1] in globalModules) {
return globalModules[match[1]].map(name => ({ name, writable: true }));
}
return [{ name: match[2], writable: true }];
}
}
// The definition matches below must be in the global scope for us to define
// a global, so bail out early if we're not a global.
if (!isGlobal) {
return [];
}
for (let reg of callExpressionDefinitions) {
let match = source.match(reg);
if (match) {
return [{ name: match[1], writable: true, explicit: true }];
}
}
if (callExpressionMultiDefinitions.some(expr => source.startsWith(expr)) &&
node.expression.arguments[1]) {
let arg = node.expression.arguments[1];
if (arg.type === "ObjectExpression") {
return arg.properties
.map(p => ({ name: p.type === "Property" && p.key.name, writable: true, explicit: true }))
.filter(g => g.name);
}
if (arg.type === "ArrayExpression") {
return arg.elements
.map(p => ({ name: p.type === "Literal" && p.value, writable: true, explicit: true }))
.filter(g => typeof g.name == "string");
}
}
if (node.expression.callee.type == "MemberExpression" &&
node.expression.callee.property.type == "Identifier" &&
node.expression.callee.property.name == "defineLazyScriptGetter") {
// The case where we have a single symbol as a string has already been
// handled by the regexp, so we have an array of symbols here.
return node.expression.arguments[1].elements.map(n => ({ name: n.value, writable: true, explicit: true }));
}
return [];
},
/**
* Add a variable to the current scope.
* HACK: This relies on eslint internals so it could break at any time.
*
* @param {String} name
* The variable name to add to the scope.
* @param {ASTScope} scope
* The scope to add to.
* @param {boolean} writable
* Whether the global can be overwritten.
* @param {Object} [node]
* The AST node that defined the globals.
*/
addVarToScope(name, scope, writable, node) {
scope.__defineGeneric(name, scope.set, scope.variables, null, null);
let variable = scope.set.get(name);
variable.eslintExplicitGlobal = false;
variable.writeable = writable;
if (node) {
variable.defs.push({node, name: {name}});
variable.identifiers.push(node);
}
// Walk to the global scope which holds all undeclared variables.
while (scope.type != "global") {
scope = scope.upper;
}
// "through" contains all references with no found definition.
scope.through = scope.through.filter(function(reference) {
if (reference.identifier.name != name) {
return true;
}
// Links the variable and the reference.
// And this reference is removed from `Scope#through`.
reference.resolved = variable;
variable.references.push(reference);
return false;
});
},
/**
* Adds a set of globals to a scope.
*
* @param {Array} globalVars
* An array of global variable names.
* @param {ASTScope} scope
* The scope.
* @param {Object} [node]
* The AST node that defined the globals.
*/
addGlobals(globalVars, scope, node) {
globalVars.forEach(v => this.addVarToScope(v.name, scope, v.writable, v.explicit && node));
},
/**
* To allow espree to parse almost any JavaScript we need as many features as
* possible turned on. This method returns that config.
*
* @return {Object}
* Espree compatible permissive config.
*/
getPermissiveConfig() {
return {
range: true,
loc: true,
comment: true,
attachComment: true,
ecmaVersion: 9,
sourceType: "script"
};
},
/**
* Check whether a node is a function.
*
* @param {Object} node
* The AST node to check
*
* @return {Boolean}
* True or false
*/
getIsFunctionNode(node) {
switch (node.type) {
case "ArrowFunctionExpression":
case "FunctionDeclaration":
case "FunctionExpression":
return true;
}
return false;
},
/**
* Check whether the context is the global scope.
*
* @param {Array} ancestors
* The parents of the current node.
*
* @return {Boolean}
* True or false
*/
getIsGlobalScope(ancestors) {
for (let parent of ancestors) {
if (this.getIsFunctionNode(parent)) {
return false;
}
}
return true;
},
/**
* Check whether we might be in a test head file.
*
* @param {RuleContext} scope
* You should pass this from within a rule
* e.g. helpers.getIsHeadFile(context)
*
* @return {Boolean}
* True or false
*/
getIsHeadFile(scope) {
var pathAndFilename = this.cleanUpPath(scope.getFilename());
return /.*[\\/]head(_.+)?\.js$/.test(pathAndFilename);
},
/**
* Gets the head files for a potential test file
*
* @param {RuleContext} scope
* You should pass this from within a rule
* e.g. helpers.getIsHeadFile(context)
*
* @return {String[]}
* Paths to head files to load for the test
*/
getTestHeadFiles(scope) {
if (!this.getIsTest(scope)) {
return [];
}
let filepath = this.cleanUpPath(scope.getFilename());
let dir = path.dirname(filepath);
let names =
fs.readdirSync(dir)
.filter(name => (name.startsWith("head") ||
name.startsWith("xpcshell-head")) && name.endsWith(".js"))
.map(name => path.join(dir, name));
return names;
},
/**
* Gets all the test manifest data for a directory
*
* @param {String} dir
* The directory
*
* @return {Array}
* An array of objects with file and manifest properties
*/
getManifestsForDirectory(dir) {
if (directoryManifests.has(dir)) {
return directoryManifests.get(dir);
}
let manifests = [];
let names = [];
try {
names = fs.readdirSync(dir);
} catch (err) {
// Ignore directory not found, it might be faked by a test
if (err.code !== "ENOENT") {
throw err;
}
}
for (let name of names) {
if (!name.endsWith(".ini")) {
continue;
}
try {
let manifest = ini.parse(fs.readFileSync(path.join(dir, name), "utf8"));
manifests.push({
file: path.join(dir, name),
manifest
});
} catch (e) {
}
}
directoryManifests.set(dir, manifests);
return manifests;
},
/**
* Gets the manifest file a test is listed in
*
* @param {RuleContext} scope
* You should pass this from within a rule
* e.g. helpers.getIsHeadFile(context)
*
* @return {String}
* The path to the test manifest file
*/
getTestManifest(scope) {
let filepath = this.cleanUpPath(scope.getFilename());
let dir = path.dirname(filepath);
let filename = path.basename(filepath);
for (let manifest of this.getManifestsForDirectory(dir)) {
if (filename in manifest.manifest) {
return manifest.file;
}
}
return null;
},
/**
* Check whether we are in a test of some kind.
*
* @param {RuleContext} scope
* You should pass this from within a rule
* e.g. helpers.getIsTest(context)
*
* @return {Boolean}
* True or false
*/
getIsTest(scope) {
// Regardless of the manifest name being in a manifest means we're a test.
let manifest = this.getTestManifest(scope);
if (manifest) {
return true;
}
return !!this.getTestType(scope);
},
/**
* Gets the type of test or null if this isn't a test.
*
* @param {RuleContext} scope
* You should pass this from within a rule
* e.g. helpers.getIsHeadFile(context)
*
* @return {String or null}
* Test type: xpcshell, browser, chrome, mochitest
*/
getTestType(scope) {
let testTypes = ["browser", "xpcshell", "chrome", "mochitest", "a11y"];
let manifest = this.getTestManifest(scope);
if (manifest) {
let name = path.basename(manifest);
for (let testType of testTypes) {
if (name.startsWith(testType)) {
return testType;
}
}
}
let filepath = this.cleanUpPath(scope.getFilename());
let filename = path.basename(filepath);
if (filename.startsWith("browser_")) {
return "browser";
}
if (filename.startsWith("test_")) {
let parent = path.basename(path.dirname(filepath));
for (let testType of testTypes) {
if (parent.startsWith(testType)) {
return testType;
}
}
// It likely is a test, we're just not sure what kind.
return "unknown";
}
// Likely not a test
return null;
},
getIsWorker(filePath) {
let filename = path.basename(this.cleanUpPath(filePath)).toLowerCase();
return filename.includes("worker");
},
/**
* Gets the root directory of the repository by walking up directories from
* this file until a .eslintignore file is found. If this fails, the same
* procedure will be attempted from the current working dir.
* @return {String} The absolute path of the repository directory
*/
get rootDir() {
if (!gRootDir) {
function searchUpForIgnore(dirName, filename) {
let parsed = path.parse(dirName);
while (parsed.root !== dirName) {
if (fs.existsSync(path.join(dirName, filename))) {
return dirName;
}
// Move up a level
dirName = parsed.dir;
parsed = path.parse(dirName);
}
return null;
}
let possibleRoot = searchUpForIgnore(path.dirname(module.filename), ".eslintignore");
if (!possibleRoot) {
possibleRoot = searchUpForIgnore(path.resolve(), ".eslintignore");
}
if (!possibleRoot) {
possibleRoot = searchUpForIgnore(path.resolve(), "package.json");
}
if (!possibleRoot) {
// We've couldn't find a root from the module or CWD, so lets just go
// for the CWD. We really don't want to throw if possible, as that
// tends to give confusing results when used with ESLint.
possibleRoot = process.cwd();
}
gRootDir = possibleRoot;
}
return gRootDir;
},
/**
* ESLint may be executed from various places: from mach, at the root of the
* repository, or from a directory in the repository when, for instance,
* executed by a text editor's plugin.
* The value returned by context.getFileName() varies because of this.
* This helper function makes sure to return an absolute file path for the
* current context, by looking at process.cwd().
* @param {Context} context
* @return {String} The absolute path
*/
getAbsoluteFilePath(context) {
var fileName = this.cleanUpPath(context.getFilename());
var cwd = process.cwd();
if (path.isAbsolute(fileName)) {
// Case 2: executed from the repo's root with mach:
// fileName: /path/to/mozilla/repo/a/b/c/d.js
// cwd: /path/to/mozilla/repo
return fileName;
} else if (path.basename(fileName) == fileName) {
// Case 1b: executed from a nested directory, fileName is the base name
// without any path info (happens in Atom with linter-eslint)
return path.join(cwd, fileName);
}
// Case 1: executed form in a nested directory, e.g. from a text editor:
// fileName: a/b/c/d.js
// cwd: /path/to/mozilla/repo/a/b/c
var dirName = path.dirname(fileName);
return cwd.slice(0, cwd.length - dirName.length) + fileName;
},
/**
* When ESLint is run from SublimeText, paths retrieved from
* context.getFileName contain leading and trailing double-quote characters.
* These characters need to be removed.
*/
cleanUpPath(pathName) {
return pathName.replace(/^"/, "").replace(/"$/, "");
},
get globalScriptsPath() {
return path.join(this.rootDir, "browser",
"base", "content", "global-scripts.inc");
},
isMozillaCentralBased() {
return fs.existsSync(this.globalScriptsPath);
},
getSavedEnvironmentItems(environment) {
return require("./environments/saved-globals.json").environments[environment];
},
getSavedRuleData(rule) {
return require("./rules/saved-rules-data.json").rulesData[rule];
}
};