+++ /dev/null
-/*
- Copyright (C) 2015 Yusuke Suzuki <utatane.tea@gmail.com>
-
- Redistribution and use in source and binary forms, with or without
- modification, are permitted provided that the following conditions are met:
-
- * Redistributions of source code must retain the above copyright
- notice, this list of conditions and the following disclaimer.
- * Redistributions in binary form must reproduce the above copyright
- notice, this list of conditions and the following disclaimer in the
- documentation and/or other materials provided with the distribution.
-
- THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS"
- AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
- IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
- ARE DISCLAIMED. IN NO EVENT SHALL <COPYRIGHT HOLDER> BE LIABLE FOR ANY
- DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES
- (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES;
- LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND
- ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
- (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
- THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
-*/
-"use strict";
-
-/* eslint-disable no-underscore-dangle */
-/* eslint-disable no-undefined */
-
-const Syntax = require("estraverse").Syntax;
-
-const Reference = require("./reference");
-const Variable = require("./variable");
-const Definition = require("./definition").Definition;
-const assert = require("assert");
-
-/**
- * Test if scope is struct
- * @param {Scope} scope - scope
- * @param {Block} block - block
- * @param {boolean} isMethodDefinition - is method definition
- * @param {boolean} useDirective - use directive
- * @returns {boolean} is strict scope
- */
-function isStrictScope(scope, block, isMethodDefinition, useDirective) {
- let body;
-
- // When upper scope is exists and strict, inner scope is also strict.
- if (scope.upper && scope.upper.isStrict) {
- return true;
- }
-
- if (isMethodDefinition) {
- return true;
- }
-
- if (scope.type === "class" || scope.type === "module") {
- return true;
- }
-
- if (scope.type === "block" || scope.type === "switch") {
- return false;
- }
-
- if (scope.type === "function") {
- if (block.type === Syntax.ArrowFunctionExpression && block.body.type !== Syntax.BlockStatement) {
- return false;
- }
-
- if (block.type === Syntax.Program) {
- body = block;
- } else {
- body = block.body;
- }
-
- if (!body) {
- return false;
- }
- } else if (scope.type === "global") {
- body = block;
- } else {
- return false;
- }
-
- // Search 'use strict' directive.
- if (useDirective) {
- for (let i = 0, iz = body.body.length; i < iz; ++i) {
- const stmt = body.body[i];
-
- if (stmt.type !== Syntax.DirectiveStatement) {
- break;
- }
- if (stmt.raw === "\"use strict\"" || stmt.raw === "'use strict'") {
- return true;
- }
- }
- } else {
- for (let i = 0, iz = body.body.length; i < iz; ++i) {
- const stmt = body.body[i];
-
- if (stmt.type !== Syntax.ExpressionStatement) {
- break;
- }
- const expr = stmt.expression;
-
- if (expr.type !== Syntax.Literal || typeof expr.value !== "string") {
- break;
- }
- if (expr.raw !== null && expr.raw !== undefined) {
- if (expr.raw === "\"use strict\"" || expr.raw === "'use strict'") {
- return true;
- }
- } else {
- if (expr.value === "use strict") {
- return true;
- }
- }
- }
- }
- return false;
-}
-
-/**
- * Register scope
- * @param {ScopeManager} scopeManager - scope manager
- * @param {Scope} scope - scope
- * @returns {void}
- */
-function registerScope(scopeManager, scope) {
- scopeManager.scopes.push(scope);
-
- const scopes = scopeManager.__nodeToScope.get(scope.block);
-
- if (scopes) {
- scopes.push(scope);
- } else {
- scopeManager.__nodeToScope.set(scope.block, [scope]);
- }
-}
-
-/**
- * Should be statically
- * @param {Object} def - def
- * @returns {boolean} should be statically
- */
-function shouldBeStatically(def) {
- return (
- (def.type === Variable.ClassName) ||
- (def.type === Variable.Variable && def.parent.kind !== "var")
- );
-}
-
-/**
- * @class Scope
- */
-class Scope {
- constructor(scopeManager, type, upperScope, block, isMethodDefinition) {
-
- /**
- * One of 'module', 'block', 'switch', 'function', 'catch', 'with', 'function', 'class', 'global'.
- * @member {String} Scope#type
- */
- this.type = type;
-
- /**
- * The scoped {@link Variable}s of this scope, as <code>{ Variable.name
- * : Variable }</code>.
- * @member {Map} Scope#set
- */
- this.set = new Map();
-
- /**
- * The tainted variables of this scope, as <code>{ Variable.name :
- * boolean }</code>.
- * @member {Map} Scope#taints */
- this.taints = new Map();
-
- /**
- * Generally, through the lexical scoping of JS you can always know
- * which variable an identifier in the source code refers to. There are
- * a few exceptions to this rule. With 'global' and 'with' scopes you
- * can only decide at runtime which variable a reference refers to.
- * Moreover, if 'eval()' is used in a scope, it might introduce new
- * bindings in this or its parent scopes.
- * All those scopes are considered 'dynamic'.
- * @member {boolean} Scope#dynamic
- */
- this.dynamic = this.type === "global" || this.type === "with";
-
- /**
- * A reference to the scope-defining syntax node.
- * @member {espree.Node} Scope#block
- */
- this.block = block;
-
- /**
- * The {@link Reference|references} that are not resolved with this scope.
- * @member {Reference[]} Scope#through
- */
- this.through = [];
-
- /**
- * The scoped {@link Variable}s of this scope. In the case of a
- * 'function' scope this includes the automatic argument <em>arguments</em> as
- * its first element, as well as all further formal arguments.
- * @member {Variable[]} Scope#variables
- */
- this.variables = [];
-
- /**
- * Any variable {@link Reference|reference} found in this scope. This
- * includes occurrences of local variables as well as variables from
- * parent scopes (including the global scope). For local variables
- * this also includes defining occurrences (like in a 'var' statement).
- * In a 'function' scope this does not include the occurrences of the
- * formal parameter in the parameter list.
- * @member {Reference[]} Scope#references
- */
- this.references = [];
-
- /**
- * For 'global' and 'function' scopes, this is a self-reference. For
- * other scope types this is the <em>variableScope</em> value of the
- * parent scope.
- * @member {Scope} Scope#variableScope
- */
- this.variableScope =
- (this.type === "global" || this.type === "function" || this.type === "module") ? this : upperScope.variableScope;
-
- /**
- * Whether this scope is created by a FunctionExpression.
- * @member {boolean} Scope#functionExpressionScope
- */
- this.functionExpressionScope = false;
-
- /**
- * Whether this is a scope that contains an 'eval()' invocation.
- * @member {boolean} Scope#directCallToEvalScope
- */
- this.directCallToEvalScope = false;
-
- /**
- * @member {boolean} Scope#thisFound
- */
- this.thisFound = false;
-
- this.__left = [];
-
- /**
- * Reference to the parent {@link Scope|scope}.
- * @member {Scope} Scope#upper
- */
- this.upper = upperScope;
-
- /**
- * Whether 'use strict' is in effect in this scope.
- * @member {boolean} Scope#isStrict
- */
- this.isStrict = isStrictScope(this, block, isMethodDefinition, scopeManager.__useDirective());
-
- /**
- * List of nested {@link Scope}s.
- * @member {Scope[]} Scope#childScopes
- */
- this.childScopes = [];
- if (this.upper) {
- this.upper.childScopes.push(this);
- }
-
- this.__declaredVariables = scopeManager.__declaredVariables;
-
- registerScope(scopeManager, this);
- }
-
- __shouldStaticallyClose(scopeManager) {
- return (!this.dynamic || scopeManager.__isOptimistic());
- }
-
- __shouldStaticallyCloseForGlobal(ref) {
-
- // On global scope, let/const/class declarations should be resolved statically.
- const name = ref.identifier.name;
-
- if (!this.set.has(name)) {
- return false;
- }
-
- const variable = this.set.get(name);
- const defs = variable.defs;
-
- return defs.length > 0 && defs.every(shouldBeStatically);
- }
-
- __staticCloseRef(ref) {
- if (!this.__resolve(ref)) {
- this.__delegateToUpperScope(ref);
- }
- }
-
- __dynamicCloseRef(ref) {
-
- // notify all names are through to global
- let current = this;
-
- do {
- current.through.push(ref);
- current = current.upper;
- } while (current);
- }
-
- __globalCloseRef(ref) {
-
- // let/const/class declarations should be resolved statically.
- // others should be resolved dynamically.
- if (this.__shouldStaticallyCloseForGlobal(ref)) {
- this.__staticCloseRef(ref);
- } else {
- this.__dynamicCloseRef(ref);
- }
- }
-
- __close(scopeManager) {
- let closeRef;
-
- if (this.__shouldStaticallyClose(scopeManager)) {
- closeRef = this.__staticCloseRef;
- } else if (this.type !== "global") {
- closeRef = this.__dynamicCloseRef;
- } else {
- closeRef = this.__globalCloseRef;
- }
-
- // Try Resolving all references in this scope.
- for (let i = 0, iz = this.__left.length; i < iz; ++i) {
- const ref = this.__left[i];
-
- closeRef.call(this, ref);
- }
- this.__left = null;
-
- return this.upper;
- }
-
- // To override by function scopes.
- // References in default parameters isn't resolved to variables which are in their function body.
- __isValidResolution(ref, variable) { // eslint-disable-line class-methods-use-this, no-unused-vars
- return true;
- }
-
- __resolve(ref) {
- const name = ref.identifier.name;
-
- if (!this.set.has(name)) {
- return false;
- }
- const variable = this.set.get(name);
-
- if (!this.__isValidResolution(ref, variable)) {
- return false;
- }
- variable.references.push(ref);
- variable.stack = variable.stack && ref.from.variableScope === this.variableScope;
- if (ref.tainted) {
- variable.tainted = true;
- this.taints.set(variable.name, true);
- }
- ref.resolved = variable;
-
- return true;
- }
-
- __delegateToUpperScope(ref) {
- if (this.upper) {
- this.upper.__left.push(ref);
- }
- this.through.push(ref);
- }
-
- __addDeclaredVariablesOfNode(variable, node) {
- if (node === null || node === undefined) {
- return;
- }
-
- let variables = this.__declaredVariables.get(node);
-
- if (variables === null || variables === undefined) {
- variables = [];
- this.__declaredVariables.set(node, variables);
- }
- if (variables.indexOf(variable) === -1) {
- variables.push(variable);
- }
- }
-
- __defineGeneric(name, set, variables, node, def) {
- let variable;
-
- variable = set.get(name);
- if (!variable) {
- variable = new Variable(name, this);
- set.set(name, variable);
- variables.push(variable);
- }
-
- if (def) {
- variable.defs.push(def);
- this.__addDeclaredVariablesOfNode(variable, def.node);
- this.__addDeclaredVariablesOfNode(variable, def.parent);
- }
- if (node) {
- variable.identifiers.push(node);
- }
- }
-
- __define(node, def) {
- if (node && node.type === Syntax.Identifier) {
- this.__defineGeneric(
- node.name,
- this.set,
- this.variables,
- node,
- def
- );
- }
- }
-
- __referencing(node, assign, writeExpr, maybeImplicitGlobal, partial, init) {
-
- // because Array element may be null
- if (!node || node.type !== Syntax.Identifier) {
- return;
- }
-
- // Specially handle like `this`.
- if (node.name === "super") {
- return;
- }
-
- const ref = new Reference(node, this, assign || Reference.READ, writeExpr, maybeImplicitGlobal, !!partial, !!init);
-
- this.references.push(ref);
- this.__left.push(ref);
- }
-
- __detectEval() {
- let current = this;
-
- this.directCallToEvalScope = true;
- do {
- current.dynamic = true;
- current = current.upper;
- } while (current);
- }
-
- __detectThis() {
- this.thisFound = true;
- }
-
- __isClosed() {
- return this.__left === null;
- }
-
- /**
- * returns resolved {Reference}
- * @method Scope#resolve
- * @param {Espree.Identifier} ident - identifier to be resolved.
- * @returns {Reference} reference
- */
- resolve(ident) {
- let ref, i, iz;
-
- assert(this.__isClosed(), "Scope should be closed.");
- assert(ident.type === Syntax.Identifier, "Target should be identifier.");
- for (i = 0, iz = this.references.length; i < iz; ++i) {
- ref = this.references[i];
- if (ref.identifier === ident) {
- return ref;
- }
- }
- return null;
- }
-
- /**
- * returns this scope is static
- * @method Scope#isStatic
- * @returns {boolean} static
- */
- isStatic() {
- return !this.dynamic;
- }
-
- /**
- * returns this scope has materialized arguments
- * @method Scope#isArgumentsMaterialized
- * @returns {boolean} arguemnts materialized
- */
- isArgumentsMaterialized() { // eslint-disable-line class-methods-use-this
- return true;
- }
-
- /**
- * returns this scope has materialized `this` reference
- * @method Scope#isThisMaterialized
- * @returns {boolean} this materialized
- */
- isThisMaterialized() { // eslint-disable-line class-methods-use-this
- return true;
- }
-
- isUsedName(name) {
- if (this.set.has(name)) {
- return true;
- }
- for (let i = 0, iz = this.through.length; i < iz; ++i) {
- if (this.through[i].identifier.name === name) {
- return true;
- }
- }
- return false;
- }
-}
-
-class GlobalScope extends Scope {
- constructor(scopeManager, block) {
- super(scopeManager, "global", null, block, false);
- this.implicit = {
- set: new Map(),
- variables: [],
-
- /**
- * List of {@link Reference}s that are left to be resolved (i.e. which
- * need to be linked to the variable they refer to).
- * @member {Reference[]} Scope#implicit#left
- */
- left: []
- };
- }
-
- __close(scopeManager) {
- const implicit = [];
-
- for (let i = 0, iz = this.__left.length; i < iz; ++i) {
- const ref = this.__left[i];
-
- if (ref.__maybeImplicitGlobal && !this.set.has(ref.identifier.name)) {
- implicit.push(ref.__maybeImplicitGlobal);
- }
- }
-
- // create an implicit global variable from assignment expression
- for (let i = 0, iz = implicit.length; i < iz; ++i) {
- const info = implicit[i];
-
- this.__defineImplicit(info.pattern,
- new Definition(
- Variable.ImplicitGlobalVariable,
- info.pattern,
- info.node,
- null,
- null,
- null
- ));
-
- }
-
- this.implicit.left = this.__left;
-
- return super.__close(scopeManager);
- }
-
- __defineImplicit(node, def) {
- if (node && node.type === Syntax.Identifier) {
- this.__defineGeneric(
- node.name,
- this.implicit.set,
- this.implicit.variables,
- node,
- def
- );
- }
- }
-}
-
-class ModuleScope extends Scope {
- constructor(scopeManager, upperScope, block) {
- super(scopeManager, "module", upperScope, block, false);
- }
-}
-
-class FunctionExpressionNameScope extends Scope {
- constructor(scopeManager, upperScope, block) {
- super(scopeManager, "function-expression-name", upperScope, block, false);
- this.__define(block.id,
- new Definition(
- Variable.FunctionName,
- block.id,
- block,
- null,
- null,
- null
- ));
- this.functionExpressionScope = true;
- }
-}
-
-class CatchScope extends Scope {
- constructor(scopeManager, upperScope, block) {
- super(scopeManager, "catch", upperScope, block, false);
- }
-}
-
-class WithScope extends Scope {
- constructor(scopeManager, upperScope, block) {
- super(scopeManager, "with", upperScope, block, false);
- }
-
- __close(scopeManager) {
- if (this.__shouldStaticallyClose(scopeManager)) {
- return super.__close(scopeManager);
- }
-
- for (let i = 0, iz = this.__left.length; i < iz; ++i) {
- const ref = this.__left[i];
-
- ref.tainted = true;
- this.__delegateToUpperScope(ref);
- }
- this.__left = null;
-
- return this.upper;
- }
-}
-
-class BlockScope extends Scope {
- constructor(scopeManager, upperScope, block) {
- super(scopeManager, "block", upperScope, block, false);
- }
-}
-
-class SwitchScope extends Scope {
- constructor(scopeManager, upperScope, block) {
- super(scopeManager, "switch", upperScope, block, false);
- }
-}
-
-class FunctionScope extends Scope {
- constructor(scopeManager, upperScope, block, isMethodDefinition) {
- super(scopeManager, "function", upperScope, block, isMethodDefinition);
-
- // section 9.2.13, FunctionDeclarationInstantiation.
- // NOTE Arrow functions never have an arguments objects.
- if (this.block.type !== Syntax.ArrowFunctionExpression) {
- this.__defineArguments();
- }
- }
-
- isArgumentsMaterialized() {
-
- // TODO(Constellation)
- // We can more aggressive on this condition like this.
- //
- // function t() {
- // // arguments of t is always hidden.
- // function arguments() {
- // }
- // }
- if (this.block.type === Syntax.ArrowFunctionExpression) {
- return false;
- }
-
- if (!this.isStatic()) {
- return true;
- }
-
- const variable = this.set.get("arguments");
-
- assert(variable, "Always have arguments variable.");
- return variable.tainted || variable.references.length !== 0;
- }
-
- isThisMaterialized() {
- if (!this.isStatic()) {
- return true;
- }
- return this.thisFound;
- }
-
- __defineArguments() {
- this.__defineGeneric(
- "arguments",
- this.set,
- this.variables,
- null,
- null
- );
- this.taints.set("arguments", true);
- }
-
- // References in default parameters isn't resolved to variables which are in their function body.
- // const x = 1
- // function f(a = x) { // This `x` is resolved to the `x` in the outer scope.
- // const x = 2
- // console.log(a)
- // }
- __isValidResolution(ref, variable) {
-
- // If `options.nodejsScope` is true, `this.block` becomes a Program node.
- if (this.block.type === "Program") {
- return true;
- }
-
- const bodyStart = this.block.body.range[0];
-
- // It's invalid resolution in the following case:
- return !(
- variable.scope === this &&
- ref.identifier.range[0] < bodyStart && // the reference is in the parameter part.
- variable.defs.every(d => d.name.range[0] >= bodyStart) // the variable is in the body.
- );
- }
-}
-
-class ForScope extends Scope {
- constructor(scopeManager, upperScope, block) {
- super(scopeManager, "for", upperScope, block, false);
- }
-}
-
-class ClassScope extends Scope {
- constructor(scopeManager, upperScope, block) {
- super(scopeManager, "class", upperScope, block, false);
- }
-}
-
-module.exports = {
- Scope,
- GlobalScope,
- ModuleScope,
- FunctionExpressionNameScope,
- CatchScope,
- WithScope,
- BlockScope,
- SwitchScope,
- FunctionScope,
- ForScope,
- ClassScope
-};
-
-/* vim: set sw=4 ts=4 et tw=80 : */
projects / dotfiles / .git / blobdiff