/*
Copyright (C) 2012-2013 Yusuke Suzuki <utatane.tea@gmail.com>
Copyright (C) 2012 Ariya Hidayat <ariya.hidayat@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.
*/
/*jslint vars:false, bitwise:true*/
/*jshint indent:4*/
/*global exports:true*/
(function clone(exports) {
'use strict';
var Syntax,
VisitorOption,
VisitorKeys,
BREAK,
SKIP,
REMOVE;
function deepCopy(obj) {
var ret = {}, key, val;
for (key in obj) {
if (obj.hasOwnProperty(key)) {
val = obj[key];
if (typeof val === 'object' && val !== null) {
ret[key] = deepCopy(val);
} else {
ret[key] = val;
}
}
}
return ret;
}
// based on LLVM libc++ upper_bound / lower_bound
// MIT License
function upperBound(array, func) {
var diff, len, i, current;
len = array.length;
i = 0;
while (len) {
diff = len >>> 1;
current = i + diff;
if (func(array[current])) {
len = diff;
} else {
i = current + 1;
len -= diff + 1;
}
}
return i;
}
Syntax = {
AssignmentExpression: 'AssignmentExpression',
AssignmentPattern: 'AssignmentPattern',
ArrayExpression: 'ArrayExpression',
ArrayPattern: 'ArrayPattern',
ArrowFunctionExpression: 'ArrowFunctionExpression',
AwaitExpression: 'AwaitExpression', // CAUTION: It's deferred to ES7.
BlockStatement: 'BlockStatement',
BinaryExpression: 'BinaryExpression',
BreakStatement: 'BreakStatement',
CallExpression: 'CallExpression',
CatchClause: 'CatchClause',
ChainExpression: 'ChainExpression',
ClassBody: 'ClassBody',
ClassDeclaration: 'ClassDeclaration',
ClassExpression: 'ClassExpression',
ComprehensionBlock: 'ComprehensionBlock', // CAUTION: It's deferred to ES7.
ComprehensionExpression: 'ComprehensionExpression', // CAUTION: It's deferred to ES7.
ConditionalExpression: 'ConditionalExpression',
ContinueStatement: 'ContinueStatement',
DebuggerStatement: 'DebuggerStatement',
DirectiveStatement: 'DirectiveStatement',
DoWhileStatement: 'DoWhileStatement',
EmptyStatement: 'EmptyStatement',
ExportAllDeclaration: 'ExportAllDeclaration',
ExportDefaultDeclaration: 'ExportDefaultDeclaration',
ExportNamedDeclaration: 'ExportNamedDeclaration',
ExportSpecifier: 'ExportSpecifier',
ExpressionStatement: 'ExpressionStatement',
ForStatement: 'ForStatement',
ForInStatement: 'ForInStatement',
ForOfStatement: 'ForOfStatement',
FunctionDeclaration: 'FunctionDeclaration',
FunctionExpression: 'FunctionExpression',
GeneratorExpression: 'GeneratorExpression', // CAUTION: It's deferred to ES7.
Identifier: 'Identifier',
IfStatement: 'IfStatement',
ImportExpression: 'ImportExpression',
ImportDeclaration: 'ImportDeclaration',
ImportDefaultSpecifier: 'ImportDefaultSpecifier',
ImportNamespaceSpecifier: 'ImportNamespaceSpecifier',
ImportSpecifier: 'ImportSpecifier',
Literal: 'Literal',
LabeledStatement: 'LabeledStatement',
LogicalExpression: 'LogicalExpression',
MemberExpression: 'MemberExpression',
MetaProperty: 'MetaProperty',
MethodDefinition: 'MethodDefinition',
ModuleSpecifier: 'ModuleSpecifier',
NewExpression: 'NewExpression',
ObjectExpression: 'ObjectExpression',
ObjectPattern: 'ObjectPattern',
PrivateIdentifier: 'PrivateIdentifier',
Program: 'Program',
Property: 'Property',
PropertyDefinition: 'PropertyDefinition',
RestElement: 'RestElement',
ReturnStatement: 'ReturnStatement',
SequenceExpression: 'SequenceExpression',
SpreadElement: 'SpreadElement',
Super: 'Super',
SwitchStatement: 'SwitchStatement',
SwitchCase: 'SwitchCase',
TaggedTemplateExpression: 'TaggedTemplateExpression',
TemplateElement: 'TemplateElement',
TemplateLiteral: 'TemplateLiteral',
ThisExpression: 'ThisExpression',
ThrowStatement: 'ThrowStatement',
TryStatement: 'TryStatement',
UnaryExpression: 'UnaryExpression',
UpdateExpression: 'UpdateExpression',
VariableDeclaration: 'VariableDeclaration',
VariableDeclarator: 'VariableDeclarator',
WhileStatement: 'WhileStatement',
WithStatement: 'WithStatement',
YieldExpression: 'YieldExpression'
};
VisitorKeys = {
AssignmentExpression: ['left', 'right'],
AssignmentPattern: ['left', 'right'],
ArrayExpression: ['elements'],
ArrayPattern: ['elements'],
ArrowFunctionExpression: ['params', 'body'],
AwaitExpression: ['argument'], // CAUTION: It's deferred to ES7.
BlockStatement: ['body'],
BinaryExpression: ['left', 'right'],
BreakStatement: ['label'],
CallExpression: ['callee', 'arguments'],
CatchClause: ['param', 'body'],
ChainExpression: ['expression'],
ClassBody: ['body'],
ClassDeclaration: ['id', 'superClass', 'body'],
ClassExpression: ['id', 'superClass', 'body'],
ComprehensionBlock: ['left', 'right'], // CAUTION: It's deferred to ES7.
ComprehensionExpression: ['blocks', 'filter', 'body'], // CAUTION: It's deferred to ES7.
ConditionalExpression: ['test', 'consequent', 'alternate'],
ContinueStatement: ['label'],
DebuggerStatement: [],
DirectiveStatement: [],
DoWhileStatement: ['body', 'test'],
EmptyStatement: [],
ExportAllDeclaration: ['source'],
ExportDefaultDeclaration: ['declaration'],
ExportNamedDeclaration: ['declaration', 'specifiers', 'source'],
ExportSpecifier: ['exported', 'local'],
ExpressionStatement: ['expression'],
ForStatement: ['init', 'test', 'update', 'body'],
ForInStatement: ['left', 'right', 'body'],
ForOfStatement: ['left', 'right', 'body'],
FunctionDeclaration: ['id', 'params', 'body'],
FunctionExpression: ['id', 'params', 'body'],
GeneratorExpression: ['blocks', 'filter', 'body'], // CAUTION: It's deferred to ES7.
Identifier: [],
IfStatement: ['test', 'consequent', 'alternate'],
ImportExpression: ['source'],
ImportDeclaration: ['specifiers', 'source'],
ImportDefaultSpecifier: ['local'],
ImportNamespaceSpecifier: ['local'],
ImportSpecifier: ['imported', 'local'],
Literal: [],
LabeledStatement: ['label', 'body'],
LogicalExpression: ['left', 'right'],
MemberExpression: ['object', 'property'],
MetaProperty: ['meta', 'property'],
MethodDefinition: ['key', 'value'],
ModuleSpecifier: [],
NewExpression: ['callee', 'arguments'],
ObjectExpression: ['properties'],
ObjectPattern: ['properties'],
PrivateIdentifier: [],
Program: ['body'],
Property: ['key', 'value'],
PropertyDefinition: ['key', 'value'],
RestElement: [ 'argument' ],
ReturnStatement: ['argument'],
SequenceExpression: ['expressions'],
SpreadElement: ['argument'],
Super: [],
SwitchStatement: ['discriminant', 'cases'],
SwitchCase: ['test', 'consequent'],
TaggedTemplateExpression: ['tag', 'quasi'],
TemplateElement: [],
TemplateLiteral: ['quasis', 'expressions'],
ThisExpression: [],
ThrowStatement: ['argument'],
TryStatement: ['block', 'handler', 'finalizer'],
UnaryExpression: ['argument'],
UpdateExpression: ['argument'],
VariableDeclaration: ['declarations'],
VariableDeclarator: ['id', 'init'],
WhileStatement: ['test', 'body'],
WithStatement: ['object', 'body'],
YieldExpression: ['argument']
};
// unique id
BREAK = {};
SKIP = {};
REMOVE = {};
VisitorOption = {
Break: BREAK,
Skip: SKIP,
Remove: REMOVE
};
function Reference(parent, key) {
this.parent = parent;
this.key = key;
}
Reference.prototype.replace = function replace(node) {
this.parent[this.key] = node;
};
Reference.prototype.remove = function remove() {
if (Array.isArray(this.parent)) {
this.parent.splice(this.key, 1);
return true;
} else {
this.replace(null);
return false;
}
};
function Element(node, path, wrap, ref) {
this.node = node;
this.path = path;
this.wrap = wrap;
this.ref = ref;
}
function Controller() { }
// API:
// return property path array from root to current node
Controller.prototype.path = function path() {
var i, iz, j, jz, result, element;
function addToPath(result, path) {
if (Array.isArray(path)) {
for (j = 0, jz = path.length; j < jz; ++j) {
result.push(path[j]);
}
} else {
result.push(path);
}
}
// root node
if (!this.__current.path) {
return null;
}
// first node is sentinel, second node is root element
result = [];
for (i = 2, iz = this.__leavelist.length; i < iz; ++i) {
element = this.__leavelist[i];
addToPath(result, element.path);
}
addToPath(result, this.__current.path);
return result;
};
// API:
// return type of current node
Controller.prototype.type = function () {
var node = this.current();
return node.type || this.__current.wrap;
};
// API:
// return array of parent elements
Controller.prototype.parents = function parents() {
var i, iz, result;
// first node is sentinel
result = [];
for (i = 1, iz = this.__leavelist.length; i < iz; ++i) {
result.push(this.__leavelist[i].node);
}
return result;
};
// API:
// return current node
Controller.prototype.current = function current() {
return this.__current.node;
};
Controller.prototype.__execute = function __execute(callback, element) {
var previous, result;
result = undefined;
previous = this.__current;
this.__current = element;
this.__state = null;
if (callback) {
result = callback.call(this, element.node, this.__leavelist[this.__leavelist.length - 1].node);
}
this.__current = previous;
return result;
};
// API:
// notify control skip / break
Controller.prototype.notify = function notify(flag) {
this.__state = flag;
};
// API:
// skip child nodes of current node
Controller.prototype.skip = function () {
this.notify(SKIP);
};
// API:
// break traversals
Controller.prototype['break'] = function () {
this.notify(BREAK);
};
// API:
// remove node
Controller.prototype.remove = function () {
this.notify(REMOVE);
};
Controller.prototype.__initialize = function(root, visitor) {
this.visitor = visitor;
this.root = root;
this.__worklist = [];
this.__leavelist = [];
this.__current = null;
this.__state = null;
this.__fallback = null;
if (visitor.fallback === 'iteration') {
this.__fallback = Object.keys;
} else if (typeof visitor.fallback === 'function') {
this.__fallback = visitor.fallback;
}
this.__keys = VisitorKeys;
if (visitor.keys) {
this.__keys = Object.assign(Object.create(this.__keys), visitor.keys);
}
};
function isNode(node) {
if (node == null) {
return false;
}
return typeof node === 'object' && typeof node.type === 'string';
}
function isProperty(nodeType, key) {
return (nodeType === Syntax.ObjectExpression || nodeType === Syntax.ObjectPattern) && 'properties' === key;
}
function candidateExistsInLeaveList(leavelist, candidate) {
for (var i = leavelist.length - 1; i >= 0; --i) {
if (leavelist[i].node === candidate) {
return true;
}
}
return false;
}
Controller.prototype.traverse = function traverse(root, visitor) {
var worklist,
leavelist,
element,
node,
nodeType,
ret,
key,
current,
current2,
candidates,
candidate,
sentinel;
this.__initialize(root, visitor);
sentinel = {};
// reference
worklist = this.__worklist;
leavelist = this.__leavelist;
// initialize
worklist.push(new Element(root, null, null, null));
leavelist.push(new Element(null, null, null, null));
while (worklist.length) {
element = worklist.pop();
if (element === sentinel) {
element = leavelist.pop();
ret = this.__execute(visitor.leave, element);
if (this.__state === BREAK || ret === BREAK) {
return;
}
continue;
}
if (element.node) {
ret = this.__execute(visitor.enter, element);
if (this.__state === BREAK || ret === BREAK) {
return;
}
worklist.push(sentinel);
leavelist.push(element);
if (this.__state === SKIP || ret === SKIP) {
continue;
}
node = element.node;
nodeType = node.type || element.wrap;
candidates = this.__keys[nodeType];
if (!candidates) {
if (this.__fallback) {
candidates = this.__fallback(node);
} else {
throw new Error('Unknown node type ' + nodeType + '.');
}
}
current = candidates.length;
while ((current -= 1) >= 0) {
key = candidates[current];
candidate = node[key];
if (!candidate) {
continue;
}
if (Array.isArray(candidate)) {
current2 = candidate.length;
while ((current2 -= 1) >= 0) {
if (!candidate[current2]) {
continue;
}
if (candidateExistsInLeaveList(leavelist, candidate[current2])) {
continue;
}
if (isProperty(nodeType, candidates[current])) {
element = new Element(candidate[current2], [key, current2], 'Property', null);
} else if (isNode(candidate[current2])) {
element = new Element(candidate[current2], [key, current2], null, null);
} else {
continue;
}
worklist.push(element);
}
} else if (isNode(candidate)) {
if (candidateExistsInLeaveList(leavelist, candidate)) {
continue;
}
worklist.push(new Element(candidate, key, null, null));
}
}
}
}
};
Controller.prototype.replace = function replace(root, visitor) {
var worklist,
leavelist,
node,
nodeType,
target,
element,
current,
current2,
candidates,
candidate,
sentinel,
outer,
key;
function removeElem(element) {
var i,
key,
nextElem,
parent;
if (element.ref.remove()) {
// When the reference is an element of an array.
key = element.ref.key;
parent = element.ref.parent;
// If removed from array, then decrease following items' keys.
i = worklist.length;
while (i--) {
nextElem = worklist[i];
if (nextElem.ref && nextElem.ref.parent === parent) {
if (nextElem.ref.key < key) {
break;
}
--nextElem.ref.key;
}
}
}
}
this.__initialize(root, visitor);
sentinel = {};
// reference
worklist = this.__worklist;
leavelist = this.__leavelist;
// initialize
outer = {
root: root
};
element = new Element(root, null, null, new Reference(outer, 'root'));
worklist.push(element);
leavelist.push(element);
while (worklist.length) {
element = worklist.pop();
if (element === sentinel) {
element = leavelist.pop();
target = this.__execute(visitor.leave, element);
// node may be replaced with null,
// so distinguish between undefined and null in this place
if (target !== undefined && target !== BREAK && target !== SKIP && target !== REMOVE) {
// replace
element.ref.replace(target);
}
if (this.__state === REMOVE || target === REMOVE) {
removeElem(element);
}
if (this.__state === BREAK || target === BREAK) {
return outer.root;
}
continue;
}
target = this.__execute(visitor.enter, element);
// node may be replaced with null,
// so distinguish between undefined and null in this place
if (target !== undefined && target !== BREAK && target !== SKIP && target !== REMOVE) {
// replace
element.ref.replace(target);
element.node = target;
}
if (this.__state === REMOVE || target === REMOVE) {
removeElem(element);
element.node = null;
}
if (this.__state === BREAK || target === BREAK) {
return outer.root;
}
// node may be null
node = element.node;
if (!node) {
continue;
}
worklist.push(sentinel);
leavelist.push(element);
if (this.__state === SKIP || target === SKIP) {
continue;
}
nodeType = node.type || element.wrap;
candidates = this.__keys[nodeType];
if (!candidates) {
if (this.__fallback) {
candidates = this.__fallback(node);
} else {
throw new Error('Unknown node type ' + nodeType + '.');
}
}
current = candidates.length;
while ((current -= 1) >= 0) {
key = candidates[current];
candidate = node[key];
if (!candidate) {
continue;
}
if (Array.isArray(candidate)) {
current2 = candidate.length;
while ((current2 -= 1) >= 0) {
if (!candidate[current2]) {
continue;
}
if (isProperty(nodeType, candidates[current])) {
element = new Element(candidate[current2], [key, current2], 'Property', new Reference(candidate, current2));
} else if (isNode(candidate[current2])) {
element = new Element(candidate[current2], [key, current2], null, new Reference(candidate, current2));
} else {
continue;
}
worklist.push(element);
}
} else if (isNode(candidate)) {
worklist.push(new Element(candidate, key, null, new Reference(node, key)));
}
}
}
return outer.root;
};
function traverse(root, visitor) {
var controller = new Controller();
return controller.traverse(root, visitor);
}
function replace(root, visitor) {
var controller = new Controller();
return controller.replace(root, visitor);
}
function extendCommentRange(comment, tokens) {
var target;
target = upperBound(tokens, function search(token) {
return token.range[0] > comment.range[0];
});
comment.extendedRange = [comment.range[0], comment.range[1]];
if (target !== tokens.length) {
comment.extendedRange[1] = tokens[target].range[0];
}
target -= 1;
if (target >= 0) {
comment.extendedRange[0] = tokens[target].range[1];
}
return comment;
}
function attachComments(tree, providedComments, tokens) {
// At first, we should calculate extended comment ranges.
var comments = [], comment, len, i, cursor;
if (!tree.range) {
throw new Error('attachComments needs range information');
}
// tokens array is empty, we attach comments to tree as 'leadingComments'
if (!tokens.length) {
if (providedComments.length) {
for (i = 0, len = providedComments.length; i < len; i += 1) {
comment = deepCopy(providedComments[i]);
comment.extendedRange = [0, tree.range[0]];
comments.push(comment);
}
tree.leadingComments = comments;
}
return tree;
}
for (i = 0, len = providedComments.length; i < len; i += 1) {
comments.push(extendCommentRange(deepCopy(providedComments[i]), tokens));
}
// This is based on John Freeman's implementation.
cursor = 0;
traverse(tree, {
enter: function (node) {
var comment;
while (cursor < comments.length) {
comment = comments[cursor];
if (comment.extendedRange[1] > node.range[0]) {
break;
}
if (comment.extendedRange[1] === node.range[0]) {
if (!node.leadingComments) {
node.leadingComments = [];
}
node.leadingComments.push(comment);
comments.splice(cursor, 1);
} else {
cursor += 1;
}
}
// already out of owned node
if (cursor === comments.length) {
return VisitorOption.Break;
}
if (comments[cursor].extendedRange[0] > node.range[1]) {
return VisitorOption.Skip;
}
}
});
cursor = 0;
traverse(tree, {
leave: function (node) {
var comment;
while (cursor < comments.length) {
comment = comments[cursor];
if (node.range[1] < comment.extendedRange[0]) {
break;
}
if (node.range[1] === comment.extendedRange[0]) {
if (!node.trailingComments) {
node.trailingComments = [];
}
node.trailingComments.push(comment);
comments.splice(cursor, 1);
} else {
cursor += 1;
}
}
// already out of owned node
if (cursor === comments.length) {
return VisitorOption.Break;
}
if (comments[cursor].extendedRange[0] > node.range[1]) {
return VisitorOption.Skip;
}
}
});
return tree;
}
exports.Syntax = Syntax;
exports.traverse = traverse;
exports.replace = replace;
exports.attachComments = attachComments;
exports.VisitorKeys = VisitorKeys;
exports.VisitorOption = VisitorOption;
exports.Controller = Controller;
exports.cloneEnvironment = function () { return clone({}); };
return exports;
}(exports));
/* vim: set sw=4 ts=4 et tw=80 : */
