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JavaScript

6 years ago
var traverse = module.exports = function (obj) {
return new Traverse(obj);
};
function Traverse (obj) {
this.value = obj;
}
Traverse.prototype.get = function (ps) {
var node = this.value;
for (var i = 0; i < ps.length; i ++) {
var key = ps[i];
if (!node || !hasOwnProperty.call(node, key)) {
node = undefined;
break;
}
node = node[key];
}
return node;
};
Traverse.prototype.has = function (ps) {
var node = this.value;
for (var i = 0; i < ps.length; i ++) {
var key = ps[i];
if (!node || !hasOwnProperty.call(node, key)) {
return false;
}
node = node[key];
}
return true;
};
Traverse.prototype.set = function (ps, value) {
var node = this.value;
for (var i = 0; i < ps.length - 1; i ++) {
var key = ps[i];
if (!hasOwnProperty.call(node, key)) node[key] = {};
node = node[key];
}
node[ps[i]] = value;
return value;
};
Traverse.prototype.map = function (cb) {
return walk(this.value, cb, true);
};
Traverse.prototype.forEach = function (cb) {
this.value = walk(this.value, cb, false);
return this.value;
};
Traverse.prototype.reduce = function (cb, init) {
var skip = arguments.length === 1;
var acc = skip ? this.value : init;
this.forEach(function (x) {
if (!this.isRoot || !skip) {
acc = cb.call(this, acc, x);
}
});
return acc;
};
Traverse.prototype.paths = function () {
var acc = [];
this.forEach(function (x) {
acc.push(this.path);
});
return acc;
};
Traverse.prototype.nodes = function () {
var acc = [];
this.forEach(function (x) {
acc.push(this.node);
});
return acc;
};
Traverse.prototype.clone = function () {
var parents = [], nodes = [];
return (function clone (src) {
for (var i = 0; i < parents.length; i++) {
if (parents[i] === src) {
return nodes[i];
}
}
if (typeof src === 'object' && src !== null) {
var dst = copy(src);
parents.push(src);
nodes.push(dst);
forEach(objectKeys(src), function (key) {
dst[key] = clone(src[key]);
});
parents.pop();
nodes.pop();
return dst;
}
else {
return src;
}
})(this.value);
};
function walk (root, cb, immutable) {
var path = [];
var parents = [];
var alive = true;
return (function walker (node_) {
var node = immutable ? copy(node_) : node_;
var modifiers = {};
var keepGoing = true;
var state = {
node : node,
node_ : node_,
path : [].concat(path),
parent : parents[parents.length - 1],
parents : parents,
key : path.slice(-1)[0],
isRoot : path.length === 0,
level : path.length,
circular : null,
update : function (x, stopHere) {
if (!state.isRoot) {
state.parent.node[state.key] = x;
}
state.node = x;
if (stopHere) keepGoing = false;
},
'delete' : function (stopHere) {
delete state.parent.node[state.key];
if (stopHere) keepGoing = false;
},
remove : function (stopHere) {
if (isArray(state.parent.node)) {
state.parent.node.splice(state.key, 1);
}
else {
delete state.parent.node[state.key];
}
if (stopHere) keepGoing = false;
},
keys : null,
before : function (f) { modifiers.before = f },
after : function (f) { modifiers.after = f },
pre : function (f) { modifiers.pre = f },
post : function (f) { modifiers.post = f },
stop : function () { alive = false },
block : function () { keepGoing = false }
};
if (!alive) return state;
function updateState() {
if (typeof state.node === 'object' && state.node !== null) {
if (!state.keys || state.node_ !== state.node) {
state.keys = objectKeys(state.node)
}
state.isLeaf = state.keys.length == 0;
for (var i = 0; i < parents.length; i++) {
if (parents[i].node_ === node_) {
state.circular = parents[i];
break;
}
}
}
else {
state.isLeaf = true;
state.keys = null;
}
state.notLeaf = !state.isLeaf;
state.notRoot = !state.isRoot;
}
updateState();
// use return values to update if defined
var ret = cb.call(state, state.node);
if (ret !== undefined && state.update) state.update(ret);
if (modifiers.before) modifiers.before.call(state, state.node);
if (!keepGoing) return state;
if (typeof state.node == 'object'
&& state.node !== null && !state.circular) {
parents.push(state);
updateState();
forEach(state.keys, function (key, i) {
path.push(key);
if (modifiers.pre) modifiers.pre.call(state, state.node[key], key);
var child = walker(state.node[key]);
if (immutable && hasOwnProperty.call(state.node, key)) {
state.node[key] = child.node;
}
child.isLast = i == state.keys.length - 1;
child.isFirst = i == 0;
if (modifiers.post) modifiers.post.call(state, child);
path.pop();
});
parents.pop();
}
if (modifiers.after) modifiers.after.call(state, state.node);
return state;
})(root).node;
}
function copy (src) {
if (typeof src === 'object' && src !== null) {
var dst;
if (isArray(src)) {
dst = [];
}
else if (isDate(src)) {
dst = new Date(src.getTime ? src.getTime() : src);
}
else if (isRegExp(src)) {
dst = new RegExp(src);
}
else if (isError(src)) {
dst = { message: src.message };
}
else if (isBoolean(src)) {
dst = new Boolean(src);
}
else if (isNumber(src)) {
dst = new Number(src);
}
else if (isString(src)) {
dst = new String(src);
}
else if (Object.create && Object.getPrototypeOf) {
dst = Object.create(Object.getPrototypeOf(src));
}
else if (src.constructor === Object) {
dst = {};
}
else {
var proto =
(src.constructor && src.constructor.prototype)
|| src.__proto__
|| {}
;
var T = function () {};
T.prototype = proto;
dst = new T;
}
forEach(objectKeys(src), function (key) {
dst[key] = src[key];
});
return dst;
}
else return src;
}
var objectKeys = Object.keys || function keys (obj) {
var res = [];
for (var key in obj) res.push(key)
return res;
};
function toS (obj) { return Object.prototype.toString.call(obj) }
function isDate (obj) { return toS(obj) === '[object Date]' }
function isRegExp (obj) { return toS(obj) === '[object RegExp]' }
function isError (obj) { return toS(obj) === '[object Error]' }
function isBoolean (obj) { return toS(obj) === '[object Boolean]' }
function isNumber (obj) { return toS(obj) === '[object Number]' }
function isString (obj) { return toS(obj) === '[object String]' }
var isArray = Array.isArray || function isArray (xs) {
return Object.prototype.toString.call(xs) === '[object Array]';
};
var forEach = function (xs, fn) {
if (xs.forEach) return xs.forEach(fn)
else for (var i = 0; i < xs.length; i++) {
fn(xs[i], i, xs);
}
};
forEach(objectKeys(Traverse.prototype), function (key) {
traverse[key] = function (obj) {
var args = [].slice.call(arguments, 1);
var t = new Traverse(obj);
return t[key].apply(t, args);
};
});
var hasOwnProperty = Object.hasOwnProperty || function (obj, key) {
return key in obj;
};