lix-website/themes/lix/assets/bootstrap/node_modules/chainsaw/index.js
2024-04-26 22:49:34 -06:00

146 lines
3.6 KiB
JavaScript
Executable file

var Traverse = require('traverse');
var EventEmitter = require('events').EventEmitter;
module.exports = Chainsaw;
function Chainsaw (builder) {
var saw = Chainsaw.saw(builder, {});
var r = builder.call(saw.handlers, saw);
if (r !== undefined) saw.handlers = r;
saw.record();
return saw.chain();
};
Chainsaw.light = function ChainsawLight (builder) {
var saw = Chainsaw.saw(builder, {});
var r = builder.call(saw.handlers, saw);
if (r !== undefined) saw.handlers = r;
return saw.chain();
};
Chainsaw.saw = function (builder, handlers) {
var saw = new EventEmitter;
saw.handlers = handlers;
saw.actions = [];
saw.chain = function () {
var ch = Traverse(saw.handlers).map(function (node) {
if (this.isRoot) return node;
var ps = this.path;
if (typeof node === 'function') {
this.update(function () {
saw.actions.push({
path : ps,
args : [].slice.call(arguments)
});
return ch;
});
}
});
process.nextTick(function () {
saw.emit('begin');
saw.next();
});
return ch;
};
saw.pop = function () {
return saw.actions.shift();
};
saw.next = function () {
var action = saw.pop();
if (!action) {
saw.emit('end');
}
else if (!action.trap) {
var node = saw.handlers;
action.path.forEach(function (key) { node = node[key] });
node.apply(saw.handlers, action.args);
}
};
saw.nest = function (cb) {
var args = [].slice.call(arguments, 1);
var autonext = true;
if (typeof cb === 'boolean') {
var autonext = cb;
cb = args.shift();
}
var s = Chainsaw.saw(builder, {});
var r = builder.call(s.handlers, s);
if (r !== undefined) s.handlers = r;
// If we are recording...
if ("undefined" !== typeof saw.step) {
// ... our children should, too
s.record();
}
cb.apply(s.chain(), args);
if (autonext !== false) s.on('end', saw.next);
};
saw.record = function () {
upgradeChainsaw(saw);
};
['trap', 'down', 'jump'].forEach(function (method) {
saw[method] = function () {
throw new Error("To use the trap, down and jump features, please "+
"call record() first to start recording actions.");
};
});
return saw;
};
function upgradeChainsaw(saw) {
saw.step = 0;
// override pop
saw.pop = function () {
return saw.actions[saw.step++];
};
saw.trap = function (name, cb) {
var ps = Array.isArray(name) ? name : [name];
saw.actions.push({
path : ps,
step : saw.step,
cb : cb,
trap : true
});
};
saw.down = function (name) {
var ps = (Array.isArray(name) ? name : [name]).join('/');
var i = saw.actions.slice(saw.step).map(function (x) {
if (x.trap && x.step <= saw.step) return false;
return x.path.join('/') == ps;
}).indexOf(true);
if (i >= 0) saw.step += i;
else saw.step = saw.actions.length;
var act = saw.actions[saw.step - 1];
if (act && act.trap) {
// It's a trap!
saw.step = act.step;
act.cb();
}
else saw.next();
};
saw.jump = function (step) {
saw.step = step;
saw.next();
};
};