736 lines
17 KiB
JavaScript
736 lines
17 KiB
JavaScript
/*
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* lib/jsprim.js: utilities for primitive JavaScript types
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*/
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var mod_assert = require('assert-plus');
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var mod_util = require('util');
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var mod_extsprintf = require('extsprintf');
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var mod_verror = require('verror');
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var mod_jsonschema = require('json-schema');
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/*
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* Public interface
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*/
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exports.deepCopy = deepCopy;
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exports.deepEqual = deepEqual;
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exports.isEmpty = isEmpty;
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exports.hasKey = hasKey;
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exports.forEachKey = forEachKey;
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exports.pluck = pluck;
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exports.flattenObject = flattenObject;
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exports.flattenIter = flattenIter;
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exports.validateJsonObject = validateJsonObjectJS;
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exports.validateJsonObjectJS = validateJsonObjectJS;
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exports.randElt = randElt;
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exports.extraProperties = extraProperties;
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exports.mergeObjects = mergeObjects;
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exports.startsWith = startsWith;
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exports.endsWith = endsWith;
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exports.parseInteger = parseInteger;
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exports.iso8601 = iso8601;
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exports.rfc1123 = rfc1123;
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exports.parseDateTime = parseDateTime;
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exports.hrtimediff = hrtimeDiff;
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exports.hrtimeDiff = hrtimeDiff;
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exports.hrtimeAccum = hrtimeAccum;
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exports.hrtimeAdd = hrtimeAdd;
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exports.hrtimeNanosec = hrtimeNanosec;
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exports.hrtimeMicrosec = hrtimeMicrosec;
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exports.hrtimeMillisec = hrtimeMillisec;
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/*
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* Deep copy an acyclic *basic* Javascript object. This only handles basic
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* scalars (strings, numbers, booleans) and arbitrarily deep arrays and objects
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* containing these. This does *not* handle instances of other classes.
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*/
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function deepCopy(obj)
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{
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var ret, key;
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var marker = '__deepCopy';
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if (obj && obj[marker])
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throw (new Error('attempted deep copy of cyclic object'));
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if (obj && obj.constructor == Object) {
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ret = {};
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obj[marker] = true;
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for (key in obj) {
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if (key == marker)
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continue;
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ret[key] = deepCopy(obj[key]);
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}
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delete (obj[marker]);
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return (ret);
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}
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if (obj && obj.constructor == Array) {
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ret = [];
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obj[marker] = true;
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for (key = 0; key < obj.length; key++)
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ret.push(deepCopy(obj[key]));
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delete (obj[marker]);
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return (ret);
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}
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/*
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* It must be a primitive type -- just return it.
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*/
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return (obj);
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}
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function deepEqual(obj1, obj2)
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{
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if (typeof (obj1) != typeof (obj2))
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return (false);
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if (obj1 === null || obj2 === null || typeof (obj1) != 'object')
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return (obj1 === obj2);
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if (obj1.constructor != obj2.constructor)
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return (false);
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var k;
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for (k in obj1) {
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if (!obj2.hasOwnProperty(k))
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return (false);
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if (!deepEqual(obj1[k], obj2[k]))
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return (false);
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}
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for (k in obj2) {
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if (!obj1.hasOwnProperty(k))
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return (false);
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}
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return (true);
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}
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function isEmpty(obj)
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{
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var key;
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for (key in obj)
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return (false);
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return (true);
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}
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function hasKey(obj, key)
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{
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mod_assert.equal(typeof (key), 'string');
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return (Object.prototype.hasOwnProperty.call(obj, key));
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}
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function forEachKey(obj, callback)
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{
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for (var key in obj) {
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if (hasKey(obj, key)) {
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callback(key, obj[key]);
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}
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}
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}
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function pluck(obj, key)
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{
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mod_assert.equal(typeof (key), 'string');
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return (pluckv(obj, key));
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}
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function pluckv(obj, key)
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{
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if (obj === null || typeof (obj) !== 'object')
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return (undefined);
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if (obj.hasOwnProperty(key))
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return (obj[key]);
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var i = key.indexOf('.');
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if (i == -1)
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return (undefined);
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var key1 = key.substr(0, i);
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if (!obj.hasOwnProperty(key1))
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return (undefined);
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return (pluckv(obj[key1], key.substr(i + 1)));
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}
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/*
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* Invoke callback(row) for each entry in the array that would be returned by
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* flattenObject(data, depth). This is just like flattenObject(data,
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* depth).forEach(callback), except that the intermediate array is never
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* created.
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*/
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function flattenIter(data, depth, callback)
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{
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doFlattenIter(data, depth, [], callback);
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}
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function doFlattenIter(data, depth, accum, callback)
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{
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var each;
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var key;
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if (depth === 0) {
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each = accum.slice(0);
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each.push(data);
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callback(each);
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return;
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}
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mod_assert.ok(data !== null);
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mod_assert.equal(typeof (data), 'object');
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mod_assert.equal(typeof (depth), 'number');
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mod_assert.ok(depth >= 0);
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for (key in data) {
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each = accum.slice(0);
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each.push(key);
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doFlattenIter(data[key], depth - 1, each, callback);
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}
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}
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function flattenObject(data, depth)
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{
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if (depth === 0)
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return ([ data ]);
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mod_assert.ok(data !== null);
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mod_assert.equal(typeof (data), 'object');
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mod_assert.equal(typeof (depth), 'number');
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mod_assert.ok(depth >= 0);
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var rv = [];
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var key;
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for (key in data) {
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flattenObject(data[key], depth - 1).forEach(function (p) {
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rv.push([ key ].concat(p));
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});
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}
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return (rv);
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}
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function startsWith(str, prefix)
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{
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return (str.substr(0, prefix.length) == prefix);
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}
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function endsWith(str, suffix)
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{
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return (str.substr(
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str.length - suffix.length, suffix.length) == suffix);
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}
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function iso8601(d)
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{
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if (typeof (d) == 'number')
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d = new Date(d);
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mod_assert.ok(d.constructor === Date);
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return (mod_extsprintf.sprintf('%4d-%02d-%02dT%02d:%02d:%02d.%03dZ',
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d.getUTCFullYear(), d.getUTCMonth() + 1, d.getUTCDate(),
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d.getUTCHours(), d.getUTCMinutes(), d.getUTCSeconds(),
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d.getUTCMilliseconds()));
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}
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var RFC1123_MONTHS = [
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'Jan', 'Feb', 'Mar', 'Apr', 'May', 'Jun',
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'Jul', 'Aug', 'Sep', 'Oct', 'Nov', 'Dec'];
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var RFC1123_DAYS = [
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'Sun', 'Mon', 'Tue', 'Wed', 'Thu', 'Fri', 'Sat'];
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function rfc1123(date) {
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return (mod_extsprintf.sprintf('%s, %02d %s %04d %02d:%02d:%02d GMT',
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RFC1123_DAYS[date.getUTCDay()], date.getUTCDate(),
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RFC1123_MONTHS[date.getUTCMonth()], date.getUTCFullYear(),
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date.getUTCHours(), date.getUTCMinutes(),
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date.getUTCSeconds()));
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}
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/*
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* Parses a date expressed as a string, as either a number of milliseconds since
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* the epoch or any string format that Date accepts, giving preference to the
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* former where these two sets overlap (e.g., small numbers).
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*/
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function parseDateTime(str)
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{
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/*
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* This is irritatingly implicit, but significantly more concise than
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* alternatives. The "+str" will convert a string containing only a
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* number directly to a Number, or NaN for other strings. Thus, if the
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* conversion succeeds, we use it (this is the milliseconds-since-epoch
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* case). Otherwise, we pass the string directly to the Date
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* constructor to parse.
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*/
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var numeric = +str;
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if (!isNaN(numeric)) {
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return (new Date(numeric));
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} else {
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return (new Date(str));
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}
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}
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/*
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* Number.*_SAFE_INTEGER isn't present before node v0.12, so we hardcode
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* the ES6 definitions here, while allowing for them to someday be higher.
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*/
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var MAX_SAFE_INTEGER = Number.MAX_SAFE_INTEGER || 9007199254740991;
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var MIN_SAFE_INTEGER = Number.MIN_SAFE_INTEGER || -9007199254740991;
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/*
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* Default options for parseInteger().
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*/
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var PI_DEFAULTS = {
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base: 10,
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allowSign: true,
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allowPrefix: false,
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allowTrailing: false,
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allowImprecise: false,
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trimWhitespace: false,
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leadingZeroIsOctal: false
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};
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var CP_0 = 0x30;
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var CP_9 = 0x39;
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var CP_A = 0x41;
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var CP_B = 0x42;
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var CP_O = 0x4f;
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var CP_T = 0x54;
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var CP_X = 0x58;
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var CP_Z = 0x5a;
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var CP_a = 0x61;
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var CP_b = 0x62;
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var CP_o = 0x6f;
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var CP_t = 0x74;
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var CP_x = 0x78;
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var CP_z = 0x7a;
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var PI_CONV_DEC = 0x30;
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var PI_CONV_UC = 0x37;
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var PI_CONV_LC = 0x57;
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/*
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* A stricter version of parseInt() that provides options for changing what
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* is an acceptable string (for example, disallowing trailing characters).
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*/
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function parseInteger(str, uopts)
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{
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mod_assert.string(str, 'str');
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mod_assert.optionalObject(uopts, 'options');
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var baseOverride = false;
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var options = PI_DEFAULTS;
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if (uopts) {
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baseOverride = hasKey(uopts, 'base');
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options = mergeObjects(options, uopts);
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mod_assert.number(options.base, 'options.base');
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mod_assert.ok(options.base >= 2, 'options.base >= 2');
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mod_assert.ok(options.base <= 36, 'options.base <= 36');
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mod_assert.bool(options.allowSign, 'options.allowSign');
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mod_assert.bool(options.allowPrefix, 'options.allowPrefix');
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mod_assert.bool(options.allowTrailing,
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'options.allowTrailing');
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mod_assert.bool(options.allowImprecise,
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'options.allowImprecise');
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mod_assert.bool(options.trimWhitespace,
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'options.trimWhitespace');
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mod_assert.bool(options.leadingZeroIsOctal,
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'options.leadingZeroIsOctal');
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if (options.leadingZeroIsOctal) {
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mod_assert.ok(!baseOverride,
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'"base" and "leadingZeroIsOctal" are ' +
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'mutually exclusive');
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}
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}
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var c;
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var pbase = -1;
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var base = options.base;
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var start;
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var mult = 1;
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var value = 0;
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var idx = 0;
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var len = str.length;
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/* Trim any whitespace on the left side. */
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if (options.trimWhitespace) {
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while (idx < len && isSpace(str.charCodeAt(idx))) {
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++idx;
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}
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}
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/* Check the number for a leading sign. */
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if (options.allowSign) {
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if (str[idx] === '-') {
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idx += 1;
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mult = -1;
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} else if (str[idx] === '+') {
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idx += 1;
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}
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}
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/* Parse the base-indicating prefix if there is one. */
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if (str[idx] === '0') {
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if (options.allowPrefix) {
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pbase = prefixToBase(str.charCodeAt(idx + 1));
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if (pbase !== -1 && (!baseOverride || pbase === base)) {
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base = pbase;
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idx += 2;
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}
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}
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if (pbase === -1 && options.leadingZeroIsOctal) {
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base = 8;
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}
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}
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/* Parse the actual digits. */
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for (start = idx; idx < len; ++idx) {
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c = translateDigit(str.charCodeAt(idx));
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if (c !== -1 && c < base) {
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value *= base;
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value += c;
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} else {
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break;
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}
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}
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/* If we didn't parse any digits, we have an invalid number. */
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if (start === idx) {
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return (new Error('invalid number: ' + JSON.stringify(str)));
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}
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/* Trim any whitespace on the right side. */
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if (options.trimWhitespace) {
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while (idx < len && isSpace(str.charCodeAt(idx))) {
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++idx;
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}
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}
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/* Check for trailing characters. */
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if (idx < len && !options.allowTrailing) {
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return (new Error('trailing characters after number: ' +
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JSON.stringify(str.slice(idx))));
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}
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/* If our value is 0, we return now, to avoid returning -0. */
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if (value === 0) {
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return (0);
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}
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/* Calculate our final value. */
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var result = value * mult;
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/*
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* If the string represents a value that cannot be precisely represented
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* by JavaScript, then we want to check that:
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*
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* - We never increased the value past MAX_SAFE_INTEGER
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* - We don't make the result negative and below MIN_SAFE_INTEGER
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*
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* Because we only ever increment the value during parsing, there's no
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* chance of moving past MAX_SAFE_INTEGER and then dropping below it
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* again, losing precision in the process. This means that we only need
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* to do our checks here, at the end.
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*/
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if (!options.allowImprecise &&
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(value > MAX_SAFE_INTEGER || result < MIN_SAFE_INTEGER)) {
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return (new Error('number is outside of the supported range: ' +
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JSON.stringify(str.slice(start, idx))));
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}
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return (result);
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}
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/*
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* Interpret a character code as a base-36 digit.
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*/
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function translateDigit(d)
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{
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if (d >= CP_0 && d <= CP_9) {
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/* '0' to '9' -> 0 to 9 */
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return (d - PI_CONV_DEC);
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} else if (d >= CP_A && d <= CP_Z) {
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/* 'A' - 'Z' -> 10 to 35 */
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return (d - PI_CONV_UC);
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} else if (d >= CP_a && d <= CP_z) {
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/* 'a' - 'z' -> 10 to 35 */
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return (d - PI_CONV_LC);
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} else {
|
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/* Invalid character code */
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return (-1);
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}
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}
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|
|
|
|
/*
|
|
* Test if a value matches the ECMAScript definition of trimmable whitespace.
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*/
|
|
function isSpace(c)
|
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{
|
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return (c === 0x20) ||
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(c >= 0x0009 && c <= 0x000d) ||
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(c === 0x00a0) ||
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(c === 0x1680) ||
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(c === 0x180e) ||
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(c >= 0x2000 && c <= 0x200a) ||
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(c === 0x2028) ||
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(c === 0x2029) ||
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(c === 0x202f) ||
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(c === 0x205f) ||
|
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(c === 0x3000) ||
|
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(c === 0xfeff);
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}
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|
|
|
|
/*
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* Determine which base a character indicates (e.g., 'x' indicates hex).
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*/
|
|
function prefixToBase(c)
|
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{
|
|
if (c === CP_b || c === CP_B) {
|
|
/* 0b/0B (binary) */
|
|
return (2);
|
|
} else if (c === CP_o || c === CP_O) {
|
|
/* 0o/0O (octal) */
|
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return (8);
|
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} else if (c === CP_t || c === CP_T) {
|
|
/* 0t/0T (decimal) */
|
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return (10);
|
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} else if (c === CP_x || c === CP_X) {
|
|
/* 0x/0X (hexadecimal) */
|
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return (16);
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} else {
|
|
/* Not a meaningful character */
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return (-1);
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}
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}
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|
|
|
|
function validateJsonObjectJS(schema, input)
|
|
{
|
|
var report = mod_jsonschema.validate(input, schema);
|
|
|
|
if (report.errors.length === 0)
|
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return (null);
|
|
|
|
/* Currently, we only do anything useful with the first error. */
|
|
var error = report.errors[0];
|
|
|
|
/* The failed property is given by a URI with an irrelevant prefix. */
|
|
var propname = error['property'];
|
|
var reason = error['message'].toLowerCase();
|
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var i, j;
|
|
|
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/*
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|
* There's at least one case where the property error message is
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* confusing at best. We work around this here.
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|
*/
|
|
if ((i = reason.indexOf('the property ')) != -1 &&
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(j = reason.indexOf(' is not defined in the schema and the ' +
|
|
'schema does not allow additional properties')) != -1) {
|
|
i += 'the property '.length;
|
|
if (propname === '')
|
|
propname = reason.substr(i, j - i);
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else
|
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propname = propname + '.' + reason.substr(i, j - i);
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|
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reason = 'unsupported property';
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|
}
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|
|
var rv = new mod_verror.VError('property "%s": %s', propname, reason);
|
|
rv.jsv_details = error;
|
|
return (rv);
|
|
}
|
|
|
|
function randElt(arr)
|
|
{
|
|
mod_assert.ok(Array.isArray(arr) && arr.length > 0,
|
|
'randElt argument must be a non-empty array');
|
|
|
|
return (arr[Math.floor(Math.random() * arr.length)]);
|
|
}
|
|
|
|
function assertHrtime(a)
|
|
{
|
|
mod_assert.ok(a[0] >= 0 && a[1] >= 0,
|
|
'negative numbers not allowed in hrtimes');
|
|
mod_assert.ok(a[1] < 1e9, 'nanoseconds column overflow');
|
|
}
|
|
|
|
/*
|
|
* Compute the time elapsed between hrtime readings A and B, where A is later
|
|
* than B. hrtime readings come from Node's process.hrtime(). There is no
|
|
* defined way to represent negative deltas, so it's illegal to diff B from A
|
|
* where the time denoted by B is later than the time denoted by A. If this
|
|
* becomes valuable, we can define a representation and extend the
|
|
* implementation to support it.
|
|
*/
|
|
function hrtimeDiff(a, b)
|
|
{
|
|
assertHrtime(a);
|
|
assertHrtime(b);
|
|
mod_assert.ok(a[0] > b[0] || (a[0] == b[0] && a[1] >= b[1]),
|
|
'negative differences not allowed');
|
|
|
|
var rv = [ a[0] - b[0], 0 ];
|
|
|
|
if (a[1] >= b[1]) {
|
|
rv[1] = a[1] - b[1];
|
|
} else {
|
|
rv[0]--;
|
|
rv[1] = 1e9 - (b[1] - a[1]);
|
|
}
|
|
|
|
return (rv);
|
|
}
|
|
|
|
/*
|
|
* Convert a hrtime reading from the array format returned by Node's
|
|
* process.hrtime() into a scalar number of nanoseconds.
|
|
*/
|
|
function hrtimeNanosec(a)
|
|
{
|
|
assertHrtime(a);
|
|
|
|
return (Math.floor(a[0] * 1e9 + a[1]));
|
|
}
|
|
|
|
/*
|
|
* Convert a hrtime reading from the array format returned by Node's
|
|
* process.hrtime() into a scalar number of microseconds.
|
|
*/
|
|
function hrtimeMicrosec(a)
|
|
{
|
|
assertHrtime(a);
|
|
|
|
return (Math.floor(a[0] * 1e6 + a[1] / 1e3));
|
|
}
|
|
|
|
/*
|
|
* Convert a hrtime reading from the array format returned by Node's
|
|
* process.hrtime() into a scalar number of milliseconds.
|
|
*/
|
|
function hrtimeMillisec(a)
|
|
{
|
|
assertHrtime(a);
|
|
|
|
return (Math.floor(a[0] * 1e3 + a[1] / 1e6));
|
|
}
|
|
|
|
/*
|
|
* Add two hrtime readings A and B, overwriting A with the result of the
|
|
* addition. This function is useful for accumulating several hrtime intervals
|
|
* into a counter. Returns A.
|
|
*/
|
|
function hrtimeAccum(a, b)
|
|
{
|
|
assertHrtime(a);
|
|
assertHrtime(b);
|
|
|
|
/*
|
|
* Accumulate the nanosecond component.
|
|
*/
|
|
a[1] += b[1];
|
|
if (a[1] >= 1e9) {
|
|
/*
|
|
* The nanosecond component overflowed, so carry to the seconds
|
|
* field.
|
|
*/
|
|
a[0]++;
|
|
a[1] -= 1e9;
|
|
}
|
|
|
|
/*
|
|
* Accumulate the seconds component.
|
|
*/
|
|
a[0] += b[0];
|
|
|
|
return (a);
|
|
}
|
|
|
|
/*
|
|
* Add two hrtime readings A and B, returning the result as a new hrtime array.
|
|
* Does not modify either input argument.
|
|
*/
|
|
function hrtimeAdd(a, b)
|
|
{
|
|
assertHrtime(a);
|
|
|
|
var rv = [ a[0], a[1] ];
|
|
|
|
return (hrtimeAccum(rv, b));
|
|
}
|
|
|
|
|
|
/*
|
|
* Check an object for unexpected properties. Accepts the object to check, and
|
|
* an array of allowed property names (strings). Returns an array of key names
|
|
* that were found on the object, but did not appear in the list of allowed
|
|
* properties. If no properties were found, the returned array will be of
|
|
* zero length.
|
|
*/
|
|
function extraProperties(obj, allowed)
|
|
{
|
|
mod_assert.ok(typeof (obj) === 'object' && obj !== null,
|
|
'obj argument must be a non-null object');
|
|
mod_assert.ok(Array.isArray(allowed),
|
|
'allowed argument must be an array of strings');
|
|
for (var i = 0; i < allowed.length; i++) {
|
|
mod_assert.ok(typeof (allowed[i]) === 'string',
|
|
'allowed argument must be an array of strings');
|
|
}
|
|
|
|
return (Object.keys(obj).filter(function (key) {
|
|
return (allowed.indexOf(key) === -1);
|
|
}));
|
|
}
|
|
|
|
/*
|
|
* Given three sets of properties "provided" (may be undefined), "overrides"
|
|
* (required), and "defaults" (may be undefined), construct an object containing
|
|
* the union of these sets with "overrides" overriding "provided", and
|
|
* "provided" overriding "defaults". None of the input objects are modified.
|
|
*/
|
|
function mergeObjects(provided, overrides, defaults)
|
|
{
|
|
var rv, k;
|
|
|
|
rv = {};
|
|
if (defaults) {
|
|
for (k in defaults)
|
|
rv[k] = defaults[k];
|
|
}
|
|
|
|
if (provided) {
|
|
for (k in provided)
|
|
rv[k] = provided[k];
|
|
}
|
|
|
|
if (overrides) {
|
|
for (k in overrides)
|
|
rv[k] = overrides[k];
|
|
}
|
|
|
|
return (rv);
|
|
}
|