Add ObjectPropertyAccessor
This commit is contained in:
toasted-nutbread
parent
1cacbb6202
commit
6865fc0b52
244
ext/mixed/js/object-property-accessor.js
Normal file
244
ext/mixed/js/object-property-accessor.js
Normal file
|
|
@ -0,0 +1,244 @@
|
|||
/*
|
||||
* Copyright (C) 2016-2020 Alex Yatskov <alex@foosoft.net>
|
||||
* Author: Alex Yatskov <alex@foosoft.net>
|
||||
*
|
||||
* This program is free software: you can redistribute it and/or modify
|
||||
* it under the terms of the GNU General Public License as published by
|
||||
* the Free Software Foundation, either version 3 of the License, or
|
||||
* (at your option) any later version.
|
||||
*
|
||||
* This program is distributed in the hope that it will be useful,
|
||||
* but WITHOUT ANY WARRANTY; without even the implied warranty of
|
||||
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
|
||||
* GNU General Public License for more details.
|
||||
*
|
||||
* You should have received a copy of the GNU General Public License
|
||||
* along with this program. If not, see <https://www.gnu.org/licenses/>.
|
||||
*/
|
||||
|
||||
/**
|
||||
* Class used to get and set generic properties of an object by using path strings.
|
||||
*/
|
||||
class ObjectPropertyAccessor {
|
||||
constructor(target, setter=null) {
|
||||
this._target = target;
|
||||
this._setter = (typeof setter === 'function' ? setter : null);
|
||||
}
|
||||
|
||||
getProperty(pathArray, pathLength) {
|
||||
let target = this._target;
|
||||
const ii = typeof pathLength === 'number' ? Math.min(pathArray.length, pathLength) : pathArray.length;
|
||||
for (let i = 0; i < ii; ++i) {
|
||||
const key = pathArray[i];
|
||||
if (!ObjectPropertyAccessor.hasProperty(target, key)) {
|
||||
throw new Error(`Invalid path: ${this.getPathString(pathArray.slice(0, i + 1))}`);
|
||||
}
|
||||
target = target[key];
|
||||
}
|
||||
return target;
|
||||
}
|
||||
|
||||
setProperty(pathArray, value) {
|
||||
if (pathArray.length === 0) {
|
||||
throw new Error('Invalid path');
|
||||
}
|
||||
|
||||
const target = this.getProperty(pathArray, pathArray.length - 1);
|
||||
const key = pathArray[pathArray.length - 1];
|
||||
if (!ObjectPropertyAccessor.isValidPropertyType(target, key)) {
|
||||
throw new Error(`Invalid path: ${this.getPathString(pathArray)}`);
|
||||
}
|
||||
|
||||
if (this._setter !== null) {
|
||||
this._setter(target, key, value, pathArray);
|
||||
} else {
|
||||
target[key] = value;
|
||||
}
|
||||
}
|
||||
|
||||
static getPathString(pathArray) {
|
||||
const regexShort = /^[a-zA-Z_][a-zA-Z0-9_]*$/;
|
||||
let pathString = '';
|
||||
let first = true;
|
||||
for (let part of pathArray) {
|
||||
switch (typeof part) {
|
||||
case 'number':
|
||||
if (Math.floor(part) !== part || part < 0) {
|
||||
throw new Error('Invalid index');
|
||||
}
|
||||
part = `[${part}]`;
|
||||
break;
|
||||
case 'string':
|
||||
if (!regexShort.test(part)) {
|
||||
const escapedPart = part.replace(/["\\]/g, '\\$&');
|
||||
part = `["${escapedPart}"]`;
|
||||
} else {
|
||||
if (!first) {
|
||||
part = `.${part}`;
|
||||
}
|
||||
}
|
||||
break;
|
||||
default:
|
||||
throw new Error(`Invalid type: ${typeof part}`);
|
||||
}
|
||||
pathString += part;
|
||||
first = false;
|
||||
}
|
||||
return pathString;
|
||||
}
|
||||
|
||||
static getPathArray(pathString) {
|
||||
const pathArray = [];
|
||||
let state = 0;
|
||||
let quote = 0;
|
||||
let value = '';
|
||||
let escaped = false;
|
||||
for (const c of pathString) {
|
||||
const v = c.codePointAt(0);
|
||||
switch (state) {
|
||||
case 0: // Empty
|
||||
case 1: // Expecting identifier start
|
||||
if (v === 0x5b) { // '['
|
||||
if (state === 1) {
|
||||
throw new Error(`Unexpected character: ${c}`);
|
||||
}
|
||||
state = 3;
|
||||
} else if (
|
||||
(v >= 0x41 && v <= 0x5a) || // ['A', 'Z']
|
||||
(v >= 0x61 && v <= 0x7a) || // ['a', 'z']
|
||||
v === 0x5f // '_'
|
||||
) {
|
||||
state = 2;
|
||||
value += c;
|
||||
} else {
|
||||
throw new Error(`Unexpected character: ${c}`);
|
||||
}
|
||||
break;
|
||||
case 2: // Identifier
|
||||
if (
|
||||
(v >= 0x41 && v <= 0x5a) || // ['A', 'Z']
|
||||
(v >= 0x61 && v <= 0x7a) || // ['a', 'z']
|
||||
(v >= 0x30 && v <= 0x39) || // ['0', '9']
|
||||
v === 0x5f // '_'
|
||||
) {
|
||||
value += c;
|
||||
} else if (v === 0x5b) { // '['
|
||||
pathArray.push(value);
|
||||
value = '';
|
||||
state = 3;
|
||||
} else if (v === 0x2e) { // '.'
|
||||
pathArray.push(value);
|
||||
value = '';
|
||||
state = 1;
|
||||
} else {
|
||||
throw new Error(`Unexpected character: ${c}`);
|
||||
}
|
||||
break;
|
||||
case 3: // Open bracket
|
||||
if (v === 0x22 || v === 0x27) { // '"' or '\''
|
||||
quote = v;
|
||||
state = 4;
|
||||
} else if (v >= 0x30 && v <= 0x39) { // ['0', '9']
|
||||
state = 5;
|
||||
value += c;
|
||||
} else {
|
||||
throw new Error(`Unexpected character: ${c}`);
|
||||
}
|
||||
break;
|
||||
case 4: // Quoted string
|
||||
if (escaped) {
|
||||
value += c;
|
||||
escaped = false;
|
||||
} else if (v === 0x5c) { // '\\'
|
||||
escaped = true;
|
||||
} else if (v !== quote) {
|
||||
value += c;
|
||||
} else {
|
||||
state = 6;
|
||||
}
|
||||
break;
|
||||
case 5: // Number
|
||||
if (v >= 0x30 && v <= 0x39) { // ['0', '9']
|
||||
value += c;
|
||||
} else if (v === 0x5d) { // ']'
|
||||
pathArray.push(Number.parseInt(value, 10));
|
||||
value = '';
|
||||
state = 7;
|
||||
} else {
|
||||
throw new Error(`Unexpected character: ${c}`);
|
||||
}
|
||||
break;
|
||||
case 6: // Expecting closing bracket after quoted string
|
||||
if (v === 0x5d) { // ']'
|
||||
pathArray.push(value);
|
||||
value = '';
|
||||
state = 7;
|
||||
} else {
|
||||
throw new Error(`Unexpected character: ${c}`);
|
||||
}
|
||||
break;
|
||||
case 7: // Expecting . or [
|
||||
if (v === 0x5b) { // '['
|
||||
state = 3;
|
||||
} else if (v === 0x2e) { // '.'
|
||||
state = 1;
|
||||
} else {
|
||||
throw new Error(`Unexpected character: ${c}`);
|
||||
}
|
||||
break;
|
||||
}
|
||||
}
|
||||
switch (state) {
|
||||
case 0:
|
||||
case 7:
|
||||
break;
|
||||
case 2:
|
||||
pathArray.push(value);
|
||||
value = '';
|
||||
break;
|
||||
default:
|
||||
throw new Error('Path not terminated correctly');
|
||||
}
|
||||
return pathArray;
|
||||
}
|
||||
|
||||
static hasProperty(object, property) {
|
||||
switch (typeof property) {
|
||||
case 'string':
|
||||
return (
|
||||
typeof object === 'object' &&
|
||||
object !== null &&
|
||||
!Array.isArray(object) &&
|
||||
Object.prototype.hasOwnProperty.call(object, property)
|
||||
);
|
||||
case 'number':
|
||||
return (
|
||||
Array.isArray(object) &&
|
||||
property >= 0 &&
|
||||
property < object.length &&
|
||||
property === Math.floor(property)
|
||||
);
|
||||
default:
|
||||
return false;
|
||||
}
|
||||
}
|
||||
|
||||
static isValidPropertyType(object, property) {
|
||||
switch (typeof property) {
|
||||
case 'string':
|
||||
return (
|
||||
typeof object === 'object' &&
|
||||
object !== null &&
|
||||
!Array.isArray(object)
|
||||
);
|
||||
case 'number':
|
||||
return (
|
||||
Array.isArray(object) &&
|
||||
property >= 0 &&
|
||||
property === Math.floor(property)
|
||||
);
|
||||
default:
|
||||
return false;
|
||||
}
|
||||
}
|
||||
}
|
||||
Loading…
Reference in New Issue
Block a user