Spaces:
Sleeping
Sleeping
File size: 5,737 Bytes
78c921d |
1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60 61 62 63 64 65 66 67 68 69 70 71 72 73 74 75 76 77 78 79 80 81 82 83 84 85 86 87 88 89 90 91 92 93 94 95 96 97 98 99 100 101 102 103 104 105 106 107 108 109 110 111 112 113 114 115 116 117 118 119 120 121 122 123 124 125 126 127 128 129 130 131 132 133 134 135 136 137 138 139 140 141 142 143 144 145 146 147 148 149 150 151 152 153 154 155 156 157 158 159 160 |
// Licensed to the Apache Software Foundation (ASF) under one
// or more contributor license agreements. See the NOTICE file
// distributed with this work for additional information
// regarding copyright ownership. The ASF licenses this file
// to you under the Apache License, Version 2.0 (the
// "License"); you may not use this file except in compliance
// with the License. You may obtain a copy of the License at
//
// http://www.apache.org/licenses/LICENSE-2.0
//
// Unless required by applicable law or agreed to in writing,
// software distributed under the License is distributed on an
// "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY
// KIND, either express or implied. See the License for the
// specific language governing permissions and limitations
// under the License.
import { Data } from '../data.js';
import { Field } from '../schema.js';
import { Struct, TypeMap } from '../type.js';
import { valueToString } from '../util/pretty.js';
import { instance as getVisitor } from '../visitor/get.js';
import { instance as setVisitor } from '../visitor/set.js';
/** @ignore */ const kParent = Symbol.for('parent');
/** @ignore */ const kRowIndex = Symbol.for('rowIndex');
export type StructRowProxy<T extends TypeMap = any> = StructRow<T> & {
[P in keyof T]: T[P]['TValue'];
} & {
[key: symbol]: any;
};
export class StructRow<T extends TypeMap = any> {
declare private [kRowIndex]: number;
declare private [kParent]: Data<Struct<T>>;
constructor(parent: Data<Struct<T>>, rowIndex: number) {
this[kParent] = parent;
this[kRowIndex] = rowIndex;
return new Proxy(this, new StructRowProxyHandler());
}
public toArray() { return Object.values(this.toJSON()); }
public toJSON() {
const i = this[kRowIndex];
const parent = this[kParent];
const keys = parent.type.children;
const json = {} as { [P in string & keyof T]: T[P]['TValue'] };
for (let j = -1, n = keys.length; ++j < n;) {
json[keys[j].name as string & keyof T] = getVisitor.visit(parent.children[j], i);
}
return json;
}
public toString() {
return `{${[...this].map(([key, val]) =>
`${valueToString(key)}: ${valueToString(val)}`
).join(', ')
}}`;
}
public [Symbol.for('nodejs.util.inspect.custom')]() {
return this.toString();
}
[Symbol.iterator](): IterableIterator<[
keyof T, { [P in keyof T]: T[P]['TValue'] | null }[keyof T]
]> {
return new StructRowIterator(this[kParent], this[kRowIndex]);
}
}
class StructRowIterator<T extends TypeMap = any>
implements IterableIterator<[
keyof T, { [P in keyof T]: T[P]['TValue'] | null }[keyof T]
]> {
declare private rowIndex: number;
declare private childIndex: number;
declare private numChildren: number;
declare private children: Data<any>[];
declare private childFields: Field<T[keyof T]>[];
constructor(data: Data<Struct<T>>, rowIndex: number) {
this.childIndex = 0;
this.children = data.children;
this.rowIndex = rowIndex;
this.childFields = data.type.children;
this.numChildren = this.childFields.length;
}
[Symbol.iterator]() { return this; }
next() {
const i = this.childIndex;
if (i < this.numChildren) {
this.childIndex = i + 1;
return {
done: false,
value: [
this.childFields[i].name,
getVisitor.visit(this.children[i], this.rowIndex)
]
} as IteratorYieldResult<[any, any]>;
}
return { done: true, value: null } as IteratorReturnResult<null>;
}
}
Object.defineProperties(StructRow.prototype, {
[Symbol.toStringTag]: { enumerable: false, configurable: false, value: 'Row' },
[kParent]: { writable: true, enumerable: false, configurable: false, value: null },
[kRowIndex]: { writable: true, enumerable: false, configurable: false, value: -1 },
});
class StructRowProxyHandler<T extends TypeMap = any> implements ProxyHandler<StructRow<T>> {
isExtensible() { return false; }
deleteProperty() { return false; }
preventExtensions() { return true; }
ownKeys(row: StructRow<T>) {
return row[kParent].type.children.map((f) => f.name);
}
has(row: StructRow<T>, key: string) {
return row[kParent].type.children.findIndex((f) => f.name === key) !== -1;
}
getOwnPropertyDescriptor(row: StructRow<T>, key: string) {
if (row[kParent].type.children.findIndex((f) => f.name === key) !== -1) {
return { writable: true, enumerable: true, configurable: true };
}
return;
}
get(row: StructRow<T>, key: string) {
// Look up key in row first
if (Reflect.has(row, key)) {
return (row as any)[key];
}
const idx = row[kParent].type.children.findIndex((f) => f.name === key);
if (idx !== -1) {
const val = getVisitor.visit(row[kParent].children[idx], row[kRowIndex]);
// Cache key/val lookups
Reflect.set(row, key, val);
return val;
}
}
set(row: StructRow<T>, key: string, val: any) {
const idx = row[kParent].type.children.findIndex((f) => f.name === key);
if (idx !== -1) {
setVisitor.visit(row[kParent].children[idx], row[kRowIndex], val);
// Cache key/val lookups
return Reflect.set(row, key, val);
} else if (Reflect.has(row, key) || typeof key === 'symbol') {
return Reflect.set(row, key, val);
}
return false;
}
}
|