/**
* Copyright 2017 Google Inc.
*
* Licensed 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 { Index } from './Index';
import { Node, NamedNode } from '../Node';
import { nameCompare, MAX_NAME } from '../../util/util';
import { assert, assertionError } from '@firebase/util';
import { ChildrenNode } from '../ChildrenNode';
let __EMPTY_NODE: ChildrenNode;
export class KeyIndex extends Index {
static get __EMPTY_NODE() {
return __EMPTY_NODE;
}
static set __EMPTY_NODE(val) {
__EMPTY_NODE = val;
}
/**
* @inheritDoc
*/
compare(a: NamedNode, b: NamedNode): number {
return nameCompare(a.name, b.name);
}
/**
* @inheritDoc
*/
isDefinedOn(node: Node): boolean {
// We could probably return true here (since every node has a key), but it's never called
// so just leaving unimplemented for now.
throw assertionError('KeyIndex.isDefinedOn not expected to be called.');
}
/**
* @inheritDoc
*/
indexedValueChanged(oldNode: Node, newNode: Node): boolean {
return false; // The key for a node never changes.
}
/**
* @inheritDoc
*/
minPost() {
return (NamedNode as any).MIN;
}
/**
* @inheritDoc
*/
maxPost(): NamedNode {
// TODO: This should really be created once and cached in a static property, but
// NamedNode isn't defined yet, so I can't use it in a static. Bleh.
return new NamedNode(MAX_NAME, __EMPTY_NODE);
}
/**
* @param {*} indexValue
* @param {string} name
* @return {!NamedNode}
*/
makePost(indexValue: string, name: string): NamedNode {
assert(
typeof indexValue === 'string',
'KeyIndex indexValue must always be a string.'
);
// We just use empty node, but it'll never be compared, since our comparator only looks at name.
return new NamedNode(indexValue, __EMPTY_NODE);
}
/**
* @return {!string} String representation for inclusion in a query spec
*/
toString(): string {
return '.key';
}
}
export const KEY_INDEX = new KeyIndex();
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