127 lines
3.6 KiB
TypeScript

/**
* @license
* Copyright Google Inc. All Rights Reserved.
*
* Use of this source code is governed by an MIT-style license that can be
* found in the LICENSE file at https://angular.io/license
*/
import {ConstantPool} from '../../constant_pool';
import * as o from '../../output/output_ast';
import * as t from '../r3_ast';
import {R3QueryMetadata} from './api';
/** Name of the temporary to use during data binding */
export const TEMPORARY_NAME = '_t';
/** Name of the context parameter passed into a template function */
export const CONTEXT_NAME = 'ctx';
/** Name of the RenderFlag passed into a template function */
export const RENDER_FLAGS = 'rf';
/** The prefix reference variables */
export const REFERENCE_PREFIX = '_r';
/** The name of the implicit context reference */
export const IMPLICIT_REFERENCE = '$implicit';
/** Name of the i18n attributes **/
export const I18N_ATTR = 'i18n';
export const I18N_ATTR_PREFIX = 'i18n-';
/** I18n separators for metadata **/
export const MEANING_SEPARATOR = '|';
export const ID_SEPARATOR = '@@';
/** Non bindable attribute name **/
export const NON_BINDABLE_ATTR = 'ngNonBindable';
/**
* Creates an allocator for a temporary variable.
*
* A variable declaration is added to the statements the first time the allocator is invoked.
*/
export function temporaryAllocator(statements: o.Statement[], name: string): () => o.ReadVarExpr {
let temp: o.ReadVarExpr|null = null;
return () => {
if (!temp) {
statements.push(new o.DeclareVarStmt(TEMPORARY_NAME, undefined, o.DYNAMIC_TYPE));
temp = o.variable(name);
}
return temp;
};
}
export function unsupported(feature: string): never {
if (this) {
throw new Error(`Builder ${this.constructor.name} doesn't support ${feature} yet`);
}
throw new Error(`Feature ${feature} is not supported yet`);
}
export function invalid<T>(arg: o.Expression | o.Statement | t.Node): never {
throw new Error(
`Invalid state: Visitor ${this.constructor.name} doesn't handle ${o.constructor.name}`);
}
export function isI18NAttribute(name: string): boolean {
return name === I18N_ATTR || name.startsWith(I18N_ATTR_PREFIX);
}
export function asLiteral(value: any): o.Expression {
if (Array.isArray(value)) {
return o.literalArr(value.map(asLiteral));
}
return o.literal(value, o.INFERRED_TYPE);
}
export function conditionallyCreateMapObjectLiteral(keys: {[key: string]: string}): o.Expression|
null {
if (Object.getOwnPropertyNames(keys).length > 0) {
return mapToExpression(keys);
}
return null;
}
export function mapToExpression(map: {[key: string]: any}, quoted = false): o.Expression {
return o.literalMap(
Object.getOwnPropertyNames(map).map(key => ({key, quoted, value: asLiteral(map[key])})));
}
/**
* Remove trailing null nodes as they are implied.
*/
export function trimTrailingNulls(parameters: o.Expression[]): o.Expression[] {
while (o.isNull(parameters[parameters.length - 1])) {
parameters.pop();
}
return parameters;
}
export function getQueryPredicate(
query: R3QueryMetadata, constantPool: ConstantPool): o.Expression {
if (Array.isArray(query.predicate)) {
return constantPool.getConstLiteral(
o.literalArr(query.predicate.map(selector => o.literal(selector) as o.Expression)));
} else {
return query.predicate;
}
}
export function noop() {}
export class DefinitionMap {
values: {key: string, quoted: boolean, value: o.Expression}[] = [];
set(key: string, value: o.Expression|null): void {
if (value) {
this.values.push({key, value, quoted: false});
}
}
toLiteralMap(): o.LiteralMapExpr { return o.literalMap(this.values); }
}