angular-cn/packages/compiler/src/render3/view/compiler.ts

/**
 * @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 {StaticSymbol} from '../../aot/static_symbol';
import {CompileDiDependencyMetadata, CompileDirectiveMetadata, CompileDirectiveSummary, CompilePipeMetadata, CompileQueryMetadata, CompileTokenMetadata, CompileTypeMetadata, flatten, identifierName, sanitizeIdentifier, tokenReference} from '../../compile_metadata';
import {CompileReflector} from '../../compile_reflector';
import {BindingForm, BuiltinFunctionCall, LocalResolver, convertActionBinding, convertPropertyBinding} from '../../compiler_util/expression_converter';
import {ConstantPool, DefinitionKind} from '../../constant_pool';
import * as core from '../../core';
import {AST, AstMemoryEfficientTransformer, BindingPipe, BoundElementBindingType, FunctionCall, ImplicitReceiver, LiteralArray, LiteralMap, LiteralPrimitive, PropertyRead} from '../../expression_parser/ast';
import {Identifiers} from '../../identifiers';
import {LifecycleHooks} from '../../lifecycle_reflector';
import * as o from '../../output/output_ast';
import {ParseSourceSpan, typeSourceSpan} from '../../parse_util';
import {CssSelector, SelectorMatcher} from '../../selector';
import {BindingParser} from '../../template_parser/binding_parser';
import {OutputContext, error} from '../../util';

import * as t from './../r3_ast';
import {R3DependencyMetadata, R3ResolvedDependencyType, compileFactoryFunction, dependenciesFromGlobalMetadata} from './../r3_factory';
import {Identifiers as R3} from './../r3_identifiers';
import {R3ComponentDef, R3ComponentMetadata, R3DirectiveDef, R3DirectiveMetadata, R3QueryMetadata} from './api';
import {BindingScope, TemplateDefinitionBuilder} from './template';
import {CONTEXT_NAME, DefinitionMap, ID_SEPARATOR, MEANING_SEPARATOR, TEMPORARY_NAME, asLiteral, conditionallyCreateMapObjectLiteral, getQueryPredicate, temporaryAllocator, unsupported} from './util';

function baseDirectiveFields(
    meta: R3DirectiveMetadata, constantPool: ConstantPool,
    bindingParser: BindingParser): DefinitionMap {
  const definitionMap = new DefinitionMap();

  // e.g. `type: MyDirective`
  definitionMap.set('type', meta.type);

  // e.g. `selectors: [['', 'someDir', '']]`
  definitionMap.set('selectors', createDirectiveSelector(meta.selector !));

  const queryDefinitions = createQueryDefinitions(meta.queries, constantPool);

  // e.g. `factory: () => new MyApp(injectElementRef())`
  definitionMap.set('factory', compileFactoryFunction({
                      name: meta.name,
                      fnOrClass: meta.type,
                      deps: meta.deps,
                      useNew: true,
                      injectFn: R3.directiveInject,
                      useOptionalParam: false,
                      extraResults: queryDefinitions,
                    }));

  // e.g. `hostBindings: (dirIndex, elIndex) => { ... }
  definitionMap.set('hostBindings', createHostBindingsFunction(meta, bindingParser));

  // e.g. `attributes: ['role', 'listbox']`
  definitionMap.set('attributes', createHostAttributesArray(meta));

  // e.g 'inputs: {a: 'a'}`
  definitionMap.set('inputs', conditionallyCreateMapObjectLiteral(meta.inputs));

  // e.g 'outputs: {a: 'a'}`
  definitionMap.set('outputs', conditionallyCreateMapObjectLiteral(meta.outputs));

  return definitionMap;
}

/**
 * Compile a directive for the render3 runtime as defined by the `R3DirectiveMetadata`.
 */
export function compileDirective(
    meta: R3DirectiveMetadata, constantPool: ConstantPool,
    bindingParser: BindingParser): R3DirectiveDef {
  const definitionMap = baseDirectiveFields(meta, constantPool, bindingParser);
  const expression = o.importExpr(R3.defineDirective).callFn([definitionMap.toLiteralMap()]);
  const type =
      new o.ExpressionType(o.importExpr(R3.DirectiveDef, [new o.ExpressionType(meta.type)]));
  return {expression, type};
}

/**
 * Compile a component for the render3 runtime as defined by the `R3ComponentMetadata`.
 */
export function compileComponent(
    meta: R3ComponentMetadata, constantPool: ConstantPool,
    bindingParser: BindingParser): R3ComponentDef {
  const definitionMap = baseDirectiveFields(meta, constantPool, bindingParser);

  const selector = meta.selector && CssSelector.parse(meta.selector);
  const firstSelector = selector && selector[0];

  // e.g. `attr: ["class", ".my.app"]`
  // This is optional an only included if the first selector of a component specifies attributes.
  if (firstSelector) {
    const selectorAttributes = firstSelector.getAttrs();
    if (selectorAttributes.length) {
      definitionMap.set(
          'attrs', constantPool.getConstLiteral(
                       o.literalArr(selectorAttributes.map(
                           value => value != null ? o.literal(value) : o.literal(undefined))),
                       /* forceShared */ true));
    }
  }

  // Generate the CSS matcher that recognize directive
  let directiveMatcher: SelectorMatcher|null = null;

  if (meta.directives.size) {
    const matcher = new SelectorMatcher();
    meta.directives.forEach((expression, selector: string) => {
      matcher.addSelectables(CssSelector.parse(selector), expression);
    });
    directiveMatcher = matcher;
  }

  // e.g. `template: function MyComponent_Template(_ctx, _cm) {...}`
  const templateTypeName = meta.name;
  const templateName = templateTypeName ? `${templateTypeName}_Template` : null;

  const directivesUsed = new Set<o.Expression>();
  const pipesUsed = new Set<o.Expression>();

  const template = meta.template;
  const templateFunctionExpression =
      new TemplateDefinitionBuilder(
          constantPool, CONTEXT_NAME, BindingScope.ROOT_SCOPE, 0, templateTypeName, templateName,
          meta.viewQueries, directiveMatcher, directivesUsed, meta.pipes, pipesUsed)
          .buildTemplateFunction(
              template.nodes, [], template.hasNgContent, template.ngContentSelectors);

  definitionMap.set('template', templateFunctionExpression);

  // e.g. `directives: [MyDirective]`
  if (directivesUsed.size) {
    definitionMap.set('directives', o.literalArr(Array.from(directivesUsed)));
  }

  // e.g. `pipes: [MyPipe]`
  if (pipesUsed.size) {
    definitionMap.set('pipes', o.literalArr(Array.from(pipesUsed)));
  }

  // e.g. `features: [NgOnChangesFeature(MyComponent)]`
  const features: o.Expression[] = [];
  if (meta.lifecycle.usesOnChanges) {
    features.push(o.importExpr(R3.NgOnChangesFeature, null, null).callFn([meta.type]));
  }
  if (features.length) {
    definitionMap.set('features', o.literalArr(features));
  }

  const expression = o.importExpr(R3.defineComponent).callFn([definitionMap.toLiteralMap()]);
  const type =
      new o.ExpressionType(o.importExpr(R3.ComponentDef, [new o.ExpressionType(meta.type)]));

  return {expression, type};
}

/**
 * A wrapper around `compileDirective` which depends on render2 global analysis data as its input
 * instead of the `R3DirectiveMetadata`.
 *
 * `R3DirectiveMetadata` is computed from `CompileDirectiveMetadata` and other statically reflected
 * information.
 */
export function compileDirectiveFromRender2(
    outputCtx: OutputContext, directive: CompileDirectiveMetadata, reflector: CompileReflector,
    bindingParser: BindingParser) {
  const name = identifierName(directive.type) !;
  name || error(`Cannot resolver the name of ${directive.type}`);

  const definitionField = outputCtx.constantPool.propertyNameOf(DefinitionKind.Directive);

  const meta = directiveMetadataFromGlobalMetadata(directive, outputCtx, reflector);
  const res = compileDirective(meta, outputCtx.constantPool, bindingParser);

  // Create the partial class to be merged with the actual class.
  outputCtx.statements.push(new o.ClassStmt(
      name, null,
      [new o.ClassField(definitionField, o.INFERRED_TYPE, [o.StmtModifier.Static], res.expression)],
      [], new o.ClassMethod(null, [], []), []));
}

/**
 * A wrapper around `compileComponent` which depends on render2 global analysis data as its input
 * instead of the `R3DirectiveMetadata`.
 *
 * `R3ComponentMetadata` is computed from `CompileDirectiveMetadata` and other statically reflected
 * information.
 */
export function compileComponentFromRender2(
    outputCtx: OutputContext, component: CompileDirectiveMetadata, nodes: t.Node[],
    hasNgContent: boolean, ngContentSelectors: string[], reflector: CompileReflector,
    bindingParser: BindingParser, directiveTypeBySel: Map<string, any>,
    pipeTypeByName: Map<string, any>) {
  const name = identifierName(component.type) !;
  name || error(`Cannot resolver the name of ${component.type}`);

  const definitionField = outputCtx.constantPool.propertyNameOf(DefinitionKind.Component);

  const summary = component.toSummary();

  // Compute the R3ComponentMetadata from the CompileDirectiveMetadata
  const meta: R3ComponentMetadata = {
    ...directiveMetadataFromGlobalMetadata(component, outputCtx, reflector),
    selector: component.selector,
    template: {
        nodes, hasNgContent, ngContentSelectors,
    },
    lifecycle: {
      usesOnChanges:
          component.type.lifecycleHooks.some(lifecycle => lifecycle == LifecycleHooks.OnChanges),
    },
    directives: typeMapToExpressionMap(directiveTypeBySel, outputCtx),
    pipes: typeMapToExpressionMap(pipeTypeByName, outputCtx),
    viewQueries: queriesFromGlobalMetadata(component.viewQueries, outputCtx),
  };
  const res = compileComponent(meta, outputCtx.constantPool, bindingParser);

  // Create the partial class to be merged with the actual class.
  outputCtx.statements.push(new o.ClassStmt(
      name, null,
      [new o.ClassField(definitionField, o.INFERRED_TYPE, [o.StmtModifier.Static], res.expression)],
      [], new o.ClassMethod(null, [], []), []));
}

/**
 * Compute `R3DirectiveMetadata` given `CompileDirectiveMetadata` and a `CompileReflector`.
 */
function directiveMetadataFromGlobalMetadata(
    directive: CompileDirectiveMetadata, outputCtx: OutputContext,
    reflector: CompileReflector): R3DirectiveMetadata {
  const summary = directive.toSummary();
  const name = identifierName(directive.type) !;
  name || error(`Cannot resolver the name of ${directive.type}`);

  return {
    name,
    type: outputCtx.importExpr(directive.type.reference),
    typeSourceSpan:
        typeSourceSpan(directive.isComponent ? 'Component' : 'Directive', directive.type),
    selector: directive.selector,
    deps: dependenciesFromGlobalMetadata(directive.type, outputCtx, reflector),
    queries: queriesFromGlobalMetadata(directive.queries, outputCtx),
    host: {
      attributes: directive.hostAttributes,
      listeners: summary.hostListeners,
      properties: summary.hostProperties,
    },
    inputs: directive.inputs,
    outputs: directive.outputs,
  };
}

/**
 * Convert `CompileQueryMetadata` into `R3QueryMetadata`.
 */
function queriesFromGlobalMetadata(
    queries: CompileQueryMetadata[], outputCtx: OutputContext): R3QueryMetadata[] {
  return queries.map(query => {
    let read: o.Expression|null = null;
    if (query.read && query.read.identifier) {
      read = outputCtx.importExpr(query.read.identifier.reference);
    }
    return {
      propertyName: query.propertyName,
      first: query.first,
      predicate: selectorsFromGlobalMetadata(query.selectors, outputCtx),
      descendants: query.descendants, read,
    };
  });
}

/**
 * Convert `CompileTokenMetadata` for query selectors into either an expression for a predicate
 * type, or a list of string predicates.
 */
function selectorsFromGlobalMetadata(
    selectors: CompileTokenMetadata[], outputCtx: OutputContext): o.Expression|string[] {
  if (selectors.length > 1 || (selectors.length == 1 && selectors[0].value)) {
    const selectorStrings = selectors.map(value => value.value as string);
    selectorStrings.some(value => !value) &&
        error('Found a type among the string selectors expected');
    return outputCtx.constantPool.getConstLiteral(
        o.literalArr(selectorStrings.map(value => o.literal(value))));
  }

  if (selectors.length == 1) {
    const first = selectors[0];
    if (first.identifier) {
      return outputCtx.importExpr(first.identifier.reference);
    }
  }

  error('Unexpected query form');
  return o.NULL_EXPR;
}

/**
 *
 * @param meta
 * @param constantPool
 */
function createQueryDefinitions(
    queries: R3QueryMetadata[], constantPool: ConstantPool): o.Expression[]|undefined {
  const queryDefinitions: o.Expression[] = [];
  for (let i = 0; i < queries.length; i++) {
    const query = queries[i];
    const predicate = getQueryPredicate(query, constantPool);

    // e.g. r3.Q(null, somePredicate, false) or r3.Q(null, ['div'], false)
    const parameters = [
      o.literal(null, o.INFERRED_TYPE),
      predicate,
      o.literal(query.descendants),
    ];

    if (query.read) {
      parameters.push(query.read);
    }

    queryDefinitions.push(o.importExpr(R3.query).callFn(parameters));
  }
  return queryDefinitions.length > 0 ? queryDefinitions : undefined;
}

// Turn a directive selector into an R3-compatible selector for directive def
function createDirectiveSelector(selector: string): o.Expression {
  return asLiteral(core.parseSelectorToR3Selector(selector));
}

function createHostAttributesArray(meta: R3DirectiveMetadata): o.Expression|null {
  const values: o.Expression[] = [];
  const attributes = meta.host.attributes;
  for (let key of Object.getOwnPropertyNames(attributes)) {
    const value = attributes[key];
    values.push(o.literal(key), o.literal(value));
  }
  if (values.length > 0) {
    return o.literalArr(values);
  }
  return null;
}

// Return a host binding function or null if one is not necessary.
function createHostBindingsFunction(
    meta: R3DirectiveMetadata, bindingParser: BindingParser): o.Expression|null {
  const statements: o.Statement[] = [];

  const temporary = temporaryAllocator(statements, TEMPORARY_NAME);

  const hostBindingSourceSpan = meta.typeSourceSpan;

  // Calculate the queries
  for (let index = 0; index < meta.queries.length; index++) {
    const query = meta.queries[index];

    // e.g. r3.qR(tmp = r3.ld(dirIndex)[1]) && (r3.ld(dirIndex)[0].someDir = tmp);
    const getDirectiveMemory = o.importExpr(R3.load).callFn([o.variable('dirIndex')]);
    // The query list is at the query index + 1 because the directive itself is in slot 0.
    const getQueryList = getDirectiveMemory.key(o.literal(index + 1));
    const assignToTemporary = temporary().set(getQueryList);
    const callQueryRefresh = o.importExpr(R3.queryRefresh).callFn([assignToTemporary]);
    const updateDirective = getDirectiveMemory.key(o.literal(0, o.INFERRED_TYPE))
                                .prop(query.propertyName)
                                .set(query.first ? temporary().prop('first') : temporary());
    const andExpression = callQueryRefresh.and(updateDirective);
    statements.push(andExpression.toStmt());
  }

  const directiveSummary = metadataAsSummary(meta);

  // Calculate the host property bindings
  const bindings = bindingParser.createBoundHostProperties(directiveSummary, hostBindingSourceSpan);
  const bindingContext = o.importExpr(R3.load).callFn([o.variable('dirIndex')]);
  if (bindings) {
    for (const binding of bindings) {
      const bindingExpr = convertPropertyBinding(
          null, bindingContext, binding.expression, 'b', BindingForm.TrySimple,
          () => error('Unexpected interpolation'));
      statements.push(...bindingExpr.stmts);
      statements.push(o.importExpr(R3.elementProperty)
                          .callFn([
                            o.variable('elIndex'),
                            o.literal(binding.name),
                            o.importExpr(R3.bind).callFn([bindingExpr.currValExpr]),
                          ])
                          .toStmt());
    }
  }

  // Calculate host event bindings
  const eventBindings =
      bindingParser.createDirectiveHostEventAsts(directiveSummary, hostBindingSourceSpan);
  if (eventBindings) {
    for (const binding of eventBindings) {
      const bindingExpr = convertActionBinding(
          null, bindingContext, binding.handler, 'b', () => error('Unexpected interpolation'));
      const bindingName = binding.name && sanitizeIdentifier(binding.name);
      const typeName = meta.name;
      const functionName =
          typeName && bindingName ? `${typeName}_${bindingName}_HostBindingHandler` : null;
      const handler = o.fn(
          [new o.FnParam('$event', o.DYNAMIC_TYPE)],
          [...bindingExpr.stmts, new o.ReturnStatement(bindingExpr.allowDefault)], o.INFERRED_TYPE,
          null, functionName);
      statements.push(
          o.importExpr(R3.listener).callFn([o.literal(binding.name), handler]).toStmt());
    }
  }

  if (statements.length > 0) {
    const typeName = meta.name;
    return o.fn(
        [
          new o.FnParam('dirIndex', o.NUMBER_TYPE),
          new o.FnParam('elIndex', o.NUMBER_TYPE),
        ],
        statements, o.INFERRED_TYPE, null, typeName ? `${typeName}_HostBindings` : null);
  }

  return null;
}

function metadataAsSummary(meta: R3DirectiveMetadata): CompileDirectiveSummary {
  // clang-format off
  return {
    hostAttributes: meta.host.attributes,
    hostListeners: meta.host.listeners,
    hostProperties: meta.host.properties,
  } as CompileDirectiveSummary;
  // clang-format on
}


function typeMapToExpressionMap(
    map: Map<string, StaticSymbol>, outputCtx: OutputContext): Map<string, o.Expression> {
  // Convert each map entry into another entry where the value is an expression importing the type.
  const entries = Array.from(map).map(
      ([key, type]): [string, o.Expression] => [key, outputCtx.importExpr(type)]);
  return new Map(entries);
}