refactor(compiler): add type information to `DefinitionMap` (#39961)

This allows the code generation to correspond with a type, which is
helpful for documentation and discoverability purposes. This does not
offer any type-safety with respect to the actually generated code.

PR Close #39961

packages/compiler/src/render3/partial/component.ts

@@ -9,10 +9,11 @@ import * as core from '../../core';
 import {DEFAULT_INTERPOLATION_CONFIG} from '../../ml_parser/interpolation_config';
 import * as o from '../../output/output_ast';
 import {Identifiers as R3} from '../r3_identifiers';
-import {R3ComponentDef, R3ComponentMetadata} from '../view/api';
+import {R3ComponentDef, R3ComponentMetadata, R3UsedDirectiveMetadata} from '../view/api';
 import {createComponentType} from '../view/compiler';
 import {ParsedTemplate} from '../view/template';
 import {DefinitionMap} from '../view/util';
+import {R3DeclareComponentMetadata} from './api';
 
 import {createDirectiveDefinitionMap} from './directive';
 import {toOptionalLiteralArray} from './util';
@@ -34,9 +35,10 @@ export function compileDeclareComponentFromMetadata(
 /**
  * Gathers the declaration fields for a component into a `DefinitionMap`.
  */
-export function createComponentDefinitionMap(
-    meta: R3ComponentMetadata, template: ParsedTemplate): DefinitionMap {
-  const definitionMap = createDirectiveDefinitionMap(meta);
+export function createComponentDefinitionMap(meta: R3ComponentMetadata, template: ParsedTemplate):
+    DefinitionMap<R3DeclareComponentMetadata> {
+  const definitionMap: DefinitionMap<R3DeclareComponentMetadata> =
+      createDirectiveDefinitionMap(meta);
 
   const templateMap = compileTemplateDefinition(template);
 
@@ -76,7 +78,7 @@ export function createComponentDefinitionMap(
  * Compiles the provided template into its partial definition.
  */
 function compileTemplateDefinition(template: ParsedTemplate): o.LiteralMapExpr {
-  const templateMap = new DefinitionMap();
+  const templateMap = new DefinitionMap<R3DeclareComponentMetadata['template']>();
   const templateExpr =
       typeof template.template === 'string' ? o.literal(template.template) : template.template;
   templateMap.set('source', templateExpr);
@@ -94,7 +96,7 @@ function compileUsedDirectiveMetadata(meta: R3ComponentMetadata): o.LiteralArray
       (expr: o.Expression) => expr;
 
   return toOptionalLiteralArray(meta.directives, directive => {
-    const dirMeta = new DefinitionMap();
+    const dirMeta = new DefinitionMap<R3UsedDirectiveMetadata>();
     dirMeta.set('type', wrapType(directive.type));
     dirMeta.set('selector', o.literal(directive.selector));
     dirMeta.set('inputs', toOptionalLiteralArray(directive.inputs, o.literal));

packages/compiler/src/render3/partial/directive.ts

@@ -10,6 +10,7 @@ import {Identifiers as R3} from '../r3_identifiers';
 import {R3DirectiveDef, R3DirectiveMetadata, R3HostMetadata, R3QueryMetadata} from '../view/api';
 import {createDirectiveType} from '../view/compiler';
 import {asLiteral, conditionallyCreateMapObjectLiteral, DefinitionMap} from '../view/util';
+import {R3DeclareDirectiveMetadata, R3DeclareQueryMetadata} from './api';
 import {toOptionalLiteralMap} from './util';
 
 
@@ -29,8 +30,9 @@ export function compileDeclareDirectiveFromMetadata(meta: R3DirectiveMetadata):
  * Gathers the declaration fields for a directive into a `DefinitionMap`. This allows for reusing
  * this logic for components, as they extend the directive metadata.
  */
-export function createDirectiveDefinitionMap(meta: R3DirectiveMetadata): DefinitionMap {
-  const definitionMap = new DefinitionMap();
+export function createDirectiveDefinitionMap(meta: R3DirectiveMetadata):
+    DefinitionMap<R3DeclareDirectiveMetadata> {
+  const definitionMap = new DefinitionMap<R3DeclareDirectiveMetadata>();
 
   definitionMap.set('version', o.literal('0.0.0-PLACEHOLDER'));
 
@@ -77,7 +79,7 @@ export function createDirectiveDefinitionMap(meta: R3DirectiveMetadata): Definit
  * by `R3DeclareQueryMetadata`.
  */
 function compileQuery(query: R3QueryMetadata): o.LiteralMapExpr {
-  const meta = new DefinitionMap();
+  const meta = new DefinitionMap<R3DeclareQueryMetadata>();
   meta.set('propertyName', o.literal(query.propertyName));
   if (query.first) {
     meta.set('first', o.literal(true));
@@ -99,7 +101,7 @@ function compileQuery(query: R3QueryMetadata): o.LiteralMapExpr {
  * in `R3DeclareDirectiveMetadata['host']`
  */
 function compileHostMetadata(meta: R3HostMetadata): o.LiteralMapExpr|null {
-  const hostMetadata = new DefinitionMap();
+  const hostMetadata = new DefinitionMap<NonNullable<R3DeclareDirectiveMetadata['host']>>();
   hostMetadata.set('attributes', toOptionalLiteralMap(meta.attributes, expression => expression));
   hostMetadata.set('listeners', toOptionalLiteralMap(meta.listeners, o.literal));
   hostMetadata.set('properties', toOptionalLiteralMap(meta.properties, o.literal));

packages/compiler/src/render3/view/util.ts

@@ -142,12 +142,17 @@ export function getQueryPredicate(
   }
 }
 
-export class DefinitionMap {
+/**
+ * A representation for an object literal used during codegen of definition objects. The generic
+ * type `T` allows to reference a documented type of the generated structure, such that the
+ * property names that are set can be resolved to their documented declaration.
+ */
+export class DefinitionMap<T = any> {
   values: {key: string, quoted: boolean, value: o.Expression}[] = [];
 
-  set(key: string, value: o.Expression|null): void {
+  set(key: keyof T, value: o.Expression|null): void {
     if (value) {
-      this.values.push({key, value, quoted: false});
+      this.values.push({key: key as string, value, quoted: false});
     }
   }