feat(compiler): enabled strict checking of parameters to an `@Injectable` (#19412)

Added the compiler options `strictInjectionParameters` that defaults
to `false`. If enabled the compiler will report errors for parameters
of an `@Injectable` that cannot be determined instead of generating a
warning.

This is planned to be switched to default to `true` for Angular 6.0.

packages/compiler-cli/src/transformers/api.ts

@@ -52,6 +52,14 @@ export interface CompilerOptions extends ts.CompilerOptions {
   // Don't produce .ngfactory.ts or .ngstyle.ts files
   skipTemplateCodegen?: boolean;
 
+  // Always report errors when the type of a parameter supplied whose injection type cannot
+  // be determined. When this value option is not provided or is `false`, constructor
+  // parameters of classes marked with `@Injectable` whose type cannot be resolved will
+  // produce a warning. With this option `true`, they produce an error. When this option is
+  // not provided is treated as if it were `false`. In Angular 6.0, if this option is not
+  // provided, it will be treated as `true`.
+  strictInjectionParameters?: boolean;
+
   // Whether to generate a flat module index of the given name and the corresponding
   // flat module metadata. This option is intended to be used when creating flat
   // modules similar to how `@angular/core` and `@angular/common` are packaged.

packages/compiler/src/aot/compiler_factory.ts

@@ -69,6 +69,7 @@ export function createAotCompiler(compilerHost: AotCompilerHost, options: AotCom
     enableLegacyTemplate: options.enableLegacyTemplate === true,
     missingTranslation: options.missingTranslation,
     preserveWhitespaces: options.preserveWhitespaces,
+    strictInjectionParameters: options.strictInjectionParameters,
   });
   const normalizer = new DirectiveNormalizer(
       {get: (url: string) => compilerHost.loadResource(url)}, urlResolver, htmlParser, config);

packages/compiler/src/aot/compiler_options.ts

@@ -19,4 +19,5 @@ export interface AotCompilerOptions {
   preserveWhitespaces?: boolean;
   fullTemplateTypeCheck?: boolean;
   allowEmptyCodegenFiles?: boolean;
+  strictInjectionParameters?: boolean;
 }

packages/compiler/src/config.ts

@@ -21,17 +21,18 @@ export class CompilerConfig {
   public jitDevMode: boolean;
   public missingTranslation: MissingTranslationStrategy|null;
   public preserveWhitespaces: boolean;
+  public strictInjectionParameters: boolean;
 
   constructor(
       {defaultEncapsulation = ViewEncapsulation.Emulated, useJit = true, jitDevMode = false,
-       missingTranslation, enableLegacyTemplate, preserveWhitespaces}: {
+       missingTranslation, enableLegacyTemplate, preserveWhitespaces, strictInjectionParameters}: {
         defaultEncapsulation?: ViewEncapsulation,
         useJit?: boolean,
         jitDevMode?: boolean,
         missingTranslation?: MissingTranslationStrategy,
         enableLegacyTemplate?: boolean,
         preserveWhitespaces?: boolean,
-        fullTemplateTypeCheck?: boolean
+        strictInjectionParameters?: boolean,
       } = {}) {
     this.defaultEncapsulation = defaultEncapsulation;
     this.useJit = !!useJit;
@@ -39,6 +40,7 @@ export class CompilerConfig {
     this.missingTranslation = missingTranslation || null;
     this.enableLegacyTemplate = enableLegacyTemplate === true;
     this.preserveWhitespaces = preserveWhitespacesDefault(noUndefined(preserveWhitespaces));
+    this.strictInjectionParameters = strictInjectionParameters === true;
   }
 }
 

packages/compiler/src/metadata_resolver.ts

@@ -886,10 +886,10 @@ export class CompileMetadataResolver {
           dependenciesMetadata.map((dep) => dep ? stringifyType(dep.token) : '?').join(', ');
       const message =
           `Can't resolve all parameters for ${stringifyType(typeOrFunc)}: (${depsTokens}).`;
-      if (throwOnUnknownDeps) {
+      if (throwOnUnknownDeps || this._config.strictInjectionParameters) {
         this._reportError(syntaxError(message), typeOrFunc);
       } else {
-        this._console.warn(`Warning: ${message} This will become an error in Angular v5.x`);
+        this._console.warn(`Warning: ${message} This will become an error in Angular v6.x`);
       }
     }
 

packages/compiler/test/aot/compiler_spec.ts

@@ -205,10 +205,30 @@ describe('compiler (unbundled Angular)', () => {
       const warnSpy = spyOn(console, 'warn');
       compile([FILES, angularFiles]);
       expect(warnSpy).toHaveBeenCalledWith(
-          `Warning: Can't resolve all parameters for MyService in /app/app.ts: (?). This will become an error in Angular v5.x`);
+          `Warning: Can't resolve all parameters for MyService in /app/app.ts: (?). This will become an error in Angular v6.x`);
 
     });
 
+    it('should error if not all arguments of an @Injectable class can be resolved if strictInjectionParamters is true',
+       () => {
+         const FILES: MockDirectory = {
+           app: {
+             'app.ts': `
+                import {Injectable} from '@angular/core';
+
+                @Injectable()
+                export class MyService {
+                  constructor(a: boolean) {}
+                }
+              `
+           }
+         };
+         const warnSpy = spyOn(console, 'warn');
+         expect(() => compile([FILES, angularFiles], {strictInjectionParameters: true}))
+             .toThrowError(`Can't resolve all parameters for MyService in /app/app.ts: (?).`);
+         expect(warnSpy).not.toHaveBeenCalled();
+       });
+
     it('should be able to suppress a null access', () => {
       const FILES: MockDirectory = {
         app: {