Merge pull request nestjs#3653 from jacob87o2/fix-unknown-dependency-exception

fix(core): fix unknown dependency exception (symbols)

Author: kamilmysliwiec

integration/injector/e2e/property-injection.spec.ts

@@ -3,6 +3,7 @@ import { expect } from 'chai';
 import { DependencyService } from '../src/properties/dependency.service';
 import { PropertiesModule } from '../src/properties/properties.module';
 import { PropertiesService } from '../src/properties/properties.service';
+import { UnknownDependenciesException } from '@nestjs/core/errors/exceptions/unknown-dependencies.exception';
 
 describe('Injector', () => {
   it('should resolve property-based dependencies', async () => {
@@ -14,5 +15,30 @@ describe('Injector', () => {
 
     expect(app.get(PropertiesService).service).to.be.eql(dependency);
     expect(app.get(PropertiesService).token).to.be.true;
+    expect(app.get(PropertiesService).symbolToken).to.be.true;
+  });
+
+  it('should throw UnknownDependenciesException when dependency is not met', async () => {
+    let exception;
+
+    try {
+      const builder = Test.createTestingModule({
+        providers: [
+          DependencyService,
+          PropertiesService,
+          {
+            provide: 'token',
+            useValue: true,
+          },
+          // symbol token is missing here
+        ],
+      });
+      const app = await builder.compile();
+      app.get(DependencyService);
+    } catch (e) {
+      exception = e;
+    }
+
+    expect(exception).to.be.instanceOf(UnknownDependenciesException);
   });
 });

integration/injector/src/properties/properties.module.ts

@@ -1,6 +1,6 @@
 import { Module } from '@nestjs/common';
 import { DependencyService } from './dependency.service';
-import { PropertiesService } from './properties.service';
+import { PropertiesService, SYMBOL_TOKEN } from './properties.service';
 
 @Module({
   providers: [
@@ -10,6 +10,10 @@ import { PropertiesService } from './properties.service';
       provide: 'token',
       useValue: true,
     },
+    {
+      provide: SYMBOL_TOKEN,
+      useValue: true,
+    },
   ],
 })
 export class PropertiesModule {}

integration/injector/src/properties/properties.service.ts

@@ -1,8 +1,11 @@
 import { Inject, Injectable } from '@nestjs/common';
 import { DependencyService } from './dependency.service';
 
+export const SYMBOL_TOKEN = Symbol('token');
+
 @Injectable()
 export class PropertiesService {
   @Inject() service: DependencyService;
   @Inject('token') token: boolean;
+  @Inject(SYMBOL_TOKEN) symbolToken: boolean;
 }

packages/core/errors/messages.ts

@@ -10,7 +10,7 @@ import { Module } from '../injector/module';
  * Returns the name of an instance
  * @param instance The instance which should get the name from
  */
-const getInstanceName = (instance: unknown) =>
+const getInstanceName = (instance: unknown): string =>
   instance && (instance as Type<any>).name;
 
 /**
@@ -19,13 +19,13 @@ const getInstanceName = (instance: unknown) =>
  * (= injection token). As fallback it returns '+'
  * @param dependency The dependency whichs name should get displayed
  */
-const getDependencyName = (dependency: InjectorDependency) =>
+const getDependencyName = (dependency: InjectorDependency): string =>
   // use class name
   getInstanceName(dependency) ||
   // use injection token (symbol)
   (isSymbol(dependency) && dependency.toString()) ||
   // use string directly
-  dependency ||
+  (dependency as string) ||
   // otherwise
   '+';
 
@@ -49,15 +49,16 @@ export const UNKNOWN_DEPENDENCIES_MESSAGE = (
     key,
   } = unknownDependencyContext;
   const moduleName = getModuleName(module) || 'Module';
+  const dependencyName = getDependencyName(name);
 
   let message = `Nest can't resolve dependencies of the ${type.toString()}`;
 
   const potentialSolutions = `\n
 Potential solutions:
-- If ${name} is a provider, is it part of the current ${moduleName}?
-- If ${name} is exported from a separate @Module, is that module imported within ${moduleName}?
+- If ${dependencyName} is a provider, is it part of the current ${moduleName}?
+- If ${dependencyName} is exported from a separate @Module, is that module imported within ${moduleName}?
   @Module({
-    imports: [ /* the Module containing ${name} */ ]
+    imports: [ /* the Module containing ${dependencyName} */ ]
   })
 `;
 
@@ -70,7 +71,7 @@ Potential solutions:
 
   message += ` (`;
   message += dependenciesName.join(', ');
-  message += `). Please make sure that the argument ${name} at index [${index}] is available in the ${getModuleName(
+  message += `). Please make sure that the argument ${dependencyName} at index [${index}] is available in the ${getModuleName(
     module,
   )} context.`;
   message += potentialSolutions;

packages/core/injector/injector.ts

@@ -55,7 +55,7 @@ export interface InjectorDependencyContext {
   /**
    * The name of the function or injection token
    */
-  name?: string;
+  name?: string | symbol;
   /**
    * The index of the dependency which gets injected
    * from the dependencies array
@@ -411,7 +411,7 @@ export class Injector {
   }
 
   public async lookupComponent<T = any>(
-    providers: Map<string, InstanceWrapper>,
+    providers: Map<string | symbol, InstanceWrapper>,
     module: Module,
     dependencyContext: InjectorDependencyContext,
     wrapper: InstanceWrapper<T>,