better stringify key in LAZY_IN_SYNC

src/constants/error_msgs.ts

@@ -9,16 +9,16 @@ export const MISSING_INJECTABLE_ANNOTATION = 'Missing required @injectable annot
 export const MISSING_INJECT_ANNOTATION = 'Missing required @inject or @multiInject annotation in:';
 export const UNDEFINED_INJECT_ANNOTATION = (name: string) =>
   `@inject called with undefined this could mean that the class ${name} has ` +
-  'a circular dependency problem. You can use a LazyServiceIdentifer to  ' +
+  'a circular dependency problem. You can use a LazyServiceIdentifer to ' +
   'overcome this limitation.';
 export const CIRCULAR_DEPENDENCY = 'Circular dependency found:';
 export const NOT_IMPLEMENTED = 'Sorry, this feature is not fully implemented yet.';
 export const INVALID_BINDING_TYPE = 'Invalid binding type:';
 export const NO_MORE_SNAPSHOTS_AVAILABLE = 'No snapshot available to restore.';
 export const INVALID_MIDDLEWARE_RETURN = 'Invalid return type in middleware. Middleware must return!';
 export const INVALID_FUNCTION_BINDING = 'Value provided to function binding must be a function!';
-export const LAZY_IN_SYNC = (key: unknown) => `You are attempting to construct '${key}' in a synchronous way
- but it has asynchronous dependencies.`;
+export const LAZY_IN_SYNC = (key: unknown) => `You are attempting to construct ${keyToString(key)} in a synchronous way ` +
+  'but it has asynchronous dependencies.';
 
 export const INVALID_TO_SELF_VALUE = 'The toSelf function can only be applied when a constructor is ' +
   'used as service identifier';
@@ -53,3 +53,13 @@ export const CIRCULAR_DEPENDENCY_IN_FACTORY = (factoryType: string, serviceIdent
   `service identifier '${serviceIdentifier}'.`;
 
 export const STACK_OVERFLOW = 'Maximum call stack size exceeded';
+
+function keyToString(key: unknown): string {
+  if (typeof key === 'function') {
+    return `[function/class ${key.name || '<anonymous>'}]`;
+  }
+  if (typeof key === 'symbol') {
+    return key.toString();
+  }
+  return `'${key}'`;
+}

test/constants/error_message.test.ts

@@ -8,4 +8,18 @@ describe('ERROR_MSGS', () => {
     expect(error).eql('@postConstruct error in class a: b');
   });
 
-});
+  it('Should properly stringify symbol in LAZY_IN_SYNC', () => {
+    const error = ERROR_MSGS.LAZY_IN_SYNC(Symbol('a'));
+    expect(error).eql(`You are attempting to construct Symbol(a) in a synchronous way but it has asynchronous dependencies.`);
+  });
+
+  it('Should properly stringify class in LAZY_IN_SYNC', () => {
+    const error = ERROR_MSGS.LAZY_IN_SYNC(class B {});
+    expect(error).eql(`You are attempting to construct [function/class B] in a synchronous way but it has asynchronous dependencies.`);
+  });
+
+  it('Should properly stringify string in LAZY_IN_SYNC', () => {
+    const error = ERROR_MSGS.LAZY_IN_SYNC('c');
+    expect(error).eql(`You are attempting to construct 'c' in a synchronous way but it has asynchronous dependencies.`);
+  });
+});

test/resolution/resolver.test.ts

@@ -1837,8 +1837,7 @@ describe('Resolve', () => {
     container.bind<Constructable>('Constructable').to(Constructable).inSingletonScope()
       .onActivation(() => Promise.resolve());
 
-    expect(() => container.get('Constructable')).to.throw(`You are attempting to construct 'Constructable' in a synchronous way
- but it has asynchronous dependencies.`);
+    expect(() => container.get('Constructable')).to.throw(`You are attempting to construct 'Constructable' in a synchronous way but it has asynchronous dependencies.`);
   });
 
   it('Should force a class with an async post construct to use the async api', async () => {
@@ -1853,8 +1852,7 @@ describe('Resolve', () => {
     const container = new Container();
     container.bind<Constructable>('Constructable').to(Constructable);
 
-    expect(() => container.get('Constructable')).to.throw(`You are attempting to construct 'Constructable' in a synchronous way
- but it has asynchronous dependencies.`);
+    expect(() => container.get('Constructable')).to.throw(`You are attempting to construct 'Constructable' in a synchronous way but it has asynchronous dependencies.`);
   });
 
   it('Should retry promise if first time failed', async () => {
@@ -1906,8 +1904,7 @@ describe('Resolve', () => {
 
     container.onActivation('foo', () => Promise.resolve('baz'));
 
-    expect(() => container.get('foo')).to.throw(`You are attempting to construct 'foo' in a synchronous way
- but it has asynchronous dependencies.`);
+    expect(() => container.get('foo')).to.throw(`You are attempting to construct 'foo' in a synchronous way but it has asynchronous dependencies.`);
   });
 
   it('Should allow onActivation (sync) of a previously binded sync object (without activation)', async () => {
@@ -2530,8 +2527,7 @@ describe('Resolve', () => {
     container.bind<UseDate>('UseDate').to(UseDate);
     container.bind<Date>('Date').toDynamicValue(() => Promise.resolve(new Date()));
 
-    expect(() => container.get<UseDate>('UseDate')).to.throw(`You are attempting to construct 'UseDate' in a synchronous way
- but it has asynchronous dependencies.`);
+    expect(() => container.get<UseDate>('UseDate')).to.throw(`You are attempting to construct 'UseDate' in a synchronous way but it has asynchronous dependencies.`);
   });
 
   it('Should be able to resolve indirect Promise bindings', async () => {
@@ -2569,8 +2565,7 @@ describe('Resolve', () => {
     const container = new Container();
     container.bind<string>('async').toDynamicValue(() => Promise.resolve('foobar'));
 
-    expect(() => container.get<string>('async')).to.throw(`You are attempting to construct 'async' in a synchronous way
- but it has asynchronous dependencies.`);
+    expect(() => container.get<string>('async')).to.throw(`You are attempting to construct 'async' in a synchronous way but it has asynchronous dependencies.`);
   });
 
   it('Should cache a a resolved value on singleton when possible', async () => {
@@ -2597,4 +2592,4 @@ describe('Resolve', () => {
     expect(serviceFromGetAsync).eql(asyncServiceDynamicResolvedValue);
     expect(serviceFromGet).eql(asyncServiceDynamicResolvedValue);
   });
-});
+});