grpc-js: Add type predicate to fix errors for isFunction

zereraz · zereraz · commit 923b44bb1c22 · 2021-04-28T00:18:35.000+05:30
diff --git a/packages/grpc-js/src/client.ts b/packages/grpc-js/src/client.ts
@@ -55,7 +55,7 @@ const INTERCEPTOR_SYMBOL = Symbol();
 const INTERCEPTOR_PROVIDER_SYMBOL = Symbol();
 const CALL_INVOCATION_TRANSFORMER_SYMBOL = Symbol();
 
-function isFunction<ResponseType>(arg: Metadata | CallOptions | UnaryCallback<ResponseType>): boolean {
+function isFunction<ResponseType>(arg: Metadata | CallOptions | UnaryCallback<ResponseType> | undefined): arg is UnaryCallback<ResponseType>{
   return Object.prototype.toString.call(arg) === '[object Function]'
 }
 

Original file line number	Diff line number	Diff line change
`@@ -55,7 +55,7 @@ const INTERCEPTOR_SYMBOL = Symbol();`
`55`	`55`	`const INTERCEPTOR_PROVIDER_SYMBOL = Symbol();`
`56`	`56`	`const CALL_INVOCATION_TRANSFORMER_SYMBOL = Symbol();`
`57`	`57`
`58`		`-function isFunction<ResponseType>(arg: Metadata \| CallOptions \| UnaryCallback<ResponseType>): boolean {`
	`58`	`+function isFunction<ResponseType>(arg: Metadata \| CallOptions \| UnaryCallback<ResponseType> \| undefined): arg is UnaryCallback<ResponseType>{`
`59`	`59`	`return Object.prototype.toString.call(arg) === '[object Function]'`
`60`	`60`	`}`
`61`	`61`