Make FunctionsError class public

Author: dlarocque

common/api-review/functions.api.md

@@ -5,6 +5,7 @@
 ```ts
 
 import { FirebaseApp } from '@firebase/app';
+import { FirebaseError } from '@firebase/util';
 
 // @public
 export function connectFunctionsEmulator(functionsInstance: Functions, host: string, port: number): void;
@@ -16,6 +17,14 @@ export interface Functions {
     region: string;
 }
 
+// @public
+export class FunctionsError extends FirebaseError {
+    constructor(
+    code: FunctionsErrorCodeCore, message?: string,
+    details?: unknown);
+    readonly details?: unknown;
+}
+
 // @public
 export type FunctionsErrorCode = `functions/${FunctionsErrorCodeCore}`;
 

docs-devsite/functions.functionserror.md

@@ -9,33 +9,50 @@ overwritten. Changes should be made in the source code at
 https://github.com/firebase/firebase-js-sdk
 {% endcomment %}
 
-# FunctionsError interface
-An error returned by the Firebase Functions client SDK.
+# FunctionsError class
+An explicit error that can be thrown from a handler to send an error to the client that called the function.
+
+See [FunctionsErrorCode](./functions.md#functionserrorcode) for full documentation of codes.
 
 <b>Signature:</b>
 
 ```typescript
-export interface FunctionsError extends FirebaseError 
+export declare class FunctionsError extends FirebaseError 
 ```
 <b>Extends:</b> [FirebaseError](./util.firebaseerror.md#firebaseerror_class)
 
-## Properties
+## Constructors
 
-|  Property | Type | Description |
+|  Constructor | Modifiers | Description |
 |  --- | --- | --- |
-|  [code](./functions.functionserror.md#functionserrorcode) | [FunctionsErrorCode](./functions.md#functionserrorcode) | A standard error code that will be returned to the client. This also determines the HTTP status code of the response, as defined in code.proto. |
-|  [details](./functions.functionserror.md#functionserrordetails) | unknown | Extra data to be converted to JSON and included in the error response. |
+|  [(constructor)(code, message, details)](./functions.functionserror.md#functionserrorconstructor) |  | Constructs a new instance of the <code>FunctionsError</code> class |
+
+## Properties
 
-## FunctionsError.code
+|  Property | Modifiers | Type | Description |
+|  --- | --- | --- | --- |
+|  [details](./functions.functionserror.md#functionserrordetails) |  | unknown | Extra data to be converted to JSON and included in the error response. |
 
-A standard error code that will be returned to the client. This also determines the HTTP status code of the response, as defined in code.proto.
+## FunctionsError.(constructor)
+
+Constructs a new instance of the `FunctionsError` class
 
 <b>Signature:</b>
 
 ```typescript
-readonly code: FunctionsErrorCode;
+constructor(
+    code: FunctionsErrorCode, message?: string, 
+    details?: unknown);
 ```
 
+#### Parameters
+
+|  Parameter | Type | Description |
+|  --- | --- | --- |
+|  code | [FunctionsErrorCode](./functions.md#functionserrorcodecore) |  |
+|  message | string |  |
+|  details | unknown |  |
+
 ## FunctionsError.details
 
 Extra data to be converted to JSON and included in the error response.

docs-devsite/functions.md

@@ -23,12 +23,17 @@ Cloud Functions for Firebase
 |  [httpsCallable(functionsInstance, name, options)](./functions.md#httpscallable_1dd297c) | Returns a reference to the callable HTTPS trigger with the given name. |
 |  [httpsCallableFromURL(functionsInstance, url, options)](./functions.md#httpscallablefromurl_7af6987) | Returns a reference to the callable HTTPS trigger with the specified url. |
 
+## Classes
+
+|  Class | Description |
+|  --- | --- |
+|  [FunctionsError](./functions.functionserror.md#functionserror_class) | An explicit error that can be thrown from a handler to send an error to the client that called the function.<!-- -->See [FunctionsErrorCode](./functions.md#functionserrorcode) for full documentation of codes. |
+
 ## Interfaces
 
 |  Interface | Description |
 |  --- | --- |
 |  [Functions](./functions.functions.md#functions_interface) | A <code>Functions</code> instance. |
-|  [FunctionsError](./functions.functionserror.md#functionserror_interface) | An error returned by the Firebase Functions client SDK. |
 |  [HttpsCallableOptions](./functions.httpscallableoptions.md#httpscallableoptions_interface) | An interface for metadata about how calls should be executed. |
 |  [HttpsCallableResult](./functions.httpscallableresult.md#httpscallableresult_interface) | An <code>HttpsCallableResult</code> wraps a single result from a function call. |
 

packages/functions/src/api.ts

@@ -32,6 +32,7 @@ import {
   getDefaultEmulatorHostnameAndPort
 } from '@firebase/util';
 
+export { FunctionsError } from './error';
 export * from './public-types';
 
 /**

packages/functions/src/error.ts

@@ -51,6 +51,10 @@ const errorCodeMap: { [name: string]: FunctionsErrorCode } = {
 /**
  * An explicit error that can be thrown from a handler to send an error to the
  * client that called the function.
+ *
+ * See {@link FunctionsErrorCode} for full documentation of codes.
+ *
+ * @public
  */
 export class FunctionsError extends FirebaseError {
   constructor(
@@ -66,7 +70,10 @@ export class FunctionsError extends FirebaseError {
     readonly details?: unknown
   ) {
     super(`${FUNCTIONS_TYPE}/${code}`, message || '');
-    // TODO (dlarocque): Set this to be the root of the stack trace.
+
+    // Since the FirebaseError constructor sets the prototype of `this` to FirebaseError.prototype,
+    // we also have to do it in all subclasses to allow for correct `instanceof` checks.
+    Object.setPrototypeOf(this, FunctionsError.prototype);
   }
 }