Improve HTTPError messages (#333)

Author: sholladay

source/errors/HTTPError.ts

@@ -6,12 +6,12 @@ export class HTTPError extends Error {
 	public options: NormalizedOptions;
 
 	constructor(response: Response, request: Request, options: NormalizedOptions) {
-		// Set the message to the status text, such as Unauthorized,
-		// with some fallbacks. This message should never be undefined.
-		super(
-			response.statusText ||
-				String(response.status === 0 || response.status ? response.status : 'Unknown response error')
-		);
+		const code = (response.status || response.status === 0) ? response.status : '';
+		const title = response.statusText || '';
+		const status = `${code} ${title}`.trim();
+		const reason = status ? `status code ${status}` : 'an unknown error';
+
+		super(`Request failed with ${reason}`);
 
 		this.name = 'HTTPError';
 		this.response = response;

test/browser.ts

@@ -405,7 +405,7 @@ test('retry with body', withPage, async (t: ExecutionContext, page: Page) => {
 				retry: 2
 			});
 		}, server.url),
-		{message: /HTTPError: Bad Gateway/}
+		{message: /HTTPError: Request failed with status code 502 Bad Gateway/}
 	);
 
 	t.is(requestCount, 2);

test/hooks.ts

@@ -483,7 +483,7 @@ test('beforeRetry hook with parseJson and error.response.json()', async t => {
 				beforeRetry: [
 					async ({error, retryCount}) => {
 						t.true(error instanceof ky.HTTPError);
-						t.is(error.message, 'Bad Gateway');
+						t.is(error.message, 'Request failed with status code 502 Bad Gateway');
 						t.true((error as HTTPError).response instanceof Response);
 						t.deepEqual(await (error as HTTPError).response.json(), {awesome: true});
 						t.is(retryCount, 1);

test/http-error.ts

@@ -25,7 +25,7 @@ test('HTTPError handles undefined response.statusText', t => {
 		createFakeResponse({statusText: undefined, status})
 	);
 
-	t.is(error.message, String(status));
+	t.is(error.message, 'Request failed with status code 500');
 });
 
 test('HTTPError handles undefined response.status', t => {
@@ -36,7 +36,7 @@ test('HTTPError handles undefined response.status', t => {
 		createFakeResponse({statusText: undefined, status: undefined})
 	);
 
-	t.is(error.message, 'Unknown response error');
+	t.is(error.message, 'Request failed with an unknown error');
 });
 
 test('HTTPError handles a response.status of 0', t => {
@@ -46,5 +46,5 @@ test('HTTPError handles a response.status of 0', t => {
 		createFakeResponse({statusText: undefined, status: 0})
 	);
 
-	t.is(error.message, '0');
+	t.is(error.message, 'Request failed with status code 0');
 });