Add further tests for error handling, improving overall coverage to 94.2%

Author: briward

README.md

@@ -129,23 +129,21 @@ Errors thrown in middleware are picked up and added to the `Context` object, all
 ```ts
 import { type Context, NotFound } from "jsr:@raptor/framework";
 
+// Simulate an application error.
 app.add((context: Context) => {
   throw new NotFound();
 });
 
+// Catch our error and handle response.
 app.add((context: Context) => {
   const { error, response } = context;
 
-  if (!error) {
-    return;
-  };
-
-  if (error.status === 404) {
-    return '<h1>No page could be found</h1>';
+  if (error?.status === 404) {
+    return '<h1>No page could be found</h1>'
   }
 
   response.status = 500;
-  return '<h1>There was a server error</h1>';
+  return '<h1>There was a server error</h1>'
 });
 ```
 
@@ -156,6 +154,8 @@ The following errors are currently available to import and throw from within the
 * `ServerError`
 * `TypeError`
 
+You can create your own errors by implementing the `Error` interface.
+
 # Deployment
 
 ## Deno Deploy

src/http/response.ts

@@ -29,17 +29,4 @@ export default class HttpResponse extends Response {
   override clone(): HttpResponse {
     return this;
   }
-
-  /**
-   * Check if the response has body content.
-   *
-   * @returns Whether the response has body content.
-   */
-  public hasBody(): boolean {
-    const length = this.headers.get("content-length");
-
-    if (!length) return false;
-
-    return parseInt(length) > 0;
-  }
 }

tests/kernel.test.ts

@@ -1,6 +1,10 @@
 import { assertEquals } from "jsr:@std/assert";
 
-import { type Context, Kernel } from "../mod.ts";
+import Kernel from "../src/kernel.ts";
+import NotFound from "../src/error/not-found.ts";
+import type Context from "../src/http/context.ts";
+import BadRequest from "../src/error/bad-request.ts";
+import ServerError from "../src/error/server-error.ts";
 
 const APP_URL = "http://localhost:8000";
 
@@ -68,3 +72,66 @@ Deno.test("test middleware next callback functionality", async () => {
 
   assertEquals(await response.text(), "Hello from the second middleware");
 });
+
+Deno.test("test middleware catches 404 error", async () => {
+  const app = new Kernel();
+
+  app.add((_ctx: Context) => {
+    throw new NotFound();
+  });
+
+  app.add((ctx: Context) => {
+    const { error } = ctx;
+
+    if (error?.status === 404) {
+      return 'Page not found';
+    }
+  });
+
+  const response = await app.respond(new Request(APP_URL));
+
+  assertEquals(await response.text(), "Page not found");
+});
+
+Deno.test("test middleware catches server error", async () => {
+  const app = new Kernel();
+
+  app.add((_ctx: Context) => {
+    throw new ServerError();
+  });
+
+  app.add((ctx: Context) => {
+    const { error } = ctx;
+
+    if (error?.status === 500) {
+      return 'Internal server error';
+    }
+  });
+
+  const response = await app.respond(new Request(APP_URL));
+
+  assertEquals(await response.text(), "Internal server error");
+});
+
+Deno.test("test middleware catches bad request error", async () => {
+  const app = new Kernel();
+
+  app.add((_ctx: Context) => {
+    throw new BadRequest([
+      'There was an error in validation of field #1',
+      'There was an error in validation of field #2'
+    ]);
+  });
+
+  app.add((ctx: Context) => {
+    const { error } = ctx;
+
+    if (error?.status === 400) {
+      return 'Bad request';
+    }
+  });
+
+  const response = await app.respond(new Request(APP_URL));
+
+  assertEquals(await response.text(), "Bad request");
+});