refactor(ext): align error messages (#25496)

Aligns the error messages in the ext/http and a few messages in the
ext/fetch folder to be in-line with the Deno style guide.

This change-set also removes some unnecessary checks in the 00_serve.ts.
These options were recently removed, so it doesn't make sense to check
for them anymore.

https://github.com/denoland/deno/issues/25269

2 files changed, 17 insertions, 15 deletions

diff --git a/ext/http/00_serve.ts b/ext/http/00_serve.ts
index 6d23685d8..3b9b085a2 100644
--- a/ext/http/00_serve.ts
+++ b/ext/http/00_serve.ts
@@ -123,7 +123,7 @@ function upgradeHttpRaw(req, conn) {
   if (inner._wantsUpgrade) {
     return inner._wantsUpgrade("upgradeHttpRaw", conn);
   }
-  throw new TypeError("upgradeHttpRaw may only be used with Deno.serve");
+  throw new TypeError("'upgradeHttpRaw' may only be used with Deno.serve");
 }
 
 function addTrailers(resp, headerList) {
@@ -170,10 +170,10 @@ class InnerRequest {
 
   _wantsUpgrade(upgradeType, ...originalArgs) {
     if (this.#upgraded) {
-      throw new Deno.errors.Http("already upgraded");
+      throw new Deno.errors.Http("Already upgraded");
     }
     if (this.#external === null) {
-      throw new Deno.errors.Http("already closed");
+      throw new Deno.errors.Http("Already closed");
     }
 
     // upgradeHttpRaw is sync
@@ -257,7 +257,7 @@ class InnerRequest {
 
     if (this.#methodAndUri === undefined) {
       if (this.#external === null) {
-        throw new TypeError("request closed");
+        throw new TypeError("Request closed");
       }
       // TODO(mmastrac): This is quite slow as we're serializing a large number of values. We may want to consider
       // splitting this up into multiple ops.
@@ -315,7 +315,7 @@ class InnerRequest {
     }
     if (this.#methodAndUri === undefined) {
       if (this.#external === null) {
-        throw new TypeError("request closed");
+        throw new TypeError("Request closed");
       }
       this.#methodAndUri = op_http_get_request_method_and_url(this.#external);
     }
@@ -329,7 +329,7 @@ class InnerRequest {
   get method() {
     if (this.#methodAndUri === undefined) {
       if (this.#external === null) {
-        throw new TypeError("request closed");
+        throw new TypeError("Request closed");
       }
       this.#methodAndUri = op_http_get_request_method_and_url(this.#external);
     }
@@ -338,7 +338,7 @@ class InnerRequest {
 
   get body() {
     if (this.#external === null) {
-      throw new TypeError("request closed");
+      throw new TypeError("Request closed");
     }
     if (this.#body !== undefined) {
       return this.#body;
@@ -356,7 +356,7 @@ class InnerRequest {
 
   get headerList() {
     if (this.#external === null) {
-      throw new TypeError("request closed");
+      throw new TypeError("Request closed");
     }
     const headers = [];
     const reqHeaders = op_http_get_request_headers(this.#external);
@@ -457,7 +457,7 @@ function fastSyncResponseOrStream(
   // At this point in the response it needs to be a stream
   if (!ObjectPrototypeIsPrototypeOf(ReadableStreamPrototype, stream)) {
     innerRequest?.close();
-    throw new TypeError("invalid response");
+    throw new TypeError("Invalid response");
   }
   const resourceBacking = getReadableStreamResourceBacking(stream);
   let rid, autoClose;
@@ -619,13 +619,15 @@ function serve(arg1, arg2) {
   if (handler === undefined) {
     if (options === undefined) {
       throw new TypeError(
-        "No handler was provided, so an options bag is mandatory.",
+        "Cannot serve HTTP requests: either a `handler` or `options` must be specified",
       );
     }
     handler = options.handler;
   }
   if (typeof handler !== "function") {
-    throw new TypeError("A handler function must be provided.");
+    throw new TypeError(
+      `Cannot serve HTTP requests: handler must be a function, received ${typeof handler}`,
+    );
   }
   if (options === undefined) {
     options = { __proto__: null };
@@ -679,7 +681,7 @@ function serve(arg1, arg2) {
   if (wantsHttps) {
     if (!options.cert || !options.key) {
       throw new TypeError(
-        "Both cert and key must be provided to enable HTTPS.",
+        "Both 'cert' and 'key' must be provided to enable HTTPS",
       );
     }
     listenOpts.cert = options.cert;
diff --git a/ext/http/01_http.js b/ext/http/01_http.js
index e88684858..9302bd8a0 100644
--- a/ext/http/01_http.js
+++ b/ext/http/01_http.js
@@ -207,7 +207,7 @@ function createRespondWith(
       resp = await resp;
       if (!(ObjectPrototypeIsPrototypeOf(ResponsePrototype, resp))) {
         throw new TypeError(
-          "First argument to respondWith must be a Response or a promise resolving to a Response.",
+          "First argument to 'respondWith' must be a Response or a promise resolving to a Response",
         );
       }
 
@@ -220,7 +220,7 @@ function createRespondWith(
       let respBody = null;
       if (innerResp.body !== null) {
         if (innerResp.body.unusable()) {
-          throw new TypeError("Body is unusable.");
+          throw new TypeError("Body is unusable");
         }
         if (
           ObjectPrototypeIsPrototypeOf(
@@ -295,7 +295,7 @@ function createRespondWith(
         let reader;
         if (resourceBacking) {
           if (respBody.locked) {
-            throw new TypeError("ReadableStream is locked.");
+            throw new TypeError("ReadableStream is locked");
           }
           reader = respBody.getReader(); // Acquire JS lock.
           try {