fix(ext/fetch): do not truncate field value in EventSource

denoland · Feb 10, 2024 · 0662c23 · 0662c23
1 parent f5e46c9
commit 0662c23
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Showing 3 changed files with 35 additions and 3 deletions.
diff --git a/ext/fetch/27_eventsource.js b/ext/fetch/27_eventsource.js
@@ -16,7 +16,6 @@ const {
   StringPrototypeIncludes,
   StringPrototypeIndexOf,
   StringPrototypeSlice,
-  StringPrototypeSplit,
   StringPrototypeStartsWith,
   StringPrototypeToLowerCase,
   Symbol,
@@ -289,10 +288,12 @@ class EventSource extends EventTarget {
           } else if (StringPrototypeStartsWith(chunk, ":")) {
             continue;
           } else {
+            const colonIndex = StringPrototypeIndexOf(chunk, ":");
             let field = chunk;
             let value = "";
-            if (StringPrototypeIncludes(chunk, ":")) {
-              ({ 0: field, 1: value } = StringPrototypeSplit(chunk, ":"));
+            if (colonIndex !== -1) {
+              field = StringPrototypeSlice(chunk, 0, colonIndex);
+              value = StringPrototypeSlice(chunk, colonIndex + 1);
               if (StringPrototypeStartsWith(value, " ")) {
                 value = StringPrototypeSlice(value, 1);
               }

diff --git a/tests/integration/js_unit_tests.rs b/tests/integration/js_unit_tests.rs
@@ -29,6 +29,7 @@ util::unit_test_factory!(
     error_stack_test,
     error_test,
     esnext_test,
+    event_source_test,
     event_target_test,
     event_test,
     fetch_test,

diff --git a/tests/unit/event_source_test.ts b/tests/unit/event_source_test.ts
@@ -0,0 +1,30 @@
+// Copyright 2018-2024 the Deno authors. All rights reserved. MIT license.
+import { assertStrictEquals } from "./test_util.ts";
+
+Deno.test(
+  { permissions: { net: ["127.0.0.1"] } },
+  async function eventSourceColonInMessage() {
+    const portDeferred = Promise.withResolvers<number>();
+
+    await using _server = Deno.serve({
+      handler: () => {
+        const readable = ReadableStream.from([
+          new TextEncoder().encode('data: {"key":"value"}\n\n'),
+        ]);
+        return new Response(readable, {
+          headers: { "content-type": "text/event-stream" },
+        });
+      },
+      onListen: ({ port }) => portDeferred.resolve(port),
+      hostname: "127.0.0.1",
+      port: 0,
+    });
+
+    const port = await portDeferred.promise;
+    const eventSource = new EventSource(`http://127.0.0.1:${port}/`);
+    const event = await new Promise<MessageEvent>((resolve) =>
+      eventSource.onmessage = resolve
+    );
+    assertStrictEquals(event.data, '{"key":"value"}');
+  },
+);