2 files changed, 43 insertions, 5 deletions
diff --git a/cli/tests/unit/url_search_params_test.ts b/cli/tests/unit/url_search_params_test.ts
index 41b277129..dc0e8bd85 100644
--- a/cli/tests/unit/url_search_params_test.ts
+++ b/cli/tests/unit/url_search_params_test.ts
@@ -49,10 +49,39 @@ unitTest(function urlSearchParamsInitString(): void {
 });
 
 unitTest(function urlSearchParamsInitStringWithPlusCharacter(): void {
-  const init = "q=a+b";
-  const searchParams = new URLSearchParams(init);
-  assertEquals(searchParams.toString(), init);
-  assertEquals(searchParams.get("q"), "a b");
+  let params = new URLSearchParams("q=a+b");
+  assertEquals(params.toString(), "q=a+b");
+  assertEquals(params.get("q"), "a b");
+
+  params = new URLSearchParams("q=a+b+c");
+  assertEquals(params.toString(), "q=a+b+c");
+  assertEquals(params.get("q"), "a b c");
+});
+
+unitTest(function urlSearchParamsInitStringWithMalformedParams(): void {
+  // These test cases are copied from Web Platform Tests
+  // https://github.com/web-platform-tests/wpt/blob/54c6d64/url/urlsearchparams-constructor.any.js#L60-L80
+  let params = new URLSearchParams("id=0&value=%");
+  assert(params != null, "constructor returned non-null value.");
+  assert(params.has("id"), 'Search params object has name "id"');
+  assert(params.has("value"), 'Search params object has name "value"');
+  assertEquals(params.get("id"), "0");
+  assertEquals(params.get("value"), "%");
+
+  params = new URLSearchParams("b=%2sf%2a");
+  assert(params != null, "constructor returned non-null value.");
+  assert(params.has("b"), 'Search params object has name "b"');
+  assertEquals(params.get("b"), "%2sf*");
+
+  params = new URLSearchParams("b=%2%2af%2a");
+  assert(params != null, "constructor returned non-null value.");
+  assert(params.has("b"), 'Search params object has name "b"');
+  assertEquals(params.get("b"), "%2*f*");
+
+  params = new URLSearchParams("b=%%2a");
+  assert(params != null, "constructor returned non-null value.");
+  assert(params.has("b"), 'Search params object has name "b"');
+  assertEquals(params.get("b"), "%*");
 });
 
 unitTest(function urlSearchParamsInitIterable(): void {
diff --git a/op_crates/web/11_url.js b/op_crates/web/11_url.js
index f2d12f5be..d60f9769a 100644
--- a/op_crates/web/11_url.js
+++ b/op_crates/web/11_url.js
@@ -37,7 +37,16 @@
   }
 
   function decodeSearchParam(p) {
-    return decodeURIComponent(p.replace(/\+/g, " "));
+    const s = p.replaceAll("+", " ");
+    const decoder = new TextDecoder();
+
+    return s.replace(/(%[0-9a-f]{2})+/gi, (matched) => {
+      const buf = new Uint8Array(Math.ceil(matched.length / 3));
+      for (let i = 0, offset = 0; i < matched.length; i += 3, offset += 1) {
+        buf[offset] = parseInt(matched.slice(i + 1, i + 3), 16);
+      }
+      return decoder.decode(buf);
+    });
   }
 
   const urls = new WeakMap();