2 files changed, 49 insertions, 1 deletions
diff --git a/cli/rt/11_url.js b/cli/rt/11_url.js
index 202d35e81..cb42e22c7 100644
--- a/cli/rt/11_url.js
+++ b/cli/rt/11_url.js
@@ -222,7 +222,7 @@
       return this.#params
         .map(
           (tuple) =>
-            `${encodeURIComponent(tuple[0])}=${encodeURIComponent(tuple[1])}`,
+            `${encodeSearchParam(tuple[0])}=${encodeSearchParam(tuple[1])}`,
         )
         .join("&");
     }
@@ -792,6 +792,11 @@
     return ["\u0000", "\u0009", "\u000A", "\u000D", "\u0020", "\u0023", "\u0025", "\u002F", "\u003A", "\u003C", "\u003E", "\u003F", "\u0040", "\u005B", "\u005C", "\u005D", "\u005E"].includes(c);
   }
 
+  function charInFormUrlencodedSet(c) {
+    // deno-fmt-ignore
+    return charInUserinfoSet(c) || ["\u0021", "\u0024", "\u0025", "\u0026", "\u0027", "\u0028", "\u0029", "\u002B", "\u002C", "\u007E"].includes(c);
+  }
+
   const encoder = new TextEncoder();
 
   function encodeChar(c) {
@@ -876,6 +881,11 @@
     );
   }
 
+  function encodeSearchParam(s) {
+    return [...s].map((c) => (charInFormUrlencodedSet(c) ? encodeChar(c) : c))
+      .join("").replace("%20", "+");
+  }
+
   window.__bootstrap.url = {
     URL,
     URLSearchParams,
diff --git a/cli/tests/unit/url_search_params_test.ts b/cli/tests/unit/url_search_params_test.ts
index 6965fe128..7698ef1ce 100644
--- a/cli/tests/unit/url_search_params_test.ts
+++ b/cli/tests/unit/url_search_params_test.ts
@@ -1,6 +1,44 @@
 // Copyright 2018-2020 the Deno authors. All rights reserved. MIT license.
 import { unitTest, assert, assertEquals } from "./test_util.ts";
 
+unitTest(function urlSearchParamsWithSpace(): void {
+  const init = { str: "hello world" };
+  const searchParams = new URLSearchParams(init).toString();
+  assertEquals(searchParams, "str=hello+world");
+});
+
+unitTest(function urlSearchParamsWithExclamation(): void {
+  const init = [
+    ["str", "hello, world!"],
+  ];
+  const searchParams = new URLSearchParams(init).toString();
+  assertEquals(searchParams, "str=hello%2C+world%21");
+});
+
+unitTest(function urlSearchParamsWithQuotes(): void {
+  const init = [
+    ["str", "'hello world'"],
+  ];
+  const searchParams = new URLSearchParams(init).toString();
+  assertEquals(searchParams, "str=%27hello+world%27");
+});
+
+unitTest(function urlSearchParamsWithBraket(): void {
+  const init = [
+    ["str", "(hello world)"],
+  ];
+  const searchParams = new URLSearchParams(init).toString();
+  assertEquals(searchParams, "str=%28hello+world%29");
+});
+
+unitTest(function urlSearchParamsWithTilde(): void {
+  const init = [
+    ["str", "hello~world"],
+  ];
+  const searchParams = new URLSearchParams(init).toString();
+  assertEquals(searchParams, "str=hello%7Eworld");
+});
+
 unitTest(function urlSearchParamsInitString(): void {
   const init = "c=4&a=2&b=3&%C3%A1=1";
   const searchParams = new URLSearchParams(init);