fix: prevent URLSearchParams.toString() from returning unencoded params when not modified

Author: mattermoran

crates/rust-url/src/lib.rs

@@ -1,6 +1,7 @@
 #![allow(clippy::missing_safety_doc)]
 
 /// Wrapper for the Url crate and a URLSearchParams implementation that enables use from C++.
+use std::cell::RefCell;
 use std::marker::PhantomData;
 use std::slice;
 use url::{form_urlencoded, quirks, Url};
@@ -14,12 +15,15 @@ impl JSUrl {
     fn update_params(&self) {
         if let Some(params) = unsafe { self.params.as_mut() } {
             params.list = self.url.query_pairs().into_owned().collect();
+            if let UrlOrString::Url(_, ref serialized_query_cache) = params.url_or_str {
+                *serialized_query_cache.borrow_mut() = None;
+            }
         }
     }
 }
 
 enum UrlOrString {
-    Url(*mut JSUrl),
+    Url(*mut JSUrl, RefCell<Option<String>>),
     Str(String),
 }
 
@@ -36,7 +40,7 @@ impl JSUrlSearchParams {
     /// This is used in `params_to_string` to hand out a stable reference.
     fn update_url_or_str(&mut self) {
         match self.url_or_str {
-            UrlOrString::Url(url) => {
+            UrlOrString::Url(url, ref serialized_query_cache) => {
                 let url = unsafe { url.as_mut().unwrap() };
                 if self.list.is_empty() {
                     url.url.set_query(None);
@@ -45,6 +49,7 @@ impl JSUrlSearchParams {
                     pairs.clear();
                     pairs.extend_pairs(self.list.iter());
                 }
+                *serialized_query_cache.borrow_mut() = None;
             }
             UrlOrString::Str(_) => {
                 let str = if self.list.is_empty() {
@@ -222,7 +227,7 @@ pub unsafe extern "C" fn url_search_params(url: *mut JSUrl) -> *mut JSUrlSearchP
     if url.params.is_null() {
         url.params = Box::into_raw(Box::new(JSUrlSearchParams {
             list: url.url.query_pairs().into_owned().collect(),
-            url_or_str: UrlOrString::Url(url),
+            url_or_str: UrlOrString::Url(url, RefCell::new(None)),
         }));
     }
     url.params
@@ -401,12 +406,19 @@ pub extern "C" fn params_sort(params: &mut JSUrlSearchParams) {
 #[no_mangle]
 pub extern "C" fn params_to_string(params: &JSUrlSearchParams) -> SpecSlice<'_> {
     match &params.url_or_str {
-        UrlOrString::Url(url) => {
-            let url = unsafe { url.as_mut().unwrap() };
-            match url.url.query() {
-                Some(query) => query.into(),
-                None => "".into(),
+        UrlOrString::Url(_, serialized_query_cache) => {
+            if serialized_query_cache.borrow().is_none() {
+                let strict_string = form_urlencoded::Serializer::new(String::new())
+                    .extend_pairs(&params.list)
+                    .finish();
+
+                *serialized_query_cache.borrow_mut() = Some(strict_string);
             }
+
+            let cache = serialized_query_cache.borrow();
+            let str_ref = cache.as_ref().unwrap();
+
+            SpecSlice::new(str_ref.as_ptr(), str_ref.len())
         }
         UrlOrString::Str(str) => str.as_str().into(),
     }

tests/wpt-harness/expectations/url/urlsearchparams-stringifier.any.js.json

@@ -36,7 +36,7 @@
     "status": "PASS"
   },
   "URLSearchParams connected to URL": {
-    "status": "FAIL"
+    "status": "PASS"
   },
   "URLSearchParams must not do newline normalization": {
     "status": "PASS"