Auto merge of #26810 - CYBAI:fix-infinite-stream, r=<try>

Fix infinite stream and its missing incumbent script environment when newing a new stream

---
- [x] `./mach build -d` does not report any errors
- [x] `./mach test-tidy` does not report any errors
- [x] These changes fix #26807
- [ ] There are tests for these changes OR
- [ ] These changes do not require tests because ___

components/script/body.rs

@@ -42,6 +42,7 @@ use js::typedarray::{ArrayBuffer, CreateWith};
 use mime::{self, Mime};
 use net_traits::request::{BodyChunkRequest, BodySource as NetBodySource, RequestBody};
 use script_traits::serializable::BlobImpl;
+use std::cell::Cell;
 use std::ptr;
 use std::rc::Rc;
 use std::str;
@@ -72,6 +73,7 @@ struct TransmitBodyConnectHandler {
     bytes_sender: Option<IpcSender<Vec<u8>>>,
     control_sender: IpcSender<BodyChunkRequest>,
     in_memory: Option<Vec<u8>>,
+    in_memory_done: Cell<bool>,
     source: BodySource,
 }
 
@@ -91,6 +93,7 @@ impl TransmitBodyConnectHandler {
             bytes_sender: None,
             control_sender,
             in_memory,
+            in_memory_done: Cell::new(false),
             source,
         }
     }
@@ -155,6 +158,12 @@ impl TransmitBodyConnectHandler {
 
     /// The entry point to <https://fetch.spec.whatwg.org/#concept-request-transmit-body>
     fn transmit_body_chunk(&mut self) {
+        if self.in_memory_done.get() {
+            // Step 5.1.3
+            let _ = self.control_sender.send(BodyChunkRequest::Done);
+            return;
+        }
+
         let stream = self.stream.clone();
         let control_sender = self.control_sender.clone();
         let bytes_sender = self
@@ -165,6 +174,9 @@ impl TransmitBodyConnectHandler {
         // In case of the data being in-memory, send everything in one chunk, by-passing SpiderMonkey.
         if let Some(bytes) = self.in_memory.clone() {
             let _ = bytes_sender.send(bytes);
+            // Mark this body as `done` so that we can correctly make it as Done in next tick
+            // and we won't leave this stream too early
+            self.in_memory_done.set(true);
             return;
         }
 

components/script/dom/readablestream.rs

@@ -6,7 +6,7 @@ use crate::dom::bindings::conversions::{ConversionBehavior, ConversionResult};
 use crate::dom::bindings::error::Error;
 use crate::dom::bindings::reflector::{reflect_dom_object, DomObject, Reflector};
 use crate::dom::bindings::root::DomRoot;
-use crate::dom::bindings::settings_stack::AutoEntryScript;
+use crate::dom::bindings::settings_stack::{AutoEntryScript, AutoIncumbentScript};
 use crate::dom::bindings::utils::get_dictionary_property;
 use crate::dom::globalscope::GlobalScope;
 use crate::dom::promise::Promise;
@@ -118,6 +118,7 @@ impl ReadableStream {
         source: ExternalUnderlyingSource,
     ) -> DomRoot<ReadableStream> {
         let _ar = enter_realm(global);
+        let _ais = AutoIncumbentScript::new(global);
         let cx = global.get_cx();
 
         let source = Rc::new(ExternalUnderlyingSourceController::new(source));