buffer: fix cancel()

* fix mismatch between return value & read value that would either crash
  or freeze the browser depending on its mood
* add an assertion to detect the above footgun
* fix some resource leaks
* fix iteration over a table that called a function which altered the
  table in buffer's cancel()
* if user cancels before anything is loaded, destroy the container too

1 files changed, 1 insertions, 0 deletions

diff --git a/src/loader/loader.nim b/src/loader/loader.nim
index 5aed021e..295062b5 100644
--- a/src/loader/loader.nim
+++ b/src/loader/loader.nim
@@ -987,6 +987,7 @@ proc onConnected*(loader: FileLoader, fd: int) =
     r.sread(msg) # packet 1
     loader.unregisterFun(fd)
     loader.unregistered.add(fd)
+    stream.sclose()
     let err = newTypeError("NetworkError when attempting to fetch resource")
     promise.resolve(JSResult[Response].err(err))
   loader.connecting.del(fd)