fix: dynamic import panic (#2792)

core/isolate.rs

@@ -440,10 +440,7 @@ impl Isolate {
       libdeno::deno_mod_new(self.libdeno_isolate, main, name_ptr, source_ptr)
     };
 
-    self.check_last_exception().map(|_| id).map_err(|err| {
-      assert_eq!(id, 0);
-      err
-    })
+    self.check_last_exception().map(|_| id)
   }
 
   pub fn mod_get_imports(&self, id: deno_mod) -> Vec<String> {
@@ -503,10 +500,7 @@ impl Isolate {
         err_str_ptr,
       )
     };
-    self.check_last_exception().map_err(|err| {
-      assert_eq!(id, 0);
-      err
-    })
+    self.check_last_exception()
   }
 
   fn poll_dyn_imports(&mut self) -> Poll<(), ErrBox> {
@@ -1012,6 +1006,60 @@ pub mod tests {
     })
   }
 
+  #[test]
+  fn dyn_import_err2() {
+    use std::convert::TryInto;
+    // Import multiple modules to demonstrate that after failed dynamic import
+    // another dynamic import can still be run
+    run_in_task(|| {
+      let count = Arc::new(AtomicUsize::new(0));
+      let count_ = count.clone();
+      let mut isolate = Isolate::new(StartupData::None, false);
+      isolate.set_dyn_import(move |_, specifier, referrer| {
+        let c = count_.fetch_add(1, Ordering::Relaxed);
+        match c {
+          0 => assert_eq!(specifier, "foo1.js"),
+          1 => assert_eq!(specifier, "foo2.js"),
+          2 => assert_eq!(specifier, "foo3.js"),
+          _ => unreachable!(),
+        }
+        assert_eq!(referrer, "dyn_import_error.js");
+
+        let source_code_info = SourceCodeInfo {
+          module_url_specified: specifier.to_owned(),
+          module_url_found: specifier.to_owned(),
+          code: "# not valid JS".to_owned(),
+        };
+        let stream = MockImportStream(vec![
+          Ok(RecursiveLoadEvent::Fetch(source_code_info)),
+          Ok(RecursiveLoadEvent::Instantiate(c.try_into().unwrap())),
+        ]);
+        Box::new(stream)
+      });
+
+      js_check(isolate.execute(
+        "dyn_import_error.js",
+        r#"
+        (async () => {
+          await import("foo1.js");
+        })();
+        (async () => {
+          await import("foo2.js");
+        })();
+        (async () => {
+          await import("foo3.js");
+        })();
+        "#,
+      ));
+
+      assert_eq!(count.load(Ordering::Relaxed), 3);
+      // Now each poll should return error
+      assert!(isolate.poll().is_err());
+      assert!(isolate.poll().is_err());
+      assert!(isolate.poll().is_err());
+    })
+  }
+
   #[test]
   fn dyn_import_ok() {
     run_in_task(|| {