Handle uncaught worker errors without panicking (#3019)

cli/deno_error.rs

@@ -22,6 +22,17 @@ pub struct DenoError {
   msg: String,
 }
 
+pub fn print_err_and_exit(err: ErrBox) {
+  eprintln!("{}", err.to_string());
+  std::process::exit(1);
+}
+
+pub fn js_check(r: Result<(), ErrBox>) {
+  if let Err(err) = r {
+    print_err_and_exit(err);
+  }
+}
+
 impl DenoError {
   pub fn new(kind: ErrorKind, msg: String) -> Self {
     Self { kind, msg }

cli/lib.rs

@@ -51,6 +51,8 @@ mod tokio_write;
 pub mod version;
 pub mod worker;
 
+use crate::deno_error::js_check;
+use crate::deno_error::print_err_and_exit;
 use crate::progress::Progress;
 use crate::state::ThreadSafeState;
 use crate::worker::Worker;
@@ -90,17 +92,6 @@ impl log::Log for Logger {
   fn flush(&self) {}
 }
 
-fn print_err_and_exit(err: ErrBox) {
-  eprintln!("{}", err.to_string());
-  std::process::exit(1);
-}
-
-fn js_check(r: Result<(), ErrBox>) {
-  if let Err(err) = r {
-    print_err_and_exit(err);
-  }
-}
-
 fn create_worker_and_state(
   flags: DenoFlags,
   argv: Vec<String>,
@@ -118,7 +109,7 @@ fn create_worker_and_state(
   });
   // TODO(kevinkassimo): maybe make include_deno_namespace also configurable?
   let state = ThreadSafeState::new(flags, argv, progress, true)
-    .map_err(print_err_and_exit)
+    .map_err(deno_error::print_err_and_exit)
     .unwrap();
   let worker = Worker::new(
     "main".to_string(),

cli/ops/workers.rs

@@ -1,5 +1,6 @@
 // Copyright 2018-2019 the Deno authors. All rights reserved. MIT license.
 use super::dispatch_json::{Deserialize, JsonOp, Value};
+use crate::deno_error::js_check;
 use crate::deno_error::DenoError;
 use crate::deno_error::ErrorKind;
 use crate::resources;
@@ -124,8 +125,8 @@ pub fn op_create_worker(
 
   let mut worker =
     Worker::new(name, startup_data::deno_isolate_init(), child_state);
-  worker.execute(&deno_main_call).unwrap();
-  worker.execute("workerMain()").unwrap();
+  js_check(worker.execute(&deno_main_call));
+  js_check(worker.execute("workerMain()"));
 
   let exec_cb = move |worker: Worker| {
     let mut workers_tl = parent_state.workers.lock().unwrap();
@@ -135,7 +136,7 @@ pub fn op_create_worker(
 
   // Has provided source code, execute immediately.
   if has_source_code {
-    worker.execute(&source_code).unwrap();
+    js_check(worker.execute(&source_code));
     return Ok(JsonOp::Sync(exec_cb(worker)));
   }
 

cli/tests/error_worker_dynamic.ts

@@ -0,0 +1,3 @@
+const b = new Blob(['throw new Error("hello");']);
+const blobURL = URL.createObjectURL(b);
+new Worker(blobURL);

cli/tests/error_worker_dynamic.ts.out

@@ -0,0 +1,3 @@
+[WILDCARD]error: Uncaught Error: hello
+[WILDCARD]__anonymous__:1:7
+    at [WILDCARD]__anonymous__:1:7

cli/tests/integration_tests.rs

@@ -474,6 +474,13 @@ itest!(error_type_definitions {
   output: "error_type_definitions.ts.out",
 });
 
+itest!(error_worker_dynamic {
+  args: "run --reload error_worker_dynamic.ts",
+  check_stderr: true,
+  exit_code: 1,
+  output: "error_worker_dynamic.ts.out",
+});
+
 itest!(exit_error42 {
   exit_code: 42,
   args: "run --reload exit_error42.ts",