1 files changed, 34 insertions, 0 deletions
diff --git a/cli/args/flags.rs b/cli/args/flags.rs
index 9b0f840e9..5261411ce 100644
--- a/cli/args/flags.rs
+++ b/cli/args/flags.rs
@@ -417,6 +417,7 @@ pub struct Flags {
   pub no_prompt: bool,
   pub reload: bool,
   pub seed: Option<u64>,
+  pub strace_ops: Option<Vec<String>>,
   pub unstable: bool,
   pub unstable_bare_node_builtins: bool,
   pub unstable_byonm: bool,
@@ -2688,6 +2689,7 @@ fn runtime_args(
     .arg(v8_flags_arg())
     .arg(seed_arg())
     .arg(enable_testing_features_arg())
+    .arg(strace_ops_arg())
 }
 
 fn inspect_args(app: Command) -> Command {
@@ -2837,6 +2839,17 @@ fn enable_testing_features_arg() -> Arg {
     .hide(true)
 }
 
+fn strace_ops_arg() -> Arg {
+  Arg::new("strace-ops")
+    .long("strace-ops")
+    .num_args(0..)
+    .use_value_delimiter(true)
+    .require_equals(true)
+    .value_name("OPS")
+    .help("Trace low-level op calls")
+    .hide(true)
+}
+
 fn v8_flags_arg() -> Arg {
   Arg::new("v8-flags")
     .long("v8-flags")
@@ -3802,6 +3815,7 @@ fn permission_args_parse(flags: &mut Flags, matches: &mut ArgMatches) {
     flags.no_prompt = true;
   }
 }
+
 fn unsafely_ignore_certificate_errors_parse(
   flags: &mut Flags,
   matches: &mut ArgMatches,
@@ -3833,6 +3847,7 @@ fn runtime_args_parse(
   seed_arg_parse(flags, matches);
   enable_testing_features_arg_parse(flags, matches);
   env_file_arg_parse(flags, matches);
+  strace_ops_parse(flags, matches);
 }
 
 fn inspect_arg_parse(flags: &mut Flags, matches: &mut ArgMatches) {
@@ -3900,6 +3915,12 @@ fn enable_testing_features_arg_parse(
   }
 }
 
+fn strace_ops_parse(flags: &mut Flags, matches: &mut ArgMatches) {
+  if let Some(patterns) = matches.remove_many::<String>("strace-ops") {
+    flags.strace_ops = Some(patterns.collect());
+  }
+}
+
 fn cached_only_arg_parse(flags: &mut Flags, matches: &mut ArgMatches) {
   if matches.get_flag("cached-only") {
     flags.cached_only = true;
@@ -5401,6 +5422,19 @@ mod tests {
   }
 
   #[test]
+  fn repl_strace_ops() {
+    // Lightly test this undocumented flag
+    let r = flags_from_vec(svec!["deno", "repl", "--strace-ops"]);
+    assert_eq!(r.unwrap().strace_ops, Some(vec![]));
+    let r =
+      flags_from_vec(svec!["deno", "repl", "--strace-ops=http,websocket"]);
+    assert_eq!(
+      r.unwrap().strace_ops,
+      Some(vec!["http".to_string(), "websocket".to_string()])
+    );
+  }
+
+  #[test]
   fn repl_with_flags() {
     #[rustfmt::skip]
     let r = flags_from_vec(svec!["deno", "repl", "-A", "--import-map", "import_map.json", "--no-remote", "--config", "tsconfig.json", "--no-check", "--reload", "--lock", "lock.json", "--lock-write", "--cert", "example.crt", "--cached-only", "--location", "https:foo", "--v8-flags=--help", "--seed", "1", "--inspect=127.0.0.1:9229", "--unsafely-ignore-certificate-errors", "--env=.example.env"]);