3 files changed, 24 insertions, 11 deletions
diff --git a/runtime/js/99_main.js b/runtime/js/99_main.js
index 2ea122e34..fcec6b91a 100644
--- a/runtime/js/99_main.js
+++ b/runtime/js/99_main.js
@@ -8,7 +8,8 @@ import { core, internals, primordials } from "ext:core/mod.js";
 const ops = core.ops;
 import {
   op_bootstrap_args,
-  op_bootstrap_is_tty,
+  op_bootstrap_is_stderr_tty,
+  op_bootstrap_is_stdout_tty,
   op_bootstrap_no_color,
   op_bootstrap_pid,
   op_main_module,
@@ -62,10 +63,10 @@ import * as timers from "ext:deno_web/02_timers.js";
 import {
   customInspect,
   getDefaultInspectOptions,
-  getNoColor,
+  getStderrNoColor,
   inspectArgs,
   quoteString,
-  setNoColorFn,
+  setNoColorFns,
 } from "ext:deno_console/01_console.js";
 import * as performance from "ext:deno_web/15_performance.js";
 import * as url from "ext:deno_url/00_url.js";
@@ -379,7 +380,10 @@ function importScripts(...urls) {
 
 const opArgs = memoizeLazy(() => op_bootstrap_args());
 const opPid = memoizeLazy(() => op_bootstrap_pid());
-setNoColorFn(() => op_bootstrap_no_color() || !op_bootstrap_is_tty());
+setNoColorFns(
+  () => op_bootstrap_no_color() || !op_bootstrap_is_stdout_tty(),
+  () => op_bootstrap_no_color() || !op_bootstrap_is_stderr_tty(),
+);
 
 function formatException(error) {
   if (
@@ -390,11 +394,11 @@ function formatException(error) {
   } else if (typeof error == "string") {
     return `Uncaught ${
       inspectArgs([quoteString(error, getDefaultInspectOptions())], {
-        colors: !getNoColor(),
+        colors: !getStderrNoColor(),
       })
     }`;
   } else {
-    return `Uncaught ${inspectArgs([error], { colors: !getNoColor() })}`;
+    return `Uncaught ${inspectArgs([error], { colors: !getStderrNoColor() })}`;
   }
 }
 
diff --git a/runtime/ops/bootstrap.rs b/runtime/ops/bootstrap.rs
index cbb87db88..eb9dbc6e8 100644
--- a/runtime/ops/bootstrap.rs
+++ b/runtime/ops/bootstrap.rs
@@ -16,7 +16,8 @@ deno_core::extension!(
     op_bootstrap_language,
     op_bootstrap_log_level,
     op_bootstrap_no_color,
-    op_bootstrap_is_tty,
+    op_bootstrap_is_stdout_tty,
+    op_bootstrap_is_stderr_tty,
     op_bootstrap_unstable_args,
     op_snapshot_options,
   ],
@@ -117,7 +118,13 @@ pub fn op_bootstrap_no_color(state: &mut OpState) -> bool {
 }
 
 #[op2(fast)]
-pub fn op_bootstrap_is_tty(state: &mut OpState) -> bool {
+pub fn op_bootstrap_is_stdout_tty(state: &mut OpState) -> bool {
   let options = state.borrow::<BootstrapOptions>();
-  options.is_tty
+  options.is_stdout_tty
+}
+
+#[op2(fast)]
+pub fn op_bootstrap_is_stderr_tty(state: &mut OpState) -> bool {
+  let options = state.borrow::<BootstrapOptions>();
+  options.is_stderr_tty
 }
diff --git a/runtime/worker_bootstrap.rs b/runtime/worker_bootstrap.rs
index 31cb883db..e1abf87fc 100644
--- a/runtime/worker_bootstrap.rs
+++ b/runtime/worker_bootstrap.rs
@@ -76,7 +76,8 @@ pub struct BootstrapOptions {
   pub location: Option<ModuleSpecifier>,
   /// Sets `Deno.noColor` in JS runtime.
   pub no_color: bool,
-  pub is_tty: bool,
+  pub is_stdout_tty: bool,
+  pub is_stderr_tty: bool,
   // --unstable flag, deprecated
   pub unstable: bool,
   // --unstable-* flags
@@ -109,7 +110,8 @@ impl Default for BootstrapOptions {
       user_agent,
       cpu_count,
       no_color: !colors::use_color(),
-      is_tty: deno_terminal::is_stdout_tty(),
+      is_stdout_tty: deno_terminal::is_stdout_tty(),
+      is_stderr_tty: deno_terminal::is_stderr_tty(),
       enable_op_summary_metrics: Default::default(),
       enable_testing_features: Default::default(),
       log_level: Default::default(),