7 files changed, 75 insertions, 19 deletions
diff --git a/ext/node/polyfills/02_init.js b/ext/node/polyfills/02_init.js
index 752f518bf..71eebbc81 100644
--- a/ext/node/polyfills/02_init.js
+++ b/ext/node/polyfills/02_init.js
@@ -29,7 +29,12 @@ function initialize(
 
     // FIXME(bartlomieju): not nice to depend on `Deno` namespace here
     // but it's the only way to get `args` and `version` and this point.
-    internals.__bootstrapNodeProcess(argv0, Deno.args, Deno.version);
+    internals.__bootstrapNodeProcess(
+      argv0,
+      Deno.args,
+      Deno.version,
+      Deno.env.get("NODE_DEBUG") ?? "",
+    );
     internals.__initWorkerThreads(
       runningOnMainThread,
       workerId,
@@ -40,7 +45,13 @@ function initialize(
     delete internals.requireImpl;
   } else {
     // Warm up the process module
-    internals.__bootstrapNodeProcess(undefined, undefined, undefined, true);
+    internals.__bootstrapNodeProcess(
+      undefined,
+      undefined,
+      undefined,
+      undefined,
+      true,
+    );
   }
 }
 
diff --git a/ext/node/polyfills/internal/util/debuglog.ts b/ext/node/polyfills/internal/util/debuglog.ts
index 3cbcf2c5c..9bbaed606 100644
--- a/ext/node/polyfills/internal/util/debuglog.ts
+++ b/ext/node/polyfills/internal/util/debuglog.ts
@@ -12,7 +12,7 @@ let debugImpls: Record<string, (...args: unknown[]) => void>;
 let testEnabled: (str: string) => boolean;
 
 // `debugEnv` is initial value of process.env.NODE_DEBUG
-function initializeDebugEnv(debugEnv: string) {
+export function initializeDebugEnv(debugEnv: string) {
   debugImpls = Object.create(null);
   if (debugEnv) {
     // This is run before any user code, it's OK not to use primordials.
@@ -106,20 +106,4 @@ export function debuglog(
   return logger;
 }
 
-let debugEnv;
-/* TODO(kt3k): enable initializing debugEnv.
-It's not possible to access env var when snapshotting.
-
-try {
-  debugEnv = Deno.env.get("NODE_DEBUG") ?? "";
-} catch (error) {
-  if (error instanceof Deno.errors.PermissionDenied) {
-    debugEnv = "";
-  } else {
-    throw error;
-  }
-}
-*/
-initializeDebugEnv(debugEnv);
-
 export default { debuglog };
diff --git a/ext/node/polyfills/process.ts b/ext/node/polyfills/process.ts
index 7f522386c..b24bf6a8e 100644
--- a/ext/node/polyfills/process.ts
+++ b/ext/node/polyfills/process.ts
@@ -5,6 +5,7 @@
 // deno-lint-ignore-file prefer-primordials
 
 import { core, internals } from "ext:core/mod.js";
+import { initializeDebugEnv } from "ext:deno_node/internal/util/debuglog.ts";
 import {
   op_geteuid,
   op_node_process_kill,
@@ -845,6 +846,7 @@ internals.__bootstrapNodeProcess = function (
   argv0Val: string | undefined,
   args: string[],
   denoVersions: Record<string, string>,
+  nodeDebug: string,
   warmup = false,
 ) {
   if (!warmup) {
@@ -891,6 +893,8 @@ internals.__bootstrapNodeProcess = function (
     platform = isWindows ? "win32" : Deno.build.os;
     pid = Deno.pid;
 
+    initializeDebugEnv(nodeDebug);
+
     // @ts-ignore Remove setStartTime and #startTime is not modifiable
     delete process.setStartTime;
     delete internals.__bootstrapNodeProcess;
diff --git a/tests/specs/node/node_debug/__test__.jsonc b/tests/specs/node/node_debug/__test__.jsonc
new file mode 100644
index 000000000..825d3bd3f
--- /dev/null
+++ b/tests/specs/node/node_debug/__test__.jsonc
@@ -0,0 +1,6 @@
+{
+  "args": "run --allow-read main.mjs",
+  "envs": { "NODE_DEBUG": "*" },
+  "output": "main.out",
+  "exitCode": 0
+}
diff --git a/tests/specs/node/node_debug/hello.txt b/tests/specs/node/node_debug/hello.txt
new file mode 100644
index 000000000..3b18e512d
--- /dev/null
+++ b/tests/specs/node/node_debug/hello.txt
@@ -0,0 +1 @@
+hello world
diff --git a/tests/specs/node/node_debug/main.mjs b/tests/specs/node/node_debug/main.mjs
new file mode 100644
index 000000000..b33657982
--- /dev/null
+++ b/tests/specs/node/node_debug/main.mjs
@@ -0,0 +1,14 @@
+import { createReadStream } from "node:fs";
+import path from "node:path";
+
+const filePath = path.join(import.meta.dirname, "hello.txt");
+const readableStream = createReadStream(filePath);
+readableStream.on("data", (chunk) => {
+  console.log(chunk.toString());
+});
+readableStream.on("end", () => {
+  console.log("Finished reading the file");
+});
+readableStream.on("error", (error) => {
+  console.error("Error reading the file:", error);
+});
diff --git a/tests/specs/node/node_debug/main.out b/tests/specs/node/node_debug/main.out
new file mode 100644
index 000000000..efdd4c209
--- /dev/null
+++ b/tests/specs/node/node_debug/main.out
@@ -0,0 +1,36 @@
+STREAM [WILDCARD] 'resume'
+STREAM [WILDCARD] 'resume' false
+STREAM [WILDCARD] 'read' 0
+STREAM [WILDCARD] 'need readable' false
+STREAM [WILDCARD] 'length less than watermark' true
+STREAM [WILDCARD] 'reading, ended or constructing' false
+STREAM [WILDCARD] 'flow' true
+STREAM [WILDCARD] 'read' undefined
+STREAM [WILDCARD] 'need readable' true
+STREAM [WILDCARD] 'length less than watermark' true
+STREAM [WILDCARD] 'reading, ended or constructing' false
+STREAM [WILDCARD] 'read' 0
+STREAM [WILDCARD] 'need readable' true
+STREAM [WILDCARD] 'length less than watermark' true
+STREAM [WILDCARD] 'reading, ended or constructing' false
+STREAM [WILDCARD] 'maybeReadMore read 0'
+STREAM [WILDCARD] 'read' 0
+STREAM [WILDCARD] 'need readable' true
+STREAM [WILDCARD] 'length less than watermark' true
+STREAM [WILDCARD] 'do read'
+STREAM [WILDCARD] 'readableAddChunk' <Buffer 68 65 6c 6c 6f 20 77 6f 72 6c 64 0a>
+hello world
+
+STREAM [WILDCARD] 'maybeReadMore read 0'
+STREAM [WILDCARD] 'read' 0
+STREAM [WILDCARD] 'need readable' true
+STREAM [WILDCARD] 'length less than watermark' true
+STREAM [WILDCARD] 'do read'
+STREAM [WILDCARD] 'readableAddChunk' null
+STREAM [WILDCARD] 'onEofChunk'
+STREAM [WILDCARD] 'emitReadable_' false 0 true
+STREAM [WILDCARD] 'flow' true
+STREAM [WILDCARD] 'read' undefined
+STREAM [WILDCARD] 'endReadable' false
+STREAM [WILDCARD] 'endReadableNT' false 0
+Finished reading the file