feat: Deno namespace configurable and unfrozen (#11062)

Closes #11033

3 files changed, 16 insertions, 45 deletions

diff --git a/cli/tests/unit/globals_test.ts b/cli/tests/unit/globals_test.ts
index 7603457b9..08ae23765 100644
--- a/cli/tests/unit/globals_test.ts
+++ b/cli/tests/unit/globals_test.ts
@@ -62,8 +62,8 @@ unitTest(function DenoNamespaceEqualsWindowDeno(): void {
   assert(Deno === window.Deno);
 });
 
-unitTest(function DenoNamespaceIsFrozen(): void {
-  assert(Object.isFrozen(Deno));
+unitTest(function DenoNamespaceIsNotFrozen(): void {
+  assert(!Object.isFrozen(Deno));
 });
 
 unitTest(function webAssemblyExists(): void {
@@ -77,46 +77,14 @@ declare global {
   }
 }
 
-unitTest(function DenoNamespaceImmutable(): void {
-  const denoCopy = window.Deno;
-  try {
-    // deno-lint-ignore no-explicit-any
-    (Deno as any) = 1;
-  } catch {
-    // pass
-  }
-  assert(denoCopy === Deno);
-  try {
-    // deno-lint-ignore no-explicit-any
-    (window as any).Deno = 1;
-  } catch {
-    // pass
-  }
-  assert(denoCopy === Deno);
-  try {
-    // deno-lint-ignore no-explicit-any
-    delete (window as any).Deno;
-  } catch {
-    // pass
-  }
-  assert(denoCopy === Deno);
-
-  const { readFile } = Deno;
-  try {
-    // deno-lint-ignore no-explicit-any
-    (Deno as any).readFile = 1;
-  } catch {
-    // pass
-  }
-  assert(readFile === Deno.readFile);
-  try {
-    // deno-lint-ignore no-explicit-any
-    delete (window as any).Deno.readFile;
-  } catch {
-    // pass
-  }
-  assert(readFile === Deno.readFile);
+unitTest(function DenoNamespaceConfigurable() {
+  const desc = Object.getOwnPropertyDescriptor(globalThis, "Deno");
+  assert(desc);
+  assert(desc.configurable);
+  assert(!desc.writable);
+});
 
+unitTest(function DenoCoreNamespaceIsImmutable(): void {
   const { print } = Deno.core;
   try {
     Deno.core.print = 1;
diff --git a/runtime/js/06_util.js b/runtime/js/06_util.js
index 9df9ac88a..3809cc9d0 100644
--- a/runtime/js/06_util.js
+++ b/runtime/js/06_util.js
@@ -117,6 +117,7 @@
     return {
       value,
       writable: true,
+      enumerable: false,
       configurable: true,
     };
   }
@@ -125,6 +126,8 @@
     return {
       value,
       enumerable: true,
+      writable: false,
+      configurable: true,
     };
   }
 
@@ -132,6 +135,7 @@
     return {
       get: getter,
       enumerable: true,
+      configurable: true,
     };
   }
 
diff --git a/runtime/js/99_main.js b/runtime/js/99_main.js
index 09a2ebb55..91a4dcefd 100644
--- a/runtime/js/99_main.js
+++ b/runtime/js/99_main.js
@@ -492,10 +492,9 @@ delete Object.prototype.__proto__;
       Object.assign(finalDenoNs, denoNsUnstable);
     }
 
-    // Setup `Deno` global - we're actually overriding already
-    // existing global `Deno` with `Deno` namespace from "./deno.ts".
-    util.immutableDefine(globalThis, "Deno", finalDenoNs);
-    Object.freeze(globalThis.Deno);
+    // Setup `Deno` global - we're actually overriding already existing global
+    // `Deno` with `Deno` namespace from "./deno.ts".
+    Object.defineProperty(globalThis, "Deno", util.readOnly(finalDenoNs));
     Object.freeze(globalThis.Deno.core);
     Object.freeze(globalThis.Deno.core.sharedQueue);
     signals.setSignals();