feat(ext/node): properly segregate node globals (#19307)

Code run within Deno-mode and Node-mode should have access to a
slightly different set of globals. Previously this was done through a
compile time code-transform for Node-mode, but this is not ideal and has
many edge cases, for example Node's globalThis having a different
identity than Deno's globalThis.

This commit makes the `globalThis` of the entire runtime a semi-proxy.
This proxy returns a different set of globals depending on the caller's
mode. This is not a full proxy, because it is shadowed by "real"
properties on globalThis. This is done to avoid the overhead of a full
proxy for all globalThis operations.

The globals between Deno-mode and Node-mode are now properly segregated.
This means that code running in Deno-mode will not have access to Node's
globals, and vice versa. Deleting a managed global in Deno-mode will
NOT delete the corresponding global in Node-mode, and vice versa.

---------

Co-authored-by: Bartek Iwańczuk <biwanczuk@gmail.com>
Co-authored-by: Aapo Alasuutari <aapo.alasuutari@gmail.com>

1 files changed, 5 insertions, 3 deletions

diff --git a/runtime/js/99_main.js b/runtime/js/99_main.js
index 0c8989701..483ca9012 100644
--- a/runtime/js/99_main.js
+++ b/runtime/js/99_main.js
@@ -413,14 +413,16 @@ function promiseRejectMacrotaskCallback() {
 }
 
 let hasBootstrapped = false;
+// Delete the `console` object that V8 automaticaly adds onto the global wrapper
+// object on context creation. We don't want this console object to shadow the
+// `console` object exposed by the ext/node globalThis proxy.
+delete globalThis.console;
 // Set up global properties shared by main and worker runtime.
 ObjectDefineProperties(globalThis, windowOrWorkerGlobalScope);
 // FIXME(bartlomieju): temporarily add whole `Deno.core` to
 // `Deno[Deno.internal]` namespace. It should be removed and only necessary
 // methods should be left there.
-ObjectAssign(internals, {
-  core,
-});
+ObjectAssign(internals, { core });
 const internalSymbol = Symbol("Deno.internal");
 const finalDenoNs = {
   internal: internalSymbol,