[bun.js] Add `ShadowRealm`

7 files changed, 70 insertions, 18 deletions

diff --git a/integration/bunjs-only-snippets/fetch.js b/integration/bunjs-only-snippets/fetch.js
deleted file mode 100644
index bb4345659..000000000
--- a/integration/bunjs-only-snippets/fetch.js
+++ /dev/null
@@ -1,17 +0,0 @@
-import fs from "fs";
-
-const urls = ["https://example.com", "http://example.com"];
-for (let url of urls) {
-  const response = await fetch(url);
-  const text = await response.text();
-
-  if (
-    fs.readFileSync(
-      import.meta.path.substring(0, import.meta.path.lastIndexOf("/")) +
-        "/fetch.js.txt",
-      "utf8"
-    ) !== text
-  ) {
-    throw new Error("Expected fetch.js.txt to match snapshot");
-  }
-}
diff --git a/integration/bunjs-only-snippets/fetch.test.js b/integration/bunjs-only-snippets/fetch.test.js
new file mode 100644
index 000000000..72b80cd35
--- /dev/null
+++ b/integration/bunjs-only-snippets/fetch.test.js
@@ -0,0 +1,22 @@
+import { it, describe } from "bun:test";
+import fs from "fs";
+
+describe("fetch", () => {
+  const urls = ["https://example.com", "http://example.com"];
+  for (let url of urls) {
+    it(url, async () => {
+      const response = await fetch(url);
+      const text = await response.text();
+
+      if (
+        fs.readFileSync(
+          import.meta.path.substring(0, import.meta.path.lastIndexOf("/")) +
+            "/fetch.js.txt",
+          "utf8"
+        ) !== text
+      ) {
+        throw new Error("Expected fetch.js.txt to match snapshot");
+      }
+    });
+  }
+});
diff --git a/integration/bunjs-only-snippets/shadow.test.js b/integration/bunjs-only-snippets/shadow.test.js
new file mode 100644
index 000000000..3fffcac90
--- /dev/null
+++ b/integration/bunjs-only-snippets/shadow.test.js
@@ -0,0 +1,10 @@
+import { describe, it, expect } from "bun:test";
+
+it("shadow realm works", () => {
+  const red = new ShadowRealm();
+  globalThis.someValue = 1;
+  // Affects only the ShadowRealm's global
+  const result = red.evaluate("globalThis.someValue = 2;");
+  expect(globalThis.someValue).toBe(1);
+  expect(result).toBe(2);
+});
diff --git a/integration/bunjs-only-snippets/text-encoder.test.js b/integration/bunjs-only-snippets/text-encoder.test.js
index 3b0c1f971..e4bf35059 100644
--- a/integration/bunjs-only-snippets/text-encoder.test.js
+++ b/integration/bunjs-only-snippets/text-encoder.test.js
@@ -69,6 +69,15 @@ describe("TextEncoder", () => {
     }
   });
 
+  it("should encode long latin1 text", () => {
+    const text = "Hello World!".repeat(1000);
+    const encoder = new TextEncoder();
+    const encoded = encoder.encode(text);
+    expect(encoded instanceof Uint8Array).toBe(true);
+    expect(encoded.length).toBe(text.length);
+    expect(new TextDecoder().decode(encoded)).toBe(text);
+  });
+
   it("should encode latin1 rope text", () => {
     var text = "Hello";
     text += " ";
diff --git a/src/javascript/jsc/bindings/ZigGlobalObject.cpp b/src/javascript/jsc/bindings/ZigGlobalObject.cpp
index 3ab654dda..352669b1d 100644
--- a/src/javascript/jsc/bindings/ZigGlobalObject.cpp
+++ b/src/javascript/jsc/bindings/ZigGlobalObject.cpp
@@ -229,6 +229,25 @@ namespace Zig {
 const JSC::ClassInfo GlobalObject::s_info = { "GlobalObject", &Base::s_info, nullptr, nullptr,
     CREATE_METHOD_TABLE(GlobalObject) };
 
+extern "C" JSClassRef* Zig__getAPIGlobals(size_t* count);
+
+static JSGlobalObject* deriveShadowRealmGlobalObject(JSGlobalObject* globalObject)
+{
+    auto& vm = globalObject->vm();
+    Zig::GlobalObject* shadow = Zig::GlobalObject::create(vm, Zig::GlobalObject::createStructure(vm, JSC::jsNull()));
+    shadow->setConsole(shadow);
+    size_t count = 0;
+    JSClassRef* globalObjectClass;
+    globalObjectClass = Zig__getAPIGlobals(&count);
+
+    shadow->setConsole(shadow);
+    if (count > 0) {
+        shadow->installAPIGlobals(globalObjectClass, count);
+    }
+
+    return shadow;
+}
+
 const JSC::GlobalObjectMethodTable GlobalObject::s_globalObjectMethodTable = {
     &supportsRichSourceInfo,
     &shouldInterruptScript,
@@ -247,6 +266,8 @@ const JSC::GlobalObjectMethodTable GlobalObject::s_globalObjectMethodTable = {
     nullptr, // defaultLanguage
     nullptr, // compileStreaming
     nullptr, // instantiateStreaming
+    nullptr,
+    &Zig::deriveShadowRealmGlobalObject
 };
 
 void GlobalObject::reportUncaughtExceptionAtEventLoop(JSGlobalObject* globalObject,
diff --git a/src/javascript/jsc/bindings/ZigGlobalObject.h b/src/javascript/jsc/bindings/ZigGlobalObject.h
index edc250ecb..e2464b99e 100644
--- a/src/javascript/jsc/bindings/ZigGlobalObject.h
+++ b/src/javascript/jsc/bindings/ZigGlobalObject.h
@@ -48,7 +48,7 @@ public:
     }
 
     static void reportUncaughtExceptionAtEventLoop(JSGlobalObject*, JSC::Exception*);
-
+    static JSGlobalObject* deriveShadowRealmGlobalObject(JSGlobalObject* globalObject);
     static void queueMicrotaskToEventLoop(JSC::JSGlobalObject& global, Ref<JSC::Microtask>&& task);
     static JSC::JSInternalPromise* moduleLoaderImportModule(JSGlobalObject*, JSC::JSModuleLoader*,
         JSC::JSString* moduleNameValue,
diff --git a/src/javascript/jsc/bindings/exports.zig b/src/javascript/jsc/bindings/exports.zig
index 6179ad203..a7d281299 100644
--- a/src/javascript/jsc/bindings/exports.zig
+++ b/src/javascript/jsc/bindings/exports.zig
@@ -241,6 +241,12 @@ export fn ZigString__free_global(ptr: [*]const u8, len: usize) void {
     default_allocator.free(str);
 }
 
+export fn Zig__getAPIGlobals(count: *usize) [*]JSC.C.JSClassRef {
+    var globals = JSC.VirtualMachine.getAPIGlobals();
+    count.* = globals.len;
+    return globals.ptr;
+}
+
 pub const JSErrorCode = enum(u8) {
     Error = 0,
     EvalError = 1,
@@ -1855,6 +1861,7 @@ comptime {
     if (!is_bindgen) {
         _ = Process.getTitle;
         _ = Process.setTitle;
+        _ = Zig__getAPIGlobals;
         std.testing.refAllDecls(NodeReadableStream);
         std.testing.refAllDecls(Bun.Timer);
         std.testing.refAllDecls(NodeWritableStream);