runtime: implement CompressionStream/DecompressionStream (#24757)

Closes https://github.com/oven-sh/bun/issues/1723
Closes https://github.com/oven-sh/bun/pull/22214
Closes https://github.com/oven-sh/bun/pull/24241

also supports the `"brotli"` and `"zstd"` formats

<img width="1244" height="547" alt="image"
src="https://github.com/user-attachments/assets/aecf4489-29ad-411d-9f6b-3bee50ed1b27"
/>

bench/runner.mjs

@@ -13,7 +13,4 @@ export function run(opts = {}) {
 }
 
 export const bench = Mitata.bench;
-
-export function group(_name, fn) {
-  return Mitata.group(fn);
-}
+export const group = Mitata.group;

bench/snippets/compression-streams.mjs

@@ -0,0 +1,156 @@
+import { bench, group, run } from "../runner.mjs";
+
+const runAll = !process.argv.includes("--simple");
+
+const small = new Uint8Array(1024);
+const medium = new Uint8Array(1024 * 100);
+const large = new Uint8Array(1024 * 1024);
+
+for (let i = 0; i < large.length; i++) {
+  const value = Math.floor(Math.sin(i / 100) * 128 + 128);
+  if (i < small.length) small[i] = value;
+  if (i < medium.length) medium[i] = value;
+  large[i] = value;
+}
+
+const format = new Intl.NumberFormat("en-US", { notation: "compact", unit: "byte" });
+
+async function compress(data, format) {
+  const cs = new CompressionStream(format);
+  const writer = cs.writable.getWriter();
+  const reader = cs.readable.getReader();
+
+  writer.write(data);
+  writer.close();
+
+  const chunks = [];
+  while (true) {
+    const { done, value } = await reader.read();
+    if (done) break;
+    chunks.push(value);
+  }
+
+  const result = new Uint8Array(chunks.reduce((acc, chunk) => acc + chunk.length, 0));
+  let offset = 0;
+  for (const chunk of chunks) {
+    result.set(chunk, offset);
+    offset += chunk.length;
+  }
+  return result;
+}
+
+async function decompress(data, format) {
+  const ds = new DecompressionStream(format);
+  const writer = ds.writable.getWriter();
+  const reader = ds.readable.getReader();
+
+  writer.write(data);
+  writer.close();
+
+  const chunks = [];
+  while (true) {
+    const { done, value } = await reader.read();
+    if (done) break;
+    chunks.push(value);
+  }
+
+  const result = new Uint8Array(chunks.reduce((acc, chunk) => acc + chunk.length, 0));
+  let offset = 0;
+  for (const chunk of chunks) {
+    result.set(chunk, offset);
+    offset += chunk.length;
+  }
+  return result;
+}
+
+async function roundTrip(data, format) {
+  const compressed = await compress(data, format);
+  return await decompress(compressed, format);
+}
+
+const formats = ["deflate", "gzip", "deflate-raw"];
+if (runAll) formats.push("brotli", "zstd");
+
+// Small data benchmarks (1KB)
+group(`CompressionStream ${format.format(small.length)}`, () => {
+  for (const fmt of formats) {
+    try {
+      new CompressionStream(fmt);
+      bench(fmt, async () => await compress(small, fmt));
+    } catch (e) {
+      // Skip unsupported formats
+    }
+  }
+});
+
+// Medium data benchmarks (100KB)
+group(`CompressionStream ${format.format(medium.length)}`, () => {
+  for (const fmt of formats) {
+    try {
+      new CompressionStream(fmt);
+      bench(fmt, async () => await compress(medium, fmt));
+    } catch (e) {}
+  }
+});
+
+// Large data benchmarks (1MB)
+group(`CompressionStream ${format.format(large.length)}`, () => {
+  for (const fmt of formats) {
+    try {
+      new CompressionStream(fmt);
+      bench(fmt, async () => await compress(large, fmt));
+    } catch (e) {
+      // Skip unsupported formats
+    }
+  }
+});
+
+const compressedData = {};
+for (const fmt of formats) {
+  try {
+    compressedData[fmt] = {
+      small: await compress(small, fmt),
+      medium: await compress(medium, fmt),
+      large: await compress(large, fmt),
+    };
+  } catch (e) {
+    // Skip unsupported formats
+  }
+}
+
+group(`DecompressionStream ${format.format(small.length)}`, () => {
+  for (const fmt of formats) {
+    if (compressedData[fmt]) {
+      bench(fmt, async () => await decompress(compressedData[fmt].small, fmt));
+    }
+  }
+});
+
+group(`DecompressionStream ${format.format(medium.length)}`, () => {
+  for (const fmt of formats) {
+    if (compressedData[fmt]) {
+      bench(fmt, async () => await decompress(compressedData[fmt].medium, fmt));
+    }
+  }
+});
+
+group(`DecompressionStream ${format.format(large.length)}`, () => {
+  for (const fmt of formats) {
+    if (compressedData[fmt]) {
+      bench(fmt, async () => await decompress(compressedData[fmt].large, fmt));
+    }
+  }
+});
+
+group(`roundtrip ${format.format(large.length)}`, () => {
+  for (const fmt of formats) {
+    try {
+      new CompressionStream(fmt);
+      bench(fmt, async () => await roundTrip(large, fmt));
+    } catch (e) {
+      // Skip unsupported formats
+    }
+  }
+});
+
+await run();

docs/runtime/nodejs-compat.mdx

@@ -245,7 +245,7 @@ The table below lists all globals implemented by Node.js and Bun's current compa
 
 ### [`CompressionStream`](https://developer.mozilla.org/en-US/docs/Web/API/CompressionStream)
 
-🔴 Not implemented.
+🟢 Fully implemented.
 
 ### [`console`](https://developer.mozilla.org/en-US/docs/Web/API/console)
 
@@ -273,7 +273,7 @@ The table below lists all globals implemented by Node.js and Bun's current compa
 
 ### [`DecompressionStream`](https://developer.mozilla.org/en-US/docs/Web/API/DecompressionStream)
 
-🔴 Not implemented.
+🟢 Fully implemented.
 
 ### [`Event`](https://developer.mozilla.org/en-US/docs/Web/API/Event)
 

src/bun.js/bindings/JSCompressionStream.cpp

@@ -0,0 +1,139 @@
+#include "config.h"
+#include "JSCompressionStream.h"
+
+#include "JSDOMBuiltinConstructor.h"
+#include "JSDOMGlobalObjectInlines.h"
+#include "WebCoreJSClientData.h"
+#include "WebCoreJSBuiltins.h"
+#include <JavaScriptCore/FunctionPrototype.h>
+#include <JavaScriptCore/JSCInlines.h>
+
+namespace WebCore {
+
+using namespace JSC;
+
+static JSC_DECLARE_CUSTOM_GETTER(jsCompressionStreamConstructor);
+
+class JSCompressionStreamPrototype final : public JSC::JSNonFinalObject {
+public:
+    using Base = JSC::JSNonFinalObject;
+    static JSCompressionStreamPrototype* create(JSC::VM& vm, JSDOMGlobalObject* globalObject, JSC::Structure* structure)
+    {
+        JSCompressionStreamPrototype* ptr = new (NotNull, JSC::allocateCell<JSCompressionStreamPrototype>(vm)) JSCompressionStreamPrototype(vm, globalObject, structure);
+        ptr->finishCreation(vm);
+        return ptr;
+    }
+
+    DECLARE_INFO;
+    template<typename CellType, JSC::SubspaceAccess>
+    static JSC::GCClient::IsoSubspace* subspaceFor(JSC::VM& vm)
+    {
+        STATIC_ASSERT_ISO_SUBSPACE_SHARABLE(JSCompressionStreamPrototype, Base);
+        return &vm.plainObjectSpace();
+    }
+
+    static JSC::Structure* createStructure(JSC::VM& vm, JSC::JSGlobalObject* globalObject, JSC::JSValue prototype)
+    {
+        return JSC::Structure::create(vm, globalObject, prototype, JSC::TypeInfo(JSC::ObjectType, StructureFlags), info());
+    }
+
+private:
+    JSCompressionStreamPrototype(JSC::VM& vm, JSC::JSGlobalObject*, JSC::Structure* structure)
+        : JSC::JSNonFinalObject(vm, structure)
+    {
+    }
+
+    void finishCreation(JSC::VM&);
+};
+STATIC_ASSERT_ISO_SUBSPACE_SHARABLE(JSCompressionStreamPrototype, JSCompressionStreamPrototype::Base);
+
+using JSCompressionStreamDOMConstructor = JSDOMBuiltinConstructor<JSCompressionStream>;
+
+template<> const ClassInfo JSCompressionStreamDOMConstructor::s_info = { "CompressionStream"_s, &Base::s_info, nullptr, nullptr, CREATE_METHOD_TABLE(JSCompressionStreamDOMConstructor) };
+
+template<> JSValue JSCompressionStreamDOMConstructor::prototypeForStructure(JSC::VM& vm, const JSDOMGlobalObject& globalObject)
+{
+    UNUSED_PARAM(vm);
+    return globalObject.functionPrototype();
+}
+
+template<> void JSCompressionStreamDOMConstructor::initializeProperties(VM& vm, JSDOMGlobalObject& globalObject)
+{
+    putDirect(vm, vm.propertyNames->length, jsNumber(0), JSC::PropertyAttribute::ReadOnly | JSC::PropertyAttribute::DontEnum);
+    JSString* nameString = jsNontrivialString(vm, "CompressionStream"_s);
+    m_originalName.set(vm, this, nameString);
+    putDirect(vm, vm.propertyNames->name, nameString, JSC::PropertyAttribute::ReadOnly | JSC::PropertyAttribute::DontEnum);
+    putDirect(vm, vm.propertyNames->prototype, JSCompressionStream::prototype(vm, globalObject), JSC::PropertyAttribute::ReadOnly | JSC::PropertyAttribute::DontEnum | JSC::PropertyAttribute::DontDelete);
+}
+
+template<> FunctionExecutable* JSCompressionStreamDOMConstructor::initializeExecutable(VM& vm)
+{
+    return compressionStreamInitializeCompressionStreamCodeGenerator(vm);
+}
+
+static const HashTableValue JSCompressionStreamPrototypeTableValues[] = {
+    { "constructor"_s, static_cast<unsigned>(JSC::PropertyAttribute::DontEnum), NoIntrinsic, { HashTableValue::GetterSetterType, jsCompressionStreamConstructor, 0 } },
+    { "readable"_s, static_cast<unsigned>(JSC::PropertyAttribute::DontEnum | JSC::PropertyAttribute::ReadOnly | JSC::PropertyAttribute::Accessor | JSC::PropertyAttribute::Builtin), NoIntrinsic, { HashTableValue::BuiltinAccessorType, compressionStreamReadableCodeGenerator, 0 } },
+    { "writable"_s, static_cast<unsigned>(JSC::PropertyAttribute::DontEnum | JSC::PropertyAttribute::ReadOnly | JSC::PropertyAttribute::Accessor | JSC::PropertyAttribute::Builtin), NoIntrinsic, { HashTableValue::BuiltinAccessorType, compressionStreamWritableCodeGenerator, 0 } },
+};
+
+const ClassInfo JSCompressionStreamPrototype::s_info = { "CompressionStream"_s, &Base::s_info, nullptr, nullptr, CREATE_METHOD_TABLE(JSCompressionStreamPrototype) };
+
+void JSCompressionStreamPrototype::finishCreation(VM& vm)
+{
+    Base::finishCreation(vm);
+    reifyStaticProperties(vm, JSCompressionStream::info(), JSCompressionStreamPrototypeTableValues, *this);
+    JSC_TO_STRING_TAG_WITHOUT_TRANSITION();
+}
+
+const ClassInfo JSCompressionStream::s_info = { "CompressionStream"_s, &Base::s_info, nullptr, nullptr, CREATE_METHOD_TABLE(JSCompressionStream) };
+
+JSC::GCClient::IsoSubspace* JSCompressionStream::subspaceForImpl(JSC::VM& vm)
+{
+    return WebCore::subspaceForImpl<JSCompressionStream, UseCustomHeapCellType::No>(
+        vm,
+        [](auto& spaces) { return spaces.m_clientSubspaceForCompressionStream.get(); },
+        [](auto& spaces, auto&& space) { spaces.m_clientSubspaceForCompressionStream = std::forward<decltype(space)>(space); },
+        [](auto& spaces) { return spaces.m_subspaceForCompressionStream.get(); },
+        [](auto& spaces, auto&& space) { spaces.m_subspaceForCompressionStream = std::forward<decltype(space)>(space); });
+}
+
+JSCompressionStream::JSCompressionStream(Structure* structure, JSDOMGlobalObject& globalObject)
+    : JSDOMObject(structure, globalObject)
+{
+}
+
+void JSCompressionStream::finishCreation(VM& vm)
+{
+    Base::finishCreation(vm);
+    ASSERT(inherits(info()));
+}
+
+JSObject* JSCompressionStream::createPrototype(VM& vm, JSDOMGlobalObject& globalObject)
+{
+    auto* structure = JSCompressionStreamPrototype::createStructure(vm, &globalObject, globalObject.objectPrototype());
+    structure->setMayBePrototype(true);
+    return JSCompressionStreamPrototype::create(vm, &globalObject, structure);
+}
+
+JSObject* JSCompressionStream::prototype(VM& vm, JSDOMGlobalObject& globalObject)
+{
+    return getDOMPrototype<JSCompressionStream>(vm, globalObject);
+}
+
+JSValue JSCompressionStream::getConstructor(VM& vm, const JSGlobalObject* globalObject)
+{
+    return getDOMConstructor<JSCompressionStreamDOMConstructor, DOMConstructorID::CompressionStream>(vm, *jsCast<const JSDOMGlobalObject*>(globalObject));
+}
+
+JSC_DEFINE_CUSTOM_GETTER(jsCompressionStreamConstructor, (JSGlobalObject * lexicalGlobalObject, EncodedJSValue thisValue, PropertyName))
+{
+    auto& vm = JSC::getVM(lexicalGlobalObject);
+    auto throwScope = DECLARE_THROW_SCOPE(vm);
+    auto* prototype = jsDynamicCast<JSCompressionStreamPrototype*>(JSValue::decode(thisValue));
+    if (!prototype)
+        return throwVMTypeError(lexicalGlobalObject, throwScope);
+    return JSValue::encode(JSCompressionStream::getConstructor(vm, lexicalGlobalObject));
+}
+
+} // namespace WebCore

src/bun.js/bindings/JSCompressionStream.h

@@ -0,0 +1,40 @@
+#pragma once
+
+#include "JSDOMWrapper.h"
+
+namespace WebCore {
+
+class JSCompressionStream : public JSDOMObject {
+public:
+    using Base = JSDOMObject;
+    static JSCompressionStream* create(JSC::Structure* structure, JSDOMGlobalObject* globalObject)
+    {
+        JSCompressionStream* ptr = new (NotNull, JSC::allocateCell<JSCompressionStream>(globalObject->vm())) JSCompressionStream(structure, *globalObject);
+        ptr->finishCreation(globalObject->vm());
+        return ptr;
+    }
+
+    static JSC::JSObject* createPrototype(JSC::VM&, JSDOMGlobalObject&);
+    static JSC::JSObject* prototype(JSC::VM&, JSDOMGlobalObject&);
+    static JSC::JSValue getConstructor(JSC::VM&, const JSC::JSGlobalObject*);
+
+    DECLARE_INFO;
+
+    static JSC::Structure* createStructure(JSC::VM& vm, JSC::JSGlobalObject* globalObject, JSC::JSValue prototype)
+    {
+        return JSC::Structure::create(vm, globalObject, prototype, JSC::TypeInfo(JSC::ObjectType, StructureFlags), info());
+    }
+
+    template<typename, JSC::SubspaceAccess mode> static JSC::GCClient::IsoSubspace* subspaceFor(JSC::VM& vm)
+    {
+        if constexpr (mode == JSC::SubspaceAccess::Concurrently)
+            return nullptr;
+        return subspaceForImpl(vm);
+    }
+    static JSC::GCClient::IsoSubspace* subspaceForImpl(JSC::VM& vm);
+
+    JSCompressionStream(JSC::Structure*, JSDOMGlobalObject&);
+    void finishCreation(JSC::VM&);
+};
+
+} // namespace WebCore

src/bun.js/bindings/JSDecompressionStream.cpp

@@ -0,0 +1,139 @@
+#include "config.h"
+#include "JSDecompressionStream.h"
+
+#include "JSDOMBuiltinConstructor.h"
+#include "JSDOMGlobalObjectInlines.h"
+#include "WebCoreJSClientData.h"
+#include "WebCoreJSBuiltins.h"
+#include <JavaScriptCore/FunctionPrototype.h>
+#include <JavaScriptCore/JSCInlines.h>
+
+namespace WebCore {
+
+using namespace JSC;
+
+static JSC_DECLARE_CUSTOM_GETTER(jsDecompressionStreamConstructor);
+
+class JSDecompressionStreamPrototype final : public JSC::JSNonFinalObject {
+public:
+    using Base = JSC::JSNonFinalObject;
+    static JSDecompressionStreamPrototype* create(JSC::VM& vm, JSDOMGlobalObject* globalObject, JSC::Structure* structure)
+    {
+        JSDecompressionStreamPrototype* ptr = new (NotNull, JSC::allocateCell<JSDecompressionStreamPrototype>(vm)) JSDecompressionStreamPrototype(vm, globalObject, structure);
+        ptr->finishCreation(vm);
+        return ptr;
+    }
+
+    DECLARE_INFO;
+    template<typename CellType, JSC::SubspaceAccess>
+    static JSC::GCClient::IsoSubspace* subspaceFor(JSC::VM& vm)
+    {
+        STATIC_ASSERT_ISO_SUBSPACE_SHARABLE(JSDecompressionStreamPrototype, Base);
+        return &vm.plainObjectSpace();
+    }
+
+    static JSC::Structure* createStructure(JSC::VM& vm, JSC::JSGlobalObject* globalObject, JSC::JSValue prototype)
+    {
+        return JSC::Structure::create(vm, globalObject, prototype, JSC::TypeInfo(JSC::ObjectType, StructureFlags), info());
+    }
+
+private:
+    JSDecompressionStreamPrototype(JSC::VM& vm, JSC::JSGlobalObject*, JSC::Structure* structure)
+        : JSC::JSNonFinalObject(vm, structure)
+    {
+    }
+
+    void finishCreation(JSC::VM&);
+};
+STATIC_ASSERT_ISO_SUBSPACE_SHARABLE(JSDecompressionStreamPrototype, JSDecompressionStreamPrototype::Base);
+
+using JSDecompressionStreamDOMConstructor = JSDOMBuiltinConstructor<JSDecompressionStream>;
+
+template<> const ClassInfo JSDecompressionStreamDOMConstructor::s_info = { "DecompressionStream"_s, &Base::s_info, nullptr, nullptr, CREATE_METHOD_TABLE(JSDecompressionStreamDOMConstructor) };
+
+template<> JSValue JSDecompressionStreamDOMConstructor::prototypeForStructure(JSC::VM& vm, const JSDOMGlobalObject& globalObject)
+{
+    UNUSED_PARAM(vm);
+    return globalObject.functionPrototype();
+}
+
+template<> void JSDecompressionStreamDOMConstructor::initializeProperties(VM& vm, JSDOMGlobalObject& globalObject)
+{
+    putDirect(vm, vm.propertyNames->length, jsNumber(0), JSC::PropertyAttribute::ReadOnly | JSC::PropertyAttribute::DontEnum);
+    JSString* nameString = jsNontrivialString(vm, "DecompressionStream"_s);
+    m_originalName.set(vm, this, nameString);
+    putDirect(vm, vm.propertyNames->name, nameString, JSC::PropertyAttribute::ReadOnly | JSC::PropertyAttribute::DontEnum);
+    putDirect(vm, vm.propertyNames->prototype, JSDecompressionStream::prototype(vm, globalObject), JSC::PropertyAttribute::ReadOnly | JSC::PropertyAttribute::DontEnum | JSC::PropertyAttribute::DontDelete);
+}
+
+template<> FunctionExecutable* JSDecompressionStreamDOMConstructor::initializeExecutable(VM& vm)
+{
+    return decompressionStreamInitializeDecompressionStreamCodeGenerator(vm);
+}
+
+static const HashTableValue JSDecompressionStreamPrototypeTableValues[] = {
+    { "constructor"_s, static_cast<unsigned>(JSC::PropertyAttribute::DontEnum), NoIntrinsic, { HashTableValue::GetterSetterType, jsDecompressionStreamConstructor, 0 } },
+    { "readable"_s, static_cast<unsigned>(JSC::PropertyAttribute::DontEnum | JSC::PropertyAttribute::ReadOnly | JSC::PropertyAttribute::Accessor | JSC::PropertyAttribute::Builtin), NoIntrinsic, { HashTableValue::BuiltinAccessorType, decompressionStreamReadableCodeGenerator, 0 } },
+    { "writable"_s, static_cast<unsigned>(JSC::PropertyAttribute::DontEnum | JSC::PropertyAttribute::ReadOnly | JSC::PropertyAttribute::Accessor | JSC::PropertyAttribute::Builtin), NoIntrinsic, { HashTableValue::BuiltinAccessorType, decompressionStreamWritableCodeGenerator, 0 } },
+};
+
+const ClassInfo JSDecompressionStreamPrototype::s_info = { "DecompressionStream"_s, &Base::s_info, nullptr, nullptr, CREATE_METHOD_TABLE(JSDecompressionStreamPrototype) };
+
+void JSDecompressionStreamPrototype::finishCreation(VM& vm)
+{
+    Base::finishCreation(vm);
+    reifyStaticProperties(vm, JSDecompressionStream::info(), JSDecompressionStreamPrototypeTableValues, *this);
+    JSC_TO_STRING_TAG_WITHOUT_TRANSITION();
+}
+
+const ClassInfo JSDecompressionStream::s_info = { "DecompressionStream"_s, &Base::s_info, nullptr, nullptr, CREATE_METHOD_TABLE(JSDecompressionStream) };
+
+JSC::GCClient::IsoSubspace* JSDecompressionStream::subspaceForImpl(JSC::VM& vm)
+{
+    return WebCore::subspaceForImpl<JSDecompressionStream, UseCustomHeapCellType::No>(
+        vm,
+        [](auto& spaces) { return spaces.m_clientSubspaceForDecompressionStream.get(); },
+        [](auto& spaces, auto&& space) { spaces.m_clientSubspaceForDecompressionStream = std::forward<decltype(space)>(space); },
+        [](auto& spaces) { return spaces.m_subspaceForDecompressionStream.get(); },
+        [](auto& spaces, auto&& space) { spaces.m_subspaceForDecompressionStream = std::forward<decltype(space)>(space); });
+}
+
+JSDecompressionStream::JSDecompressionStream(Structure* structure, JSDOMGlobalObject& globalObject)
+    : JSDOMObject(structure, globalObject)
+{
+}
+
+void JSDecompressionStream::finishCreation(VM& vm)
+{
+    Base::finishCreation(vm);
+    ASSERT(inherits(info()));
+}
+
+JSObject* JSDecompressionStream::createPrototype(VM& vm, JSDOMGlobalObject& globalObject)
+{
+    auto* structure = JSDecompressionStreamPrototype::createStructure(vm, &globalObject, globalObject.objectPrototype());
+    structure->setMayBePrototype(true);
+    return JSDecompressionStreamPrototype::create(vm, &globalObject, structure);
+}
+
+JSObject* JSDecompressionStream::prototype(VM& vm, JSDOMGlobalObject& globalObject)
+{
+    return getDOMPrototype<JSDecompressionStream>(vm, globalObject);
+}
+
+JSValue JSDecompressionStream::getConstructor(VM& vm, const JSGlobalObject* globalObject)
+{
+    return getDOMConstructor<JSDecompressionStreamDOMConstructor, DOMConstructorID::DecompressionStream>(vm, *jsCast<const JSDOMGlobalObject*>(globalObject));
+}
+
+JSC_DEFINE_CUSTOM_GETTER(jsDecompressionStreamConstructor, (JSGlobalObject * lexicalGlobalObject, EncodedJSValue thisValue, PropertyName))
+{
+    auto& vm = JSC::getVM(lexicalGlobalObject);
+    auto throwScope = DECLARE_THROW_SCOPE(vm);
+    auto* prototype = jsDynamicCast<JSDecompressionStreamPrototype*>(JSValue::decode(thisValue));
+    if (!prototype)
+        return throwVMTypeError(lexicalGlobalObject, throwScope);
+    return JSValue::encode(JSDecompressionStream::getConstructor(vm, lexicalGlobalObject));
+}
+
+} // namespace WebCore

src/bun.js/bindings/JSDecompressionStream.h

@@ -0,0 +1,40 @@
+#pragma once
+
+#include "JSDOMWrapper.h"
+
+namespace WebCore {
+
+class JSDecompressionStream : public JSDOMObject {
+public:
+    using Base = JSDOMObject;
+    static JSDecompressionStream* create(JSC::Structure* structure, JSDOMGlobalObject* globalObject)
+    {
+        JSDecompressionStream* ptr = new (NotNull, JSC::allocateCell<JSDecompressionStream>(globalObject->vm())) JSDecompressionStream(structure, *globalObject);
+        ptr->finishCreation(globalObject->vm());
+        return ptr;
+    }
+
+    static JSC::JSObject* createPrototype(JSC::VM&, JSDOMGlobalObject&);
+    static JSC::JSObject* prototype(JSC::VM&, JSDOMGlobalObject&);
+    static JSC::JSValue getConstructor(JSC::VM&, const JSC::JSGlobalObject*);
+
+    DECLARE_INFO;
+
+    static JSC::Structure* createStructure(JSC::VM& vm, JSC::JSGlobalObject* globalObject, JSC::JSValue prototype)
+    {
+        return JSC::Structure::create(vm, globalObject, prototype, JSC::TypeInfo(JSC::ObjectType, StructureFlags), info());
+    }
+
+    template<typename, JSC::SubspaceAccess mode> static JSC::GCClient::IsoSubspace* subspaceFor(JSC::VM& vm)
+    {
+        if constexpr (mode == JSC::SubspaceAccess::Concurrently)
+            return nullptr;
+        return subspaceForImpl(vm);
+    }
+    static JSC::GCClient::IsoSubspace* subspaceForImpl(JSC::VM& vm);
+
+    JSDecompressionStream(JSC::Structure*, JSDOMGlobalObject&);
+    void finishCreation(JSC::VM&);
+};
+
+} // namespace WebCore

src/bun.js/bindings/ZigGlobalObject.cpp

@@ -78,6 +78,8 @@
 #include "JSAbortAlgorithm.h"
 #include "JSAbortController.h"
 #include "JSAbortSignal.h"
+#include "JSCompressionStream.h"
+#include "JSDecompressionStream.h"
 #include "JSBroadcastChannel.h"
 #include "JSBuffer.h"
 #include "JSBufferList.h"
@@ -962,9 +964,11 @@ WEBCORE_GENERATED_CONSTRUCTOR_GETTER(AbortSignal);
 WEBCORE_GENERATED_CONSTRUCTOR_GETTER(BroadcastChannel);
 WEBCORE_GENERATED_CONSTRUCTOR_GETTER(ByteLengthQueuingStrategy)
 WEBCORE_GENERATED_CONSTRUCTOR_GETTER(CloseEvent);
+WEBCORE_GENERATED_CONSTRUCTOR_GETTER(CompressionStream);
 WEBCORE_GENERATED_CONSTRUCTOR_GETTER(CountQueuingStrategy)
 WEBCORE_GENERATED_CONSTRUCTOR_GETTER(CryptoKey);
 WEBCORE_GENERATED_CONSTRUCTOR_GETTER(CustomEvent);
+WEBCORE_GENERATED_CONSTRUCTOR_GETTER(DecompressionStream);
 WEBCORE_GENERATED_CONSTRUCTOR_GETTER(DOMException);
 WEBCORE_GENERATED_CONSTRUCTOR_GETTER(DOMFormData);
 WEBCORE_GENERATED_CONSTRUCTOR_GETTER(DOMURL);

src/bun.js/bindings/ZigGlobalObject.lut.txt

@@ -48,9 +48,11 @@
   BroadcastChannel                BroadcastChannelConstructorCallback                  PropertyCallback
   ByteLengthQueuingStrategy       ByteLengthQueuingStrategyConstructorCallback         PropertyCallback
   CloseEvent                      CloseEventConstructorCallback                        PropertyCallback
+  CompressionStream               CompressionStreamConstructorCallback                 PropertyCallback
   CountQueuingStrategy            CountQueuingStrategyConstructorCallback              PropertyCallback
   CryptoKey                       CryptoKeyConstructorCallback                         PropertyCallback
   CustomEvent                     CustomEventConstructorCallback                       PropertyCallback
+  DecompressionStream             DecompressionStreamConstructorCallback               PropertyCallback
   DOMException                    DOMExceptionConstructorCallback                      PropertyCallback
   ErrorEvent                      ErrorEventConstructorCallback                        PropertyCallback
   Event                           EventConstructorCallback                             PropertyCallback

src/bun.js/bindings/js_classes.ts

@@ -8,4 +8,6 @@ export default [
   ["WritableStream", "JSWritableStream.h"],
   ["TransformStream", "JSTransformStream.h"],
   ["ArrayBuffer"],
+  ["CompressionStream", "JSCompressionStream.h"],
+  ["DecompressionStream", "JSDecompressionStream.h"],
 ];

src/bun.js/bindings/webcore/DOMClientIsoSubspaces.h

@@ -283,6 +283,8 @@ public:
     std::unique_ptr<GCClient::IsoSubspace> m_clientSubspaceForReadableStreamSource;
     std::unique_ptr<GCClient::IsoSubspace> m_clientSubspaceForTransformStream;
     std::unique_ptr<GCClient::IsoSubspace> m_clientSubspaceForTransformStreamDefaultController;
+    std::unique_ptr<GCClient::IsoSubspace> m_clientSubspaceForCompressionStream;
+    std::unique_ptr<GCClient::IsoSubspace> m_clientSubspaceForDecompressionStream;
     std::unique_ptr<GCClient::IsoSubspace> m_clientSubspaceForWritableStream;
     std::unique_ptr<GCClient::IsoSubspace> m_clientSubspaceForWritableStreamDefaultController;
     std::unique_ptr<GCClient::IsoSubspace> m_clientSubspaceForWritableStreamDefaultWriter;

src/bun.js/bindings/webcore/DOMConstructors.h

@@ -198,6 +198,8 @@ enum class DOMConstructorID : uint16_t {
     ReadableStreamSource,
     TransformStream,
     TransformStreamDefaultController,
+    CompressionStream,
+    DecompressionStream,
     WritableStream,
     WritableStreamDefaultController,
     WritableStreamDefaultWriter,
@@ -860,7 +862,7 @@ enum class DOMConstructorID : uint16_t {
     EventEmitter,
 };
 
-static constexpr unsigned numberOfDOMConstructorsBase = 846;
+static constexpr unsigned numberOfDOMConstructorsBase = 848;
 
 static constexpr unsigned bunExtraConstructors = 3;
 

src/bun.js/bindings/webcore/DOMIsoSubspaces.h

@@ -266,6 +266,8 @@ public:
     std::unique_ptr<IsoSubspace> m_subspaceForReadableStreamSource;
     std::unique_ptr<IsoSubspace> m_subspaceForTransformStream;
     std::unique_ptr<IsoSubspace> m_subspaceForTransformStreamDefaultController;
+    std::unique_ptr<IsoSubspace> m_subspaceForCompressionStream;
+    std::unique_ptr<IsoSubspace> m_subspaceForDecompressionStream;
     std::unique_ptr<IsoSubspace> m_subspaceForWritableStream;
     std::unique_ptr<IsoSubspace> m_subspaceForWritableStreamDefaultController;
     std::unique_ptr<IsoSubspace> m_subspaceForWritableStreamDefaultWriter;

src/codegen/bundle-modules.ts

@@ -532,7 +532,7 @@ declare module "module" {
 `;
 
     for (const [name] of jsclasses) {
-      dts += `\ndeclare function $inherits${name}(value: any): boolean;`;
+      dts += `\ndeclare function $inherits${name}(value: any): value is ${name};`;
     }
 
     return dts;

src/js/builtins/CompressionStream.ts

@@ -0,0 +1,33 @@
+export function initializeCompressionStream(this, format) {
+  const zlib = require("node:zlib");
+  const stream = require("node:stream");
+
+  const builders = {
+    "deflate": zlib.createDeflate,
+    "deflate-raw": zlib.createDeflateRaw,
+    "gzip": zlib.createGzip,
+    "brotli": zlib.createBrotliCompress,
+    "zstd": zlib.createZstdCompress,
+  };
+
+  if (!(format in builders))
+    throw $ERR_INVALID_ARG_VALUE("format", format, "must be one of: " + Object.keys(builders).join(", "));
+
+  const handle = builders[format]();
+  $putByIdDirectPrivate(this, "readable", stream.Readable.toWeb(handle));
+  $putByIdDirectPrivate(this, "writable", stream.Writable.toWeb(handle));
+
+  return this;
+}
+
+$getter;
+export function readable(this) {
+  if (!$inheritsCompressionStream(this)) throw $makeGetterTypeError("CompressionStream", "readable");
+  return $getByIdDirectPrivate(this, "readable");
+}
+
+$getter;
+export function writable(this) {
+  if (!$inheritsCompressionStream(this)) throw $makeGetterTypeError("CompressionStream", "writable");
+  return $getByIdDirectPrivate(this, "writable");
+}

src/js/builtins/DecompressionStream.ts

@@ -0,0 +1,33 @@
+export function initializeDecompressionStream(this, format) {
+  const zlib = require("node:zlib");
+  const stream = require("node:stream");
+
+  const builders = {
+    "deflate": zlib.createInflate,
+    "deflate-raw": zlib.createInflateRaw,
+    "gzip": zlib.createGunzip,
+    "brotli": zlib.createBrotliDecompress,
+    "zstd": zlib.createZstdDecompress,
+  };
+
+  if (!(format in builders))
+    throw $ERR_INVALID_ARG_VALUE("format", format, "must be one of: " + Object.keys(builders).join(", "));
+
+  const handle = builders[format]();
+  $putByIdDirectPrivate(this, "readable", stream.Readable.toWeb(handle));
+  $putByIdDirectPrivate(this, "writable", stream.Writable.toWeb(handle));
+
+  return this;
+}
+
+$getter;
+export function readable(this) {
+  if (!$inheritsDecompressionStream(this)) throw $makeGetterTypeError("DecompressionStream", "readable");
+  return $getByIdDirectPrivate(this, "readable");
+}
+
+$getter;
+export function writable(this) {
+  if (!$inheritsDecompressionStream(this)) throw $makeGetterTypeError("DecompressionStream", "writable");
+  return $getByIdDirectPrivate(this, "writable");
+}

src/js/node/stream.web.ts

@@ -15,6 +15,6 @@ export default {
   CountQueuingStrategy,
   TextEncoderStream,
   TextDecoderStream,
-  CompressionStream: undefined,
-  DecompressionStream: undefined,
+  CompressionStream,
+  DecompressionStream,
 };

test/integration/bun-types/fixture/streams.ts

@@ -59,6 +59,8 @@ expectType(node_stream.blob()).is<Promise<Blob>>();
 
 Bun.file("./foo.csv").stream().pipeThrough(new TextDecoderStream()).pipeThrough(new TextEncoderStream());
 
+Bun.file("./foo.csv").stream().pipeThrough(new CompressionStream("gzip")).pipeThrough(new DecompressionStream("gzip"));
+
 Bun.file("./foo.csv")
   .stream()
   .pipeThrough(new TextDecoderStream())

test/js/node/test/parallel/test-global-webstreams.js

@@ -0,0 +1,24 @@
+'use strict';
+
+require('../common');
+
+const assert = require('assert');
+const webstreams = require('stream/web');
+
+assert.strictEqual(ReadableStream, webstreams.ReadableStream);
+assert.strictEqual(ReadableStreamDefaultReader, webstreams.ReadableStreamDefaultReader);
+assert.strictEqual(ReadableStreamBYOBReader, webstreams.ReadableStreamBYOBReader);
+assert.strictEqual(ReadableStreamBYOBRequest, webstreams.ReadableStreamBYOBRequest);
+assert.strictEqual(ReadableByteStreamController, webstreams.ReadableByteStreamController);
+assert.strictEqual(ReadableStreamDefaultController, webstreams.ReadableStreamDefaultController);
+assert.strictEqual(TransformStream, webstreams.TransformStream);
+assert.strictEqual(TransformStreamDefaultController, webstreams.TransformStreamDefaultController);
+assert.strictEqual(WritableStream, webstreams.WritableStream);
+assert.strictEqual(WritableStreamDefaultWriter, webstreams.WritableStreamDefaultWriter);
+assert.strictEqual(WritableStreamDefaultController, webstreams.WritableStreamDefaultController);
+assert.strictEqual(ByteLengthQueuingStrategy, webstreams.ByteLengthQueuingStrategy);
+assert.strictEqual(CountQueuingStrategy, webstreams.CountQueuingStrategy);
+assert.strictEqual(TextEncoderStream, webstreams.TextEncoderStream);
+assert.strictEqual(TextDecoderStream, webstreams.TextDecoderStream);
+assert.strictEqual(CompressionStream, webstreams.CompressionStream);
+assert.strictEqual(DecompressionStream, webstreams.DecompressionStream);

test/js/node/test/parallel/test-whatwg-webstreams-compression.js

@@ -0,0 +1,70 @@
+// Flags: --no-warnings
+'use strict';
+
+const common = require('../common');
+
+const {
+  CompressionStream,
+  DecompressionStream,
+} = require('stream/web');
+
+const assert = require('assert');
+const dec = new TextDecoder();
+
+async function test(format) {
+  const gzip = new CompressionStream(format);
+  const gunzip = new DecompressionStream(format);
+
+  assert.strictEqual(gzip[Symbol.toStringTag], 'CompressionStream');
+  assert.strictEqual(gunzip[Symbol.toStringTag], 'DecompressionStream');
+
+  gzip.readable.pipeTo(gunzip.writable).then(common.mustCall());
+
+  const reader = gunzip.readable.getReader();
+  const writer = gzip.writable.getWriter();
+
+  const compressed_data = [];
+  const reader_function = ({ value, done }) => {
+    if (value)
+      compressed_data.push(value);
+    if (!done)
+      return reader.read().then(reader_function);
+    assert.strictEqual(dec.decode(Buffer.concat(compressed_data)), 'hello');
+  };
+  const reader_promise = reader.read().then(reader_function);
+
+  await Promise.all([
+    reader_promise,
+    reader_promise.then(() => reader.read().then(({ done }) => assert(done))),
+    writer.write('hello'),
+    writer.close(),
+  ]);
+}
+
+Promise.all(['gzip', 'deflate', 'deflate-raw', 'brotli', 'zstd'].map((i) => test(i))).then(common.mustCall());
+
+[1, 'hello', false, {}].forEach((i) => {
+  assert.throws(() => new CompressionStream(i), {
+    code: 'ERR_INVALID_ARG_VALUE',
+  });
+  assert.throws(() => new DecompressionStream(i), {
+    code: 'ERR_INVALID_ARG_VALUE',
+  });
+});
+
+assert.throws(
+  () => Reflect.get(CompressionStream.prototype, 'readable', {}), {
+    name: 'TypeError',
+  });
+assert.throws(
+  () => Reflect.get(CompressionStream.prototype, 'writable', {}), {
+    name: 'TypeError',
+  });
+assert.throws(
+  () => Reflect.get(DecompressionStream.prototype, 'readable', {}), {
+    name: 'TypeError',
+  });
+assert.throws(
+  () => Reflect.get(DecompressionStream.prototype, 'writable', {}), {
+    name: 'TypeError',
+  });