Support using `WTF::StringImpl` from Zig (#3279)

* Fix `make headers`

* [JS parser] Fix bug with printing non-ascii import paths in ascii mode

* Introduce `bun.String`

* Add test for non-ascii imports & entry points

* Add comment

* Fix build issue

* Support HTTP server

* Make it print the same

---------

Co-authored-by: Jarred Sumner <709451+Jarred-Sumner@users.noreply.github.com>

1 files changed, 141 insertions, 0 deletions

diff --git a/src/bun.js/bindings/BunString.cpp b/src/bun.js/bindings/BunString.cpp
new file mode 100644
index 000000000..797f66545
--- /dev/null
+++ b/src/bun.js/bindings/BunString.cpp
@@ -0,0 +1,141 @@
+#include "root.h"
+#include "headers-handwritten.h"
+#include "JavaScriptCore/JSCJSValueInlines.h"
+#include "helpers.h"
+
+using namespace JSC;
+
+extern "C" void Bun__WTFStringImpl__deref(WTF::StringImpl* impl)
+{
+    impl->deref();
+}
+extern "C" void Bun__WTFStringImpl__ref(WTF::StringImpl* impl)
+{
+    impl->ref();
+}
+
+extern "C" bool BunString__fromJS(JSC::JSGlobalObject* globalObject, JSC::EncodedJSValue encodedValue, BunString* bunString)
+{
+    JSC::JSValue value = JSC::JSValue::decode(encodedValue);
+    *bunString = Bun::toString(globalObject, value);
+    return bunString->tag != BunStringTag::Dead;
+}
+
+namespace Bun {
+JSC::JSValue toJS(JSC::JSGlobalObject* globalObject, BunString bunString)
+{
+    if (bunString.tag == BunStringTag::Empty || bunString.tag == BunStringTag::Dead) {
+        return JSValue(JSC::jsEmptyString(globalObject->vm()));
+    }
+    if (bunString.tag == BunStringTag::WTFStringImpl) {
+        return JSValue(jsString(globalObject->vm(), String(bunString.impl.wtf)));
+    }
+
+    if (bunString.tag == BunStringTag::StaticZigString) {
+        return JSValue(jsString(globalObject->vm(), Zig::toStringStatic(bunString.impl.zig)));
+    }
+
+    return JSValue(Zig::toJSStringGC(bunString.impl.zig, globalObject));
+}
+
+WTF::String toWTFString(const BunString& bunString)
+{
+    if (bunString.tag == BunStringTag::ZigString) {
+        if (Zig::isTaggedUTF8Ptr(bunString.impl.zig.ptr)) {
+            return Zig::toStringCopy(bunString.impl.zig);
+        } else {
+            return Zig::toString(bunString.impl.zig);
+        }
+
+    } else if (bunString.tag == BunStringTag::StaticZigString) {
+        return Zig::toStringStatic(bunString.impl.zig);
+    }
+
+    if (bunString.tag == BunStringTag::WTFStringImpl) {
+        return WTF::String(bunString.impl.wtf);
+    }
+
+    return WTF::String();
+}
+
+BunString fromJS(JSC::JSGlobalObject* globalObject, JSValue value)
+{
+    JSC::JSString* str = value.toStringOrNull(globalObject);
+    if (UNLIKELY(!str)) {
+        return { BunStringTag::Dead };
+    }
+
+    if (str->length() == 0) {
+        return { BunStringTag::Empty };
+    }
+
+    auto wtfString = str->value(globalObject);
+
+    return { BunStringTag::WTFStringImpl, { .wtf = wtfString.impl() } };
+}
+
+BunString toString(JSC::JSGlobalObject* globalObject, JSValue value)
+{
+    return fromJS(globalObject, value);
+}
+
+BunString toString(WTF::String& wtfString)
+{
+    if (wtfString.length() == 0)
+        return { BunStringTag::Empty };
+
+    return { BunStringTag::WTFStringImpl, { .wtf = wtfString.impl() } };
+}
+BunString toString(const WTF::String& wtfString)
+{
+    if (wtfString.length() == 0)
+        return { BunStringTag::Empty };
+
+    return { BunStringTag::WTFStringImpl, { .wtf = wtfString.impl() } };
+}
+BunString toString(WTF::StringImpl* wtfString)
+{
+    if (wtfString->length() == 0)
+        return { BunStringTag::Empty };
+
+    return { BunStringTag::WTFStringImpl, { .wtf = wtfString } };
+}
+
+BunString fromString(WTF::String& wtfString)
+{
+    if (wtfString.length() == 0)
+        return { BunStringTag::Empty };
+
+    return { BunStringTag::WTFStringImpl, { .wtf = wtfString.impl() } };
+}
+
+BunString fromString(WTF::StringImpl* wtfString)
+{
+    if (wtfString->length() == 0)
+        return { BunStringTag::Empty };
+
+    return { BunStringTag::WTFStringImpl, { .wtf = wtfString } };
+}
+
+}
+
+extern "C" JSC::EncodedJSValue BunString__toJS(JSC::JSGlobalObject* globalObject, BunString* bunString)
+{
+    return JSValue::encode(Bun::toJS(globalObject, *bunString));
+}
+
+extern "C" void BunString__toWTFString(BunString* bunString)
+{
+    if (bunString->tag == BunStringTag::ZigString) {
+        if (Zig::isTaggedUTF8Ptr(bunString->impl.zig.ptr)) {
+            bunString->impl.wtf = Zig::toStringCopy(bunString->impl.zig).impl();
+        } else {
+            bunString->impl.wtf = Zig::toString(bunString->impl.zig).impl();
+        }
+
+        bunString->tag = BunStringTag::WTFStringImpl;
+    } else if (bunString->tag == BunStringTag::StaticZigString) {
+        bunString->impl.wtf = Zig::toStringStatic(bunString->impl.zig).impl();
+        bunString->tag = BunStringTag::WTFStringImpl;
+    }
+}
\ No newline at end of file