Return a `Buffer` object for fs.readFile

3 files changed, 54 insertions, 1 deletions

diff --git a/src/bun.js/base.zig b/src/bun.js/base.zig
index fac45dc59..c1bfbf544 100644
--- a/src/bun.js/base.zig
+++ b/src/bun.js/base.zig
@@ -2600,7 +2600,14 @@ pub const MarkedArrayBuffer = struct {
         return container;
     }
 
+    pub fn toNodeBuffer(this: MarkedArrayBuffer, ctx: js.JSContextRef) js.JSObjectRef {
+        return JSValue.createBufferWithCtx(ctx, this.buffer.byteSlice(), this.buffer.ptr, MarkedArrayBuffer_deallocator).asObjectRef();
+    }
+
     pub fn toJSObjectRef(this: MarkedArrayBuffer, ctx: js.JSContextRef, exception: js.ExceptionRef) js.JSObjectRef {
+        if (!this.buffer.value.isEmptyOrUndefinedOrNull()) {
+            return this.buffer.value.asObjectRef();
+        }
         return js.JSObjectMakeTypedArrayWithBytesNoCopy(
             ctx,
             this.buffer.typed_array_type.toC(),
diff --git a/src/bun.js/node/node_fs.zig b/src/bun.js/node/node_fs.zig
index a8bd7107d..29464b3a2 100644
--- a/src/bun.js/node/node_fs.zig
+++ b/src/bun.js/node/node_fs.zig
@@ -2290,7 +2290,7 @@ const Return = struct {
             };
         }
     };
-    pub const ReadFile = StringOrBuffer;
+    pub const ReadFile = JSC.Node.StringOrNodeBuffer;
     pub const Readlink = StringOrBuffer;
     pub const Realpath = StringOrBuffer;
     pub const RealpathNative = Realpath;
diff --git a/src/bun.js/node/types.zig b/src/bun.js/node/types.zig
index d6581a1cc..3a1f34fcd 100644
--- a/src/bun.js/node/types.zig
+++ b/src/bun.js/node/types.zig
@@ -222,6 +222,52 @@ pub const StringOrBuffer = union(Tag) {
     }
 };
 
+/// Like StringOrBuffer but actually returns a Node.js Buffer
+pub const StringOrNodeBuffer = union(Tag) {
+    string: string,
+    buffer: Buffer,
+
+    pub const Tag = enum { string, buffer };
+
+    pub fn slice(this: StringOrNodeBuffer) []const u8 {
+        return switch (this) {
+            .string => this.string,
+            .buffer => this.buffer.slice(),
+        };
+    }
+
+    pub fn toJS(this: StringOrNodeBuffer, ctx: JSC.C.JSContextRef, _: JSC.C.ExceptionRef) JSC.C.JSValueRef {
+        return switch (this) {
+            .string => {
+                const input = this.string;
+                if (strings.toUTF16Alloc(bun.default_allocator, input, false) catch null) |utf16| {
+                    bun.default_allocator.free(bun.constStrToU8(input));
+                    return JSC.ZigString.toExternalU16(utf16.ptr, utf16.len, ctx.ptr()).asObjectRef();
+                }
+
+                return JSC.ZigString.init(input).toExternalValue(ctx.ptr()).asObjectRef();
+            },
+            .buffer => this.buffer.toNodeBuffer(ctx),
+        };
+    }
+
+    pub fn fromJS(global: *JSC.JSGlobalObject, allocator: std.mem.Allocator, value: JSC.JSValue, exception: JSC.C.ExceptionRef) ?StringOrBuffer {
+        return switch (value.jsType()) {
+            JSC.JSValue.JSType.String, JSC.JSValue.JSType.StringObject, JSC.JSValue.JSType.DerivedStringObject, JSC.JSValue.JSType.Object => {
+                var zig_str = value.toSlice(global, allocator);
+                return StringOrNodeBuffer{ .string = zig_str.slice() };
+            },
+            JSC.JSValue.JSType.ArrayBuffer => StringOrNodeBuffer{
+                .buffer = Buffer.fromArrayBuffer(global.ref(), value, exception),
+            },
+            JSC.JSValue.JSType.Uint8Array, JSC.JSValue.JSType.DataView => StringOrBuffer{
+                .buffer = Buffer.fromArrayBuffer(global.ref(), value, exception),
+            },
+            else => null,
+        };
+    }
+};
+
 pub const SliceOrBuffer = union(Tag) {
     string: JSC.ZigString.Slice,
     buffer: Buffer,