From 30075314818f09f8dd121f971e6c7462a25683ea Mon Sep 17 00:00:00 2001
From: Halid Odat <halidodat@gmail.com>
Date: Fri, 8 Apr 2022 20:27:13 +0000
Subject: [PATCH] Fix `ArrayBuffer.isView()` (#2019)

`ArrayBuffer.isView()` should check whether the object contains a `[[ViewedArrayBuffer]]` internal slot, which `DataView` has.

It changes the following:
- Fix `ArrayBuffer.isView()`
---
 boa_engine/src/builtins/array_buffer/mod.rs |  2 +-
 boa_engine/src/object/mod.rs                | 17 +++++++++++++++++
 2 files changed, 18 insertions(+), 1 deletion(-)

diff --git a/boa_engine/src/builtins/array_buffer/mod.rs b/boa_engine/src/builtins/array_buffer/mod.rs
index b4d59d1f4b..e36ddf7a7f 100644
--- a/boa_engine/src/builtins/array_buffer/mod.rs
+++ b/boa_engine/src/builtins/array_buffer/mod.rs
@@ -128,7 +128,7 @@ impl ArrayBuffer {
         Ok(args
             .get_or_undefined(0)
             .as_object()
-            .map(|obj| obj.borrow().is_typed_array())
+            .map(|obj| obj.borrow().has_viewed_array_buffer())
             .unwrap_or_default()
             .into())
     }
diff --git a/boa_engine/src/object/mod.rs b/boa_engine/src/object/mod.rs
index 9b33d425c4..206e7d2c10 100644
--- a/boa_engine/src/object/mod.rs
+++ b/boa_engine/src/object/mod.rs
@@ -519,6 +519,23 @@ impl Object {
         }
     }
 
+    #[inline]
+    pub(crate) fn has_viewed_array_buffer(&self) -> bool {
+        self.is_typed_array() || self.is_data_view()
+    }
+
+    /// Checks if it an `DataView` object.
+    #[inline]
+    pub fn is_data_view(&self) -> bool {
+        matches!(
+            self.data,
+            ObjectData {
+                kind: ObjectKind::DataView(_),
+                ..
+            }
+        )
+    }
+
     /// Checks if it an `ArrayBuffer` object.
     #[inline]
     pub fn is_array_buffer(&self) -> bool {