fix(object/operations,string): convert remaining panics to EngineError::Panic

Author: KaustubhOG

core/engine/src/object/internal_methods/string.rs

@@ -39,7 +39,7 @@ pub(crate) fn string_exotic_get_own_property(
         Ok(desc)
     } else {
         // 4. Return ! StringGetOwnProperty(S, P).
-        Ok(string_get_own_property(obj, key))
+        string_get_own_property(obj, key)
     }
 }
 
@@ -57,7 +57,7 @@ pub(crate) fn string_exotic_define_own_property(
 ) -> JsResult<bool> {
     // 1. Assert: IsPropertyKey(P) is true.
     // 2. Let stringDesc be ! StringGetOwnProperty(S, P).
-    let string_desc = string_get_own_property(obj, key);
+    let string_desc = string_get_own_property(obj, key)?;
 
     // 3. If stringDesc is not undefined, then
     if let Some(string_desc) = string_desc {
@@ -133,7 +133,10 @@ pub(crate) fn string_exotic_own_property_keys(
 ///  - [ECMAScript reference][spec]
 ///
 /// [spec]: https://tc39.es/ecma262/#sec-stringgetownproperty
-fn string_get_own_property(obj: &JsObject, key: &PropertyKey) -> Option<PropertyDescriptor> {
+fn string_get_own_property(
+    obj: &JsObject,
+    key: &PropertyKey,
+) -> JsResult<Option<PropertyDescriptor>> {
     // 1. Assert: S is an Object that has a [[StringData]] internal slot.
     // 2. Assert: IsPropertyKey(P) is true.
     // 3. If Type(P) is not String, return undefined.
@@ -143,20 +146,23 @@ fn string_get_own_property(obj: &JsObject, key: &PropertyKey) -> Option<Property
     // 7. If index is -0𝔽, return undefined.
     let pos = match key {
         PropertyKey::Index(index) => index.get() as usize,
-        _ => return None,
+        _ => return Ok(None),
     };
 
     // 8. Let str be S.[[StringData]].
     // 9. Assert: Type(str) is String.
     let string = obj
         .downcast_ref::<JsString>()
-        .expect("string exotic method should only be callable from string objects")
+        .js_expect("string exotic method should only be callable from string objects")?
         .clone();
 
     // 10. Let len be the length of str.
     // 11. If ℝ(index) < 0 or len ≤ ℝ(index), return undefined.
-    // 12. Let resultStr be the String value of length 1, containing one code unit from str, specifically the code unit at index ℝ(index).
-    let result_str = string.get(pos..=pos)?;
+    // 12. Let resultStr be the String value of length 1, containing one code unit from str,
+    //     specifically the code unit at index ℝ(index).
+    let Some(result_str) = string.get(pos..=pos) else {
+        return Ok(None);
+    };
 
     // 13. Return the PropertyDescriptor { [[Value]]: resultStr, [[Writable]]: false, [[Enumerable]]: true, [[Configurable]]: false }.
     let desc = PropertyDescriptor::builder()
@@ -166,5 +172,5 @@ fn string_get_own_property(obj: &JsObject, key: &PropertyKey) -> Option<Property
         .configurable(false)
         .build();
 
-    Some(desc)
+    Ok(Some(desc))
 }

core/engine/src/object/operations.rs

@@ -906,7 +906,7 @@ impl JsObject {
         // 4. Let from be ! ToObject(source).
         let from = source
             .to_object(context)
-            .expect("function ToObject should never complete abruptly here");
+            .js_expect("function ToObject should never complete abruptly here")?;
 
         // 5. Let keys be ? from.[[OwnPropertyKeys]]().
         // 6. For each element nextKey of keys, do
@@ -939,7 +939,9 @@ impl JsObject {
 
                     // 2. Perform ! CreateDataPropertyOrThrow(target, nextKey, propValue).
                     self.create_data_property_or_throw(key, prop_value, context)
-                        .expect("CreateDataPropertyOrThrow should never complete abruptly here");
+                        .js_expect(
+                            "CreateDataPropertyOrThrow should never complete abruptly here",
+                        )?;
                 }
             }
         }