Return function execution result from constructor if the function returned (#1463)

if the function returned

boa/src/builtins/regexp/mod.rs

@@ -1211,7 +1211,10 @@ impl RegExp {
         let flags = this.get_field("flags", context)?.to_string(context)?;
 
         // 6. Let matcher be ? Construct(C, « R, flags »).
-        let matcher = RegExp::constructor(&c, &[this.clone(), flags.clone().into()], context)?;
+        let matcher = c
+            .as_object()
+            .expect("SpeciesConstructor returned non Object")
+            .construct(&[this.clone(), flags.clone().into()], &c, context)?;
 
         // 7. Let lastIndex be ? ToLength(? Get(R, "lastIndex")).
         let last_index = this.get_field("lastIndex", context)?.to_length(context)?;
@@ -1592,8 +1595,10 @@ impl RegExp {
         };
 
         // 10. Let splitter be ? Construct(C, « rx, newFlags »).
-        let splitter =
-            RegExp::constructor(&constructor, &[this.clone(), new_flags.into()], context)?;
+        let splitter = constructor
+            .as_object()
+            .expect("SpeciesConstructor returned non Object")
+            .construct(&[Value::from(rx), new_flags.into()], &constructor, context)?;
 
         // 11. Let A be ! ArrayCreate(0).
         let a = Array::array_create(0, None, context).unwrap();

boa/src/object/gcobject.rs

@@ -12,6 +12,7 @@ use crate::{
         function_environment_record::{BindingStatus, FunctionEnvironmentRecord},
         lexical_environment::Environment,
     },
+    exec::InterpreterState,
     property::{PropertyDescriptor, PropertyKey},
     symbol::WellKnownSymbols,
     syntax::ast::node::RcStatementList,
@@ -312,6 +313,21 @@ impl GcObject {
                 context.pop_environment();
 
                 if construct {
+                    // https://tc39.es/ecma262/#sec-ecmascript-function-objects-construct-argumentslist-newtarget
+                    // 12. If result.[[Type]] is return, then
+                    if context.executor().get_current_state() == &InterpreterState::Return {
+                        // a. If Type(result.[[Value]]) is Object, return NormalCompletion(result.[[Value]]).
+                        if let Ok(v) = &result {
+                            if v.is_object() {
+                                return result;
+                            }
+                        }
+                    }
+
+                    // 13. Else, ReturnIfAbrupt(result).
+                    result?;
+
+                    // 14. Return ? constructorEnv.GetThisBinding().
                     this
                 } else {
                     result
@@ -785,12 +801,14 @@ impl GcObject {
         }
 
         // 4. If Type(C) is not Object, throw a TypeError exception.
-        if !c.is_object() {
+        let c = if let Some(c) = c.as_object() {
+            c
+        } else {
             return context.throw_type_error("property 'constructor' is not an object");
-        }
+        };
 
         // 5. Let S be ? Get(C, @@species).
-        let s = c.get_field(WellKnownSymbols::species(), context)?;
+        let s = c.get(WellKnownSymbols::species(), context)?;
 
         // 6. If S is either undefined or null, return defaultConstructor.
         if s.is_null_or_undefined() {