add IEnumerable support

sebastienros · Sep 25, 2021 · 6b86b06 · 6b86b06
1 parent 858e741
commit 6b86b06
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Showing 4 changed files with 43 additions and 32 deletions.
diff --git a/Jint.Tests/Runtime/Domain/Company.cs b/Jint.Tests/Runtime/Domain/Company.cs
@@ -35,5 +35,13 @@ int IComparable<ICompany>.CompareTo(ICompany other)
         {
             return string.Compare(_name, other.Name, StringComparison.CurrentCulture);
         }
+
+        public IEnumerable<char> GetNameChars()
+        {
+            foreach (var c in _name)
+            {
+                yield return c;
+            }
+        }
     }
 }
diff --git a/Jint.Tests/Runtime/InteropTests.cs b/Jint.Tests/Runtime/InteropTests.cs
@@ -573,6 +573,16 @@ public void ShouldForOfOnExpandoObject()
             Assert.Equal("a,1b,2", result);
         }
 
+        [Fact]
+        public void ShouldForOfOnEnumerable()
+        {
+            _engine.SetValue("c", new Company("name"));
+
+            var result = _engine.Evaluate("var l = ''; for (var x of c.getNameChars()) l += x + ','; return l;").AsString();
+
+            Assert.Equal("n,a,m,e,", result);
+        }
+
         [Fact]
         public void ShouldThrowWhenForOfOnObject()
         {

diff --git a/Jint/Runtime/Interop/ObjectWrapper.cs b/Jint/Runtime/Interop/ObjectWrapper.cs
@@ -208,22 +208,19 @@ public override PropertyDescriptor GetOwnProperty(JsValue property)
                 return x;
             }
 
-            if (property.IsSymbol() && property == GlobalSymbolRegistry.Iterator)
+            // if we have array-like or dictionary or expando, we can provide iterator
+            if (property.IsSymbol() && property == GlobalSymbolRegistry.Iterator && _typeDescriptor.Iterable)
             {
-                // if we have array-like or dictionary or expando, we can provide iterator
-                if (_typeDescriptor.IsArrayLike || _typeDescriptor.IsDictionary)
-                {
-                    var iteratorFunction = new ClrFunctionInstance(
-                        Engine,
-                        "iterator",
-                        Iterator,
-                        1,
-                        PropertyFlag.Configurable);
-
-                    var iteratorProperty = new PropertyDescriptor(iteratorFunction, PropertyFlag.Configurable | PropertyFlag.Writable);
-                    SetProperty(GlobalSymbolRegistry.Iterator, iteratorProperty);
-                    return iteratorProperty;
-                }
+                var iteratorFunction = new ClrFunctionInstance(
+                    Engine,
+                    "iterator",
+                    Iterator,
+                    1,
+                    PropertyFlag.Configurable);
+
+                var iteratorProperty = new PropertyDescriptor(iteratorFunction, PropertyFlag.Configurable | PropertyFlag.Writable);
+                SetProperty(GlobalSymbolRegistry.Iterator, iteratorProperty);
+                return iteratorProperty;
             }
 
             var member = property.ToString();
@@ -259,14 +256,10 @@ ReflectionAccessor Factory()
         private static JsValue Iterator(JsValue thisObj, JsValue[] arguments)
         {
             var wrapper = (ObjectWrapper) thisObj;
-            var intrinsics = wrapper._engine.Realm.Intrinsics;
 
-            if (wrapper._typeDescriptor.IsDictionary)
-            {
-                return new DictionaryIterator(wrapper._engine, wrapper);
-            }
-
-            return new ListIterator(wrapper._engine, (IList) wrapper.Target);
+            return wrapper._typeDescriptor.IsDictionary
+                ? new DictionaryIterator(wrapper._engine, wrapper)
+                : new EnumerableIterator(wrapper._engine, (IEnumerable) wrapper.Target);
         }
 
         private static JsValue GetLength(JsValue thisObj, JsValue[] arguments)
@@ -332,23 +325,20 @@ public override bool TryIteratorStep(out ObjectInstance nextItem)
             }
         }
 
-        private sealed class ListIterator : IteratorInstance
+        private sealed class EnumerableIterator : IteratorInstance
         {
-            private readonly IList _list;
-            private int _position;
+            private readonly IEnumerator _enumerator;
 
-            public ListIterator(Engine engine, IList list) : base(engine)
+            public EnumerableIterator(Engine engine, IEnumerable target) : base(engine)
             {
-                _list = list;
-                _position = 0;
+                _enumerator = target.GetEnumerator();
             }
 
             public override bool TryIteratorStep(out ObjectInstance nextItem)
             {
-                if (_position < _list.Count)
+                if (_enumerator.MoveNext())
                 {
-                    var value = _list[_position];
-                    _position++;
+                    var value = _enumerator.Current;
                     nextItem = new ValueIteratorPosition(_engine, FromObject(_engine, value));
                     return true;
                 }
@@ -357,6 +347,5 @@ public override bool TryIteratorStep(out ObjectInstance nextItem)
                 return false;
             }
         }
-
     }
 }
diff --git a/Jint/Runtime/Interop/TypeDescriptor.cs b/Jint/Runtime/Interop/TypeDescriptor.cs
@@ -14,6 +14,7 @@ private TypeDescriptor(Type type)
         {
             IsArrayLike = DetermineIfObjectIsArrayLikeClrCollection(type);
             IsDictionary = typeof(IDictionary).IsAssignableFrom(type) || typeof(IDictionary<string, object>).IsAssignableFrom(type);
+            IsEnumerable = typeof(IEnumerable).IsAssignableFrom(type);
 
             if (IsArrayLike)
             {
@@ -25,8 +26,11 @@ private TypeDescriptor(Type type)
         public bool IsArrayLike { get; }
         public bool IsIntegerIndexedArray { get; }
         public bool IsDictionary { get; }
+        public bool IsEnumerable { get; }
         public PropertyInfo LengthProperty { get; }
 
+        public bool Iterable => IsArrayLike || IsDictionary || IsEnumerable;
+
         public static TypeDescriptor Get(Type type)
         {
             return _cache.GetOrAdd(type, t => new TypeDescriptor(t));