Normative: consuming helpers close receiver on argument validation failure

Author: bakkot

spec.html

@@ -46794,8 +46794,11 @@ <h1>Iterator.prototype.every ( _predicate_ )</h1>
         <emu-alg>
           1. Let _O_ be the *this* value.
           1. If _O_ is not an Object, throw a *TypeError* exception.
-          1. If IsCallable(_predicate_) is *false*, throw a *TypeError* exception.
-          1. Let _iterated_ be ? GetIteratorDirect(_O_).
+          1. Let _iterated_ be the Iterator Record { [[Iterator]]: _O_, [[NextMethod]]: *undefined*, [[Done]]: *false* }.
+          1. If IsCallable(_predicate_) is *false*, then
+            1. Let _error_ be ThrowCompletion(a newly created *TypeError* object).
+            1. Return ? IteratorClose(_iterated_, _error_).
+          1. Set _iterated_ to ? GetIteratorDirect(_O_).
           1. Let _counter_ be 0.
           1. Repeat,
             1. Let _value_ be ? IteratorStepValue(_iterated_).
@@ -46841,8 +46844,11 @@ <h1>Iterator.prototype.find ( _predicate_ )</h1>
         <emu-alg>
           1. Let _O_ be the *this* value.
           1. If _O_ is not an Object, throw a *TypeError* exception.
-          1. If IsCallable(_predicate_) is *false*, throw a *TypeError* exception.
-          1. Let _iterated_ be ? GetIteratorDirect(_O_).
+          1. Let _iterated_ be the Iterator Record { [[Iterator]]: _O_, [[NextMethod]]: *undefined*, [[Done]]: *false* }.
+          1. If IsCallable(_predicate_) is *false*, then
+            1. Let _error_ be ThrowCompletion(a newly created *TypeError* object).
+            1. Return ? IteratorClose(_iterated_, _error_).
+          1. Set _iterated_ to ? GetIteratorDirect(_O_).
           1. Let _counter_ be 0.
           1. Repeat,
             1. Let _value_ be ? IteratorStepValue(_iterated_).
@@ -46899,8 +46905,11 @@ <h1>Iterator.prototype.forEach ( _procedure_ )</h1>
         <emu-alg>
           1. Let _O_ be the *this* value.
           1. If _O_ is not an Object, throw a *TypeError* exception.
-          1. If IsCallable(_procedure_) is *false*, throw a *TypeError* exception.
-          1. Let _iterated_ be ? GetIteratorDirect(_O_).
+          1. Let _iterated_ be the Iterator Record { [[Iterator]]: _O_, [[NextMethod]]: *undefined*, [[Done]]: *false* }.
+          1. If IsCallable(_procedure_) is *false*, then
+            1. Let _error_ be ThrowCompletion(a newly created *TypeError* object).
+            1. Return ? IteratorClose(_iterated_, _error_).
+          1. Set _iterated_ to ? GetIteratorDirect(_O_).
           1. Let _counter_ be 0.
           1. Repeat,
             1. Let _value_ be ? IteratorStepValue(_iterated_).
@@ -46944,8 +46953,11 @@ <h1>Iterator.prototype.reduce ( _reducer_ [ , _initialValue_ ] )</h1>
         <emu-alg>
           1. Let _O_ be the *this* value.
           1. If _O_ is not an Object, throw a *TypeError* exception.
-          1. If IsCallable(_reducer_) is *false*, throw a *TypeError* exception.
-          1. Let _iterated_ be ? GetIteratorDirect(_O_).
+          1. Let _iterated_ be the Iterator Record { [[Iterator]]: _O_, [[NextMethod]]: *undefined*, [[Done]]: *false* }.
+          1. If IsCallable(_reducer_) is *false*, then
+            1. Let _error_ be ThrowCompletion(a newly created *TypeError* object).
+            1. Return ? IteratorClose(_iterated_, _error_).
+          1. Set _iterated_ to ? GetIteratorDirect(_O_).
           1. If _initialValue_ is not present, then
             1. Let _accumulator_ be ? IteratorStepValue(_iterated_).
             1. If _accumulator_ is ~done~, throw a *TypeError* exception.
@@ -46969,8 +46981,11 @@ <h1>Iterator.prototype.some ( _predicate_ )</h1>
         <emu-alg>
           1. Let _O_ be the *this* value.
           1. If _O_ is not an Object, throw a *TypeError* exception.
-          1. If IsCallable(_predicate_) is *false*, throw a *TypeError* exception.
-          1. Let _iterated_ be ? GetIteratorDirect(_O_).
+          1. Let _iterated_ be the Iterator Record { [[Iterator]]: _O_, [[NextMethod]]: *undefined*, [[Done]]: *false* }.
+          1. If IsCallable(_predicate_) is *false*, then
+            1. Let _error_ be ThrowCompletion(a newly created *TypeError* object).
+            1. Return ? IteratorClose(_iterated_, _error_).
+          1. Set _iterated_ to ? GetIteratorDirect(_O_).
           1. Let _counter_ be 0.
           1. Repeat,
             1. Let _value_ be ? IteratorStepValue(_iterated_).