[iterator] Adapt Iterator Helpers to ECMA-262 PR 3776 [v8/v8 : main]

[Olivier Flückiger (Gerrit)]

Attention needed from Nikolaos Papaspyrou

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File-level comment, Patchset 2 (Latest):

Olivier Flückiger . resolved

ptal

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Gerrit-Change-Number: 7859692

Gerrit-PatchSet: 2

Gerrit-Owner: Olivier Flückiger <ol...@chromium.org>

Gerrit-Reviewer: Nikolaos Papaspyrou <niko...@chromium.org>

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[Nikolaos Papaspyrou (Gerrit)]

Attention needed from Olivier Flückiger

Nikolaos Papaspyrou voted and added 16 comments

Votes added by Nikolaos Papaspyrou

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+1

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Patchset-level comments

File-level comment, Patchset 2 (Latest):

Nikolaos Papaspyrou . resolved

LGTM, modulo my OCD...
Thanks Olivier!

File src/builtins/iterator-helpers.tq

Line 444, Patchset 2 (Latest):// https://tc39.es/ecma262/#sec-iteratorprototype.take

Nikolaos Papaspyrou . unresolved

```suggestion
// https://tc39.es/ecma262/#sec-iterator.prototype.take
```

Line 475, Patchset 2 (Latest): // If numLimit is finite and numLimit > 𝔽(2^53 - 1), then

Nikolaos Papaspyrou . unresolved

```suggestion
    // 7. If numLimit is finite and numLimit > 𝔽(2^53 - 1), then
```

Line 481, Patchset 2 (Latest): // 7. Let integerLimit be ! ToIntegerOrInfinity(numLimit).

Nikolaos Papaspyrou . unresolved

```suggestion
    // 8. Let integerLimit be ! ToIntegerOrInfinity(numLimit).
```

Line 484, Patchset 2 (Latest): // 8. If integerLimit < 0, then

Nikolaos Papaspyrou . unresolved

```suggestion
    // 9. If integerLimit < 0, then
```

Line 489, Patchset 2 (Latest): // 9. Set iterated to ? GetIteratorDirect(O).

Nikolaos Papaspyrou . unresolved

```suggestion
    // 10. Set iterated to ? GetIteratorDirect(O).
```

Line 492, Patchset 2 (Latest): // Step 10 implemented in IteratorTakeHelperNext

Nikolaos Papaspyrou . unresolved

```suggestion
    // Step 11 implemented in IteratorTakeHelperNext
```

Line 494, Patchset 2 (Latest): // 11. Let result be CreateIteratorFromClosure(closure, "Iterator Helper",
// %IteratorHelperPrototype%).
// 12. Set result.[[UnderlyingIterator]] to iterated.
// 13. Return result.
return NewJSIteratorTakeHelper(iterated, integerLimit);

Nikolaos Papaspyrou . unresolved

```suggestion
    // 12. Let result be CreateIteratorFromClosure(closure, "Iterator Helper",
    //     %IteratorHelperPrototype%).
    // 13. Set result.[[UnderlyingIterator]] to iterated.
    // 14. Return result.
    return NewJSIteratorTakeHelper(iterated, integerLimit);
```

Line 571, Patchset 2 (Latest):// https://tc39.es/ecma262/#sec-iteratorprototype.drop

Nikolaos Papaspyrou . unresolved

```suggestion
// https://tc39.es/ecma262/#sec-iterator.prototype.drop
```

Line 602, Patchset 2 (Latest): // If numLimit is finite and numLimit > 𝔽(2^53 - 1), then

Nikolaos Papaspyrou . unresolved

```suggestion
    // 7. If numLimit is finite and numLimit > 𝔽(2^53 - 1), then
```

Line 608, Patchset 2 (Latest): // 7. Let integerLimit be ! ToIntegerOrInfinity(numLimit).

Nikolaos Papaspyrou . unresolved

```suggestion
    // 8. Let integerLimit be ! ToIntegerOrInfinity(numLimit).
```

Line 611, Patchset 2 (Latest): // 8. If integerLimit < 0, then

Nikolaos Papaspyrou . unresolved

```suggestion
    // 9. If integerLimit < 0, then
```

Line 616, Patchset 2 (Latest): // 9. Let iterated be ? GetIteratorDirect(O).

Nikolaos Papaspyrou . unresolved

```suggestion
    // 10. Let iterated be ? GetIteratorDirect(O).
```

Line 619, Patchset 2 (Latest): // Step 10 implemented in IteratorDropHelperNext

Nikolaos Papaspyrou . unresolved

```suggestion
    // Step 11 implemented in IteratorDropHelperNext
```

Line 621, Patchset 2 (Latest): // 11. Let result be CreateIteratorFromClosure(closure, "Iterator Helper",
// %IteratorHelperPrototype%).
// 12. Set result.[[UnderlyingIterator]] to iterated.
// 13. Return result.

Nikolaos Papaspyrou . unresolved

```suggestion
    // 12. Let result be CreateIteratorFromClosure(closure, "Iterator Helper",
    //     %IteratorHelperPrototype%).
    // 13. Set result.[[UnderlyingIterator]] to iterated.
    // 14. Return result.
```

File test/mjsunit/harmony/iterator-take-drop-limit-range.js

Line 5, Patchset 2 (Latest):// Flags: --harmony-iterator-helpers

let closed = false;

Nikolaos Papaspyrou . unresolved

```suggestion
let closed = false;
```

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Gerrit-Change-Number: 7859692

Gerrit-PatchSet: 2

Gerrit-Owner: Olivier Flückiger <ol...@chromium.org>

Gerrit-Reviewer: Nikolaos Papaspyrou <niko...@chromium.org>

Gerrit-Reviewer: Olivier Flückiger <ol...@chromium.org>

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[Olivier Flückiger (Gerrit)]

Olivier Flückiger voted and added 16 comments

Votes added by Olivier Flückiger

Auto-Submit	+1
Commit-Queue	+2

16 comments

Patchset-level comments

File-level comment, Patchset 3 (Latest):

Olivier Flückiger . resolved

thank you and sorry for being such a lazy person 😊

File src/builtins/iterator-helpers.tq

Line 444, Patchset 2:// https://tc39.es/ecma262/#sec-iteratorprototype.take

Nikolaos Papaspyrou . resolved

```suggestion
// https://tc39.es/ecma262/#sec-iterator.prototype.take
```

Olivier Flückiger

Fix applied.

Line 475, Patchset 2: // If numLimit is finite and numLimit > 𝔽(2^53 - 1), then

Nikolaos Papaspyrou . resolved

```suggestion
    // 7. If numLimit is finite and numLimit > 𝔽(2^53 - 1), then
```

Olivier Flückiger

Fix applied.

Line 481, Patchset 2: // 7. Let integerLimit be ! ToIntegerOrInfinity(numLimit).

Nikolaos Papaspyrou . resolved

```suggestion
    // 8. Let integerLimit be ! ToIntegerOrInfinity(numLimit).
```

Olivier Flückiger

Fix applied.

Line 484, Patchset 2: // 8. If integerLimit < 0, then

Nikolaos Papaspyrou . resolved

```suggestion
    // 9. If integerLimit < 0, then
```

Olivier Flückiger

Fix applied.

Line 489, Patchset 2: // 9. Set iterated to ? GetIteratorDirect(O).

Nikolaos Papaspyrou . resolved

```suggestion
    // 10. Set iterated to ? GetIteratorDirect(O).
```

Olivier Flückiger

Fix applied.

Line 492, Patchset 2: // Step 10 implemented in IteratorTakeHelperNext

Nikolaos Papaspyrou . resolved

```suggestion
    // Step 11 implemented in IteratorTakeHelperNext
```

Olivier Flückiger

Fix applied.

Line 494, Patchset 2: // 11. Let result be CreateIteratorFromClosure(closure, "Iterator Helper",


// %IteratorHelperPrototype%).
// 12. Set result.[[UnderlyingIterator]] to iterated.
// 13. Return result.
return NewJSIteratorTakeHelper(iterated, integerLimit);

Nikolaos Papaspyrou . resolved

```suggestion
    // 12. Let result be CreateIteratorFromClosure(closure, "Iterator Helper",
    //     %IteratorHelperPrototype%).
    // 13. Set result.[[UnderlyingIterator]] to iterated.
    // 14. Return result.
    return NewJSIteratorTakeHelper(iterated, integerLimit);
```

Olivier Flückiger

Fix applied.

Line 571, Patchset 2:// https://tc39.es/ecma262/#sec-iteratorprototype.drop

Nikolaos Papaspyrou . resolved

```suggestion
// https://tc39.es/ecma262/#sec-iterator.prototype.drop
```

Olivier Flückiger

Fix applied.

Line 602, Patchset 2: // If numLimit is finite and numLimit > 𝔽(2^53 - 1), then

Nikolaos Papaspyrou . resolved

```suggestion
    // 7. If numLimit is finite and numLimit > 𝔽(2^53 - 1), then
```

Olivier Flückiger

Fix applied.

Line 608, Patchset 2: // 7. Let integerLimit be ! ToIntegerOrInfinity(numLimit).

Nikolaos Papaspyrou . resolved

```suggestion
    // 8. Let integerLimit be ! ToIntegerOrInfinity(numLimit).
```

Olivier Flückiger

Fix applied.

Line 611, Patchset 2: // 8. If integerLimit < 0, then

Nikolaos Papaspyrou . resolved

```suggestion
    // 9. If integerLimit < 0, then
```

Olivier Flückiger

Fix applied.

Line 616, Patchset 2: // 9. Let iterated be ? GetIteratorDirect(O).

Nikolaos Papaspyrou . resolved

```suggestion
    // 10. Let iterated be ? GetIteratorDirect(O).
```

Olivier Flückiger

Done

Line 619, Patchset 2: // Step 10 implemented in IteratorDropHelperNext

Nikolaos Papaspyrou . resolved

```suggestion
    // Step 11 implemented in IteratorDropHelperNext
```

Olivier Flückiger

Fix applied.

Line 621, Patchset 2: // 11. Let result be CreateIteratorFromClosure(closure, "Iterator Helper",


// %IteratorHelperPrototype%).
// 12. Set result.[[UnderlyingIterator]] to iterated.
// 13. Return result.

Nikolaos Papaspyrou . resolved

```suggestion
    // 12. Let result be CreateIteratorFromClosure(closure, "Iterator Helper",
    //     %IteratorHelperPrototype%).
    // 13. Set result.[[UnderlyingIterator]] to iterated.
    // 14. Return result.

```

Olivier Flückiger

Fix applied.

File test/mjsunit/harmony/iterator-take-drop-limit-range.js

Line 5, Patchset 2:// Flags: --harmony-iterator-helpers

let closed = false;

Nikolaos Papaspyrou . resolved

```suggestion
let closed = false;
```

Olivier Flückiger

Fix applied.

Open in Gerrit

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Gerrit-Change-Id: I27fa44e1ee6708edf8fa5fa62f5d7c5012ebdb7a

Gerrit-Change-Number: 7859692

Gerrit-PatchSet: 3

Gerrit-Owner: Olivier Flückiger <ol...@chromium.org>

Gerrit-Reviewer: Nikolaos Papaspyrou <niko...@chromium.org>

Gerrit-Reviewer: Olivier Flückiger <ol...@chromium.org>

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[v8-scoped@luci-project-accounts.iam.gserviceaccount.com (Gerrit)]

v8-s...@luci-project-accounts.iam.gserviceaccount.com submitted the change with unreviewed changes

Unreviewed changes

2 is the latest approved patch-set.
The change was submitted with unreviewed changes in the following files:

```
The name of the file: test/mjsunit/harmony/iterator-take-drop-limit-range.js
Insertions: 0, Deletions: 2.

@@ -2,8 +2,6 @@
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
-// Flags: --harmony-iterator-helpers
-
 let closed = false;
 function createMockIterator() {
   return {
```
```
The name of the file: src/builtins/iterator-helpers.tq
Insertions: 20, Deletions: 20.

@@ -441,7 +441,7 @@
   };
 }
 
-// https://tc39.es/ecma262/#sec-iteratorprototype.take
+// https://tc39.es/ecma262/#sec-iterator.prototype.take
 @incrementUseCounter('v8::Isolate::kIteratorMethods')
 transitioning javascript builtin IteratorPrototypeTake(
     js-implicit context: NativeContext, receiver: JSAny)(
@@ -472,29 +472,29 @@
     //   b. Return ? IteratorClose(iterated, error).
     if (NumberIsNaN(numLimit)) goto RangeError(o);
 
-    // If numLimit is finite and numLimit > 𝔽(2^53 - 1), then
+    // 7. If numLimit is finite and numLimit > 𝔽(2^53 - 1), then
     //   a. Let error be ThrowCompletion(a newly created RangeError object).
     //   b. Return ? IteratorClose(iterated, error).
     if (!NumberIsSomeInfinity(numLimit) && numLimit > kMaxSafeInteger)
       goto RangeError(o);
 
-    // 7. Let integerLimit be ! ToIntegerOrInfinity(numLimit).
+    // 8. Let integerLimit be ! ToIntegerOrInfinity(numLimit).
     const integerLimit = ToInteger_Inline(numLimit);
 
-    // 8. If integerLimit < 0, then
+    // 9. If integerLimit < 0, then
     //  a. Let error be ThrowCompletion(a newly created RangeError object).
     //  b. Return ? IteratorClose(iterated, error).
     if (integerLimit < 0) goto RangeError(o);
 
-    // 9. Set iterated to ? GetIteratorDirect(O).
+    // 10. Set iterated to ? GetIteratorDirect(O).
     const iterated = GetIteratorDirect(o);
 
-    // Step 10 implemented in IteratorTakeHelperNext
+    // Step 11 implemented in IteratorTakeHelperNext
 
-    // 11. Let result be CreateIteratorFromClosure(closure, "Iterator Helper",
-    //    %IteratorHelperPrototype%).
-    // 12. Set result.[[UnderlyingIterator]] to iterated.
-    // 13. Return result.
+    // 12. Let result be CreateIteratorFromClosure(closure, "Iterator Helper",
+    //     %IteratorHelperPrototype%).
+    // 13. Set result.[[UnderlyingIterator]] to iterated.
+    // 14. Return result.
     return NewJSIteratorTakeHelper(iterated, integerLimit);
   } label RangeError(iteratorObject: JSReceiver) deferred {
     IteratorCloseOnException(iteratorObject);
@@ -568,7 +568,7 @@
   };
 }
 
-// https://tc39.es/ecma262/#sec-iteratorprototype.drop
+// https://tc39.es/ecma262/#sec-iterator.prototype.drop
 @incrementUseCounter('v8::Isolate::kIteratorMethods')
 transitioning javascript builtin IteratorPrototypeDrop(
     js-implicit context: NativeContext, receiver: JSAny)(
@@ -599,29 +599,29 @@
     //   b. Return ? IteratorClose(iterated, error).
     if (NumberIsNaN(numLimit)) goto RangeError(o);
 
-    // If numLimit is finite and numLimit > 𝔽(2^53 - 1), then
+    // 7. If numLimit is finite and numLimit > 𝔽(2^53 - 1), then
     //   a. Let error be ThrowCompletion(a newly created RangeError object).
     //   b. Return ? IteratorClose(iterated, error).
     if (!NumberIsSomeInfinity(numLimit) && numLimit > kMaxSafeInteger)
       goto RangeError(o);
 
-    // 7. Let integerLimit be ! ToIntegerOrInfinity(numLimit).
+    // 8. Let integerLimit be ! ToIntegerOrInfinity(numLimit).
     const integerLimit = ToInteger_Inline(numLimit);
 
-    // 8. If integerLimit < 0, then
+    // 9. If integerLimit < 0, then
     //   a. Let error be ThrowCompletion(a newly created RangeError object).
     //   b. Return ? IteratorClose(iterated, error).
     if (integerLimit < 0) goto RangeError(o);
 
-    // 9. Let iterated be ? GetIteratorDirect(O).
+    // 10. Let iterated be ? GetIteratorDirect(O).
     const iterated = GetIteratorDirect(o);
 
-    // Step 10 implemented in IteratorDropHelperNext
+    // Step 11 implemented in IteratorDropHelperNext
 
-    // 11. Let result be CreateIteratorFromClosure(closure, "Iterator Helper",
-    //    %IteratorHelperPrototype%).
-    // 12. Set result.[[UnderlyingIterator]] to iterated.
-    // 13. Return result.
+    // 12. Let result be CreateIteratorFromClosure(closure, "Iterator Helper",
+    //     %IteratorHelperPrototype%).
+    // 13. Set result.[[UnderlyingIterator]] to iterated.
+    // 14. Return result.
     return NewJSIteratorDropHelper(iterated, integerLimit);
   } label RangeError(iteratorObject: JSReceiver) deferred {
     IteratorCloseOnException(iteratorObject);
```

Change information

Commit message:

[iterator] Adapt Iterator Helpers to ECMA-262 PR 3776

Aligns Iterator.prototype.take and Iterator.prototype.drop with the
normative changes in https://github.com/tc39/ecma262/pull/3776.
Specifically, if numLimit is finite and strictly greater than 2^53 - 1
(kMaxSafeInteger), V8 now correctly closes the iterator and throws a
RangeError.

TAG=agy
CONV=df8a3037-745d-4141-afa0-f7f025cb3248

Bug: 476989751

Change-Id: I27fa44e1ee6708edf8fa5fa62f5d7c5012ebdb7a

Reviewed-on: https://chromium-review.googlesource.com/c/v8/v8/+/7859692

Reviewed-by: Nikolaos Papaspyrou <niko...@chromium.org>

Commit-Queue: Olivier Flückiger <ol...@chromium.org>

Auto-Submit: Olivier Flückiger <ol...@chromium.org>

Cr-Commit-Position: refs/heads/main@{#107429}

Files:

• M src/builtins/iterator-helpers.tq
• A test/mjsunit/harmony/iterator-take-drop-limit-range.js

Change size: M

Delta: 2 files changed, 59 insertions(+), 18 deletions(-)

Branch: refs/heads/main

Submit Requirements:

• Code-Review: +1 by Nikolaos Papaspyrou

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Gerrit-MessageType: merged

Gerrit-Project: v8/v8

Gerrit-Branch: main

Gerrit-Change-Id: I27fa44e1ee6708edf8fa5fa62f5d7c5012ebdb7a

Gerrit-Change-Number: 7859692

Gerrit-PatchSet: 4

Gerrit-Owner: Olivier Flückiger <ol...@chromium.org>

Gerrit-Reviewer: Nikolaos Papaspyrou <niko...@chromium.org>

Gerrit-Reviewer: Olivier Flückiger <ol...@chromium.org>

Gerrit-Reviewer: v8-s...@luci-project-accounts.iam.gserviceaccount.com <v8-s...@luci-project-accounts.iam.gserviceaccount.com>