Normative: DataView methods should throw for absent byteOffset #604
Conversation
This file contains bidirectional Unicode text that may be interpreted or compiled differently than what appears below. To review, open the file in an editor that reveals hidden Unicode characters.
Learn more about bidirectional Unicode characters
ES2016's [GetViewValue](https://tc39.github.io/ecma262/2016/#sec-getviewvalue) (and the SetViewValue) throws for undefined byteOffset arg, after tc39#410, [it casts to 0 using ToIndex](https://tc39.github.io/ecma262/#sec-getviewvalue) This change throws a TypeError only when the argument is absent. e.g.: `new DataView(buffer, 0).getFloat32()`
|
Additional info: the previous methods throw a RangeError, this patch throw a TypeError for absent arguments, this is before any further evaluation, including the ToNumber(byteOffset), although, this current positioning is observable before the evaluation for the [[DataView]] internal slot |
|
btw, I did a quick check and V8, SM and Safari throws a TypeError, but only after checking the [[DataView]] slot. I used the following jsbin to check: http://jsbin.com/yigifujayo/edit?js,console |
|
After discussing about this internally, I changed my mind and believe the specs are just fine, no need to fix this. |
Sign up for free
to join this conversation on GitHub.
Already have an account?
Sign in to comment
Add this suggestion to a batch that can be applied as a single commit.
This suggestion is invalid because no changes were made to the code.
Suggestions cannot be applied while the pull request is closed.
Suggestions cannot be applied while viewing a subset of changes.
Only one suggestion per line can be applied in a batch.
Add this suggestion to a batch that can be applied as a single commit.
Applying suggestions on deleted lines is not supported.
You must change the existing code in this line in order to create a valid suggestion.
Outdated suggestions cannot be applied.
This suggestion has been applied or marked resolved.
Suggestions cannot be applied from pending reviews.
Suggestions cannot be applied on multi-line comments.
Suggestions cannot be applied while the pull request is queued to merge.
Suggestion cannot be applied right now. Please check back later.
ES2016's GetViewValue (and the SetViewValue) throws for undefined byteOffset arg, after #410, it casts to 0 using ToIndex
This change throws a TypeError only when the argument is absent. e.g.:
new DataView(buffer, 0).getFloat32()The alternative for this change is changing GetViewValue and SetViewValue, but that would also affect when the argument is present as
undefinedand the methods would become slightly different from the normalization introduced with ToIndex.