feat(ecmascript): %TypedArray%.prototype.slice #736
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yossydev
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May 25, 2025
yossydev
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- doc: https://tc39.es/ecma262/multipage/indexed-collections.html#sec-%typedarray%.prototype.slice
- ref: %TypedArray%.prototype builtin functions #145
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| .unbind()? | ||
| .bind(gc.nogc()); | ||
| let o = ta_record.object; | ||
| // 3. Let srcArrayLength be TypedArrayLength(taRecord). |
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nitpick: This comment should be inside the slice_typed_array method.
| gc: GcScope<'gc, '_>, | ||
| ) -> JsResult<'gc, Value<'gc>> { | ||
| Err(agent.todo("TypedArray.prototype.slice", gc.into_nogc())) | ||
| let start = arguments_list.get(0); |
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nitpick: Both the get call results and the o = this_value; should have a .bind(gc.nogc()) attached. Here it does not make a difference, but it's better to have them here just so that anyone coming in later and using this method as a template to copy-paste from will have the right "idioms" in place.
| let end = end.scope(agent, gc.nogc()); | ||
| let src_array_length = typed_array_length::<T>(agent, &ta_record, gc.nogc()) as i64; | ||
| // 4. Let relativeStart be ? ToIntegerOrInfinity(start). | ||
| let relative_start = to_integer_or_infinity(agent, start.get(agent), gc.reborrow()).unbind()?; |
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issue: No reason to scope start as it is accessed here directly after. You can just remove the scoping line and change this to use start.unbind():
| let relative_start = to_integer_or_infinity(agent, start.get(agent), gc.reborrow()).unbind()?; | |
| let relative_start = to_integer_or_infinity(agent, start.unbind(), gc.reborrow()).unbind()?; |
| let end = end.bind(gc.nogc()); | ||
| let o = ta_record.object; | ||
| let o = o.scope(agent, gc.nogc()); | ||
| let start = start.scope(agent, gc.nogc()); |
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| let start = start.scope(agent, gc.nogc()); |
| relative_start.into_i64().min(src_array_length) | ||
| }; | ||
| // 8. If end is undefined, let relativeEnd be srcArrayLength; else let relativeEnd be ? ToIntegerOrInfinity(end). | ||
| let end_index = if end.get(agent).is_undefined() { |
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nitpick: You could take end out of the scoping here:
| let end_index = if end.get(agent).is_undefined() { | |
| // SAFETY: end is not shared. | |
| let end = unsafe { end.take(agent) }.bind(gc.nogc()); | |
| let end_index = if end.is_undefined() { |
| src_array_length | ||
| } else { | ||
| let integer_or_infinity = | ||
| to_integer_or_infinity(agent, end.get(agent), gc.reborrow()).unbind()?; |
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| to_integer_or_infinity(agent, end.get(agent), gc.reborrow()).unbind()?; | |
| to_integer_or_infinity(agent, end.unbind(), gc.reborrow()).unbind()?; |
| .unbind()? | ||
| .bind(gc.nogc()); | ||
| // 14. If countBytes > 0, then | ||
| if count_bytes > 0 { |
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nitpick: Could maybe return early if count_bytes == 0 and de-indent the if-branch.
| if is_typed_array_out_of_bounds::<T>(agent, &ta_record, gc.nogc()) { | ||
| return Err(agent.throw_exception_with_static_message( | ||
| ExceptionType::TypeError, | ||
| "Callback is not callable", |
| )); | ||
| }; | ||
| // c. Set endIndex to min(endIndex, TypedArrayLength(taRecord)). | ||
| // let end_index = end_index.min(typed_array_length::<T>(agent, &ta_record, gc.nogc()) as i64); |
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issue: Commented out code. Are these being done inside the with_typed_array_viewable!(a, ...) branch? If so, the comments should be moved there. Otherwise, the code should presumably be actually performed.
