1422260 - The defaultValue for HTMLOutputElement is set to "" after reset steps in our implementation

Status: RESOLVED FIXED

(Core :: DOM: Forms, defect, P3)

Description

[John Dai[:jdai]]

+++ This bug was initially created as a follow-up of bug 1419316 comment 3+++

Yeah, I think Reset has similar issue.
And please add some comment why mDefaultValue can't be passed. It is very much non-obvious. Had to look at the mutation observing methods.

Feel free to fix Reset (+ add a test) if needed in a separate bug.

Test: http://software.hixie.ch/utilities/js/live-dom-viewer/saved/5597

Comment 1

[John Dai[:jdai]]

I'm going to start working on this bug.

Comment 2

[John Dai[:jdai]]

The spec[1] mentions about reset for output elements:
The reset algorithm for output elements is to set the element's value mode flag to default and then to set the element's textContent IDL attribute to the value of the element's default value (thus replacing the element's child nodes).

After taking comment 0 as test case, it turns out all the browsers don't fully follow the spec, Chrome(72.0.3626.121) and Safari(12.0.3) don't do as spec said replacing the element's child nodes, Firefox(65.0.1) and Edge(17.17134) don't follow part of spec said set the element's textContent IDL attribute to the value of the element's default value.

[1] https://html.spec.whatwg.org/#the-output-element:concept-form-reset-control

Comment 3

[John Dai[:jdai]]

Here is a spec issue[1] is discussing, since this portion of the spec is going to be changed, I'll wait for the spec finalize then fix in bug 1537689 at once.

[1] https://github.com/whatwg/html/issues/4163

Comment 4

[Hsin-Yi Tsai (she/her) [:hsinyi]]

Assigning to Adam, as he has been looking into this.

Comment 5

[Adam Vandolder [:avandolder]]

Attachment: Bug 1422260 - Prevent default value of output element from being truncated after reset. r?edgar

Comment 6

[Adam Vandolder [:avandolder]]

https://treeherder.mozilla.org/jobs?repo=try&revision=4b7a448c70e6d8c9e3235b9a8ea7e627bf4ff2e3

Comment 7

[Pulsebot]

Pushed by [e-mail]:
https://hg.mozilla.org/integration/autoland/rev/fcb266abcf2d
Prevent default value of output element from being truncated after reset. r=edgar

Comment 8

[Natalia Csoregi [:nataliaCs]]

https://hg.mozilla.org/mozilla-central/rev/fcb266abcf2d