Update "undefined" definition in section 6.2.4 Value (within 6.2 Characteristics of States and Properties) #2172

rahimabdi · 2024-04-28T16:47:10Z

Closes #2156
Closes #2177

This PR clarifies ambiguity in the varying behaviors of the undefined value for ARIA states and properties by providing a broader definition of "undefined" in section 6.2.4 Value.

Preview | Diff

spectranaut

I also wonder if we need to make more clear that an "undefined" value does not mean the string "undefined", like you brought up in the meeting today (during new PR triage: https://www.w3.org/2024/05/02-aria-minutes.html#t02). Are you making a separate issue for this specifically? Depending on the solution there, it might affect this PR.

Commenting for now because I haven't made up my mind about whether it's ok to explicitly list the examples, or if we should just point people to the tables, I wonder what the other reviewers think.

spectranaut · 2024-05-02T18:56:00Z

index.html

@@ -10013,7 +10013,7 @@ <h3>Value</h3>
 				<dt id="valuetype_tristate">tristate</dt>
 				<dd>Value representing <code>true</code>, <code>false</code>, <code>mixed</code>, or <code>undefined</code> values. The default value for this value type is <code>undefined</code> unless otherwise specified.</dd>
 				<dt id="valuetype_true-false-undefined">true/false/undefined</dt>
-				<dd>Value representing <code>true</code>, <code>false</code>, or <code>undefined</code> (not applicable). The default value for this value type is <code>undefined</code> unless otherwise specified. For example, an element with <sref>aria-expanded</sref> set to <code>false</code> is not currently expanded; an element with <sref>aria-expanded</sref> set to <code>undefined</code> is not expandable.</dd>
+				<dd>Value representing <code>true</code>, <code>false</code>, or <code>undefined</code> (not applicable). Unless otherwise specified, the default value for this value type is <code>undefined</code>. Note that the value <code>undefined</code> conveys a state- or property-dependent behavior including but not limited to lack of support (e.g., <sref>aria-checked</sref>, <sref>aria-pressed</sref>), equivalence with the value <code>false</code> (e.g., <sref>aria-multiselectable</sref>), behavior determined by the user agent (e.g., <sref>aria-hidden</sref>) or non-applicability (e.g., <sref>aria-selected</sref>).


Wow this really shows how inconsistent we have been with the use of undefined 😅

I wonder if we should include the examples, or leave it at Note that the value undefined conveys a state- or property-dependent behavior, consult the values table of the relevant state or property to understand the meaning of an undefined state or property.

smhigley · 2024-05-02T19:20:14Z

index.html

@@ -10013,7 +10013,7 @@ <h3>Value</h3>
 				<dt id="valuetype_tristate">tristate</dt>
 				<dd>Value representing <code>true</code>, <code>false</code>, <code>mixed</code>, or <code>undefined</code> values. The default value for this value type is <code>undefined</code> unless otherwise specified.</dd>
 				<dt id="valuetype_true-false-undefined">true/false/undefined</dt>
-				<dd>Value representing <code>true</code>, <code>false</code>, or <code>undefined</code> (not applicable). The default value for this value type is <code>undefined</code> unless otherwise specified. For example, an element with <sref>aria-expanded</sref> set to <code>false</code> is not currently expanded; an element with <sref>aria-expanded</sref> set to <code>undefined</code> is not expandable.</dd>
+				<dd>Value representing <code>true</code>, <code>false</code>, or <code>undefined</code> (not applicable). Unless otherwise specified, the default value for this value type is <code>undefined</code>. Note that the value <code>undefined</code> conveys a state- or property-dependent behavior including but not limited to lack of support (e.g., <sref>aria-checked</sref>, <sref>aria-pressed</sref>), equivalence with the value <code>false</code> (e.g., <sref>aria-multiselectable</sref>), behavior determined by the user agent (e.g., <sref>aria-hidden</sref>) or non-applicability (e.g., <sref>aria-selected</sref>).


I think it's actually even more complex than this :/. For example, el.ariaChecked = undefined is going to default to the same as false for most roles, only excluding option and treeitem. I think it may be better to not reference specific attributes here. Even for something like aria-pressed, if HTML ever ends up creating a toggle button element, then aria-pressed being undefined would not mean it is not supported. It might be simpler to stick with only one relatively safe example (e.g. the aria-expanded one in the original text), then clarify that for specific behavior, authors should check the tables for that attribute?

I do also think I agree with Valerie that it'd be helpful to clarify that undefined here refers to the value, which is set by either leaving the attribute off entirely or explicitly setting e.g. element.ariaExpanded = undefined, and is not equivalent to the string "undefined" in e.g. aria-expanded="undefined". What do you think?

I think "undefined" needs to be yanked out of the <code> unless it explicitly means the string value "undefined".

As a user of the spec, this is what I might expect (fake example) so I could make sense of it:

Values include yeah, nah, undefined, or undefined (by setting no value).

@aardrian would it help if this section had a link to the IDL reflection section just after it, in addition to text clarifying that undefined is not the string + the (by setting no value) parenthetical?

It does get weirder, in that while you can explicitly set e.g. el.ariaThing = undefined, getting it returns null 🤷🏻‍♀️

Thank you @aardrian @smhigley. As @spectranaut noted, it's currently ambiguous if the value undefined is the string "undefined" or undefined as in not present (or the value undefined). For example, see Note 2 under aria-hidden:

As of ARIA 1.3, aria-hidden="false" is now synonymous with aria-hidden="undefined".

I'm also observing that attr = "undefined" passes HTML validation (W3C Validator). Is this intended or a bug?

@rahimabdi yeah, I believe that's a pretty straightforward mistake in the spec. I made a test page to output the browser-mapped values when ARIA attributes are set to the string "undefined", not set at all, or set programmatically to undefined: https://jsfiddle.net/pobwvgs9/

I checked it in Chrome, Edge, Safari, and Firefox on macOS and Windows (Safari only on mac), and all of them had different results for the string "undefined". The results for not-defined and programmatic = undefined values are what I'd expect & what matches the spec, while the string "undefined" are not.

My proposal would be that we go through the spec and remove any instances accidentally using string ="undefined", and add the clarification of the string not being the same as the value.

As an aside, I do get an error for ="undefined" in the W3C Validator, maybe they have some bugs in the attributes you tested?

aardrian

Sarah and Valerie hit the points I wanted to hit.

rahimabdi · 2024-05-05T00:36:23Z

Awaiting resolution on #2177 before updating PR with new undefined definition.

For future work on this PR (and to address feedback above):

The definition should probably avoid referencing specific properties/states (or reference just aria-expanded as @smhigley notes)
Should include link to IDL reflection section
Should clarify how undefined is assigned (it sounds like it should be as the value, not the string)

netlify · 2024-07-15T19:55:21Z

✅ Deploy Preview for wai-aria ready!

Name	Link
🔨 Latest commit	`839c476`
🔍 Latest deploy log	https://app.netlify.com/sites/wai-aria/deploys/66958586cfb12c000826e46b
😎 Deploy Preview	https://deploy-preview-2172--wai-aria.netlify.app
📱 Preview on mobile	Toggle QR Code... Use your smartphone camera to open QR code link.

To edit notification comments on pull requests, go to your Netlify site configuration.

…ter entity

rahimabdi · 2024-07-15T20:50:15Z

Almost there!

@smhigley @aardrian you mentioned adding a link to the IDL reflection section (section 10. IDL Interface) although I'm not seeing any immediate relation to undefined assignment. Section 6.3 ARIA Attributes does provide examples of IDL assignment but please let me know which link you prefer I include. Thank you!

smockle · 2024-07-25T18:02:13Z

@rahimabdi Does this PR need to be updated in light of the July 25th ARIA WG meeting discussion?

Update glossary definition of 'undefined' value

48bf370

rahimabdi changed the title ~~Update glossary definition for "undefined"~~ Update "undefined" definition in section 6.2.4 Value (within 6.2 Characteristics of States and Properties) Apr 28, 2024

rahimabdi added the editorial a change to an example, note, spelling, grammar, or is related to publishing or the repo label Apr 28, 2024

spectranaut requested review from spectranaut, aardrian and smhigley May 2, 2024 17:13

spectranaut reviewed May 2, 2024

View reviewed changes

smhigley reviewed May 2, 2024

View reviewed changes

aardrian reviewed May 3, 2024

View reviewed changes

pkra added the spec:aria label Jun 14, 2024

Update undefined definition, add assignment examples

5bce014

Rahim Abdi added 3 commits July 15, 2024 13:14

Merge branch 'main' into rahim/update-undefined-definition

66c640c

Fix string value 'undefined' references, use HTML double quote charac…

4e2775b

…ter entity

Remove extraneous 's'

839c476

jnurthen requested review from aardrian, smhigley, spectranaut and keithamus July 18, 2024 17:25

keithamus requested a review from smockle July 18, 2024 17:25

Provide feedback

Saved searches

Use saved searches to filter your results more quickly

Update "undefined" definition in section 6.2.4 Value (within 6.2 Characteristics of States and Properties) #2172

Update "undefined" definition in section 6.2.4 Value (within 6.2 Characteristics of States and Properties) #2172

rahimabdi commented Apr 28, 2024 •

edited by pr-preview bot

Loading

spectranaut left a comment

spectranaut May 2, 2024

smhigley May 2, 2024 •

edited

Loading

aardrian May 3, 2024

smhigley May 3, 2024 •

edited

Loading

rahimabdi May 4, 2024 •

edited

Loading

smhigley May 10, 2024 •

edited

Loading

aardrian left a comment

rahimabdi commented May 5, 2024 •

edited

Loading

netlify bot commented Jul 15, 2024 •

edited

Loading

rahimabdi commented Jul 15, 2024

smockle commented Jul 25, 2024

Update "undefined" definition in section 6.2.4 Value (within 6.2 Characteristics of States and Properties) #2172

Are you sure you want to change the base?

Update "undefined" definition in section 6.2.4 Value (within 6.2 Characteristics of States and Properties) #2172

Conversation

rahimabdi commented Apr 28, 2024 • edited by pr-preview bot Loading

spectranaut left a comment

Choose a reason for hiding this comment

spectranaut May 2, 2024

Choose a reason for hiding this comment

smhigley May 2, 2024 • edited Loading

Choose a reason for hiding this comment

aardrian May 3, 2024

Choose a reason for hiding this comment

smhigley May 3, 2024 • edited Loading

Choose a reason for hiding this comment

rahimabdi May 4, 2024 • edited Loading

Choose a reason for hiding this comment

smhigley May 10, 2024 • edited Loading

Choose a reason for hiding this comment

aardrian left a comment

Choose a reason for hiding this comment

rahimabdi commented May 5, 2024 • edited Loading

netlify bot commented Jul 15, 2024 • edited Loading

✅ Deploy Preview for wai-aria ready!

rahimabdi commented Jul 15, 2024

smockle commented Jul 25, 2024

rahimabdi commented Apr 28, 2024 •

edited by pr-preview bot

Loading

smhigley May 2, 2024 •

edited

Loading

smhigley May 3, 2024 •

edited

Loading

rahimabdi May 4, 2024 •

edited

Loading

smhigley May 10, 2024 •

edited

Loading

rahimabdi commented May 5, 2024 •

edited

Loading

netlify bot commented Jul 15, 2024 •

edited

Loading