invalid "int" attribute values not picked up (aria-posinset, aria-level, aria-colindex, aria-colspan, and aria-rowindex)

[schne324]

Expectation: axe raises issue for attribute values less than 1 for the following attributes:

• aria-posinset
• aria-level
• aria-colindex
• aria-colspan
• aria-rowindex

Actual: no issues are raised for the above attributes whose values are less than 1

Motivation: came across <div role="heading" aria-level="0" />

test page: https://xzoqr636po.codesandbox.io/
spec: for each of the above attributes the spec states:

The value for {attr name} is an integer greater than or equal to 1.

related files:

• https://github.com/dequelabs/axe-core/blob/89d18d08ed72ba944dfce71c72d5887f4ca26cc1/lib/commons/aria/validate-attr-value.js
• https://github.com/dequelabs/axe-core/blob/51a18a8048a3edd3312400ce8495a6047fcaaa8d/lib/commons/aria/index.js

axe-core version: 3.1.1
axe-webdriver, extension or other integration version: 3.6.0

[schne324]

I am happy to implement this if this is something everyone agrees should be added 😄

[WilcoFiers]

I think this is a good idea. Feel free to create a PR.

[padmavemulapati]

Verified with the latest axe-core develop branch code:
validated for valid and invalid minValue for the following aria-attributes:

aria-posinset - minValue set as "1" , validated for 0,1
aria-posinset="0"

aria-posinset="1"

aria-level - minValue set as "1" , validated for 0,1
Pass criteria:(aria-level="1"

Fail criteria:(aria-level="0")

When aria-level=-1