Setting individual shape to outlined text field fails if unit is not set

[shadow-identity]

What is affected?

Component

Description

I need to set a shape of the md-outlined-text-field to have rounded top angles but not rounded bottom ones when active. But it does not work if unit is not specified in css custom property which controls the shape.

Reproduction

I need to set a shape of the md-outlined-text-field to have rounded top angles and not rounded bottom. So I set the default shape and override the bottom corners:

    md-outlined-text-field {
        --md-outlined-text-field-container-shape: 1.7rem;
    }
    md-outlined-text-field:focus {
        --md-outlined-text-field-container-shape-end-start: 0;
        --md-outlined-text-field-container-shape-end-end: 0;
    }

But it results in broken shape of the component: not only the top left corner has the radius of 0, but also the left padding / margin completely disappeared:

Workaround

I found that if I set units explicitly (0px or 0rem) it works.

    md-outlined-text-field:focus {
        --md-outlined-text-field-container-shape-end-start: 0rem;
        --md-outlined-text-field-container-shape-end-end: 0px;
    }

Is this a regression?

No or unsure. This never worked, or I haven't tried before.

Affected versions

Failing on 1.2.0

Browser/OS/Node environment

Firefox 123.0b4 (64-bit) mas OS 14.3 (23D56) node v18.14.0

[asyncLiz]

Hm, I believe we use the value in CSS calc()s, where a unit is required. This may just need to be documented as a caveat that units are required.

[shadow-identity]

AFAIK calc() does not require a unit. We even used it to convert --md- opacity variables (which are unit-less numbers between 0 and 1) into percentage values to use later in color-mix(), because color-mix accepts only percents. We was doing it like this:

--md-filled-icon-button-container-color: color-mix(
                    in srgb,
                    var(--md-sys-color-secondary-container),
                    transparent calc(var(--md-sys-state-hover-state-layer-opacity) * 100%)
                );

where --md-sys-state-hover-state-layer-opacity: 0.07999999821186066; is defined somewhere in material definitions.

[md5login]

AFAIK calc() does not require a unit. We even used it to convert --md- opacity variables (which are unit-less numbers between 0 and 1) into percentage values to use later in color-mix(), because color-mix accepts only percents. We was doing it like this:

--md-filled-icon-button-container-color: color-mix(
                    in srgb,
                    var(--md-sys-color-secondary-container),
                    transparent calc(var(--md-sys-state-hover-state-layer-opacity) * 100%)
                );

where --md-sys-state-hover-state-layer-opacity: 0.07999999821186066; is defined somewhere in material definitions.

calc() doesn't require a unit per spec. Units are required by border-radius, which the calc result goes to. Hence, if units are not provided, the calculated result will be unitless, which is incompatible with the border-radius property.

[shadow-identity]

Defining css custom properties with @property may provide hints to the editor, like

@property --md-filled-icon-button-container-color {
    syntax: "<length>";
    ...
}

But I'm not sure if it will work with external library.