Source code

Revision control

Copy as Markdown

Other Tools

Test Info: Warnings

<!DOCTYPE html>
<script src="/resources/testharness.js"></script>
<script src="/resources/testharnessreport.js"></script>
<style>
textarea {
font-family: monospace;
}
.disable-default {
field-sizing: content;
}
.small-placeholder {
font-size: 32px;
}
.small-placeholder::placeholder {
font-size: 16px;
}
.large-placeholder {
font-size: 20px;
}
.large-placeholder::placeholder {
font-size: 40px;
}
</style>
<body>
<div id="container"></div>
<script>
const DISABLE = 'class="disable-default"';
const LONG_TEXT = 'The quick brown fox jumps over the lazy dog.';
function addElements(source) {
const container = document.querySelector('#container');
container.innerHTML = source + source;
container.lastElementChild.classList.add('disable-default');
return {
fixed: container.firstElementChild,
content: container.lastElementChild
};
}
function addTwoElements(source1, source2) {
const container = document.querySelector('#container');
container.innerHTML = source1 + source2;
return {
e1: container.firstElementChild,
e2: container.lastElementChild
};
}
test(() => {
let pair = addElements('<textarea></textarea>');
// Historically a <textarea> has approximately 20ch x 2lh size by default.
// A <textarea> with field-sizing:content must be samller than the default.
assert_less_than(pair.content.offsetWidth, pair.fixed.offsetWidth);
assert_less_than(pair.content.offsetHeight, pair.fixed.offsetHeight);
pair = addTwoElements(`<textarea ${DISABLE}></textarea>`, `<textarea ${DISABLE}>foo</textarea>`);
assert_less_than(pair.e1.offsetWidth, pair.e2.offsetWidth);
assert_equals(pair.e1.offsetHeight, pair.e2.offsetHeight);
}, 'Empty value');
test(() => {
let pair = addElements('<textarea cols="10" rows="3"></textarea>');
assert_less_than(pair.content.offsetWidth, pair.fixed.offsetWidth);
assert_less_than(pair.content.offsetHeight, pair.fixed.offsetHeight);
}, 'Empty value with cols/rows');
test(() => {
let pair = addElements(`<textarea>${LONG_TEXT}</textarea>`);
assert_greater_than(pair.content.offsetWidth, pair.fixed.offsetWidth);
pair = addElements(`<textarea placeholder="${LONG_TEXT}"></textarea>`);
assert_greater_than(pair.content.offsetWidth, pair.fixed.offsetWidth);
}, 'Auto width and auto height with a long text');
test(() => {
let pair = addElements('<textarea style="width:20ch; height:2lh"></textarea>');
assert_equals(pair.content.offsetWidth, pair.fixed.offsetWidth);
assert_equals(pair.content.offsetHeight, pair.fixed.offsetHeight);
pair = addElements(`<textarea style="width:20ch; height:2lh">${LONG_TEXT}</textarea>`);
assert_equals(pair.content.offsetWidth, pair.fixed.offsetWidth);
assert_equals(pair.content.offsetHeight, pair.fixed.offsetHeight);
pair = addElements(`<textarea style="width:20ch; height:2lh" placeholder="${LONG_TEXT}"></textarea>`);
assert_equals(pair.content.offsetWidth, pair.fixed.offsetWidth);
assert_equals(pair.content.offsetHeight, pair.fixed.offsetHeight);
}, 'Explicit width and heigth');
test(() => {
let pair = addElements('<textarea style="width:20ch"></textarea>');
assert_equals(pair.content.offsetWidth, pair.fixed.offsetWidth);
assert_less_than(pair.content.offsetHeight, pair.fixed.offsetHeight);
pair = addElements(`<textarea style="width:20ch">${LONG_TEXT}</textarea>`);
assert_equals(pair.content.offsetWidth, pair.fixed.offsetWidth);
assert_greater_than(pair.content.offsetHeight, pair.fixed.offsetHeight);
pair = addElements(`<textarea style="width:20ch" placeholder="${LONG_TEXT}"></textarea>`);
assert_equals(pair.content.offsetWidth, pair.fixed.offsetWidth);
assert_greater_than(pair.content.offsetHeight, pair.fixed.offsetHeight);
}, 'Explicit width and auto height');
test(() => {
let pair = addElements('<textarea style="height:2lh"></textarea>');
assert_less_than(pair.content.offsetWidth, pair.fixed.offsetWidth);
assert_equals(pair.content.offsetHeight, pair.fixed.offsetHeight);
pair = addElements(`<textarea style="height:2lh">${LONG_TEXT}</textarea>`);
assert_greater_than(pair.content.offsetWidth, pair.fixed.offsetWidth);
assert_equals(pair.content.offsetHeight, pair.fixed.offsetHeight);
pair = addElements(`<textarea style="height:2lh" placeholder="${LONG_TEXT}"></textarea>`);
assert_greater_than(pair.content.offsetWidth, pair.fixed.offsetWidth);
assert_equals(pair.content.offsetHeight, pair.fixed.offsetHeight);
}, 'Explicit height and auto width');
test(() => {
let pair = addTwoElements(`<textarea class="disable-default small-placeholder"></textarea>`,
`<textarea class="disable-default small-placeholder" placeholder="foo"></textarea>`);
assert_less_than(pair.e1.offsetWidth, pair.e2.offsetWidth);
assert_equals(pair.e1.offsetHeight, pair.e2.offsetHeight);
}, 'Text caret is taller than the placeholder');
test(() => {
let pair = addTwoElements(`<textarea class="disable-default large-placeholder"></textarea>`,
`<textarea class="disable-default large-placeholder" placeholder="foo"></textarea>`);
assert_less_than(pair.e1.offsetWidth, pair.e2.offsetWidth, 'width');
assert_less_than(pair.e1.offsetHeight, pair.e2.offsetHeight, 'height');
}, 'Text caret is shorter than the placeholder');
test(() => {
const container = document.querySelector('#container');
container.innerHTML = '<textarea></textarea>';
const element = container.firstChild;
const w = element.offsetWidth;
const h = element.offsetHeight;
element.classList.add('disable-default');
assert_less_than(element.offsetWidth, w);
assert_less_than(element.offsetHeight, h);
}, 'Update field-sizing property dynamically');
</script>
</body>