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<!DOCTYPE html>
<html class="reftest-wait">
<meta charset="utf-8">
<title>CSS Reference Case</title>
<link rel="author" title="Daniel Holbert" href="mailto:dholbert@mozilla.com">
<script>
const MARGIN_VALS = [15, 22, 28];
const HORIZ_SIDES = ["left", "right"]; // Used for 'float:*' and 'margin-*'.
const DIRECTION_VALS = ["ltr", "rtl"];
// This comes from .float width + horizontal border and padding:
const FLOAT_MARGIN_BOX_WIDTH = 14;
// This comes from 30 (container) - 14 (float mbox width) - 2 (bfc border):
const AVAIL_WIDTH_NO_WRAPPING = 14;
function newDivWithClassAndParent(className, parent) {
let elem = document.createElement("div");
if (className) {
elem.classList.add(className);
}
parent.appendChild(elem);
return elem;
}
function generateGroup(directionVal, floatVal, marginPropSuffix) {
let group = newDivWithClassAndParent("group", document.body);
group.style.direction = directionVal;
const marginPropName = "margin-" + marginPropSuffix;
for (let v of MARGIN_VALS) {
const isMarginSideFloatSide = (marginPropSuffix == floatVal);
// initial-char comparison to match [l]eft/[l]tr and [r]ight/[r]tl:
const isMarginSideLineStartSide = (marginPropSuffix[0] == directionVal[0]);
const isFloatSideLineStartSide = (floatVal[0] == directionVal[0]);
let container = newDivWithClassAndParent("container", group);
if (!isFloatSideLineStartSide) {
// In the corresponding piece of the testcase, the float is floated to
// the inline-end side (for the given writing-mode). We use a
// "row-reverse" flex container as our mockup for that here.
container.style.flexDirection = "row-reverse";
}
let float = newDivWithClassAndParent("float", container);
let bfc = newDivWithClassAndParent("bfc", container);
// Set the actual margin value that we're testing here, based on which
// case this group is in. See comment in testcase for explanation of the
// three cases.
let marginValToUse;
if (isMarginSideFloatSide) {
// Case (A): in the testcase, the margin simply overlaps the float.
// In our mockup here, they don't actually overlap; so we subtract
// the portion that overlaps in the testcase, which is the float's
// margin-box width:
marginValToUse = v - FLOAT_MARGIN_BOX_WIDTH;
} else if (isMarginSideLineStartSide) {
// Case (B): we push the BFC down below the float (which we emulate
// here with a wrapped flexbox), and we use the full specified margin:
container.style.flexWrap = "wrap";
marginValToUse = v;
} else {
// Case (C): we let the BFC be smooshed against the float, and the
// margin effectively behaves as if it were clamped to the available
// space (so we just clamp it to that value here).
marginValToUse = AVAIL_WIDTH_NO_WRAPPING;
}
bfc.style[marginPropName] = marginValToUse + "px";
}
}
function go() {
for (let directionVal of DIRECTION_VALS) {
for (let floatVal of HORIZ_SIDES) {
for (let marginPropSuffix of HORIZ_SIDES) {
generateGroup(directionVal, floatVal, marginPropSuffix);
}
}
}
// Note: the "reftest-wait" usage here isn't strictly necessary; it just
// helps ensure that we actually make it through all of the above JS and
// populate this document with the content that we want to render.
// (Specifically: if we e.g. throw a JS exception somewhere early in both
// the testcase and reference case, then the "reftest-wait" class will
// never be removed; and that will cause the test run to be classified
// as a failure, rather than a trivial "pass" with a visual comparison of
// two blank documents.)
document.documentElement.removeAttribute("class");
}
</script>
<style>
.group {
width: 300px;
border: 1px solid black;
}
.container {
display: inline-flex;
align-content: start;
vertical-align: top;
width: 30px;
height: 40px;
/* This border and margin are just cosmetic, to avoid overlap between
* adjacent containers within a row. */
border: 1px solid gray;
margin-left: 30px;
}
.float {
width: 7px;
height: 8px;
background: fuchsia;
border: 1px solid purple;
margin: 1px 3px 1px 2px;
}
.bfc {
display: flow-root;
background: aqua;
height: 15px;
border: 1px solid blue;
/* We use "flex: 1" (on a flex item) to mock up the fill-available-space
* block-layout behavior in the testcase. */
flex: 1 auto;
}
</style>
<body onload="go()">
</body>
</html>