<!DOCTYPE html>
<title>Flex minimum height of image with intrinsic min-height specified</title>
<link rel="author" title="[email protected]" href="mailto:[email protected]" />
<link rel="help" href="https://drafts.csswg.org/css-flexbox/#min-size-auto" />
<link rel="help" href="https://drafts.csswg.org/css-sizing-3/#valdef-width-min-content" />
<link rel="match" href="../reference/ref-filled-green-100px-square-only.html" />
<link rel="bookmark" href="https://crbug.com/1088223">
<meta name="assert" content="Flex uses automatic minimum sizes when item specifies min-height:intrinsic, because that is treated as auto.">
<p>Test passes if there is a filled green square.</p>
<!--
Here's the spec trail why the height of this item is 100px.
1. The column flexbox has height:0, and the item has flex-shrink: 1. So
min-height will determine the item's flexed height.
2. The min-content value of the min-height property is equivalent to the
automatic size, per https://drafts.csswg.org/css-sizing-3/#valdef-width-min-content,
because it's in the item's block dimension. (Blink legacy flex disagrees here)
3. Per https://drafts.csswg.org/css-flexbox/#min-size-auto, the used value of a
main axis automatic minimum size on a flex item that is not a scroll container
is a content-based minimum size.
4. The content-based min size of this item is min(content size suggestion,
specified size suggestion). We ignore transferred size suggestion because
this item has a specified size.
5. content size suggestion = 50px because the stretched width of 100px is sent
through the 2:1 aspect ratio to determine the image's min-content size in the
block axis.
5a. This flex container qualifies for 9.8.3:
If a single-line flex container has a definite cross size, the automatic
preferred outer cross size of any stretched flex items is the flex
container's inner cross size (clamped to the flex item's min and max cross
size) and is considered definite.
So the preferred width of the image is 100px.
5b. The float specified by the min-content calculation from css-sizing 5.1 is
<img src="support/300x150-green.png" style="width: 100px; float: left;" />
This element gets height 50px.
6. specified size suggestion = 100px because that's what's specified.
7. So content-based min size = min(50, 100) = 50px. That becomes its flexed
height (see #1).
8. Then, the item stretches its width to 100px. The item has an aspect ratio,
so does the new width change the height? Not according to
https://drafts.csswg.org/css-flexbox/#algo-stretch, which says "Note that
this step does not affect the main size of the flex item, even if it has an
intrinsic aspect ratio." The height remains 50px.
-->
<div style="height: 50px; width: 100px; background: green;"></div>
<div style="display: flex; flex-direction: column; width:100px; height: 0px;">
<img src="support/300x150-green.png" style="min-height: min-content; height: 100px;" />
</div>
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