1 files changed, 42 insertions, 0 deletions
diff --git a/testing/web-platform/tests/html/rendering/widgets/button-layout/shrink-wrap.html b/testing/web-platform/tests/html/rendering/widgets/button-layout/shrink-wrap.html
new file mode 100644
index 0000000000..6d61102608
--- /dev/null
+++ b/testing/web-platform/tests/html/rendering/widgets/button-layout/shrink-wrap.html
@@ -0,0 +1,42 @@
+<!doctype html>
+<title>shrink-wrap button</title>
+<link rel=help href=https://html.spec.whatwg.org/multipage/rendering.html#button-layout>
+<link rel=help href=https://drafts.csswg.org/css2/visudet.html#shrink-to-fit-float>
+<script src=/resources/testharness.js></script>
+<script src=/resources/testharnessreport.js></script>
+<!--
+ minimum preferred width 100px
+ preferred width         250px
+ available width         vary
+-->
+<style>
+div.available-width { border: thin dotted red; margin: 1em 0; padding: 1em 0 }
+button { border: none; margin: 0; padding: 0; background: papayawhip; }
+button > span.minimum-preferred-width { width: 100px }
+button > span { width: 50px; display: inline-block; outline: thin dotted blue }
+</style>
+<div class="available-width" style="width: 50px">
+ <button data-expected="100"><span class="minimum-preferred-width">x</span><span>x</span><span>x</span><span>x</span></button>
+</div>
+
+<div class="available-width" style="width: 200px">
+ <button data-expected="200"><span class="minimum-preferred-width">x</span><span>x</span><span>x</span><span>x</span></button>
+</div>
+
+<div class="available-width" style="width: 300px">
+ <button data-expected="250"><span class="minimum-preferred-width">x</span><span>x</span><span>x</span><span>x</span></button>
+</div>
+
+<script>
+const styles = ['display: block', 'display: inline', 'display: inline-block',
+                'display: list-item', 'display: table', 'display: table-row',
+                'display: table-cell', 'float: left'];
+for (const style of styles) {
+  for (const button of [].slice.call(document.querySelectorAll('button'))) {
+    test(() => {
+      button.setAttribute('style', style);
+      assert_equals(button.clientWidth, parseInt(button.dataset.expected, 10));
+    }, `${style} - available ${button.parentNode.getAttribute('style')}`);
+  }
+}
+</script>