1 files changed, 77 insertions, 0 deletions
diff --git a/testing/web-platform/tests/css/css-animations/display-interpolation.html b/testing/web-platform/tests/css/css-animations/display-interpolation.html
new file mode 100644
index 0000000000..791e794c70
--- /dev/null
+++ b/testing/web-platform/tests/css/css-animations/display-interpolation.html
@@ -0,0 +1,77 @@
+<!DOCTYPE html>
+<link rel=author href="mailto:jarhar@chromium.org">
+<link rel=help href="https://github.com/w3c/csswg-drafts/issues/6429">
+<script src="/resources/testharness.js"></script>
+<script src="/resources/testharnessreport.js"></script>
+<script src="/css/support/interpolation-testcommon.js"></script>
+
+<body>
+<script>
+const alwaysBlock = [
+  {at: -1, expect: 'block'},
+  {at: 0, expect: 'block'},
+  {at: 0.1, expect: 'block'},
+  {at: 0.9, expect: 'block'},
+  {at: 1, expect: 'block'},
+  {at: 1.5, expect: 'block'},
+];
+const alwaysNone = [
+  {at: -1, expect: 'none'},
+  {at: 0, expect: 'none'},
+  {at: 0.1, expect: 'none'},
+  {at: 0.9, expect: 'none'},
+  {at: 1, expect: 'none'},
+  {at: 1.5, expect: 'none'},
+];
+
+test_interpolation({
+  property: 'display',
+  from: 'block',
+  to: 'none',
+  // transition:all is not supposed to allow display to be transitioned.
+  'CSS Transitions with transition: all': alwaysNone
+}, [
+  {at: -1, expect: 'block'},
+  {at: 0, expect: 'block'},
+  {at: 0.1, expect: 'block'},
+  {at: 0.9, expect: 'block'},
+  {at: 1, expect: 'none'},
+  {at: 1.5, expect: 'none'},
+]);
+
+// This transitions tests expect 'block' at every point because transitioning
+// from display:none does not provide an initial style. This is expected and
+// can be worked around by using @initial.
+test_interpolation({
+  property: 'display',
+  from: 'none',
+  to: 'block',
+  'CSS Transitions with transition: all': alwaysBlock,
+  'CSS Transitions': alwaysBlock
+}, [
+  {at: -1, expect: 'none'},
+  {at: 0, expect: 'none'},
+  {at: 0.1, expect: 'block'},
+  {at: 0.9, expect: 'block'},
+  {at: 1, expect: 'block'},
+  {at: 1.5, expect: 'block'},
+]);
+
+test_no_interpolation({
+  property: 'display',
+  from: 'inline',
+  to: 'block'
+});
+
+test_interpolation({
+  property: 'display',
+  from: 'block',
+  to: 'block'
+}, alwaysBlock);
+
+test_interpolation({
+  property: 'display',
+  from: 'none',
+  to: 'none'
+}, alwaysNone);
+</script>