1 files changed, 74 insertions, 0 deletions
diff --git a/testing/web-platform/tests/html/webappapis/dynamic-markup-insertion/opening-the-input-stream/quirks.window.js b/testing/web-platform/tests/html/webappapis/dynamic-markup-insertion/opening-the-input-stream/quirks.window.js
new file mode 100644
index 0000000000..0ff0bb9944
--- /dev/null
+++ b/testing/web-platform/tests/html/webappapis/dynamic-markup-insertion/opening-the-input-stream/quirks.window.js
@@ -0,0 +1,74 @@
+test(t => {
+  const frame = document.body.appendChild(document.createElement("iframe"));
+  t.add_cleanup(() => frame.contentDocument.close());
+  assert_equals(frame.contentDocument.compatMode, "BackCompat");
+  frame.contentDocument.open();
+  assert_equals(frame.contentDocument.compatMode, "CSS1Compat");
+  frame.contentDocument.close();
+  assert_equals(frame.contentDocument.compatMode, "BackCompat");
+}, "document.open() sets document to no-quirks mode (write no doctype)");
+
+test(t => {
+  const frame = document.body.appendChild(document.createElement("iframe"));
+  t.add_cleanup(() => frame.contentDocument.close());
+  assert_equals(frame.contentDocument.compatMode, "BackCompat");
+  frame.contentDocument.open();
+  assert_equals(frame.contentDocument.compatMode, "CSS1Compat");
+  frame.contentDocument.write("<!doctype html public");
+  assert_equals(frame.contentDocument.compatMode, "CSS1Compat");
+  frame.contentDocument.write(" \"-//IETF//DTD HTML 3//\"");
+  assert_equals(frame.contentDocument.compatMode, "CSS1Compat");
+  frame.contentDocument.write(">");
+  assert_equals(frame.contentDocument.compatMode, "BackCompat");
+  frame.contentDocument.close();
+  assert_equals(frame.contentDocument.compatMode, "BackCompat");
+}, "document.open() sets document to no-quirks mode (write old doctype)");
+
+test(t => {
+  const frame = document.body.appendChild(document.createElement("iframe"));
+  t.add_cleanup(() => frame.contentDocument.close());
+  assert_equals(frame.contentDocument.compatMode, "BackCompat");
+  frame.contentDocument.open();
+  assert_equals(frame.contentDocument.compatMode, "CSS1Compat");
+  frame.contentDocument.write("<!doctype html");
+  assert_equals(frame.contentDocument.compatMode, "CSS1Compat");
+  frame.contentDocument.write(">");
+  assert_equals(frame.contentDocument.compatMode, "CSS1Compat");
+  frame.contentDocument.close();
+  assert_equals(frame.contentDocument.compatMode, "CSS1Compat");
+}, "document.open() sets document to no-quirks mode (write new doctype)");
+
+// This tests the document.open() call in fact sets the document to no-quirks
+// mode, not limited-quirks mode. It is derived from
+// quirks/blocks-ignore-line-height.html in WPT, as there is no direct way to
+// distinguish between a no-quirks document and a limited-quirks document. It
+// assumes that the user agent passes the linked test, which at the time of
+// writing is all major web browsers.
+test(t => {
+  const frame = document.body.appendChild(document.createElement("iframe"));
+  t.add_cleanup(() => frame.contentDocument.close());
+  assert_equals(frame.contentDocument.compatMode, "BackCompat");
+  frame.contentDocument.open();
+  assert_equals(frame.contentDocument.compatMode, "CSS1Compat");
+
+  // Create the DOM tree manually rather than going through document.write() to
+  // bypass the parser, which resets the document mode.
+  const html = frame.contentDocument.appendChild(frame.contentDocument.createElement("html"));
+  const body = html.appendChild(frame.contentDocument.createElement("body"));
+  assert_equals(frame.contentDocument.body, body);
+  body.innerHTML = `
+    <style>#ref { display:block }</style>
+    <div id=test><font size=1>x</font></div>
+    <font id=ref size=1>x</font>
+    <div id=s_ref>x</div>
+  `;
+  assert_equals(frame.contentDocument.compatMode, "CSS1Compat");
+
+  const idTest = frame.contentDocument.getElementById("test");
+  const idRef = frame.contentDocument.getElementById("ref");
+  const idSRef = frame.contentDocument.getElementById("s_ref");
+  assert_equals(frame.contentWindow.getComputedStyle(idTest).height,
+                frame.contentWindow.getComputedStyle(idSRef).height);
+  assert_not_equals(frame.contentWindow.getComputedStyle(idTest).height,
+                    frame.contentWindow.getComputedStyle(idRef).height);
+}, "document.open() sets document to no-quirks mode, not limited-quirks mode");