initial subheader tests

tests/suite/layout/grid/subheaders.typ

@@ -1,3 +1,92 @@
+--- grid-subheaders-basic ---
+#grid(
+  grid.header(
+    [a]
+  ),
+  grid.header(
+    level: 2,
+    [b]
+  ),
+  [c]
+)
+
+--- grid-subheaders-basic-non-consecutive ---
+#grid(
+  grid.header(
+    [a]
+  ),
+  [x],
+  grid.header(
+    level: 2,
+    [b]
+  ),
+  [y],
+)
+
+--- grid-subheaders-basic-replace ---
+#grid(
+  grid.header(
+    [a]
+  ),
+  [x],
+  grid.header(
+    level: 2,
+    [b]
+  ),
+  [y],
+  grid.header(
+    level: 2,
+    [c]
+  ),
+  [z],
+)
+
+--- grid-subheaders-repeat ---
+#set page(height: 8em)
+#grid(
+  grid.header(
+    [a]
+  ),
+  grid.header(
+    level: 2,
+    [b]
+  ),
+  ..([c],) * 10,
+)
+
+--- grid-subheaders-repeat-non-consecutive ---
+#set page(height: 8em)
+#grid(
+  grid.header(
+    [a]
+  ),
+  [x],
+  grid.header(
+    level: 2,
+    [b]
+  ),
+  ..([y],) * 10,
+)
+
+--- grid-subheaders-repeat-replace ---
+#set page(height: 8em)
+#grid(
+  grid.header(
+    [a]
+  ),
+  [x],
+  grid.header(
+    level: 2,
+    [b]
+  ),
+  ..([y],) * 10,
+  grid.header(
+    level: 2,
+    [c]
+  ),
+  ..([z],) * 10,
+)
+
 --- grid-subheaders ---
 #set page(width: auto, height: 12em)
 #let rows(n) = {
@@ -22,3 +111,14 @@
   ),
   ..rows(5)
 )
+
+--- grid-subheaders-alone ---
+#table(
+  table.header(
+    [a]
+  ),
+  table.header(
+    level: 2,
+    [b]
+  ),
+)