Fix align spacing

luamml-amsmath.lua

@@ -70,7 +70,7 @@ lua.get_functions_table()[funcid] = function()
   if not mml_table then return end
   local columns = node.count(node.id'align_record', tex.lists.align_head)//2
   mml_table.columnalign = string.rep('right left', columns, ' ')
-  mml_table.columnalign = string.rep('0.3em', columns, '0.8em ') -- FIXME: 0.3em is a hack needed since MathML doesn't add spacing for our empty mrow
+  mml_table.columnspacing = string.rep('0', columns, ' 0.8em ') -- FIXME: 0.3em is a hack needed since MathML doesn't add spacing for our empty mrow
   save_result(mml_table, 0)
 end
 

luamml-convert.lua

@@ -376,10 +376,15 @@ function nodes_to_table(head, cur_style)
     end
     nonscript = nil
     if core and new_core ~= space_like then
-      core = new_core
+      core = core == space_like and new_core or nil
     end
     mn = new_mn
   end
+  -- In TeX, groups are never space like
+  if core == space_like then
+    core = {[0] = 'mi', intent = '@ignore'}
+    result[#result+1] = core
+  end
   if t[0] == 'mrow' and #t == 1 then
     assert(t == result)
     result = t[1]

test_tex.tex

@@ -25,7 +25,7 @@
 \]
 
 \begin{align}
-  abc&=def\\
+  abc&=def & e^{\mathrm{i}\pi}&=-1\\
   1+2&=3\\
   5
 \end{align}