- more natural xml-representation

DHParser/syntaxtree.py

@@ -530,15 +530,18 @@ class Node(collections.abc.Sized):
             for child in self.children:
                 subtree = child._tree_repr(tab, open_fn, close_fn, data_fn,
                                            density, inline, inline_fn)
-                subtree = [subtree] if inline else subtree.split('\n')
-                content.append((sep + usetab).join(s for s in subtree))
+                if subtree:
+                    subtree = [subtree] if inline else subtree.split('\n')
+                    content.append((sep + usetab).join(s for s in subtree))
             return head + usetab + (sep + usetab).join(content) + tail
 
         res = cast(str, self.result)  # safe, because if there are no children, result is a string
+        if not inline and not head:
+            res = res.strip()
         if density & 1 and res.find('\n') < 0:  # and head[0] == "<":
             # except for XML, add a gap between opening statement and content
             gap = ' ' if not inline and head and head.rstrip()[-1:] != '>' else ''
-            return head.rstrip() + gap + data_fn(self.result) + tail.lstrip()
+            return head.rstrip() + gap + data_fn(res) + tail.lstrip()
         else:
             return head + '\n'.join([usetab + data_fn(s) for s in res.split('\n')]) + tail
 

examples/XML/XMLCompiler.py

@@ -682,7 +682,7 @@ class XMLCompiler(Compiler):
 
     def on_document(self, node):
         self.tree.omit_tags.add('CharData')
-
+        self.tree.inline_tags.update({'to', 'from', 'heading', 'body', 'remark'})
         return self.fallback_compiler(node)
 
     def extract_attributes(self, node_sequence):

test/test_syntaxtree.py

@@ -255,6 +255,20 @@ class TestSerialization:
         tree3 = parse_sxpr('(A `(attr "value") `(attr2 "value2") "B")')
         assert tree.as_sxpr() == tree3.as_sxpr()
 
+    def test_sexpr(self):
+        tree = parse_sxpr('(A (B "C") (D "E"))')
+        s = tree.as_sxpr()
+        assert s == '(A\n  (B\n    "C"\n  )\n  (D\n    "E"\n  )\n)', s
+        tree = parse_sxpr('(A (B (C "D") (E "F")) (G "H"))')
+        s = tree.as_sxpr()
+        assert s == '(A\n  (B\n    (C\n      "D"\n    )\n    (E\n      "F"\n    )' \
+            '\n  )\n  (G\n    "H"\n  )\n)', s
+        tree = parse_sxpr('(A (B (C "D\nX") (E "F")) (G " H \n Y "))')
+        s = tree.as_sxpr()
+        assert s == '(A\n  (B\n    (C\n      "D"\n      "X"\n    )' \
+            '\n    (E\n      "F"\n    )\n  )\n  (G\n    " H "\n    " Y "\n  )\n)', s
+
+
     def test_xml_inlining(self):
         tree = parse_sxpr('(A (B "C") (D "E"))')