Merge pull request #49 from arpds/fix-function-block-arguments-serial…

…ization

Fixed Function AST serialization for nested functions with no arguments

tests/test_tinycss2.py

@@ -217,6 +217,19 @@ def test_serialize_declarations():
     assert serialize(rules) == source
 
 
+def test_serialize_rules_with_functions():
+    source = '''
+        foo#bar.baz {
+            background: url();
+            color: rgb(0, 0, 0);
+            width: calc(calc());
+            height: calc(calc(calc()));
+        }
+    '''
+    rules = parse_rule_list(source)
+    assert serialize(rules) == source
+
+
 def test_backslash_delim():
     source = '\\\nfoo'
     tokens = parse_component_value_list(source)

tinycss2/ast.py

@@ -694,15 +694,14 @@ def _serialize_to(self, write):
         write(serialize_identifier(self.name))
         write('(')
         _serialize_to(self.arguments, write)
-        if self.arguments:
-            function = self
-            while isinstance(function, FunctionBlock):
-                eof_in_string = (
-                    isinstance(function.arguments[-1], ParseError) and
-                    function.arguments[-1].kind == 'eof-in-string')
-                if eof_in_string:
-                    return
-                function = function.arguments[-1]
+        function = self
+        while isinstance(function, FunctionBlock) and function.arguments:
+            eof_in_string = (
+                isinstance(function.arguments[-1], ParseError) and
+                function.arguments[-1].kind == 'eof-in-string')
+            if eof_in_string:
+                return
+            function = function.arguments[-1]
         write(')')