diff --git a/DHParser/syntaxtree.py b/DHParser/syntaxtree.py
index da0ffd35958a7e9efbd08772f5e687e4322f8c25..c2ad075f7cad1dd5f26358a0e37a15a2afd31099 100644
--- a/DHParser/syntaxtree.py
+++ b/DHParser/syntaxtree.py
@@ -22,6 +22,8 @@ permissions and limitations under the License.
 import itertools
 import os
 from functools import partial
+
+
 try:
     import regex as re
 except ImportError:
@@ -56,7 +58,19 @@ __all__ = ['WHITESPACE_KEYWORD',
            'assert_content']
 
 
-class ZombieParser:
+class MockParser:
+    def __init__(self, name=''):
+        self.name = name
+
+    def __str__(self):
+        return self.name or self.__class__.__name__
+
+    def __call__(self, text):
+        """Better call Saul ;-)"""
+        return None, text
+
+
+class ZombieParser(MockParser):
     """
     Serves as a substitute for a Parser instance.
 
@@ -69,9 +83,9 @@ class ZombieParser:
     alive = False
 
     def __init__(self):
+        super(ZombieParser, self).__init__("ZOMBIE")
         assert not self.__class__.alive, "There can be only one!"
         assert self.__class__ == ZombieParser, "No derivatives, please!"
-        self.name = "ZOMBIE"
         self.__class__.alive = True
 
     def __copy__(self):
@@ -80,13 +94,6 @@ class ZombieParser:
     def __deepcopy__(self, memo):
         return self
 
-    def __str__(self):
-        return self.name
-
-    def __call__(self, text):
-        """Better call Saul ;-)"""
-        return None, text
-
 
 ZOMBIE_PARSER = ZombieParser()
 
@@ -381,6 +388,48 @@ class Node:
         return nav(path.split('/'))
 
 
+def mock_syntax_tree(sexpr):
+    """Generates a tree of nodes from an S-expression.
+
+    Example: 
+    >>> mock_syntax_tree("(a (b c))").as_sexpr()
+    (a 
+        (b 
+            c 
+        )
+    )
+    """
+    def next_block(s):
+        s = s.strip()
+        while s[0] != ')':
+            assert s[0] == '(', s
+            level = 1;
+            i = 1
+            while level > 0:
+                if s[i] == '(':
+                    level += 1
+                elif s[i] == ')':
+                    level -= 1
+                i += 1
+            yield s[:i]
+            s = s[i:].strip()
+
+    sexpr = sexpr.strip()
+    assert sexpr[0] == '(', sexpr
+    sexpr = sexpr[1:].strip()
+    m = re.match('\w+', sexpr)
+    name = sexpr[:m.end()]
+    sexpr = sexpr[m.end():].strip()
+    if sexpr[0] == '(':
+        result = tuple(mock_syntax_tree(block) for block in next_block(sexpr))
+    else:
+        m = re.match('\w+', sexpr)
+        result = sexpr[:m.end()]
+        sexpr = sexpr[m.end():].strip()
+        assert sexpr[0] == ')', sexpr
+    return Node(MockParser(name), result)
+
+
 ########################################################################
 #
 # syntax tree transformation functions
diff --git a/tests/test_dsl.py b/tests/test_dsl.py
index 896b03a3650280faafdbb0a90dfed1fc72bba0fc..13462f9700cdc6dc3138dd0166c1bc5b10da488c 100644
--- a/tests/test_dsl.py
+++ b/tests/test_dsl.py
@@ -20,4 +20,31 @@ See the License for the specific language governing permissions and
 limitations under the License.
 """
 
+import os
+import sys
+from DHParser.dsl import run_compiler
 
+class TestCompilerGeneration:
+    trivial_lang = """
+        text = { word | WSPC }
+        word = /\w+/
+        WSPC = /\s*/
+        """
+    trivial_text = """Es war ein König in Thule."""
+
+
+    def setup(self):
+
+
+if (not os.path.exists('PopRetrieve_compiler.py') or
+            suite_outdated('PopRetrieve_compiler.py', 'PopRetrieve.ebnf')):
+        print("recompiling PopRetrieve parser")
+        errors = run_compiler("PopRetrieve.ebnf")
+        if errors:
+            print('\n\n'.join(errors))
+            sys.exit(1)
+
+
+if __name__ == "__main__":
+    from run import runner
+    runner("", globals())
\ No newline at end of file
diff --git a/tests/test_syntaxtree.py b/tests/test_syntaxtree.py
index acd080c048ae35480b5fca18bd47983794a12153..c4d6ba3571f306f4de632e6f9eb3adc4ecbef8c8 100644
--- a/tests/test_syntaxtree.py
+++ b/tests/test_syntaxtree.py
@@ -20,14 +20,13 @@ limitations under the License.
 """
 
 import os
-import re
 import sys
 sys.path.append(os.path.abspath('../../'))
 from DHParser.toolkit import compact_sexpr
-from DHParser.syntaxtree import Node, traverse
+from DHParser.syntaxtree import traverse, mock_syntax_tree
 
 
-class DummyParser:
+class MockParser:
     def __init__(self, name=''):
         self.name = name
 
@@ -38,47 +37,6 @@ class DummyParser:
         return None, text
 
 
-def from_sexpr(s):
-    """Generates a tree of nodes from an S-expression.
-    
-    Example: 
-    >>> from_sexpr("(a (b c))").as_sexpr()
-    (a 
-        (b 
-            c 
-        )
-    )
-    """
-    def next_block(s):
-        s = s.strip()
-        while s[0] != ')':
-            assert s[0] == '(', s
-            level = 1;  i = 1
-            while level > 0:
-                if s[i] == '(':
-                    level += 1
-                elif s[i] == ')':
-                    level -= 1
-                i += 1
-            yield s[:i]
-            s = s[i:].strip()
-
-    s = s.strip()
-    assert s[0] == '(', s
-    s = s[1:].strip()
-    m = re.match('\w+', s)
-    name = s[:m.end()]
-    s = s[m.end():].strip()
-    if s[0] == '(':
-        result = tuple(from_sexpr(block) for block in next_block(s))
-    else:
-        m = re.match('\w+', s)
-        result = s[:m.end()]
-        s = s[m.end():].strip()
-        assert s[0] == ')', s
-    return Node(DummyParser(name), result)
-
-
 class TestSExpr:
     """
     Tests for S-expression handling.
@@ -88,7 +46,7 @@ class TestSExpr:
 
     def test_selftest_from_sexpr(self):
         sexpr = '(a (b c) (d e) (f (g h)))'
-        tree = from_sexpr(sexpr)
+        tree = mock_syntax_tree(sexpr)
         assert compact_sexpr(tree.as_sexpr(prettyprint=False)) == sexpr
 
 
@@ -98,9 +56,9 @@ class TestNode:
     """
     def setup(self):
         self.unique_nodes_sexpr = '(a (b c) (d e) (f (g h)))'
-        self.unique_tree = from_sexpr(self.unique_nodes_sexpr)
+        self.unique_tree = mock_syntax_tree(self.unique_nodes_sexpr)
         self.recurring_nodes_sexpr = '(a (b x) (c (d e) (b y)))'
-        self.recurr_tree = from_sexpr(self.recurring_nodes_sexpr)
+        self.recurr_tree = mock_syntax_tree(self.recurring_nodes_sexpr)
 
     def test_str(self):
         assert str(self.unique_tree) == "ceh"
@@ -117,7 +75,7 @@ class TestNode:
 
 class TestErrorHandling:
     def test_error_flag_propagation(self):
-        tree = from_sexpr('(a (b c) (d (e (f (g h)))))')
+        tree = mock_syntax_tree('(a (b c) (d (e (f (g h)))))')
 
         def find_h(node):
             if node.result == "h":