Merge pull request #337 from marrink-lab/error-pragma

[1] Error pragma

polyply/src/top_parser.py

@@ -63,7 +63,8 @@ def __init__(self, topology, cwdir=None):
         }
         self.pragma_actions = {
             '#define': self.parse_define,
-            '#include': self.parse_include
+            '#include': self.parse_include,
+            '#error': self.parse_error,
         }
 
     def dispatch(self, line):
@@ -392,9 +393,30 @@ def _molecule(self, line, lineno=0):
         """
         self.current_itp.append(line)
 
+    def parse_error(self, line, lineno=0):
+        """
+        Parse the #error statement.
+        """
+        if self.current_meta:
+           # In this case the #error is enclosed in an
+           # #ifdef statement. However tag of the #ifdef
+           # has not been defined previously. Thus the
+           # error is not triggered.
+           if self.current_meta["condition"] == "ifdef"\
+              and self.current_meta["tag"] not in self.topology.defines:
+                 return
+           # the #error file is enlosed in an #ifndef
+           # so if tag is defined, we ignore this #error
+           elif self.current_meta["condition"] == "ifndef"\
+              and self.current_meta["tag"] in self.topology.defines:
+                 return
+        # we remove the #error
+        msg = line[7:]
+        raise NotImplementedError(msg)
+
     def parse_define(self, line):
         """
-        Parse define statemetns
+        Parse define statements
         """
         tokens = line.split()
 

polyply/tests/test_top_parser.py

@@ -384,6 +384,55 @@ def test_skip_directives(lines):
                                 "gen-pairs":'no',
                                 "fudgeLJ":1.0,
                                 "fudgeQQ":1.0}
+    @staticmethod
+    @pytest.mark.parametrize('lines', (
+         """
+         #define GMXERROR
+         #ifdef GMXERROR
+         #error "This will raise an error."
+         #endif
+         """,
+         """
+         #error "This will raise an error."
+         """,
+    ))
+    def test_error_parsing(lines):
+        """
+        Test that the #error pragma raises an error.
+        """
+        new_lines = textwrap.dedent(lines)
+        new_lines = new_lines.splitlines()
+        force_field = vermouth.forcefield.ForceField(name='test_ff')
+        top = Topology(force_field, name="test")
+        with pytest.raises(NotImplementedError) as err_info:
+            polyply.src.top_parser.read_topology(new_lines, top)
+        assert str(err_info.value) == "\"This will raise an error.\""
+
+    @staticmethod
+    @pytest.mark.parametrize('lines', (
+         """
+         #define NOERROR
+         #ifdef GMXERROR
+         #error "This will raise an error."
+         #endif
+         """,
+         """
+         #define NOERROR
+         #ifndef NOERROR
+         #error This will raise an error.
+         #endif
+         """,
+    ))
+    def test_error_skipped(lines):
+        """
+        Test that the #error pragma is skipped when not defined.
+        """
+        new_lines = textwrap.dedent(lines)
+        new_lines = new_lines.splitlines()
+        force_field = vermouth.forcefield.ForceField(name='test_ff')
+        top = Topology(force_field, name="test")
+        polyply.src.top_parser.read_topology(new_lines, top)
+        assert top.defines == {'NOERROR': True}
 
 def test_consistency():
     """