Issue #644 - Parameters tests

[modules/shaper.git] / src / ParametersPlugin / ParametersPlugin_PyInterp.cpp

diff --git a/src/ParametersPlugin/ParametersPlugin_PyInterp.cpp b/src/ParametersPlugin/ParametersPlugin_PyInterp.cpp
index 61b8cfd3326baf960cb579913b036b652a233aef..021f285527d64c30a06933c345433a28eeff2c68 100644 (file)
--- a/src/ParametersPlugin/ParametersPlugin_PyInterp.cpp
+++ b/src/ParametersPlugin/ParametersPlugin_PyInterp.cpp
@@ -8,6 +8,7 @@
 #include <ParametersPlugin_PyInterp.h>
 
 #include <string>
+#include <stdexcept>
 
 ParametersPlugin_PyInterp::ParametersPlugin_PyInterp()
 : PyInterp_Interp()
@@ -18,6 +19,57 @@ ParametersPlugin_PyInterp::~ParametersPlugin_PyInterp()
 {
 }
 
+const char* aSearchCode =
+  "import ast\n"
+  "class FindName(ast.NodeVisitor):\n"
+  "    def __init__(self, name):\n"
+  "        self.name = name\n"
+  "    def visit_Name(self, node):\n"
+  "        if node.id == self.name:\n"
+  "            positions.append((node.lineno, node.col_offset))\n"
+  "FindName(name).visit(ast.parse(expression))";
+
+std::list<std::pair<int, int> >
+ParametersPlugin_PyInterp::positions(const std::string& theExpression,
+                                     const std::string& theName)
+{
+  PyLockWrapper lck; // Acquire GIL until the end of the method
+
+  std::list<std::pair<int, int> > aResult;
+
+  // prepare a context
+  PyObject* aContext = PyDict_New();
+  PyObject* aBuiltinModule = PyImport_AddModule("__builtin__");
+  PyDict_SetItemString(aContext, "__builtins__", aBuiltinModule);
+
+  // extend aContext with variables 
+  PyDict_SetItemString(aContext, "expression", PyString_FromString(theExpression.c_str()));
+  PyDict_SetItemString(aContext, "name", PyString_FromString(theName.c_str()));
+  PyDict_SetItemString(aContext, "positions", Py_BuildValue("[]"));
+
+  // run the search code
+  PyObject* aExecResult = PyRun_String(aSearchCode, Py_file_input, aContext, aContext);
+  Py_XDECREF(aExecResult);
+
+  // receive results from context
+  PyObject* aPositions = PyDict_GetItemString(aContext, "positions");
+  for (int anIndex = 0; anIndex < PyList_Size(aPositions); ++anIndex) {
+    PyObject* aPosition = PyList_GetItem(aPositions, anIndex);
+    PyObject* aLineNo = PyTuple_GetItem(aPosition, 0);
+    PyObject* aColOffset = PyTuple_GetItem(aPosition, 1);
+
+    aResult.push_back(
+        std::pair<int, int>((int)PyInt_AsLong(aLineNo),
+                            (int)PyInt_AsLong(aColOffset)));
+  }
+
+  // TODO(spo): after this refCount of the variable is not 0. Is there memory leak?
+  Py_DECREF(aContext);
+
+  return aResult;
+}
+
+
 std::list<std::string> ParametersPlugin_PyInterp::compile(const std::string& theExpression)
 {
   PyLockWrapper lck; // Acquire GIL until the end of the method
@@ -68,6 +120,12 @@ void ParametersPlugin_PyInterp::extendLocalContext(const std::list<std::string>&
   }
 }
 
+void ParametersPlugin_PyInterp::clearLocalContext()
+{
+  PyLockWrapper lck;
+  PyDict_Clear(_local_context);
+}
+
 
 double ParametersPlugin_PyInterp::evaluate(const std::string& theExpression, std::string& theError)
 {
@@ -129,7 +187,14 @@ bool ParametersPlugin_PyInterp::initContext()
   }
   _global_context = PyModule_GetDict(m);          // get interpreter global variable context
   Py_INCREF(_global_context);
-  _local_context = _global_context;
+  _local_context = PyDict_New();
+  Py_INCREF(_local_context);
 
   return PyRun_SimpleString("from math import *") == 0;
 }
+
+void ParametersPlugin_PyInterp::closeContext()
+{
+  Py_XDECREF(_local_context);
+  PyInterp_Interp::closeContext();
+}