libs/python/src/exec.cpp: bug fixes

Ralf W. Grosse-Kunstleve · Ralf W. Grosse-Kunstleve · commit 8d2ca93e989c · 2009-08-18T00:24:54.000Z
Remark:
  operator!() for boost::python::object invokes PyObject_IsTrue()
  and is therefore not equivalent to "is None".
  In this particular case !global or !local returns true for an
  empty dict.
(Changes to libs/python/test/exec.cpp just helped in debugging.)


[SVN r55639]
diff --git a/src/exec.cpp b/src/exec.cpp
@@ -17,14 +17,15 @@ namespace python
 object BOOST_PYTHON_DECL eval(str string, object global, object local)
 {
   // Set suitable default values for global and local dicts.
-  if (!global)
+  object none;
+  if (global.ptr() == none.ptr())
   {
     if (PyObject *g = PyEval_GetGlobals())
       global = object(detail::borrowed_reference(g));
     else
       global = dict();
   }
-  if (!local) local = global;
+  if (local.ptr() == none.ptr()) local = global;
   // should be 'char const *' but older python versions don't use 'const' yet.
   char *s = python::extract<char *>(string);
   PyObject* result = PyRun_String(s, Py_eval_input, global.ptr(), local.ptr());
@@ -35,14 +36,15 @@ object BOOST_PYTHON_DECL eval(str string, object global, object local)
 object BOOST_PYTHON_DECL exec(str string, object global, object local)
 {
   // Set suitable default values for global and local dicts.
-  if (!global)
+  object none;
+  if (global.ptr() == none.ptr())
   {
     if (PyObject *g = PyEval_GetGlobals())
       global = object(detail::borrowed_reference(g));
     else
       global = dict();
   }
-  if (!local) local = global;
+  if (local.ptr() == none.ptr()) local = global;
   // should be 'char const *' but older python versions don't use 'const' yet.
   char *s = python::extract<char *>(string);
   PyObject* result = PyRun_String(s, Py_file_input, global.ptr(), local.ptr());
@@ -53,14 +55,15 @@ object BOOST_PYTHON_DECL exec(str string, object global, object local)
 object BOOST_PYTHON_DECL exec_statement(str string, object global, object local)
 {
   // Set suitable default values for global and local dicts.
-  if (!global)
+  object none;
+  if (global.ptr() == none.ptr())
   {
     if (PyObject *g = PyEval_GetGlobals())
       global = object(detail::borrowed_reference(g));
     else
       global = dict();
   }
-  if (!local) local = global;
+  if (local.ptr() == none.ptr()) local = global;
   // should be 'char const *' but older python versions don't use 'const' yet.
   char *s = python::extract<char *>(string);
   PyObject* result = PyRun_String(s, Py_single_input, global.ptr(), local.ptr());
@@ -74,14 +77,15 @@ object BOOST_PYTHON_DECL exec_statement(str string, object global, object local)
 object BOOST_PYTHON_DECL exec_file(str filename, object global, object local)
 {
   // Set suitable default values for global and local dicts.
-  if (!global)
+  object none;
+  if (global.ptr() == none.ptr())
   {
     if (PyObject *g = PyEval_GetGlobals())
       global = object(detail::borrowed_reference(g));
     else
       global = dict();
   }
-  if (!local) local = global;
+  if (local.ptr() == none.ptr()) local = global;
   // should be 'char const *' but older python versions don't use 'const' yet.
   char *f = python::extract<char *>(filename);
   // Let python open the file to avoid potential binary incompatibilities.
diff --git a/test/exec.cpp b/test/exec.cpp
@@ -108,44 +108,49 @@ void exec_test_error()
   python::object result = python::exec("print unknown \n", global, global);
 }
 
+void check_pyerr(bool pyerr_expected=false)
+{
+  if (PyErr_Occurred())
+  {
+    if (!pyerr_expected) {
+      BOOST_ERROR("Python Error detected");
+      PyErr_Print();
+    }
+    else {
+      PyErr_Clear();
+    }
+  }
+  else
+  {
+    BOOST_ERROR("A C++ exception was thrown  for which "
+                "there was no exception handler registered.");
+  }
+}
+
 int main(int argc, char **argv)
 {
   BOOST_TEST(argc == 2);
   std::string script = argv[1];
   // Initialize the interpreter
   Py_Initialize();
 
-  if (python::handle_exception(eval_test) ||
-      python::handle_exception(exec_test) ||
-      python::handle_exception(boost::bind(exec_file_test, script)))
-  {
-    if (PyErr_Occurred())
-    {
-      BOOST_ERROR("Python Error detected");
-      PyErr_Print();
-    }
-    else
-    {
-        BOOST_ERROR("A C++ exception was thrown  for which "
-                    "there was no exception handler registered.");
-    }
+  if (python::handle_exception(eval_test)) {
+    check_pyerr();
+  }
+  else if(python::handle_exception(exec_test)) {
+    check_pyerr();
+  }
+  else if (python::handle_exception(boost::bind(exec_file_test, script))) {
+    check_pyerr();
   }
   
   if (python::handle_exception(exec_test_error))
   {
-    if (PyErr_Occurred())
-    {
-      PyErr_Print();
-    }
-    else
-    {
-        BOOST_ERROR("A C++ exception was thrown  for which "
-                    "there was no exception handler registered.");
-    }
+    check_pyerr(/*pyerr_expected*/ true);
   }
   else
   {
-      BOOST_ERROR("Python exception expected, but not seen.");
+    BOOST_ERROR("Python exception expected, but not seen.");
   }
   
   // Boost.Python doesn't support Py_Finalize yet.
