Introduce a `PythonExceptionState` class.

This is a helper class which supports a number of
features including exception to string formatting with
backtrace handling and auto-restore of exception state
upon scope exit.

Additionally, unit tests are included to verify the
feature set of the class.

llvm-svn: 252994

1 files changed, 63 insertions, 0 deletions

diff --git a/lldb/source/Plugins/ScriptInterpreter/Python/PythonExceptionState.h b/lldb/source/Plugins/ScriptInterpreter/Python/PythonExceptionState.h
new file mode 100644
index 0000000..854276b
--- /dev/null
+++ b/lldb/source/Plugins/ScriptInterpreter/Python/PythonExceptionState.h
@@ -0,0 +1,63 @@
+//===-- PythonExceptionState.h ----------------------------------*- C++ -*-===//
+//
+//                     The LLVM Compiler Infrastructure
+//
+// This file is distributed under the University of Illinois Open Source
+// License. See LICENSE.TXT for details.
+//
+//===----------------------------------------------------------------------===//
+
+#ifndef LLDB_PLUGINS_SCRIPTINTERPRETER_PYTHON_PYTHONEXCEPTIONSTATE_H
+#define LLDB_PLUGINS_SCRIPTINTERPRETER_PYTHON_PYTHONEXCEPTIONSTATE_H
+
+#include "PythonDataObjects.h"
+
+namespace lldb_private
+{
+
+class PythonExceptionState
+{
+  public:
+    explicit PythonExceptionState(bool restore_on_exit);
+    ~PythonExceptionState();
+
+    void
+    Acquire(bool restore_on_exit);
+
+    void
+    Restore();
+
+    void
+    Discard();
+
+    static bool
+    HasErrorOccurred();
+
+    bool
+    IsError() const;
+
+    PythonObject
+    GetType() const;
+
+    PythonObject
+    GetValue() const;
+
+    PythonObject
+    GetTraceback() const;
+
+    std::string
+    Format() const;
+
+  private:
+    std::string
+    ReadBacktrace() const;
+
+    bool m_restore_on_exit;
+
+    PythonObject m_type;
+    PythonObject m_value;
+    PythonObject m_traceback;
+};
+}
+
+#endif