Add debugging tools to aid the creation of giwtypes

Issue: #41

README.md

@@ -339,9 +339,15 @@ fields:
    buffer in the interface. Can be very useful if your data structure represents
    transposition with an internal metadata.
 
-The function `is_symbol_observable()` receives a gdb symbol and must only return
-`True` if that symbol is of the observable type (the buffer you are dealing
-with).
+The function `is_symbol_observable()` receives a gdb symbol and a string
+containing the variable name, and must only return `True` if that symbol is of
+the observable type (the buffer you are dealing with).
+
+It is possible to debug your custom inspector methods by using the python
+decorators `@interface.debug_buffer_metadata` and
+`@interface.debug_symbol_observable` in the methods `get_buffer_metadata` and
+`is_symbol_observable`, respectively. This will print information about all
+analyzed symbols in the debugger console every time a breakpoint is hit.
 
 For more information on how to customize this file, check out this [more
 detailed blog post](https://csantosbh.wordpress.com/2016/10/15/configuring-gdb-imagewatch-to-visualize-custom-buffer-types/).

resources/giwscripts/debuggers/gdbbridge.py

@@ -70,7 +70,7 @@ def get_fields_from_type(self, this_type, observable_symbols):
                                                         observable_symbols)
                 observable_symbols.update(type_fields)
             elif ((field_name not in observable_symbols) and
-                  (self._type_bridge.is_symbol_observable(field_val))):
+                  (self._type_bridge.is_symbol_observable(field_val, field_name))):
                 try:
                     observable_symbols.add(field_name)
                 except Exception:
@@ -92,6 +92,7 @@ def get_available_symbols(self):
             for symbol in block:
                 if symbol.is_argument or symbol.is_variable:
                     name = symbol.name
+
                     # Get struct/class fields
                     if name == 'this':
                         # The GDB API is a bit convoluted, so I have to do some
@@ -104,7 +105,7 @@ def get_available_symbols(self):
                             observable_symbols)
                         observable_symbols.update(type_fields)
                     elif ((name not in observable_symbols) and
-                          (self._type_bridge.is_symbol_observable(symbol))):
+                          (self._type_bridge.is_symbol_observable(symbol, name))):
                         try:
                             observable_symbols.add(name)
                         except Exception:

resources/giwscripts/giwtypes/eigen3.py

@@ -99,7 +99,7 @@ def get_buffer_metadata(self, obj_name, picked_obj, debugger_bridge):
             'transpose_buffer': transpose_buffer
         }
 
-    def is_symbol_observable(self, symbol):
+    def is_symbol_observable(self, symbol, symbol_name):
         """
         Returns true if the given symbol is of observable type (the type of the
         buffer you are working with). Make sure to check for pointers of your

resources/giwscripts/giwtypes/interface.py

@@ -8,6 +8,37 @@
 
 import abc
 
+def debug_buffer_metadata(func):
+    def wrapper(self, obj_name, picked_obj, debugger_bridge):
+        try:
+            metadata = func(self, obj_name, picked_obj, debugger_bridge)
+
+            print('[%s] [%s] was parsed by giwtype [%s]' %
+                  (str(picked_obj.type), obj_name, type(self).__name__))
+        except Exception as error:
+            print('[%s] [%s] raised exception when parsed by giwtype [%s]:' %
+                  (str(picked_obj.type), obj_name, type(self).__name__))
+            print('    %s' % str(error))
+
+            raise error
+
+    return wrapper
+
+def debug_symbol_observable(func):
+    def wrapper(self, symbol_obj, symbol_name):
+        is_observable = func(self, symbol_obj, symbol_name)
+
+        if is_observable:
+            is_observable_str = 'is observable'
+        else:
+            is_observable_str = 'is NOT observable'
+
+        print('[' + str(symbol_obj.type) + '] [' + symbol_name + '] ' +
+              is_observable_str + ' by [' + type(self).__name__ + ']')
+
+        return is_observable
+
+    return wrapper
 
 class TypeInspectorInterface():
     """
@@ -41,11 +72,11 @@ def get_buffer_metadata(self, obj_name, picked_obj, debugger_bridge):
         pass
 
     @abc.abstractmethod
-    def is_symbol_observable(self, symbol_obj):
+    def is_symbol_observable(self, symbol_obj, symbol_name):
         """
-        Given the debugger with its internal fields and type symbol_obj, this
-        method must return True if symbol_obj corresponds to an observable
-        variable (i.e. if its type corresponds to the type of the buffers that
-        you want to plot).
+        Given the debugger with its internal fields and type symbol_obj, and
+        its name symbol_name, this method must return True if symbol_obj
+        corresponds to an observable variable (i.e. if its type corresponds to
+        the type of the buffers that you want to plot).
         """
         pass

resources/giwscripts/giwtypes/opencv.py

@@ -66,7 +66,7 @@ def get_buffer_metadata(self, obj_name, picked_obj, debugger_bridge):
             'transpose_buffer' : False
         }
 
-    def is_symbol_observable(self, symbol):
+    def is_symbol_observable(self, symbol, symbol_name):
         """
         Returns true if the given symbol is of observable type (the type of the
         buffer you are working with). Make sure to check for pointers of your
@@ -123,7 +123,7 @@ def get_buffer_metadata(self, obj_name, picked_obj, debugger_bridge):
             'transpose_buffer': False
         }
 
-    def is_symbol_observable(self, symbol):
+    def is_symbol_observable(self, symbol, symbol_name):
         symbol_type = str(symbol.type)
         type_regex = r'(const\s+)?CvMat(\s+?[*&])?'
         return re.match(type_regex, symbol_type) is not None

resources/giwscripts/typebridge.py

@@ -35,20 +35,20 @@ def get_buffer_metadata(self, symbol_name, picked_obj, debugger_bridge):
         purpose of plotting it in the giwwindow
         """
         for module in self._type_inspectors:
-            if module.is_symbol_observable(picked_obj):
+            if module.is_symbol_observable(picked_obj, symbol_name):
                 return module.get_buffer_metadata(symbol_name,
                                                   picked_obj,
                                                   debugger_bridge)
 
         return None
 
-    def is_symbol_observable(self, symbol_obj):
+    def is_symbol_observable(self, symbol_obj, symbol_name):
         """
         Returns true if any available module is able to process this particular
         symbol
         """
         for module in self._type_inspectors:
-            if module.is_symbol_observable(symbol_obj):
+            if module.is_symbol_observable(symbol_obj, symbol_name):
                 return True
 
         return False