Advanced Data Display
Wing handles debug data conservatively to avoid invoking code that might cause unexpected changes in debug program state, hanging, crashing, thread deadlocks, and other problems that can occur if the debugger exercises code in a way that it was not designed to handle. Some advanced options are provided on the Debugger > Introspection preferences page, to allow Wing to inspect data more deeply:
- Resolve Properties enables calling fget() on properties so that properties can be shown in the Stack Data tool. This is off by default since calling property methods may changed program state unexpectedly, cause threading deadlocks, and bring out bugs in properties code not seen during regular execution.
- Allow Calls in Data Inspection enables calling user-defined __len__, __getitem__, __call__ and similar special methods during data inspection. By default, Wing only calls these if implemented in C code, as for Python's standard data structures.
- Call Python __repr__ Methods enables calling __repr__ even if it is implemented in Python. This is enabled by default, since it is usually safe, but may be disabled for cases where these calls cause problems. Known cases where this option must be disabled include SQL database implementations that include all of very large query results in the repr.
- Inspect Base Classes controls whether Wing will try to inspect base classes for class attributes. This is enabled by default, since it is usually safe, but may be disabled for cases where it causes problems. Known cases where this option must be disabled include openerp and odoo, since they crash on inspection of some base classes.
When any of these options cause errors in the debugger, Wing will try to continue inspection of other data values whenever possible and mark the offending values with <error handling value>. However, if the inspection causes the debug process to crash or deadlock, Wing will fail to identify which value caused the problem, and the debug session will end.
If you are having problems with the debug process crashing unexpectedly while paused in Wing's debugger, try disabling all of the above options and then reenabling those that you need one at a time.
More information can be obtained about failures caused by these options by enabling additional debugger logging with the Debugger > Diagnostics > Debug Internals Log File preference.
