testlib use a customized debugger

1 files changed, 140 insertions, 0 deletions

diff --git a/debugger.py b/debugger.py
new file mode 100644
index 0000000..ca7a0c6
--- /dev/null
+++ b/debugger.py
@@ -0,0 +1,140 @@
+"""customized version of pdb's default debugger.
+
+- sets up a history file
+- uses ipython if available to colorize lines of code
+- overrides list command to search for current block instead
+  of using 5 lines of context
+"""
+
+try:
+    import readline
+except ImportError:
+    readline = None
+import os
+import os.path as osp
+import sys
+from pdb import Pdb
+from cStringIO import StringIO
+import inspect
+
+try:
+    from IPython import PyColorize
+except ImportError:
+    def colorize(source, *args):
+        """fallback colorize function"""
+        return source
+else:
+    def colorize(source, start_lineno, curlineno):
+        """"""
+        parser = PyColorize.Parser()
+        output = StringIO()
+        parser.format(source, output)
+        annotated = []
+        for index, line in enumerate(output.getvalue().splitlines()):
+            lineno = index + start_lineno
+            if lineno == curlineno:
+                annotated.append('%4s\t->\t%s' % (lineno, line))
+            else:
+                annotated.append('%4s\t\t%s' % (lineno, line))                
+        return '\n'.join(annotated)
+
+def getsource(obj):
+    """Return the text of the source code for an object.
+
+    The argument may be a module, class, method, function, traceback, frame,
+    or code object.  The source code is returned as a single string.  An
+    IOError is raised if the source code cannot be retrieved."""
+    lines, lnum = inspect.getsourcelines(obj)
+    return ''.join(lines), lnum
+
+
+################################################################
+class Debugger(Pdb):
+    """custom debugger
+    
+    - sets up a history file
+    - uses ipython if available to colorize lines of code
+    - overrides list command to search for current block instead
+      of using 5 lines of context
+    """
+    def __init__(self, tcbk):
+        Pdb.__init__(self)
+        self.reset()
+        while tcbk.tb_next is not None:
+            tcbk = tcbk.tb_next
+        self._tcbk = tcbk
+        self._histfile = osp.join(os.environ["HOME"], ".pdbhist")
+        
+    def setup_history_file(self):
+        """if readline is available, read pdb history file
+        """
+        if readline is not None:
+            try:
+                readline.read_history_file(self._histfile)
+            except IOError:
+                pass
+
+    def start(self):
+        """starts the interactive mode"""
+        self.interaction(self._tcbk.tb_frame, self._tcbk)
+
+    def setup(self, frame, tcbk):
+        """setup hook: set up history file"""
+        self.setup_history_file()
+        Pdb.setup(self, frame, tcbk)
+
+    def set_quit(self):
+        """quit hook: save commands in the history file"""
+        if readline is not None:
+            readline.write_history_file(self._histfile)
+        Pdb.set_quit(self)
+
+
+#     def getvariables(self):
+#         frame = self.curframe
+#         if frame:
+#             print '=======>', frame.f_globals.keys() + frame.f_globals.keys()
+#             return frame.f_globals.keys() + frame.f_globals.keys()
+#         return []
+       
+#     def completenames(self, text, *ignored):
+#         basenames = Pdb.completenames(text, *ignored)
+#         return sorted(basenames + self.getvariables)
+
+#     ## completion
+#     def complete(self, text, state):
+#         """Return the next possible completion for 'text'.
+
+#         If a command has not been entered, then complete against command list.
+#         Otherwise try to call complete_<command> to get list of completions.
+#         """
+#         print '===> completing', text, state
+#         xxx = Pdb.complete(self, text, state)
+#         print 'got', xxx
+#         return xxx
+        
+        
+    ## specific / overidden commands 
+    def do_list(self, arg):
+        """overrides default list command to display the surrounding block
+        instead of 5 lines of context
+        """
+        self.lastcmd = 'list'
+        if not arg:
+            try:
+                source, start_lineno = getsource(self.curframe)
+                print colorize(''.join(source), start_lineno,
+                               self.curframe.f_lineno)
+            except KeyboardInterrupt:
+                pass
+        else:
+            Pdb.do_list(self, arg)
+    do_l = do_list
+        
+
+
+def pm():
+    """use our custom debugger"""
+    dbg = Debugger(sys.last_traceback)
+    dbg.start()
+