Add truth value testing to those lldb Python objects with the IsValid() method definitions.
object.__nonzero__(self) is called to implement truth value testing and the built-in operation bool(),
via a simple delegation to self.IsValid().
Change tests under python_api/lldbutil to utilize this mechanism.
git-svn-id: https://llvm.org/svn/llvm-project/llvdb/trunk@131494 91177308-0d34-0410-b5e6-96231b3b80d8
diff --git a/scripts/Python/modify-python-lldb.py b/scripts/Python/modify-python-lldb.py
index da395c5..5b75789 100644
--- a/scripts/Python/modify-python-lldb.py
+++ b/scripts/Python/modify-python-lldb.py
@@ -34,22 +34,24 @@
'''
-#
# This supports the iteration protocol.
-#
iter_def = " def __iter__(self): return lldb_iter(self, '%s', '%s')"
module_iter = " def module_iter(self): return lldb_iter(self, '%s', '%s')"
breakpoint_iter = " def breakpoint_iter(self): return lldb_iter(self, '%s', '%s')"
-#
+
# Called to implement the built-in function len().
# Eligible objects are those containers with unambiguous iteration support.
-#
len_def = " def __len__(self): return self.%s()"
-#
+
# This supports the rich comparison methods of __eq__ and __ne__.
eq_def = " def __eq__(self, other): return isinstance(other, %s) and %s"
ne_def = " def __ne__(self, other): return not self.__eq__(other)"
+# Called to implement truth value testing and the built-in operation bool();
+# should return False or True, or their integer equivalents 0 or 1.
+# Delegate to self.IsValid() if it is defined for the current lldb object.
+nonzero_def = " def __nonzero__(self): return self.IsValid()"
+
#
# The dictionary defines a mapping from classname to (getsize, getelem) tuple.
#
@@ -109,6 +111,9 @@
# The pattern for recognizing the beginning of the __init__ method definition.
init_pattern = re.compile("^ def __init__\(self, \*args\):")
+# The pattern for recognizing the beginning of the IsValid method definition.
+isvalid_pattern = re.compile("^ def IsValid\(\*args\):")
+
# These define the states of our finite state machine.
NORMAL = 0
DEFINING_ITERATOR = 1
@@ -117,13 +122,32 @@
# The lldb_iter_def only needs to be inserted once.
lldb_iter_defined = False;
+# Our FSM begins its life in the NORMAL state, and transitions to the
+# DEFINING_ITERATOR and/or DEFINING_EQUALITY state whenever it encounters the
+# beginning of certain class definitions, see dictionaries 'd' and 'e' above.
+#
+# Note that the two states DEFINING_ITERATOR and DEFINING_EQUALITY are
+# orthogonal in that our FSM can be in one, the other, or both states at the
+# same time. During such time, the FSM is eagerly searching for the __init__
+# method definition in order to insert the appropriate method(s) into the lldb
+# module.
+#
+# Assuming that SWIG puts out the __init__ method definition before other method
+# definitions, the FSM, while in NORMAL state, also checks the current input for
+# IsValid() definition, and inserts a __nonzero__() method definition to
+# implement truth value testing and the built-in operation bool().
state = NORMAL
for line in content.splitlines():
if state == NORMAL:
match = class_pattern.search(line)
+ # Inserts the lldb_iter() definition before the first class definition.
if not lldb_iter_defined and match:
print >> new_content, lldb_iter_def
lldb_iter_defined = True
+
+ # If we are at the beginning of the class definitions, prepare to
+ # transition to the DEFINING_ITERATOR/DEFINING_EQUALITY state for the
+ # right class names.
if match:
cls = match.group(1)
if cls in d:
@@ -132,6 +156,10 @@
if cls in e:
# Adding support for eq and ne for the matched SB class.
state = (state | DEFINING_EQUALITY)
+ # Look for 'def IsValid(*args):', and once located, add implementation
+ # of truth value testing for objects by delegation.
+ elif isvalid_pattern.search(line):
+ print >> new_content, nonzero_def
elif state > NORMAL:
match = init_pattern.search(line)
if match: