def computeStatement(self, constraint_collection):
# This node has many children to handle, pylint: disable=R0912,R0914,R0915
tried = self.getBlockTry()
except_handler = self.getBlockExceptHandler()
break_handler = self.getBlockBreakHandler()
continue_handler = self.getBlockContinueHandler()
return_handler = self.getBlockReturnHandler()
# The tried block must be considered as a branch, if it is not empty
# already.
collection_start = ConstraintCollectionBranch(
parent = constraint_collection,
name = "try start"
)
abort_context = constraint_collection.makeAbortStackContext(
catch_breaks = break_handler is not None,
catch_continues = continue_handler is not None,
catch_returns = return_handler is not None
)
with abort_context:
# As a branch point for the many types of handlers.
result = tried.computeStatementsSequence(
constraint_collection = constraint_collection
)
# We might be done entirely already.
if result is None:
return None, "new_statements", "Removed now empty try statement."
# Might be changed.
if result is not tried:
self.setBlockTry(result)
tried = result
break_collections = constraint_collection.getLoopBreakCollections()
continue_collections = constraint_collection.getLoopContinueCollections()
return_collections = constraint_collection.getFunctionReturnCollections()
tried_may_raise = tried.mayRaiseException(BaseException)
# Exception handling is useless if no exception is to be raised.
# TODO: signal the change.
if not tried_may_raise:
if except_handler is not None:
self.setBlockExceptHandler(None)
except_handler = None
# If tried may raise, even empty exception handler has a meaning to
# ignore that exception.
if tried_may_raise:
collection_exception_handling = ConstraintCollectionBranch(
parent = collection_start,
name = "except handler"
)
collection_exception_handling.degradePartiallyFromTriedCode(tried)
if except_handler is not None:
result = except_handler.computeStatementsSequence(
constraint_collection = collection_exception_handling
)
# Might be changed.
if result is not except_handler:
self.setBlockExceptHandler(result)
except_handler = result
if break_handler is not None:
if not tried.mayBreak():
self.setBlockBreakHandler(None)
break_handler = None
if break_handler is not None:
collection_break = ConstraintCollectionBranch(
parent = collection_start,
name = "break handler"
)
collection_break.mergeMultipleBranches(break_collections)
result = break_handler.computeStatementsSequence(
constraint_collection = collection_break
)
# Might be changed.
if result is not break_handler:
self.setBlockBreakHandler(result)
break_handler = result
if continue_handler is not None:
if not tried.mayContinue():
self.setBlockContinueHandler(None)
continue_handler = None
if continue_handler is not None:
collection_continue = ConstraintCollectionBranch(
parent = collection_start,
name = "continue handler"
)
collection_continue.mergeMultipleBranches(continue_collections)
result = continue_handler.computeStatementsSequence(
constraint_collection = collection_continue
)
# Might be changed.
if result is not continue_handler:
self.setBlockContinueHandler(result)
continue_handler = result
if return_handler is not None:
if not tried.mayReturn():
self.setBlockReturnHandler(None)
return_handler = None
if return_handler is not None:
collection_return = ConstraintCollectionBranch(
parent = collection_start,
name = "return handler"
)
collection_return.mergeMultipleBranches(return_collections)
result = return_handler.computeStatementsSequence(
constraint_collection = collection_return
)
# Might be changed.
if result is not return_handler:
self.setBlockReturnHandler(result)
return_handler = result
if return_handler is not None:
if return_handler.getStatements()[0].isStatementReturn() and \
return_handler.getStatements()[0].getExpression().isExpressionReturnedValueRef():
self.setBlockReturnHandler(None)
return_handler = None
# Merge exception handler only if it is used. Empty means it is not
# aborting, as it swallows the exception.
if tried_may_raise and (
except_handler is None or \
not except_handler.isStatementAborting()
):
constraint_collection.mergeBranches(
collection_yes = collection_exception_handling,
collection_no = None
)
# An empty exception handler means we have to swallow exception.
if not tried_may_raise and \
break_handler is None and \
continue_handler is None and \
return_handler is None:
return tried, "new_statements", "Removed all try handlers."
tried_statements = tried.getStatements()
pre_statements = []
while tried_statements:
tried_statement = tried_statements[0]
if tried_statement.mayRaiseException(BaseException):
break
if break_handler is not None and \
tried_statement.mayBreak():
break
if continue_handler is not None and \
tried_statement.mayContinue():
break
if return_handler is not None and \
tried_statement.mayReturn():
break
pre_statements.append(tried_statement)
tried_statements = list(tried_statements)
del tried_statements[0]
post_statements = []
if except_handler is not None and except_handler.isStatementAborting():
while tried_statements:
tried_statement = tried_statements[-1]
if tried_statement.mayRaiseException(BaseException):
break
if break_handler is not None and \
tried_statement.mayBreak():
break
if continue_handler is not None and \
tried_statement.mayContinue():
break
if return_handler is not None and \
tried_statement.mayReturn():
break
post_statements.insert(0, tried_statement)
tried_statements = list(tried_statements)
del tried_statements[-1]
if pre_statements or post_statements:
assert tried_statements # Should be dealt with already
tried.setStatements(tried_statements)
result = StatementsSequence(
statements = pre_statements + [self] + post_statements,
source_ref = self.getSourceReference()
)
# TODO: We probably don't want to say this for re-formulation ones.
return result, "new_statements", "Reduced scope of tried block."
return self, None, None
def computeStatement(self, constraint_collection):
# This node has many children to handle, pylint: disable=R0912,R0914
tried = self.getBlockTry()
except_handler = self.getBlockExceptHandler()
break_handler = self.getBlockBreakHandler()
continue_handler = self.getBlockContinueHandler()
return_handler = self.getBlockReturnHandler()
# The tried block must be considered as a branch, if it is not empty
# already.
collection_start = ConstraintCollectionBranch(
parent=constraint_collection, name="try start")
abort_context = constraint_collection.makeAbortStackContext(
catch_breaks=break_handler is not None,
catch_continues=continue_handler is not None,
catch_returns=return_handler is not None,
catch_exceptions=True,
)
with abort_context:
# As a branch point for the many types of handlers.
result = tried.computeStatementsSequence(
constraint_collection=constraint_collection)
# We might be done entirely already.
if result is None:
return None, "new_statements", "Removed now empty try statement."
# Might be changed.
if result is not tried:
self.setBlockTry(result)
tried = result
break_collections = constraint_collection.getLoopBreakCollections()
continue_collections = constraint_collection.getLoopContinueCollections(
)
return_collections = constraint_collection.getFunctionReturnCollections(
)
exception_collections = constraint_collection.getExceptionRaiseCollections(
)
tried_may_raise = tried.mayRaiseException(BaseException)
# Exception handling is useless if no exception is to be raised.
# TODO: signal the change.
if not tried_may_raise:
if except_handler is not None:
self.setBlockExceptHandler(None)
except_handler = None
# If tried may raise, even empty exception handler has a meaning to
# ignore that exception.
if tried_may_raise:
collection_exception_handling = ConstraintCollectionBranch(
parent=collection_start, name="except handler")
if not exception_collections:
for statement in tried.getStatements():
if statement.mayRaiseException(BaseException):
assert False, statement.asXmlText()
assert False
collection_exception_handling.mergeMultipleBranches(
exception_collections)
if except_handler is not None:
result = except_handler.computeStatementsSequence(
constraint_collection=collection_exception_handling)
# Might be changed.
if result is not except_handler:
self.setBlockExceptHandler(result)
except_handler = result
if break_handler is not None:
if not tried.mayBreak():
self.setBlockBreakHandler(None)
break_handler = None
if break_handler is not None:
collection_break = ConstraintCollectionBranch(
parent=collection_start, name="break handler")
collection_break.mergeMultipleBranches(break_collections)
result = break_handler.computeStatementsSequence(
constraint_collection=collection_break)
# Might be changed.
if result is not break_handler:
self.setBlockBreakHandler(result)
break_handler = result
if continue_handler is not None:
if not tried.mayContinue():
self.setBlockContinueHandler(None)
continue_handler = None
if continue_handler is not None:
collection_continue = ConstraintCollectionBranch(
parent=collection_start, name="continue handler")
collection_continue.mergeMultipleBranches(continue_collections)
result = continue_handler.computeStatementsSequence(
constraint_collection=collection_continue)
# Might be changed.
if result is not continue_handler:
self.setBlockContinueHandler(result)
continue_handler = result
if return_handler is not None:
if not tried.mayReturn():
self.setBlockReturnHandler(None)
return_handler = None
if return_handler is not None:
collection_return = ConstraintCollectionBranch(
parent=collection_start, name="return handler")
collection_return.mergeMultipleBranches(return_collections)
result = return_handler.computeStatementsSequence(
constraint_collection=collection_return)
# Might be changed.
if result is not return_handler:
self.setBlockReturnHandler(result)
return_handler = result
if return_handler is not None:
if return_handler.getStatements()[0].isStatementReturn() and \
return_handler.getStatements()[0].getExpression().isExpressionReturnedValueRef():
self.setBlockReturnHandler(None)
return_handler = None
# Merge exception handler only if it is used. Empty means it is not
# aborting, as it swallows the exception.
if tried_may_raise and (
except_handler is None or \
not except_handler.isStatementAborting()
):
constraint_collection.mergeBranches(
collection_yes=collection_exception_handling,
collection_no=None)
# An empty exception handler means we have to swallow exception.
if not tried_may_raise and \
break_handler is None and \
continue_handler is None and \
return_handler is None:
return tried, "new_statements", "Removed all try handlers."
tried_statements = tried.getStatements()
pre_statements = []
while tried_statements:
tried_statement = tried_statements[0]
if tried_statement.mayRaiseException(BaseException):
break
if break_handler is not None and \
tried_statement.mayBreak():
break
if continue_handler is not None and \
tried_statement.mayContinue():
break
if return_handler is not None and \
tried_statement.mayReturn():
break
pre_statements.append(tried_statement)
tried_statements = list(tried_statements)
del tried_statements[0]
post_statements = []
if except_handler is not None and except_handler.isStatementAborting():
while tried_statements:
tried_statement = tried_statements[-1]
if tried_statement.mayRaiseException(BaseException):
break
if break_handler is not None and \
tried_statement.mayBreak():
break
if continue_handler is not None and \
tried_statement.mayContinue():
break
if return_handler is not None and \
tried_statement.mayReturn():
break
post_statements.insert(0, tried_statement)
tried_statements = list(tried_statements)
del tried_statements[-1]
if pre_statements or post_statements:
assert tried_statements # Should be dealt with already
tried.setStatements(tried_statements)
result = StatementsSequence(statements=pre_statements + [self] +
post_statements,
source_ref=self.getSourceReference())
def explain():
# TODO: We probably don't want to say this for re-formulation ones.
result = "Reduced scope of tried block."
if pre_statements:
result += " Leading statements at %s." % (','.join(
x.getSourceReference().getAsString() + '/' + str(x)
for x in pre_statements))
if post_statements:
result += " Trailing statements at %s." % (','.join(
x.getSourceReference().getAsString() + '/' + str(x)
for x in post_statements))
return result
return (result, "new_statements", explain)
return self, None, None
