def scan(self, asts):
"""Main method to initiate the scanning."""
# First build up list of all possible types for use by the rest
# of the type checking process
for ast in asts:
self._t_env.add_type(ast.children[0].value)
# Next visit the top level nodes - class or interface dcls
for ast in asts:
visit(self, ast)
# If a class implements an interface, check it implements it correctly
self._verify_implementations(asts)
def _add_members(self, symbol, node):
"""For a class or interface symbol, and it's corresponding ast node,
add it's method and field symbols to the class or interface
(methods only for interface) symbol.
"""
dcls = None
try:
dcls = node.children[3].children
except IndexError:
# It's an interface
dcls = node.children[2].children
except AttributeError:
# The class body was empty
return
for dcl in sorted(dcls):
# Sorted causes the field dcls to appear first, so after, the
# parameters can be checked for name clashes
dcl_s = visit(self, dcl)
if dcl_s != None:
if isinstance(dcl_s, MethodSymbol):
symbol.add_method(dcl_s)
elif isinstance(dcl_s, ConstructorSymbol):
symbol.constructor = dcl_s
else:
# It's a field
self._check_field_name(dcl_s)
symbol.add_field(dcl_s)
def _scan_method_array(self, node):
"""Create a method symbol for a method which returns an array
type.
"""
name = node.children[0].value
type_ = self._get_method_node_type(node)
type_ = ArrayType(type_, node.children[2].value)
params = visit(self, node.children[3])
if params == None:
params = []
method_s = MethodSymbol(name, type_, params)
method_s.modifiers = node.modifiers
return method_s
def _visit_constructor_dcl_node(self, node):
"""Creates a constructor symbol in much the same way as regular
methods. The difference is constructors do not have return
types.
"""
name = node.children[0].value
# Create variable symbols for each parameter, and add them to
# the method symbol
params = visit(self, node.children[1])
if params == None:
params = []
constructor_s = ConstructorSymbol(name, params)
constructor_s.modifiers = node.modifiers
return constructor_s
def _scan_method(self, node):
"""Helper method for scan_classes_methods which scans properties of the
method, create a symbol for it, and returns it
"""
name = node.children[0].value
type_ = self._get_method_node_type(node)
# Create variable symbols for each parameter, and add them to
# the method symbol
params = visit(self, node.children[2])
if params == None:
params = []
method_s = MethodSymbol(name, type_, params)
try:
method_s.modifiers = node.modifiers
except AttributeError:
# Abstract methods do not have modifiers
pass
return method_s