Add root accessor to Block and move access to ModuleBlock attrs to use root.

compiler/block.py

@@ -56,17 +56,9 @@ class Block(object):
 
   __metaclass__ = abc.ABCMeta
 
-  # These are ModuleBlock attributes. Avoid pylint errors for accessing them on
-  # Block objects by defining them here.
-  _filename = None
-  _full_package_name = None
-  _buffer = None
-  _strings = None
-  imports = None
-  _future_features = None
-
-  def __init__(self, parent_block, name):
-    self.parent_block = parent_block
+  def __init__(self, parent, name):
+    self.root = parent.root if parent else self
+    self.parent = parent
     self.name = name
     self.free_temps = set()
     self.used_temps = set()
@@ -76,33 +68,6 @@ class Block(object):
     self.loop_stack = []
     self.is_generator = False
 
-    block = self
-    while block and not isinstance(block, ModuleBlock):
-      block = block.parent_block
-    self._module_block = block
-
-  @property
-  def full_package_name(self):
-    # pylint: disable=protected-access
-    return self._module_block._full_package_name
-
-  @property
-  def filename(self):
-    return self._module_block._filename  # pylint: disable=protected-access
-
-  @property
-  def buffer(self):
-    return self._module_block._buffer  # pylint: disable=protected-access
-
-  @property
-  def strings(self):
-    return self._module_block._strings  # pylint: disable=protected-access
-
-  @property
-  def future_features(self):
-    # pylint: disable=protected-access
-    return self._module_block._future_features
-
   @abc.abstractmethod
   def bind_var(self, writer, name, value):
     """Writes Go statements for assigning value to named var in this block.
@@ -153,10 +118,10 @@ class Block(object):
     alias = None
     if name == 'grumpy':
       alias = 'πg'
-    if name in self._module_block.imports:
-      return self._module_block.imports[name]
+    if name in self.root.imports:
+      return self.root.imports[name]
     package = Package(name, alias)
-    self._module_block.imports[name] = package
+    self.root.imports[name] = package
     return package
 
   def genlabel(self, is_checkpoint=False):
@@ -197,7 +162,7 @@ class Block(object):
   def intern(self, s):
     if len(s) > 64 or _non_word_re.search(s):
       return 'πg.NewStr({})'.format(util.go_str(s))
-    self.strings.add(s)
+    self.root.strings.add(s)
     return 'ß' + s
 
   def _resolve_global(self, writer, name):
@@ -216,12 +181,12 @@ class ModuleBlock(Block):
 
   def __init__(self, full_package_name, filename, src, future_features):
     Block.__init__(self, None, '<module>')
-    self._full_package_name = full_package_name
-    self._filename = filename
-    self._buffer = source.Buffer(src)
-    self._strings = set()
+    self.full_package_name = full_package_name
+    self.filename = filename
+    self.buffer = source.Buffer(src)
+    self.strings = set()
     self.imports = {}
-    self._future_features = future_features
+    self.future_features = future_features
 
   def bind_var(self, writer, name, value):
     writer.write_checked_call1(
@@ -239,19 +204,19 @@ class ModuleBlock(Block):
 class ClassBlock(Block):
   """Python block for a class definition."""
 
-  def __init__(self, parent_block, name, global_vars):
-    Block.__init__(self, parent_block, name)
+  def __init__(self, parent, name, global_vars):
+    Block.__init__(self, parent, name)
     self.global_vars = global_vars
 
   def bind_var(self, writer, name, value):
     if name in self.global_vars:
-      return self._module_block.bind_var(writer, name, value)
+      return self.root.bind_var(writer, name, value)
     writer.write_checked_call1('πClass.SetItem(πF, {}.ToObject(), {})',
                                self.intern(name), value)
 
   def del_var(self, writer, name):
     if name in self.global_vars:
-      return self._module_block.del_var(writer, name)
+      return self.root.del_var(writer, name)
     writer.write_checked_call1('πg.DelVar(πF, πClass, {})', self.intern(name))
 
   def resolve_name(self, writer, name):
@@ -260,7 +225,7 @@ class ClassBlock(Block):
       # Only look for a local in an outer block when name hasn't been declared
       # global in this block. If it has been declared global then we fallback
       # straight to the global dict.
-      block = self.parent_block
+      block = self.parent
       while not isinstance(block, ModuleBlock):
         if isinstance(block, FunctionBlock) and name in block.vars:
           var = block.vars[name]
@@ -268,7 +233,7 @@ class ClassBlock(Block):
             local = util.adjust_local_name(name)
           # When it is declared global, prefer it to anything in outer blocks.
           break
-        block = block.parent_block
+        block = block.parent
     result = self.alloc_temp()
     writer.write_checked_call2(
         result, 'πg.ResolveClass(πF, πClass, {}, {})',
@@ -279,15 +244,15 @@ class ClassBlock(Block):
 class FunctionBlock(Block):
   """Python block for a function definition."""
 
-  def __init__(self, parent_block, name, block_vars, is_generator):
-    Block.__init__(self, parent_block, name)
+  def __init__(self, parent, name, block_vars, is_generator):
+    Block.__init__(self, parent, name)
     self.vars = block_vars
-    self.parent_block = parent_block
+    self.parent = parent
     self.is_generator = is_generator
 
   def bind_var(self, writer, name, value):
     if self.vars[name].type == Var.TYPE_GLOBAL:
-      return self._module_block.bind_var(writer, name, value)
+      return self.root.bind_var(writer, name, value)
     writer.write('{} = {}'.format(util.adjust_local_name(name), value))
 
   def del_var(self, writer, name):
@@ -296,7 +261,7 @@ class FunctionBlock(Block):
       raise util.ParseError(
           None, 'cannot delete nonexistent local: {}'.format(name))
     if var.type == Var.TYPE_GLOBAL:
-      return self._module_block.del_var(writer, name)
+      return self.root.del_var(writer, name)
     adjusted_name = util.adjust_local_name(name)
     # Resolve local first to ensure the variable is already bound.
     writer.write_checked_call1('πg.CheckLocal(πF, {}, {})',
@@ -315,7 +280,7 @@ class FunctionBlock(Block):
                                      util.adjust_local_name(name),
                                      util.go_str(name))
           return expr.GeneratedLocalVar(name)
-      block = block.parent_block
+      block = block.parent
     return self._resolve_global(writer, name)
 
 

compiler/expr_visitor.py

@@ -458,7 +458,7 @@ class ExprVisitor(algorithm.Visitor):
           '$flags, func(πF *πg.Frame, πArgs []*πg.Object) '
           '(*πg.Object, *πg.BaseException) {',
           result=result.name, name=util.go_str(node.name),
-          filename=util.go_str(self.block.filename), args=func_args.expr,
+          filename=util.go_str(self.block.root.filename), args=func_args.expr,
           flags=' | '.join(flags) if flags else 0)
       with self.writer.indent_block():
         for var in func_block.vars.values():

compiler/stmt.py

@@ -140,7 +140,7 @@ class StatementVisitor(algorithm.Visitor):
 
   def __init__(self, block_):
     self.block = block_
-    self.future_features = self.block.future_features or FutureFeatures()
+    self.future_features = self.block.root.future_features or FutureFeatures()
     self.writer = util.Writer()
     self.expr_visitor = expr_visitor.ExprVisitor(self.block, self.writer)
 
@@ -220,7 +220,7 @@ class StatementVisitor(algorithm.Visitor):
           \tπClass := $cls
           \t_ = πClass""")
       self.writer.write_tmpl(tmpl, name=util.go_str(node.name),
-                             filename=util.go_str(self.block.filename),
+                             filename=util.go_str(self.block.root.filename),
                              cls=cls.expr)
       with self.writer.indent_block():
         self.writer.write_temp_decls(body_visitor.block)
@@ -694,7 +694,7 @@ class StatementVisitor(algorithm.Visitor):
     code_objs = []
     for i in xrange(len(parts)):
       package_name = '/'.join(parts[:i + 1])
-      if package_name != self.block.full_package_name:
+      if package_name != self.block.root.full_package_name:
         package = self.block.add_import(package_name)
         code_objs.append('{}.Code'.format(package.alias))
       else:
@@ -816,6 +816,6 @@ class StatementVisitor(algorithm.Visitor):
 
   def _write_py_context(self, lineno):
     if lineno:
-      line = self.block.buffer.source_line(lineno).strip()
+      line = self.block.root.buffer.source_line(lineno).strip()
       self.writer.write('// line {}: {}'.format(lineno, line))
       self.writer.write('πF.SetLineno({})'.format(lineno))