mojom: Add associative arrays to the mojom language.

mojo/public/tools/bindings/pylib/mojom/generate/module.py

 # Copyright 2013 The Chromium Authors. All rights reserved.
 # Use of this source code is governed by a BSD-style license that can be
 # found in the LICENSE file.
 
 # This module's classes provide an interface to mojo modules. Modules are
 # collections of interfaces and structs to be used by mojo ipc clients and
 # servers.
 #
 # A simple interface would be created this way:
 # module = mojom.generate.module.Module('Foo')
@@ skipping 210 matching lines @@
 
   def __init__(self, length=-1, kind=None):
     if kind is not None:
       ReferenceKind.__init__(self, 'a%d:%s' % (length, kind.spec))
     else:
       ReferenceKind.__init__(self)
     self.kind = kind
     self.length = length
 
 
+class Map(ReferenceKind):
+  ReferenceKind.AddSharedProperty('key_kind')
+  ReferenceKind.AddSharedProperty('value_kind')
+
+  def __init__(self, key_kind=None, value_kind=None):
+    if (key_kind is not None and value_kind is not None):
+      ReferenceKind.__init__(self,
+                             'm[' + key_kind.spec + '][' + value_kind.spec +
+                             ']')
+      if IsNullableKind(key_kind):
+        raise Exception("Nullable kinds can not be keys in maps.")
+      if IsStructKind(key_kind):
+        # TODO(erg): It would sometimes be nice if we could key on struct
+        # values. However, what happens if the struct has a handle in it? Or
+        # non-copyable data like an array?
+        raise Exception("Structs can not be keys in maps.")
+      if IsHandleKind(key_kind):
+        raise Exception("Handles can not be keys in maps.")
+    else:
+      ReferenceKind.__init__(self)
+
+    self.key_kind = key_kind
+    self.value_kind = value_kind
+
+
 class InterfaceRequest(ReferenceKind):
   ReferenceKind.AddSharedProperty('kind')
 
   def __init__(self, kind=None):
     if kind is not None:
       ReferenceKind.__init__(self, 'r:' + kind.spec)
     else:
       ReferenceKind.__init__(self)
     self.kind = kind
 
@@ skipping 151 matching lines @@
 
 
 def IsNullableKind(kind):
   return IsReferenceKind(kind) and kind.is_nullable
 
 
 def IsAnyArrayKind(kind):
   return IsArrayKind(kind) or IsFixedArrayKind(kind)
 
 
+def IsMapKind(kind):
+  return isinstance(kind, Map)
+
+
 def IsObjectKind(kind):
-  return IsStructKind(kind) or IsAnyArrayKind(kind) or IsStringKind(kind)
-
+  return (IsStructKind(kind) or IsAnyArrayKind(kind) or IsStringKind(kind) or
+          IsMapKind(kind))
 
 def IsNonInterfaceHandleKind(kind):
   return (IsHandleKind(kind) or
           IsDataPipeConsumerKind(kind) or
           IsDataPipeProducerKind(kind) or
           IsMessagePipeKind(kind) or
           IsSharedBufferKind(kind))
 
 
 def IsAnyHandleKind(kind):
   return (IsNonInterfaceHandleKind(kind) or
           IsInterfaceKind(kind) or
           IsInterfaceRequestKind(kind))
 
 
 def IsMoveOnlyKind(kind):
   return IsObjectKind(kind) or IsAnyHandleKind(kind)
 
 
 def HasCallbacks(interface):
   for method in interface.methods:
     if method.response_parameters != None:
       return True
   return False