Added ToJson to JSON schema compiler.

tools/json_schema_compiler/cc_generator.py

Index: tools/json_schema_compiler/cc_generator.py
diff --git a/tools/json_schema_compiler/cc_generator.py b/tools/json_schema_compiler/cc_generator.py
index 8cea17b588af55ed93f5df205ca5076d9bf6080d..5ca02419eed0b3081a738c93cc0d53924d9ccb45 100644
--- a/tools/json_schema_compiler/cc_generator.py
+++ b/tools/json_schema_compiler/cc_generator.py
@@ -88,7 +88,7 @@ class CCGenerator(object):
       )
     for event in self._namespace.events.values():
       (c.Concat(self._GenerateCreateCallbackArguments(
-          cpp_util.Classname(event.name), event))
+          cpp_util.Classname(event.name), event, True))

[not at google - send to devlin, 2012/07/25 23:28:41]

Boolean arguments should be avoided because they make function calls difficult
to understand without lining up the arguments with the method that's being
called. They're the least self-describing type.

If this were C++ we'd define an enum for this, but Python has named arguments so
use those. This method call would be much easier to understand as

self._GenerateCreateCallbackArguments(
    cpp_util.Classname(event.name), event, generate_to_json=True)

[mitchellwrosen, 2012/07/26 02:01:17]

Done.

         .Append()
       )
     (c.Concat(self._cpp_type_generator.GetNamespaceEnd())
@@ -291,7 +291,7 @@ class CCGenerator(object):
     # Results::Create function
     if function.callback:
       c.Concat(self._GenerateCreateCallbackArguments(
-          "%s::Results" % cpp_namespace, function.callback))
+          "%s::Results" % cpp_namespace, function.callback, False))

[not at google - send to devlin, 2012/07/25 23:28:41]

Named arguments also let you specify a default value, so you could leave out
this change altogether.

[mitchellwrosen, 2012/07/26 02:01:17]

Done.

 
     c.Substitute({'cpp_namespace': cpp_namespace})
 
@@ -679,7 +679,10 @@ class CCGenerator(object):
     )
     return c
 
-  def _GenerateCreateCallbackArguments(self, function_scope, callback):
+  def _GenerateCreateCallbackArguments(self,
+                                       function_scope,
+                                       callback,
+                                       is_event):

[not at google - send to devlin, 2012/07/25 23:28:41]

prefer generate_to_json over is_event.

Also, like I said above, generate_to_json=False here.

[mitchellwrosen, 2012/07/26 02:01:17]

Done.

     """Generate all functions to create Value parameters for a callback.
 
     E.g for function "Bar", generate Bar::Results::Create
@@ -688,6 +691,8 @@ class CCGenerator(object):
     function_scope: the function scope path, e.g. Foo::Bar for the function
     Foo::Bar::Baz().
     callback: the Function object we are creating callback arguments for.
+    is_event: if the Function object is an Event or not. A ToJson method is
+    generated for events.

[not at google - send to devlin, 2012/07/25 23:28:41]

need to update comment.

[mitchellwrosen, 2012/07/26 02:01:17]

Done.

     """
     c = Code()
     params = callback.params
@@ -714,9 +719,22 @@ class CCGenerator(object):
 
       c.Append('return create_results.Pass();')
       c.Eblock('}')
+      if is_event:
+        c.Append()
+        (c.Sblock('std::string %(function_scope)s::'
+                  'ToJson(%(declaration_list)s) {')
+          .Append('scoped_ptr<base::ListValue> create_results = '
+                  'Create(%(param_list)s);')
+          .Append('std::string json;')
+          .Append('base::JSONWriter::Write(create_results.get(), &json);')
+          .Append('return json;')
+        )
+        c.Eblock('}')
+
       c.Substitute({
           'function_scope': function_scope,
-          'declaration_list': ', '.join(declaration_list)
+          'declaration_list': ', '.join(declaration_list),
+          'param_list': ', '.join([param.unix_name for param in param_list])
       })
 
     return c