mojom: Add associative arrays to the mojom language.

mojo/public/tools/bindings/generators/cpp_templates/struct_macros.tmpl

Index: mojo/public/tools/bindings/generators/cpp_templates/struct_macros.tmpl
diff --git a/mojo/public/tools/bindings/generators/cpp_templates/struct_macros.tmpl b/mojo/public/tools/bindings/generators/cpp_templates/struct_macros.tmpl
index 0e5119323996ee8044a009aaa3eaaccd1c5fb21b..4182c625535e0d113fb4de17854185e93f97bb77 100644
--- a/mojo/public/tools/bindings/generators/cpp_templates/struct_macros.tmpl
+++ b/mojo/public/tools/bindings/generators/cpp_templates/struct_macros.tmpl
@@ -1,73 +1,85 @@
-{%- macro validate(struct, class_name) %}
-  if (!data)
-    return true;
-
-  if (!ValidateStructHeader(
-          data, sizeof({{class_name}}),
-          {{struct.packed.packed_fields|length}}, bounds_checker)) {
-    return false;
-  }
-
-  const {{class_name}}* MOJO_ALLOW_UNUSED object =
-      static_cast<const {{class_name}}*>(data);
-
-{%-   for packed_field in struct.packed.packed_fields %}
-{%-     set name = packed_field.field.name %}
-{%-     set kind = packed_field.field.kind %}
-{%-     if kind|is_object_kind %}
-{%-       set wrapper_type = kind|cpp_wrapper_type %}
-{%-       if not kind|is_nullable_kind %}
+{%- macro validate_field(struct, name, kind) %}
+{%-   if kind|is_map_kind %}
+{%-     set name_keys = name + "_keys" %}
+{%-     set name_values = name + "_values" %}
+{{ validate_field(struct, name_keys, kind.key_kind) }}
+{{ validate_field(struct, name_values, kind.value_kind) }}
+{%-   elif kind|is_object_kind %}
+{%-     set wrapper_type = kind|cpp_wrapper_type %}
+{%-     if not kind|is_nullable_kind %}
   if (!object->{{name}}.offset) {
     ReportValidationError(
         mojo::internal::VALIDATION_ERROR_UNEXPECTED_NULL_POINTER,
         "null {{name}} field in {{struct.name}} struct");
     return false;
   }
-{%-       endif %}
+{%-     endif %}
   if (!mojo::internal::ValidateEncodedPointer(&object->{{name}}.offset)) {
     ReportValidationError(mojo::internal::VALIDATION_ERROR_ILLEGAL_POINTER);
     return false;
   }
-{%-       if kind|is_any_array_kind or kind|is_string_kind %}
+{%-     if kind|is_any_array_kind or kind|is_string_kind %}
   if (!{{wrapper_type}}::Data_::Validate<
           {{kind|get_array_validate_params|indent(10)}}>(
               mojo::internal::DecodePointerRaw(&object->{{name}}.offset),
               bounds_checker)) {
-{%-       else %}
+{%-     else %}
   if (!{{wrapper_type}}::Data_::Validate(
           mojo::internal::DecodePointerRaw(&object->{{name}}.offset),
           bounds_checker)) {
-{%-       endif %}
+{%-     endif %}
     return false;
   }
-{%-     elif kind|is_any_handle_kind %}
-{%-       if not kind|is_nullable_kind %}
+{%-   elif kind|is_any_handle_kind %}
+{%-     if not kind|is_nullable_kind %}
   if (object->{{name}}.value() == mojo::internal::kEncodedInvalidHandleValue) {
     ReportValidationError(
         mojo::internal::VALIDATION_ERROR_UNEXPECTED_INVALID_HANDLE,
         "invalid {{name}} field in {{struct.name}} struct");
     return false;
   }
-{%-       endif %}
+{%-     endif %}
   if (!bounds_checker->ClaimHandle(object->{{name}})) {
     ReportValidationError(mojo::internal::VALIDATION_ERROR_ILLEGAL_HANDLE);
     return false;
   }
-{%-     endif %}
+{%-   endif %}
+{%- endmacro -%}
+
+
+{%- macro validate(struct, class_name) %}
+  if (!data)
+    return true;
+
+  if (!ValidateStructHeader(
+          data, sizeof({{class_name}}),
+          {{struct.packed.packed_fields|length}}, bounds_checker)) {
+    return false;
+  }
+
+  const {{class_name}}* MOJO_ALLOW_UNUSED object =
+      static_cast<const {{class_name}}*>(data);
+
+{%-   for packed_field in struct.packed.packed_fields %}
+{%-     set name = packed_field.field.name %}
+{%-     set kind = packed_field.field.kind %}
+{{ validate_field(struct, name, kind) }}
 {%-   endfor %}
 
   return true;
 {%- endmacro %}
 
 {%- macro field_line(field) %}
-{%-   set type = field.kind|cpp_field_type %}
 {%-   set name = field.name -%}
 {%-   if field.kind.spec == 'b' -%}
   uint8_t {{name}} : 1;
 {%-   elif field.kind|is_enum_kind -%}
   int32_t {{name}};
+{%-   elif field.kind|is_map_kind -%}
+  mojo::internal::ArrayPointer<{{field.kind.key_kind|cpp_type}}> {{name}}_keys;
+  mojo::internal::ArrayPointer<{{field.kind.value_kind|cpp_type}}> {{name}}_values;
 {%-   else -%}
-  {{type}} {{name}};
+  {{field.kind|cpp_field_type}} {{name}};
 {%-   endif %}
 {%- endmacro %}
 
@@ -96,7 +108,10 @@
 
 {%- macro encodes(struct) -%}
 {%-   for pf in struct.packed.packed_fields %}
-{%-     if pf.field.kind|is_object_kind %}
+{%-     if pf.field.kind|is_map_kind %}
+mojo::internal::Encode(&{{pf.field.name}}_keys, handles);
+mojo::internal::Encode(&{{pf.field.name}}_values, handles);
+{%-     elif pf.field.kind|is_object_kind %}
 mojo::internal::Encode(&{{pf.field.name}}, handles);
 {%-     elif pf.field.kind|is_any_handle_kind %}
 mojo::internal::EncodeHandle(&{{pf.field.name}}, handles);
@@ -106,7 +121,10 @@ mojo::internal::EncodeHandle(&{{pf.field.name}}, handles);
 
 {%- macro decodes(struct) -%}
 {%-   for pf in struct.packed.packed_fields %}
-{%-     if pf.field.kind|is_object_kind %}
+{%-     if pf.field.kind|is_map_kind %}
+mojo::internal::Decode(&{{pf.field.name}}_keys, handles);
+mojo::internal::Decode(&{{pf.field.name}}_values, handles);
+{%-     elif pf.field.kind|is_object_kind %}
 mojo::internal::Decode(&{{pf.field.name}}, handles);
 {%-     elif pf.field.kind|is_any_handle_kind %}
 mojo::internal::DecodeHandle(&{{pf.field.name}}, handles);