[mojo][JS][lite] Fix nested enums

This change exports a 'lite_closure_type' filter and modifies the
corresponding function to put an underscore instead of a dot for nested
enums. This new filter is now used in the enum template.

Bug: 939078
Change-Id: I0c4c1a7b08b6df09d460350a22f5b8cbcf318bc8
Reviewed-on: https://chromium-review.googlesource.com/c/chromium/src/+/1538707
Commit-Queue: Oksana Zhuravlova <oksamyt@chromium.org>
Reviewed-by: Ken Rockot <rockot@google.com>
Cr-Commit-Position: refs/heads/master@{#644678}

mojo/public/js/test/module_a.test-mojom

@@ -11,6 +11,25 @@ struct TestStructA1 {
 };
 
 struct TestStructA2 {
+  enum NestedEnum {
+    A,
+    B,
+  };
+
   TestStructA1 ax;
   TestStructA1 ay;
+  NestedEnum enumField;
+};
+
+enum ModuleEnum {
+  THIRD,
+};
+
+interface ParentInterface {
+  enum NestedEnum {
+    FIRST,
+    SECOND,
+  };
+
+  SomeMethod(NestedEnum value);
 };

mojo/public/tools/bindings/generators/js_templates/lite/enum_definition.tmpl

@@ -2,8 +2,10 @@
 {# TODO: Less generic enum annotations would be nice. We do it this way because
    the bindings generator is still too stupid to generate the right integral
    constants directly. #}
+{%- set enum_name = enum|lite_closure_type -%}
+
 {%  if generate_closure_exports -%}
-goog.provide('{{enum_spec_parent}}.{{enum.name}}');
+goog.provide('{{enum_name}}');
 goog.provide('{{enum_spec_parent}}.{{enum.name}}Spec');
 {%- endif %}
 /**
@@ -16,7 +18,7 @@ goog.provide('{{enum_spec_parent}}.{{enum.name}}Spec');
  * @enum {number}
  * @export
  */
-{{enum_parent}}.{{enum.name}} = {
+{{enum_name}} = {
   {# Set up the enum here, but fill out the values later. #}
 {%-   for field in enum.fields %}
   {{field.name}}: 0,
@@ -32,11 +34,11 @@ goog.provide('{{enum_spec_parent}}.{{enum.name}}Spec');
 {# Suppress type checks since we're assigning number into an enum. #}
 /** @suppress {checkTypes} */
 {%-     if field.value %}
-{{enum_parent}}.{{enum.name}}.{{field.name}} = {{field.value|expression_to_text_lite}};
+{{enum_name}}.{{field.name}} = {{field.value|expression_to_text_lite}};
 {%-     elif loop.first %}
-{{enum_parent}}.{{enum.name}}.{{field.name}} = 0;
+{{enum_name}}.{{field.name}} = 0;
 {%-     else %}
-{{enum_parent}}.{{enum.name}}.{{field.name}} = {{enum_parent}}.{{enum.name}}.{{enum.fields[loop.index0 - 1].name}} + 1;
+{{enum_name}}.{{field.name}} = {{enum_name}}.{{enum.fields[loop.index0 - 1].name}} + 1;
 {%-     endif %}
 {%-   endfor %}
 

mojo/public/tools/bindings/generators/mojom_js_generator.py

@@ -306,6 +306,7 @@ class Generator(generator.Generator):
       "namespace_declarations": self._NamespaceDeclarations,
       "closure_type_with_nullability": self._ClosureTypeWithNullability,
       "lite_closure_param_type": self._LiteClosureParamType,
+      "lite_closure_type": self._LiteClosureType,
       "lite_closure_type_with_nullability":
           self._LiteClosureTypeWithNullability,
       "lite_closure_field_type": self._LiteClosureFieldType,
@@ -442,6 +443,11 @@ class Generator(generator.Generator):
       name.append(named_kind.module.namespace)
     if named_kind.parent_kind:
       name.append(named_kind.parent_kind.name)
+
+    if mojom.IsEnumKind(kind) and named_kind.parent_kind:
+      name = ".".join(name)
+      name += "_" + named_kind.name
+    else:
       name.append("" + named_kind.name)
       name = ".".join(name)