JavaScript bindings for Mojo message validation

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

Index: mojo/public/tools/bindings/generators/mojom_js_generator.py
diff --git a/mojo/public/tools/bindings/generators/mojom_js_generator.py b/mojo/public/tools/bindings/generators/mojom_js_generator.py
index 5b83974d97943ec15a117e877cd978bef32a1c73..c5f71f60784b667181db170eabcd0bd460dd5272 100644
--- a/mojo/public/tools/bindings/generators/mojom_js_generator.py
+++ b/mojo/public/tools/bindings/generators/mojom_js_generator.py
@@ -138,6 +138,28 @@ def JavaScriptEncodeSnippet(kind):
     return JavaScriptEncodeSnippet(mojom.INT32)
 
 
+def JavaScriptFieldOffset(packed_field):
+  return "offset + codec.kStructHeaderSize + %s" % packed_field.offset
+
+def JavaScriptArrayElementCodecType(elementKind):
+  if elementKind == mojom.BOOL:
+    return "codec.PackedBool"
+  if isinstance(elementKind, mojom.Array) and elementKind.kind == mojom.BOOL:
+    return "new codec.ArrayOf(codec.PackedBool)"
+  return CodecType(elementKind)
+
+def JavaScriptValidateArrayParams(pf):
+  elementKind = pf.field.kind.kind
+  elementSize = pack.PackedField.GetSizeForKind(elementKind)
+  elementCount = generator.ExpectedArraySize(pf.field.kind)
+  elementType = JavaScriptArrayElementCodecType(elementKind)
+  return "%s, %s, %s, %s" % \
+    (JavaScriptFieldOffset(pf), elementSize, elementCount, elementType)
+
+def JavaScriptValidateStructParams(pf):
+  return "%s, %s" % (JavaScriptFieldOffset(pf), pf.field.kind.name)
+
+
 def TranslateConstants(token):
   if isinstance(token, (mojom.EnumValue, mojom.NamedValue)):
     # Both variable and enum constants are constructed like:
@@ -164,6 +186,25 @@ def JavascriptType(kind):
   return kind.name
 
 
+def HasCallbacks(interface):
+  for method in interface.methods:
+    if method.response_parameters != None:
+      return True
+  return False
+
+def IsArrayPointerField(field):
+  return mojom.IsAnyArrayKind(field.kind)
+
+def IsStringPointerField(field):
+  return mojom.IsStringKind(field.kind)
+
+def IsStructPointerField(field):
+  return mojom.IsStructKind(field.kind)
+
+def IsHandleField(field):
+  return mojom.IsAnyHandleKind(field.kind)
+
+
 class Generator(generator.Generator):
 
   js_filters = {
@@ -172,8 +213,16 @@ class Generator(generator.Generator):
     "decode_snippet": JavaScriptDecodeSnippet,
     "encode_snippet": JavaScriptEncodeSnippet,
     "expression_to_text": ExpressionToText,
+    "field_offset": JavaScriptFieldOffset,
+    "has_callbacks": HasCallbacks,
+    "is_array_pointer_field": IsArrayPointerField,
+    "is_struct_pointer_field": IsStructPointerField,
+    "is_string_pointer_field": IsStringPointerField,
+    "is_handle_field": IsHandleField,
     "js_type": JavascriptType,
     "stylize_method": generator.StudlyCapsToCamel,
+    "validate_array_params": JavaScriptValidateArrayParams,
+    "validate_struct_params": JavaScriptValidateStructParams,
   }
 
   @UseJinja("js_templates/module.js.tmpl", filters=js_filters)