uv: improvements to process.binding('uv')

* ensure that UV_... props are constants
* improve error message ... the error message when passing
  in `err >= 0` to `util._errnoException()` was less than
   useful.
* refine uses of process.binding('uv')

PR-URL: https://github.com/nodejs/node/pull/14933
Reviewed-By: Anna Henningsen <anna@addaleax.net>
Reviewed-By: Refael Ackermann <refack@gmail.com>
Reviewed-By: Colin Ihrig <cjihrig@gmail.com>

1 files changed, 3 insertions, 6 deletions

diff --git a/src/uv.cc b/src/uv.cc
index 3e345374a2..260aae92a7 100644
--- a/src/uv.cc
+++ b/src/uv.cc
@@ -29,7 +29,6 @@ namespace {
 
 using v8::Context;
 using v8::FunctionCallbackInfo;
-using v8::Integer;
 using v8::Local;
 using v8::Object;
 using v8::Value;
@@ -38,8 +37,7 @@ using v8::Value;
 void ErrName(const FunctionCallbackInfo<Value>& args) {
   Environment* env = Environment::GetCurrent(args);
   int err = args[0]->Int32Value();
-  if (err >= 0)
-    return env->ThrowError("err >= 0");
+  CHECK_LT(err, 0);
   const char* name = uv_err_name(err);
   args.GetReturnValue().Set(OneByteString(env->isolate(), name));
 }
@@ -51,9 +49,8 @@ void InitializeUV(Local<Object> target,
   Environment* env = Environment::GetCurrent(context);
   target->Set(FIXED_ONE_BYTE_STRING(env->isolate(), "errname"),
               env->NewFunctionTemplate(ErrName)->GetFunction());
-#define V(name, _)                                                            \
-  target->Set(FIXED_ONE_BYTE_STRING(env->isolate(), "UV_" # name),            \
-              Integer::New(env->isolate(), UV_ ## name));
+
+#define V(name, _) NODE_DEFINE_CONSTANT(target, UV_##name);
   UV_ERRNO_MAP(V)
 #undef V
 }