# HG changeset patch
# User Tooru Fujisawa <arai_a@mac.com>
# Date 1451931683 -32400
#      Tue Jan 05 03:21:23 2016 +0900
# Node ID c57006f58b390d1d4020e4262cb3aedfc2734b55
# Parent  0771c5eab32f0cee4f7d12bc382298a81e0eabb2
Bug 1180290 - Part 1: Add prefix parameter to IdToFunctionName.

diff --git a/js/src/jsfun.cpp b/js/src/jsfun.cpp
--- a/js/src/jsfun.cpp
+++ b/js/src/jsfun.cpp
@@ -2253,31 +2253,48 @@ js::CloneFunctionAndScript(JSContext* cx
  * property id.
  *
  * Function names are always strings. If id is the well-known @@iterator
  * symbol, this returns "[Symbol.iterator]".
  *
  * Implements step 4 of SetFunctionName in ES6 draft rev 27 (24 Aug 2014).
  */
 JSAtom*
-js::IdToFunctionName(JSContext* cx, HandleId id)
+js::IdToFunctionName(JSContext* cx, HandleId id, const char* prefix)
 {
-    if (JSID_IS_ATOM(id))
-        return JSID_TO_ATOM(id);
+    if (JSID_IS_ATOM(id)) {
+        if (!prefix)
+            return JSID_TO_ATOM(id);
+
+        StringBuffer sb(cx);
+        if (!sb.append(prefix, strlen(prefix)) || !sb.append(' ') || !sb.append(JSID_TO_ATOM(id)))
+            return nullptr;
+        return sb.finishAtom();
+    }
 
     if (JSID_IS_SYMBOL(id)) {
         RootedAtom desc(cx, JSID_TO_SYMBOL(id)->description());
         StringBuffer sb(cx);
+        if (prefix) {
+            if (!sb.append(prefix, strlen(prefix)) || !sb.append(' '))
+                return nullptr;
+        }
         if (!sb.append('[') || !sb.append(desc) || !sb.append(']'))
             return nullptr;
         return sb.finishAtom();
     }
 
     RootedValue idv(cx, IdToValue(id));
-    return ToAtom<CanGC>(cx, idv);
+    if (!prefix)
+        return ToAtom<CanGC>(cx, idv);
+
+    StringBuffer sb(cx);
+    if (!sb.append(prefix, strlen(prefix)) || !sb.append(' ') || !sb.append(ToAtom<CanGC>(cx, idv)))
+        return nullptr;
+    return sb.finishAtom();
 }
 
 JSFunction*
 js::DefineFunction(JSContext* cx, HandleObject obj, HandleId id, Native native,
                    unsigned nargs, unsigned flags, AllocKind allocKind /* = AllocKind::FUNCTION */)
 {
     GetterOp gop;
     SetterOp sop;
diff --git a/js/src/jsfun.h b/js/src/jsfun.h
--- a/js/src/jsfun.h
+++ b/js/src/jsfun.h
@@ -659,17 +659,17 @@ enum NewFunctionProtoHandling {
 extern JSFunction*
 NewFunctionWithProto(ExclusiveContext* cx, JSNative native, unsigned nargs,
                      JSFunction::Flags flags, HandleObject enclosingDynamicScope, HandleAtom atom,
                      HandleObject proto, gc::AllocKind allocKind = gc::AllocKind::FUNCTION,
                      NewObjectKind newKind = GenericObject,
                      NewFunctionProtoHandling protoHandling = NewFunctionClassProto);
 
 extern JSAtom*
-IdToFunctionName(JSContext* cx, HandleId id);
+IdToFunctionName(JSContext* cx, HandleId id, const char* prefix=nullptr);
 
 extern JSFunction*
 DefineFunction(JSContext* cx, HandleObject obj, HandleId id, JSNative native,
                unsigned nargs, unsigned flags,
                gc::AllocKind allocKind = gc::AllocKind::FUNCTION);
 
 bool
 FunctionHasResolveHook(const JSAtomState& atomState, jsid id);