Issue #618 - Simplify module resolve hook to be a function pointer

This is an ahead-of time port to try and address #1624.
This is based on BZ 1461751 and Jon Coppeard's work in it.

1 files changed, 29 insertions, 4 deletions

diff --git a/js/src/shell/js.cpp b/js/src/shell/js.cpp
index 8cd821b311..bbf35459ff 100644
--- a/js/src/shell/js.cpp
+++ b/js/src/shell/js.cpp
@@ -274,6 +274,7 @@ struct ShellContext
     JS::PersistentRooted<JobQueue> jobQueue;
     ExclusiveData<ShellAsyncTasks> asyncTasks;
     bool drainingJobQueue;
+    JS::PersistentRootedFunction moduleResolveHook;
 
     /*
      * Watchdog thread state.
@@ -439,7 +440,8 @@ ShellContext::ShellContext(JSContext* cx)
     exitCode(0),
     quitting(false),
     readLineBufPos(0),
-    spsProfilingStackSize(0)
+    spsProfilingStackSize(0),
+    moduleResolveHook(cx)
 {}
 
 static ShellContext*
@@ -4030,13 +4032,34 @@ SetModuleResolveHook(JSContext* cx, unsigned argc, Value* vp)
         return false;
     }
 
-    RootedFunction hook(cx, &args[0].toObject().as<JSFunction>());
-    Rooted<GlobalObject*> global(cx, cx->global());
-    global->setModuleResolveHook(hook);
+    ShellContext* sc = GetShellContext(cx);
+    sc->moduleResolveHook = &args[0].toObject().as<JSFunction>();
+
     args.rval().setUndefined();
     return true;
 }
 
+static JSObject*
+CallModuleResolveHook(JSContext* cx, HandleObject module, HandleString specifier)
+{
+    ShellContext* sc = GetShellContext(cx);
+
+    JS::AutoValueArray<2> args(cx);
+    args[0].setObject(*module);
+    args[1].setString(specifier);
+
+    RootedValue result(cx);
+    if (!JS_CallFunction(cx, nullptr, sc->moduleResolveHook, args, &result))
+        return nullptr;
+
+    if (!result.isObject() || !result.toObject().is<ModuleObject>()) {
+         JS_ReportErrorASCII(cx, "Module resolve hook did not return Module object");
+         return nullptr;
+    }
+
+    return &result.toObject();
+}
+
 static bool
 GetModuleLoadPath(JSContext* cx, unsigned argc, Value* vp)
 {
@@ -7962,6 +7985,8 @@ main(int argc, char** argv, char** envp)
 
     js::SetPreserveWrapperCallback(cx, DummyPreserveWrapperCallback);
 
+    JS::SetModuleResolveHook(cx->runtime(), CallModuleResolveHook);
+
     result = Shell(cx, &op, envp);
 
 #ifdef DEBUG