Fix __ENV polution

js/bundle.go

@@ -60,6 +60,9 @@ type BundleInstance struct {
 	Runtime *goja.Runtime
 	Context *context.Context
 
+	//TODO: maybe just have a reference to the Bundle? or save and pass rtOpts?
+	env map[string]string
+
 	exports map[string]goja.Callable
 }
 
@@ -235,6 +238,7 @@ func (b *Bundle) Instantiate() (bi *BundleInstance, instErr error) {
 		Runtime: rt,
 		Context: ctxPtr,
 		exports: make(map[string]goja.Callable),
+		env:     b.Env,
 	}
 
 	// Grab any exported functions that could be executed. These were

js/runner.go

@@ -396,13 +396,14 @@ func (u *VU) Activate(params *lib.VUActivationParams) lib.ActiveVU {
 	}
 
 	// Override the preset global env with any custom env vars
-	if len(params.Env) > 0 {
-		env := u.Runtime.Get("__ENV").Export().(map[string]string)
-		for key, value := range params.Env {
-			env[key] = value
-		}
-		u.Runtime.Set("__ENV", env)
+	env := make(map[string]string, len(u.env)+len(params.Env))
+	for key, value := range u.env {
+		env[key] = value
+	}
+	for key, value := range params.Env {
+		env[key] = value
 	}
+	u.Runtime.Set("__ENV", env)
 
 	avu := &ActiveVU{
 		VU:                 u,