From ba055daed8ce18ab0b3d5feddf8d3974652593a3 Mon Sep 17 00:00:00 2001
From: Yoshi Cheng-Hao Huang <allstars.chh@gmail.com>
Date: Mon, 18 Mar 2024 14:04:14 +0000
Subject: [PATCH] Bug 1873610 - Part 1: Add ModuleObject::filename(). r=jonco

Differential Revision: https://phabricator.services.mozilla.com/D204862
---
 js/src/builtin/ModuleObject.cpp | 11 +++++++++++
 js/src/builtin/ModuleObject.h   |  1 +
 2 files changed, 12 insertions(+)

diff --git a/js/src/builtin/ModuleObject.cpp b/js/src/builtin/ModuleObject.cpp
index b9db9bf02d9d..0365f744a629 100644
--- a/js/src/builtin/ModuleObject.cpp
+++ b/js/src/builtin/ModuleObject.cpp
@@ -1109,6 +1109,17 @@ JSScript* ModuleObject::script() const {
   return ptr;
 }
 
+const char* ModuleObject::filename() const {
+  // The ScriptSlot will be cleared once the module is evaluated, so we try to
+  // get the filename from cyclicModuleFields().
+
+  // TODO: Bug 1885483: Provide filename for JSON modules
+  if (!hasCyclicModuleFields()) {
+    return "(JSON module)";
+  }
+  return cyclicModuleFields()->scriptSourceObject->source()->filename();
+}
+
 static inline void AssertValidModuleStatus(ModuleStatus status) {
   MOZ_ASSERT(status >= ModuleStatus::Unlinked &&
              status <= ModuleStatus::Evaluated_Error);
diff --git a/js/src/builtin/ModuleObject.h b/js/src/builtin/ModuleObject.h
index d39d65b18c5c..cb74d67c40f3 100644
--- a/js/src/builtin/ModuleObject.h
+++ b/js/src/builtin/ModuleObject.h
@@ -360,6 +360,7 @@ class ModuleObject : public NativeObject {
 
   JSScript* maybeScript() const;
   JSScript* script() const;
+  const char* filename() const;
   ModuleEnvironmentObject& initialEnvironment() const;
   ModuleEnvironmentObject* environment() const;
   ModuleNamespaceObject* namespace_();