From a6ffc52beae131aa08c808aed7ae08149d63021e Mon Sep 17 00:00:00 2001
From: Ryan Macnak <rmacnak@google.com>
Date: Thu, 16 Apr 2015 15:49:11 -0700
Subject: [PATCH] Ensure isolates have a root library so createMirrorSystem()
 and spawnUri() are happy.

https://github.com/domokit/mojo/issues/98

R=eseidel@chromium.org

Review URL: https://codereview.chromium.org/1088263004
---
 engine/core/script/dart_controller.cc |  8 ++++++++
 tests/dart/mirror-system-expected.txt |  1 +
 tests/dart/mirror-system.sky          | 14 ++++++++++++++
 3 files changed, 23 insertions(+)
 create mode 100644 tests/dart/mirror-system-expected.txt
 create mode 100644 tests/dart/mirror-system.sky

diff --git a/engine/core/script/dart_controller.cc b/engine/core/script/dart_controller.cc
index 2a05e588552..dc7ce4c78a6 100644
--- a/engine/core/script/dart_controller.cc
+++ b/engine/core/script/dart_controller.cc
@@ -204,6 +204,10 @@ static Dart_Isolate IsolateCreateCallback(const char* script_uri,
     DartApiScope apiScope;
     Builtin::SetNativeResolver(Builtin::kBuiltinLibrary);
     Builtin::SetNativeResolver(Builtin::kMojoInternalLibrary);
+
+    // Ensure the isolate has a root library.
+    Dart_LoadScript(Dart_NewStringFromCString("dart:empty"),
+                    Dart_NewStringFromCString(""), 0, 0);
   }
 
   Dart_ExitIsolate();
@@ -273,6 +277,10 @@ void DartController::CreateIsolateFor(Document* document) {
   {
     DartApiScope apiScope;
 
+    // Ensure the isolate has a root library.
+    Dart_LoadScript(Dart_NewStringFromCString("dart:empty"),
+                    Dart_NewStringFromCString(""), 0, 0);
+
     Builtin::SetNativeResolver(Builtin::kBuiltinLibrary);
     Builtin::SetNativeResolver(Builtin::kMojoInternalLibrary);
     BuiltinNatives::Init();
diff --git a/tests/dart/mirror-system-expected.txt b/tests/dart/mirror-system-expected.txt
new file mode 100644
index 00000000000..7ef22e9a431
--- /dev/null
+++ b/tests/dart/mirror-system-expected.txt
@@ -0,0 +1 @@
+PASS
diff --git a/tests/dart/mirror-system.sky b/tests/dart/mirror-system.sky
new file mode 100644
index 00000000000..7d751e516dc
--- /dev/null
+++ b/tests/dart/mirror-system.sky
@@ -0,0 +1,14 @@
+<script>
+import "dart:mirrors";
+import "dart:sky.internals" as internals;
+
+// Regression test for the embedder not setting up the root library.
+// Used to crash.
+
+void main() {
+  if (currentMirrorSystem().isolate.rootLibrary == null) {
+    throw "Missing root library";
+  }
+  internals.notifyTestComplete("PASS");
+}
+</script>>