Adding upstream version 115.8.0esr.upstream/115.8.0esr

Signed-off-by: Daniel Baumann <daniel.baumann@progress-linux.org>

12 files changed, 914 insertions, 0 deletions

diff --git a/ipc/testshell/PTestShell.ipdl b/ipc/testshell/PTestShell.ipdl
new file mode 100644
index 0000000000..f952f59584
--- /dev/null
+++ b/ipc/testshell/PTestShell.ipdl
@@ -0,0 +1,28 @@
+/* -*- Mode: C++; c-basic-offset: 2; indent-tabs-mode: nil; tab-width: 8 -*- */
+/* This Source Code Form is subject to the terms of the Mozilla Public
+ * License, v. 2.0. If a copy of the MPL was not distributed with this
+ * file, You can obtain one at http://mozilla.org/MPL/2.0/. */
+
+include protocol PContent;
+include protocol PTestShellCommand;
+
+namespace mozilla {
+namespace ipc {
+
+[ManualDealloc]
+async protocol PTestShell
+{
+  manager PContent;
+
+  manages PTestShellCommand;
+
+child:
+  async __delete__();
+
+  async ExecuteCommand(nsString aCommand);
+
+  async PTestShellCommand(nsString aCommand);
+};
+
+} // namespace ipc
+} // namespace mozilla
diff --git a/ipc/testshell/PTestShellCommand.ipdl b/ipc/testshell/PTestShellCommand.ipdl
new file mode 100644
index 0000000000..a99c22630d
--- /dev/null
+++ b/ipc/testshell/PTestShellCommand.ipdl
@@ -0,0 +1,23 @@
+/* -*- Mode: C++; c-basic-offset: 2; indent-tabs-mode: nil; tab-width: 8 -*- */
+/* This Source Code Form is subject to the terms of the Mozilla Public
+ * License, v. 2.0. If a copy of the MPL was not distributed with this
+ * file, You can obtain one at http://mozilla.org/MPL/2.0/. */
+
+include protocol PTestShell;
+
+include "mozilla/ipc/TestShellParent.h";
+
+namespace mozilla {
+namespace ipc {
+
+[ManualDealloc, ChildImpl=virtual, ParentImpl="TestShellCommandParent"]
+protocol PTestShellCommand
+{
+  manager PTestShell;
+
+parent:
+  async __delete__(nsString aResponse);
+};
+
+} // namespace ipc
+} // namespace mozilla
diff --git a/ipc/testshell/TestShellChild.cpp b/ipc/testshell/TestShellChild.cpp
new file mode 100644
index 0000000000..6af5630d2d
--- /dev/null
+++ b/ipc/testshell/TestShellChild.cpp
@@ -0,0 +1,54 @@
+/* This Source Code Form is subject to the terms of the Mozilla Public
+ * License, v. 2.0. If a copy of the MPL was not distributed with this
+ * file, You can obtain one at http://mozilla.org/MPL/2.0/. */
+
+#include "TestShellChild.h"
+
+using mozilla::ipc::PTestShellCommandChild;
+using mozilla::ipc::TestShellChild;
+using mozilla::ipc::XPCShellEnvironment;
+
+TestShellChild::TestShellChild()
+    : mXPCShell(XPCShellEnvironment::CreateEnvironment()) {}
+
+mozilla::ipc::IPCResult TestShellChild::RecvExecuteCommand(
+    const nsAString& aCommand) {
+  if (mXPCShell->IsQuitting()) {
+    NS_WARNING("Commands sent after quit command issued!");
+    return IPC_FAIL_NO_REASON(this);
+  }
+
+  if (!mXPCShell->EvaluateString(aCommand)) {
+    return IPC_FAIL_NO_REASON(this);
+  }
+  return IPC_OK();
+}
+
+PTestShellCommandChild* TestShellChild::AllocPTestShellCommandChild(
+    const nsAString& aCommand) {
+  return new PTestShellCommandChild();
+}
+
+bool TestShellChild::DeallocPTestShellCommandChild(
+    PTestShellCommandChild* aCommand) {
+  delete aCommand;
+  return true;
+}
+
+mozilla::ipc::IPCResult TestShellChild::RecvPTestShellCommandConstructor(
+    PTestShellCommandChild* aActor, const nsAString& aCommand) {
+  if (mXPCShell->IsQuitting()) {
+    NS_WARNING("Commands sent after quit command issued!");
+    return IPC_FAIL_NO_REASON(this);
+  }
+
+  nsString response;
+  if (!mXPCShell->EvaluateString(aCommand, &response)) {
+    return IPC_FAIL_NO_REASON(this);
+  }
+
+  if (!PTestShellCommandChild::Send__delete__(aActor, response)) {
+    return IPC_FAIL_NO_REASON(this);
+  }
+  return IPC_OK();
+}
diff --git a/ipc/testshell/TestShellChild.h b/ipc/testshell/TestShellChild.h
new file mode 100644
index 0000000000..12f54549d6
--- /dev/null
+++ b/ipc/testshell/TestShellChild.h
@@ -0,0 +1,40 @@
+/* This Source Code Form is subject to the terms of the Mozilla Public
+ * License, v. 2.0. If a copy of the MPL was not distributed with this
+ * file, You can obtain one at http://mozilla.org/MPL/2.0/. */
+
+#ifndef ipc_testshell_TestShellChild_h
+#define ipc_testshell_TestShellChild_h 1
+
+#include "mozilla/ipc/ProtocolUtils.h"
+#include "mozilla/ipc/PTestShellChild.h"
+#include "mozilla/ipc/PTestShellCommandChild.h"
+#include "mozilla/ipc/XPCShellEnvironment.h"
+
+namespace mozilla {
+
+namespace ipc {
+
+class XPCShellEnvironment;
+
+class TestShellChild : public PTestShellChild {
+ public:
+  TestShellChild();
+
+  mozilla::ipc::IPCResult RecvExecuteCommand(const nsAString& aCommand);
+
+  PTestShellCommandChild* AllocPTestShellCommandChild(
+      const nsAString& aCommand);
+
+  mozilla::ipc::IPCResult RecvPTestShellCommandConstructor(
+      PTestShellCommandChild* aActor, const nsAString& aCommand) override;
+
+  bool DeallocPTestShellCommandChild(PTestShellCommandChild* aCommand);
+
+ private:
+  UniquePtr<XPCShellEnvironment> mXPCShell;
+};
+
+} /* namespace ipc */
+} /* namespace mozilla */
+
+#endif /* ipc_testshell_TestShellChild_h */
diff --git a/ipc/testshell/TestShellParent.cpp b/ipc/testshell/TestShellParent.cpp
new file mode 100644
index 0000000000..8cd8dad08e
--- /dev/null
+++ b/ipc/testshell/TestShellParent.cpp
@@ -0,0 +1,90 @@
+/* This Source Code Form is subject to the terms of the Mozilla Public
+ * License, v. 2.0. If a copy of the MPL was not distributed with this
+ * file, You can obtain one at http://mozilla.org/MPL/2.0/. */
+
+#include "TestShellParent.h"
+
+/* This must occur *after* TestShellParent.h to avoid typedefs conflicts. */
+#include "jsfriendapi.h"
+#include "js/CallAndConstruct.h"  // JS_CallFunctionValue
+
+#include "mozilla/dom/AutoEntryScript.h"
+
+using namespace mozilla;
+using mozilla::ipc::PTestShellCommandParent;
+using mozilla::ipc::TestShellCommandParent;
+using mozilla::ipc::TestShellParent;
+
+void TestShellParent::ActorDestroy(ActorDestroyReason aWhy) {
+  // Implement me! Bug 1005177
+}
+
+PTestShellCommandParent* TestShellParent::AllocPTestShellCommandParent(
+    const nsAString& aCommand) {
+  return new TestShellCommandParent();
+}
+
+bool TestShellParent::DeallocPTestShellCommandParent(
+    PTestShellCommandParent* aActor) {
+  delete aActor;
+  return true;
+}
+
+bool TestShellParent::CommandDone(TestShellCommandParent* command,
+                                  const nsAString& aResponse) {
+  // XXX what should happen if the callback fails?
+  /*bool ok = */ command->RunCallback(aResponse);
+  command->ReleaseCallback();
+
+  return true;
+}
+
+bool TestShellCommandParent::SetCallback(JSContext* aCx,
+                                         const JS::Value& aCallback) {
+  if (!mCallback.initialized()) {
+    mCallback.init(aCx, aCallback);
+    return true;
+  }
+
+  mCallback = aCallback;
+
+  return true;
+}
+
+bool TestShellCommandParent::RunCallback(const nsAString& aResponse) {
+  NS_ENSURE_TRUE(mCallback.isObject(), false);
+
+  MOZ_RELEASE_ASSERT(js::IsFunctionObject(&mCallback.toObject()));
+
+  // We're about to run script via JS_CallFunctionValue, so we need an
+  // AutoEntryScript. This is just for testing and not in any spec.
+  dom::AutoEntryScript aes(&mCallback.toObject(), "TestShellCommand");
+  JSContext* cx = aes.cx();
+  JS::Rooted<JSObject*> global(cx, JS::CurrentGlobalOrNull(cx));
+
+  JSString* str =
+      JS_NewUCStringCopyN(cx, aResponse.BeginReading(), aResponse.Length());
+  NS_ENSURE_TRUE(str, false);
+
+  JS::Rooted<JS::Value> strVal(cx, JS::StringValue(str));
+
+  JS::Rooted<JS::Value> rval(cx);
+  JS::Rooted<JS::Value> callback(cx, mCallback);
+  bool ok = JS_CallFunctionValue(cx, global, callback,
+                                 JS::HandleValueArray(strVal), &rval);
+  NS_ENSURE_TRUE(ok, false);
+
+  return true;
+}
+
+void TestShellCommandParent::ReleaseCallback() { mCallback.reset(); }
+
+bool TestShellCommandParent::ExecuteCallback(const nsAString& aResponse) {
+  return static_cast<TestShellParent*>(Manager())->CommandDone(this, aResponse);
+}
+
+void TestShellCommandParent::ActorDestroy(ActorDestroyReason why) {
+  if (why == AbnormalShutdown) {
+    ExecuteCallback(u""_ns);
+  }
+}
diff --git a/ipc/testshell/TestShellParent.h b/ipc/testshell/TestShellParent.h
new file mode 100644
index 0000000000..ac704f04b2
--- /dev/null
+++ b/ipc/testshell/TestShellParent.h
@@ -0,0 +1,69 @@
+/* -*- Mode: C++; tab-width: 8; indent-tabs-mode: nil; c-basic-offset: 2 -*-
+ * vim: sw=2 ts=8 et :
+ */
+/* This Source Code Form is subject to the terms of the Mozilla Public
+ * License, v. 2.0. If a copy of the MPL was not distributed with this
+ * file, You can obtain one at http://mozilla.org/MPL/2.0/. */
+
+#ifndef ipc_testshell_TestShellParent_h
+#define ipc_testshell_TestShellParent_h 1
+
+#include "mozilla/ipc/PTestShellParent.h"
+#include "mozilla/ipc/PTestShellCommandParent.h"
+
+#include "js/RootingAPI.h"
+#include "js/Value.h"
+#include "nsString.h"
+
+namespace mozilla {
+
+namespace ipc {
+
+class TestShellCommandParent;
+
+class TestShellParent : public PTestShellParent {
+  friend class PTestShellParent;
+
+ public:
+  virtual void ActorDestroy(ActorDestroyReason aWhy) override;
+
+  PTestShellCommandParent* AllocPTestShellCommandParent(
+      const nsAString& aCommand);
+
+  bool DeallocPTestShellCommandParent(PTestShellCommandParent* aActor);
+
+  bool CommandDone(TestShellCommandParent* aActor, const nsAString& aResponse);
+};
+
+class TestShellCommandParent : public PTestShellCommandParent {
+  friend class PTestShellCommandParent;
+
+ public:
+  TestShellCommandParent() = default;
+
+  bool SetCallback(JSContext* aCx, const JS::Value& aCallback);
+
+  bool RunCallback(const nsAString& aResponse);
+
+  void ReleaseCallback();
+
+ protected:
+  bool ExecuteCallback(const nsAString& aResponse);
+
+  void ActorDestroy(ActorDestroyReason why) override;
+
+  mozilla::ipc::IPCResult Recv__delete__(const nsAString& aResponse) {
+    if (!ExecuteCallback(aResponse)) {
+      return IPC_FAIL_NO_REASON(this);
+    }
+    return IPC_OK();
+  }
+
+ private:
+  JS::PersistentRooted<JS::Value> mCallback;
+};
+
+} /* namespace ipc */
+} /* namespace mozilla */
+
+#endif /* ipc_testshell_TestShellParent_h */
diff --git a/ipc/testshell/XPCShellEnvironment.cpp b/ipc/testshell/XPCShellEnvironment.cpp
new file mode 100644
index 0000000000..3d83b36ab4
--- /dev/null
+++ b/ipc/testshell/XPCShellEnvironment.cpp
@@ -0,0 +1,468 @@
+/* -*- Mode: C++; tab-width: 8; indent-tabs-mode: nil; c-basic-offset: 2 -*- */
+/* vim: set ts=8 sts=2 et sw=2 tw=80:
+ * This Source Code Form is subject to the terms of the Mozilla Public
+ * License, v. 2.0. If a copy of the MPL was not distributed with this
+ * file, You can obtain one at http://mozilla.org/MPL/2.0/. */
+
+#ifdef HAVE_IO_H
+#  include <io.h> /* for isatty() */
+#endif
+#ifdef HAVE_UNISTD_H
+#  include <unistd.h> /* for isatty() */
+#endif
+
+#include "jsapi.h"
+#include "js/CharacterEncoding.h"
+#include "js/CompilationAndEvaluation.h"  // JS::Compile{,Utf8File}
+#include "js/PropertyAndElement.h"  // JS_DefineFunctions, JS_DefineProperty, JS_GetProperty
+#include "js/PropertySpec.h"
+#include "js/RealmOptions.h"
+#include "js/SourceText.h"  // JS::Source{Ownership,Text}
+
+#include "xpcpublic.h"
+
+#include "XPCShellEnvironment.h"
+
+#include "mozilla/Utf8.h"  // mozilla::Utf8Unit
+#include "mozilla/dom/AutoEntryScript.h"
+#include "mozilla/dom/ScriptSettings.h"
+
+#include "nsIPrincipal.h"
+#include "nsIScriptSecurityManager.h"
+#include "nsIXPConnect.h"
+#include "nsServiceManagerUtils.h"
+
+#include "nsJSUtils.h"
+
+#include "BackstagePass.h"
+
+#include "TestShellChild.h"
+
+using mozilla::dom::AutoEntryScript;
+using mozilla::dom::AutoJSAPI;
+using mozilla::ipc::XPCShellEnvironment;
+using namespace JS;
+
+namespace {
+
+static const char kDefaultRuntimeScriptFilename[] = "xpcshell.js";
+
+inline XPCShellEnvironment* Environment(JS::Handle<JSObject*> global) {
+  AutoJSAPI jsapi;
+  if (!jsapi.Init(global)) {
+    return nullptr;
+  }
+  JSContext* cx = jsapi.cx();
+  Rooted<Value> v(cx);
+  if (!JS_GetProperty(cx, global, "__XPCShellEnvironment", &v) ||
+      !v.get().isDouble()) {
+    return nullptr;
+  }
+  return static_cast<XPCShellEnvironment*>(v.get().toPrivate());
+}
+
+static bool Print(JSContext* cx, unsigned argc, JS::Value* vp) {
+  JS::CallArgs args = JS::CallArgsFromVp(argc, vp);
+
+  for (unsigned i = 0; i < args.length(); i++) {
+    JS::Rooted<JSString*> str(cx, JS::ToString(cx, args[i]));
+    if (!str) return false;
+    JS::UniqueChars bytes = JS_EncodeStringToUTF8(cx, str);
+    if (!bytes) return false;
+    fprintf(stdout, "%s%s", i ? " " : "", bytes.get());
+    fflush(stdout);
+  }
+  fputc('\n', stdout);
+  args.rval().setUndefined();
+  return true;
+}
+
+static bool GetLine(char* bufp, FILE* file, const char* prompt) {
+  char line[256];
+  fputs(prompt, stdout);
+  fflush(stdout);
+  if (!fgets(line, sizeof line, file)) return false;
+  strcpy(bufp, line);
+  return true;
+}
+
+static bool Dump(JSContext* cx, unsigned argc, JS::Value* vp) {
+  JS::CallArgs args = JS::CallArgsFromVp(argc, vp);
+
+  if (!args.length()) return true;
+
+  JS::Rooted<JSString*> str(cx, JS::ToString(cx, args[0]));
+  if (!str) return false;
+  JS::UniqueChars bytes = JS_EncodeStringToUTF8(cx, str);
+  if (!bytes) return false;
+
+  fputs(bytes.get(), stdout);
+  fflush(stdout);
+  return true;
+}
+
+static bool Load(JSContext* cx, unsigned argc, JS::Value* vp) {
+  JS::CallArgs args = JS::CallArgsFromVp(argc, vp);
+
+  JS::RootedObject thisObject(cx);
+  if (!args.computeThis(cx, &thisObject)) return false;
+  if (!JS_IsGlobalObject(thisObject)) {
+    JS_ReportErrorASCII(cx, "Trying to load() into a non-global object");
+    return false;
+  }
+
+  for (unsigned i = 0; i < args.length(); i++) {
+    JS::Rooted<JSString*> str(cx, JS::ToString(cx, args[i]));
+    if (!str) {
+      return false;
+    }
+    JS::UniqueChars filename = JS_EncodeStringToUTF8(cx, str);
+    if (!filename) {
+      return false;
+    }
+
+    JS::CompileOptions options(cx);
+    JS::Rooted<JSScript*> script(
+        cx, JS::CompileUtf8Path(cx, options, filename.get()));
+    if (!script) {
+      return false;
+    }
+
+    if (!JS_ExecuteScript(cx, script)) {
+      return false;
+    }
+  }
+  args.rval().setUndefined();
+  return true;
+}
+
+static bool Quit(JSContext* cx, unsigned argc, JS::Value* vp) {
+  Rooted<JSObject*> global(cx, JS::CurrentGlobalOrNull(cx));
+  XPCShellEnvironment* env = Environment(global);
+  env->SetIsQuitting();
+
+  return false;
+}
+
+static bool DumpXPC(JSContext* cx, unsigned argc, JS::Value* vp) {
+  JS::CallArgs args = CallArgsFromVp(argc, vp);
+
+  uint16_t depth = 2;
+  if (args.length() > 0) {
+    if (!JS::ToUint16(cx, args[0], &depth)) return false;
+  }
+
+  nsCOMPtr<nsIXPConnect> xpc = nsIXPConnect::XPConnect();
+  if (xpc) xpc->DebugDump(int16_t(depth));
+  args.rval().setUndefined();
+  return true;
+}
+
+static bool GC(JSContext* cx, unsigned argc, JS::Value* vp) {
+  JS::CallArgs args = JS::CallArgsFromVp(argc, vp);
+
+  JS_GC(cx);
+
+  args.rval().setUndefined();
+  return true;
+}
+
+#ifdef JS_GC_ZEAL
+static bool GCZeal(JSContext* cx, unsigned argc, JS::Value* vp) {
+  CallArgs args = CallArgsFromVp(argc, vp);
+
+  uint32_t zeal;
+  if (!ToUint32(cx, args.get(0), &zeal)) return false;
+
+  JS_SetGCZeal(cx, uint8_t(zeal), JS_DEFAULT_ZEAL_FREQ);
+  return true;
+}
+#endif
+
+#ifdef ANDROID
+static bool ChangeTestShellDir(JSContext* cx, unsigned argc, Value* vp) {
+  // This method should only be used by testing/xpcshell/head.js to change to
+  // the correct directory on Android Remote XPCShell tests.
+  //
+  // TODO: Bug 1801725 - Find a more ergonomic way to do this than exposing
+  // identical methods in XPCShellEnvironment and XPCShellImpl to chdir on
+  // android for Remote XPCShell tests on Android.
+  CallArgs args = CallArgsFromVp(argc, vp);
+
+  if (args.length() != 1) {
+    JS_ReportErrorASCII(cx, "changeTestShellDir() takes one argument");
+    return false;
+  }
+
+  nsAutoJSCString path;
+  if (!path.init(cx, args[0])) {
+    JS_ReportErrorASCII(
+        cx, "changeTestShellDir(): could not convert argument 1 to string");
+    return false;
+  }
+
+  if (chdir(path.get())) {
+    JS_ReportErrorASCII(cx, "changeTestShellDir(): could not change directory");
+    return false;
+  }
+
+  return true;
+}
+#endif
+
+const JSFunctionSpec gGlobalFunctions[] = {
+    JS_FN("print", Print, 0, 0),
+    JS_FN("load", Load, 1, 0),
+    JS_FN("quit", Quit, 0, 0),
+    JS_FN("dumpXPC", DumpXPC, 1, 0),
+    JS_FN("dump", Dump, 1, 0),
+    JS_FN("gc", GC, 0, 0),
+#ifdef JS_GC_ZEAL
+    JS_FN("gczeal", GCZeal, 1, 0),
+#endif
+#ifdef ANDROID
+    JS_FN("changeTestShellDir", ChangeTestShellDir, 1, 0),
+#endif
+    JS_FS_END};
+
+typedef enum JSShellErrNum {
+#define MSG_DEF(name, number, count, exception, format) name = number,
+#include "jsshell.msg"
+#undef MSG_DEF
+  JSShellErr_Limit
+#undef MSGDEF
+} JSShellErrNum;
+
+} /* anonymous namespace */
+
+void XPCShellEnvironment::ProcessFile(JSContext* cx, const char* filename,
+                                      FILE* file, bool forceTTY) {
+  XPCShellEnvironment* env = this;
+
+  JS::Rooted<JS::Value> result(cx);
+  int lineno, startline;
+  bool ok, hitEOF;
+  char *bufp, buffer[4096];
+  JSString* str;
+
+  JS::Rooted<JSObject*> global(cx, JS::CurrentGlobalOrNull(cx));
+  MOZ_ASSERT(global);
+
+  if (forceTTY) {
+    file = stdin;
+  } else if (!isatty(fileno(file))) {
+    /*
+     * It's not interactive - just execute it.
+     *
+     * Support the UNIX #! shell hack; gobble the first line if it starts
+     * with '#'.
+     */
+    int ch = fgetc(file);
+    if (ch == '#') {
+      while ((ch = fgetc(file)) != EOF) {
+        if (ch == '\n' || ch == '\r') break;
+      }
+    }
+    ungetc(ch, file);
+
+    JS::CompileOptions options(cx);
+    options.setFileAndLine(filename, 1);
+
+    JS::Rooted<JSScript*> script(cx, JS::CompileUtf8File(cx, options, file));
+    if (script) {
+      (void)JS_ExecuteScript(cx, script, &result);
+    }
+
+    return;
+  }
+
+  /* It's an interactive filehandle; drop into read-eval-print loop. */
+  lineno = 1;
+  hitEOF = false;
+  do {
+    bufp = buffer;
+    *bufp = '\0';
+
+    /*
+     * Accumulate lines until we get a 'compilable unit' - one that either
+     * generates an error (before running out of source) or that compiles
+     * cleanly.  This should be whenever we get a complete statement that
+     * coincides with the end of a line.
+     */
+    startline = lineno;
+    do {
+      if (!GetLine(bufp, file, startline == lineno ? "js> " : "")) {
+        hitEOF = true;
+        break;
+      }
+      bufp += strlen(bufp);
+      lineno++;
+    } while (
+        !JS_Utf8BufferIsCompilableUnit(cx, global, buffer, strlen(buffer)));
+
+    /* Clear any pending exception from previous failed compiles.  */
+    JS_ClearPendingException(cx);
+
+    JS::CompileOptions options(cx);
+    options.setFileAndLine("typein", startline);
+
+    JS::SourceText<mozilla::Utf8Unit> srcBuf;
+    JS::Rooted<JSScript*> script(cx);
+
+    if (srcBuf.init(cx, buffer, strlen(buffer),
+                    JS::SourceOwnership::Borrowed) &&
+        (script = JS::Compile(cx, options, srcBuf))) {
+      ok = JS_ExecuteScript(cx, script, &result);
+      if (ok && !result.isUndefined()) {
+        /* Suppress warnings from JS::ToString(). */
+        JS::AutoSuppressWarningReporter suppressWarnings(cx);
+        str = JS::ToString(cx, result);
+        JS::UniqueChars bytes;
+        if (str) bytes = JS_EncodeStringToLatin1(cx, str);
+
+        if (!!bytes)
+          fprintf(stdout, "%s\n", bytes.get());
+        else
+          ok = false;
+      }
+    }
+  } while (!hitEOF && !env->IsQuitting());
+
+  fprintf(stdout, "\n");
+}
+
+// static
+XPCShellEnvironment* XPCShellEnvironment::CreateEnvironment() {
+  auto* env = new XPCShellEnvironment();
+  if (env && !env->Init()) {
+    delete env;
+    env = nullptr;
+  }
+  return env;
+}
+
+XPCShellEnvironment::XPCShellEnvironment() : mQuitting(false) {}
+
+XPCShellEnvironment::~XPCShellEnvironment() {
+  if (GetGlobalObject()) {
+    AutoJSAPI jsapi;
+    if (!jsapi.Init(GetGlobalObject())) {
+      return;
+    }
+    JS_SetAllNonReservedSlotsToUndefined(mGlobalHolder);
+    mGlobalHolder.reset();
+
+    JS_GC(jsapi.cx());
+  }
+}
+
+bool XPCShellEnvironment::Init() {
+  nsresult rv;
+
+  // unbuffer stdout so that output is in the correct order; note that stderr
+  // is unbuffered by default
+  setbuf(stdout, 0);
+
+  AutoSafeJSContext cx;
+
+  mGlobalHolder.init(cx);
+
+  nsCOMPtr<nsIPrincipal> principal;
+  nsCOMPtr<nsIScriptSecurityManager> securityManager =
+      do_GetService(NS_SCRIPTSECURITYMANAGER_CONTRACTID, &rv);
+  if (NS_SUCCEEDED(rv) && securityManager) {
+    rv = securityManager->GetSystemPrincipal(getter_AddRefs(principal));
+    if (NS_FAILED(rv)) {
+      fprintf(stderr,
+              "+++ Failed to obtain SystemPrincipal from ScriptSecurityManager "
+              "service.\n");
+    }
+  } else {
+    fprintf(stderr,
+            "+++ Failed to get ScriptSecurityManager service, running without "
+            "principals");
+  }
+
+  auto backstagePass = MakeRefPtr<BackstagePass>();
+
+  JS::RealmOptions options;
+  options.creationOptions().setNewCompartmentInSystemZone();
+  xpc::SetPrefableRealmOptions(options);
+
+  JS::Rooted<JSObject*> globalObj(cx);
+  rv = xpc::InitClassesWithNewWrappedGlobal(
+      cx, static_cast<nsIGlobalObject*>(backstagePass), principal, 0, options,
+      &globalObj);
+  if (NS_FAILED(rv)) {
+    NS_ERROR("InitClassesWithNewWrappedGlobal failed!");
+    return false;
+  }
+
+  if (!globalObj) {
+    NS_ERROR("Failed to get global JSObject!");
+    return false;
+  }
+  JSAutoRealm ar(cx, globalObj);
+
+  backstagePass->SetGlobalObject(globalObj);
+
+  JS::Rooted<Value> privateVal(cx, PrivateValue(this));
+  if (!JS_DefineProperty(cx, globalObj, "__XPCShellEnvironment", privateVal,
+                         JSPROP_READONLY | JSPROP_PERMANENT) ||
+      !JS_DefineFunctions(cx, globalObj, gGlobalFunctions)) {
+    NS_ERROR("JS_DefineFunctions failed!");
+    return false;
+  }
+
+  mGlobalHolder = globalObj;
+
+  FILE* runtimeScriptFile = fopen(kDefaultRuntimeScriptFilename, "r");
+  if (runtimeScriptFile) {
+    fprintf(stdout, "[loading '%s'...]\n", kDefaultRuntimeScriptFilename);
+    ProcessFile(cx, kDefaultRuntimeScriptFilename, runtimeScriptFile, false);
+    fclose(runtimeScriptFile);
+  }
+
+  return true;
+}
+
+bool XPCShellEnvironment::EvaluateString(const nsAString& aString,
+                                         nsString* aResult) {
+  AutoEntryScript aes(GetGlobalObject(),
+                      "ipc XPCShellEnvironment::EvaluateString");
+  JSContext* cx = aes.cx();
+
+  JS::CompileOptions options(cx);
+  options.setFileAndLine("typein", 0);
+
+  JS::SourceText<char16_t> srcBuf;
+  if (!srcBuf.init(cx, aString.BeginReading(), aString.Length(),
+                   JS::SourceOwnership::Borrowed)) {
+    return false;
+  }
+
+  JS::Rooted<JSScript*> script(cx, JS::Compile(cx, options, srcBuf));
+  if (!script) {
+    return false;
+  }
+
+  if (aResult) {
+    aResult->Truncate();
+  }
+
+  JS::Rooted<JS::Value> result(cx);
+  bool ok = JS_ExecuteScript(cx, script, &result);
+  if (ok && !result.isUndefined()) {
+    /* Suppress warnings from JS::ToString(). */
+    JS::AutoSuppressWarningReporter suppressWarnings(cx);
+    JSString* str = JS::ToString(cx, result);
+    nsAutoJSString autoStr;
+    if (str) autoStr.init(cx, str);
+
+    if (!autoStr.IsEmpty() && aResult) {
+      aResult->Assign(autoStr);
+    }
+  }
+
+  return true;
+}
diff --git a/ipc/testshell/XPCShellEnvironment.h b/ipc/testshell/XPCShellEnvironment.h
new file mode 100644
index 0000000000..b479ec85b6
--- /dev/null
+++ b/ipc/testshell/XPCShellEnvironment.h
@@ -0,0 +1,57 @@
+/* This Source Code Form is subject to the terms of the Mozilla Public
+ * License, v. 2.0. If a copy of the MPL was not distributed with this
+ * file, You can obtain one at http://mozilla.org/MPL/2.0/. */
+
+#ifndef _IPC_TESTSHELL_XPCSHELLENVIRONMENT_H_
+#define _IPC_TESTSHELL_XPCSHELLENVIRONMENT_H_
+
+#include "base/basictypes.h"
+
+#include <string>
+#include <stdio.h>
+
+#include "nsCOMPtr.h"
+#include "nsDebug.h"
+#include "nsString.h"
+#include "nsJSPrincipals.h"
+#include "nsContentUtils.h"
+#include "js/RootingAPI.h"
+#include "js/TypeDecls.h"
+
+struct JSPrincipals;
+
+namespace mozilla {
+namespace ipc {
+
+class XPCShellEnvironment {
+ public:
+  static XPCShellEnvironment* CreateEnvironment();
+  ~XPCShellEnvironment();
+
+  void ProcessFile(JSContext* cx, const char* filename, FILE* file,
+                   bool forceTTY);
+  bool EvaluateString(const nsAString& aString, nsString* aResult = nullptr);
+
+  JSPrincipals* GetPrincipal() {
+    return nsJSPrincipals::get(nsContentUtils::GetSystemPrincipal());
+  }
+
+  JSObject* GetGlobalObject() { return mGlobalHolder; }
+
+  void SetIsQuitting() { mQuitting = true; }
+  bool IsQuitting() { return mQuitting; }
+
+ protected:
+  XPCShellEnvironment();
+  bool Init();
+
+ private:
+  JS::PersistentRooted<JSObject*> mGlobalHolder;
+
+  bool mQuitting;
+};
+
+} /* namespace ipc */
+} /* namespace mozilla */
+
+#endif /* _IPC_TESTSHELL_XPCSHELLENVIRONMENT_H_ */
diff --git a/ipc/testshell/moz.build b/ipc/testshell/moz.build
new file mode 100644
index 0000000000..56447a7165
--- /dev/null
+++ b/ipc/testshell/moz.build
@@ -0,0 +1,37 @@
+# -*- Mode: python; indent-tabs-mode: nil; tab-width: 40 -*-
+# vim: set filetype=python:
+# This Source Code Form is subject to the terms of the Mozilla Public
+# License, v. 2.0. If a copy of the MPL was not distributed with this
+# file, You can obtain one at http://mozilla.org/MPL/2.0/.
+
+EXPORTS.mozilla.ipc += [
+    "TestShellChild.h",
+    "TestShellParent.h",
+    "XPCShellEnvironment.h",
+]
+
+XPCSHELL_TESTS_MANIFESTS += ["tests/xpcshell.ini"]
+
+SOURCES += [
+    "TestShellChild.cpp",
+    "TestShellParent.cpp",
+    "XPCShellEnvironment.cpp",
+]
+
+IPDL_SOURCES = [
+    "PTestShell.ipdl",
+    "PTestShellCommand.ipdl",
+]
+
+include("/ipc/chromium/chromium-config.mozbuild")
+
+FINAL_LIBRARY = "xul"
+
+# For xpcshell error messages and nsAutoJSString
+LOCAL_INCLUDES += [
+    "/dom/base",
+    "/js/xpconnect/src",
+]
+
+with Files("**"):
+    BUG_COMPONENT = ("Core", "XPConnect")
diff --git a/ipc/testshell/tests/test_ipcshell.js b/ipc/testshell/tests/test_ipcshell.js
new file mode 100644
index 0000000000..3e2e54e670
--- /dev/null
+++ b/ipc/testshell/tests/test_ipcshell.js
@@ -0,0 +1,34 @@
+// eslint-disable-next-line mozilla/use-services
+const runtime = Cc["@mozilla.org/xre/app-info;1"].getService(Ci.nsIXULRuntime);
+
+function callback(result) {
+  Assert.equal(result, Ci.nsIXULRuntime.PROCESS_TYPE_CONTENT);
+  do_test_finished();
+}
+
+function run_test() {
+  do_test_pending();
+
+  Assert.equal(runtime.processType, Ci.nsIXULRuntime.PROCESS_TYPE_DEFAULT);
+
+  sendCommand("load('test_ipcshell_child.js');");
+
+  sendCommand("runtime.processType;", callback);
+
+  [
+    ["C", "D"],
+    ["D", "C"],
+    ["\u010C", "D"],
+    ["D", "\u010C"],
+  ].forEach(function (pair) {
+    do_test_pending();
+    var cmp = pair[0].localeCompare(pair[1]);
+    sendCommand(
+      "'" + pair[0] + "'.localeCompare('" + pair[1] + "');",
+      function (result) {
+        Assert.equal(cmp, result);
+        do_test_finished();
+      }
+    );
+  });
+}
diff --git a/ipc/testshell/tests/test_ipcshell_child.js b/ipc/testshell/tests/test_ipcshell_child.js
new file mode 100644
index 0000000000..f2a0e1e245
--- /dev/null
+++ b/ipc/testshell/tests/test_ipcshell_child.js
@@ -0,0 +1,6 @@
+// eslint-disable-next-line mozilla/use-services
+const runtime = Cc["@mozilla.org/xre/app-info;1"].getService(Ci.nsIXULRuntime);
+
+function run_test() {
+  Assert.equal(runtime.processType, Ci.nsIXULRuntime.PROCESS_TYPE_DEFAULT);
+}
diff --git a/ipc/testshell/tests/xpcshell.ini b/ipc/testshell/tests/xpcshell.ini
new file mode 100644
index 0000000000..3dfd85b2ea
--- /dev/null
+++ b/ipc/testshell/tests/xpcshell.ini
@@ -0,0 +1,8 @@
+[DEFAULT]
+head = 
+skip-if = toolkit == 'android'
+
+[test_ipcshell.js]
+# Bug 676963: test fails consistently on Android
+fail-if = os == "android"
+[test_ipcshell_child.js]