Introduce safer CJS_Return::Success() and Failure().

Avoid the possibility of ever re-introducing the issue noticed
last week.

Remove some redundant JSGetStringFromID() calls.

Change-Id: I56687c2191bd72e378f747083f34080e50cbe490
Reviewed-on: https://pdfium-review.googlesource.com/40490
Reviewed-by: Lei Zhang <thestig@chromium.org>
Commit-Queue: Tom Sepez <tsepez@chromium.org>

1 files changed, 55 insertions, 66 deletions

diff --git a/fxjs/cjs_event.cpp b/fxjs/cjs_event.cpp
index 9594f13477..f00f07c3b9 100644
--- a/fxjs/cjs_event.cpp
+++ b/fxjs/cjs_event.cpp
@@ -55,10 +55,10 @@ CJS_Event::CJS_Event(v8::Local<v8::Object> pObject, CJS_Runtime* pRuntime)
 CJS_Event::~CJS_Event() = default;
 
 CJS_Return CJS_Event::get_change(CJS_Runtime* pRuntime) {
-  ASSERT(pRuntime->GetCurrentEventContext());
   CJS_EventHandler* pEvent =
       pRuntime->GetCurrentEventContext()->GetEventHandler();
-  return CJS_Return(pRuntime->NewString(pEvent->Change().AsStringView()));
+  return CJS_Return::Success(
+      pRuntime->NewString(pEvent->Change().AsStringView()));
 }
 
 CJS_Return CJS_Event::set_change(CJS_Runtime* pRuntime,
@@ -72,123 +72,116 @@ CJS_Return CJS_Event::set_change(CJS_Runtime* pRuntime,
     WideString& wChange = pEvent->Change();
     wChange = pRuntime->ToWideString(vp);
   }
-  return CJS_Return();
+  return CJS_Return::Success();
 }
 
 CJS_Return CJS_Event::get_change_ex(CJS_Runtime* pRuntime) {
-  ASSERT(pRuntime->GetCurrentEventContext());
   CJS_EventHandler* pEvent =
       pRuntime->GetCurrentEventContext()->GetEventHandler();
-
-  return CJS_Return(pRuntime->NewString(pEvent->ChangeEx().AsStringView()));
+  return CJS_Return::Success(
+      pRuntime->NewString(pEvent->ChangeEx().AsStringView()));
 }
 
 CJS_Return CJS_Event::set_change_ex(CJS_Runtime* pRuntime,
                                     v8::Local<v8::Value> vp) {
-  return CJS_Return(JSMessage::kNotSupportedError);
+  return CJS_Return::Failure(JSMessage::kNotSupportedError);
 }
 
 CJS_Return CJS_Event::get_commit_key(CJS_Runtime* pRuntime) {
-  ASSERT(pRuntime->GetCurrentEventContext());
-
   CJS_EventHandler* pEvent =
       pRuntime->GetCurrentEventContext()->GetEventHandler();
-
-  return CJS_Return(pRuntime->NewNumber(pEvent->CommitKey()));
+  return CJS_Return::Success(pRuntime->NewNumber(pEvent->CommitKey()));
 }
 
 CJS_Return CJS_Event::set_commit_key(CJS_Runtime* pRuntime,
                                      v8::Local<v8::Value> vp) {
-  return CJS_Return(JSMessage::kNotSupportedError);
+  return CJS_Return::Failure(JSMessage::kNotSupportedError);
 }
 
 CJS_Return CJS_Event::get_field_full(CJS_Runtime* pRuntime) {
-  ASSERT(pRuntime->GetCurrentEventContext());
-
   CJS_EventHandler* pEvent =
       pRuntime->GetCurrentEventContext()->GetEventHandler();
-
   if (wcscmp((const wchar_t*)pEvent->Name(), L"Keystroke") != 0)
-    return CJS_Return(L"unrecognized event");
+    return CJS_Return::Failure(L"unrecognized event");
 
-  return CJS_Return(pRuntime->NewBoolean(pEvent->FieldFull()));
+  return CJS_Return::Success(pRuntime->NewBoolean(pEvent->FieldFull()));
 }
 
 CJS_Return CJS_Event::set_field_full(CJS_Runtime* pRuntime,
                                      v8::Local<v8::Value> vp) {
-  return CJS_Return(JSMessage::kNotSupportedError);
+  return CJS_Return::Failure(JSMessage::kNotSupportedError);
 }
 
 CJS_Return CJS_Event::get_key_down(CJS_Runtime* pRuntime) {
   CJS_EventHandler* pEvent =
       pRuntime->GetCurrentEventContext()->GetEventHandler();
-  return CJS_Return(pRuntime->NewBoolean(pEvent->KeyDown()));
+  return CJS_Return::Success(pRuntime->NewBoolean(pEvent->KeyDown()));
 }
 
 CJS_Return CJS_Event::set_key_down(CJS_Runtime* pRuntime,
                                    v8::Local<v8::Value> vp) {
-  return CJS_Return(JSMessage::kNotSupportedError);
+  return CJS_Return::Failure(JSMessage::kNotSupportedError);
 }
 
 CJS_Return CJS_Event::get_modifier(CJS_Runtime* pRuntime) {
   CJS_EventHandler* pEvent =
       pRuntime->GetCurrentEventContext()->GetEventHandler();
-  return CJS_Return(pRuntime->NewBoolean(pEvent->Modifier()));
+  return CJS_Return::Success(pRuntime->NewBoolean(pEvent->Modifier()));
 }
 
 CJS_Return CJS_Event::set_modifier(CJS_Runtime* pRuntime,
                                    v8::Local<v8::Value> vp) {
-  return CJS_Return(JSMessage::kNotSupportedError);
+  return CJS_Return::Failure(JSMessage::kNotSupportedError);
 }
 
 CJS_Return CJS_Event::get_name(CJS_Runtime* pRuntime) {
   CJS_EventHandler* pEvent =
       pRuntime->GetCurrentEventContext()->GetEventHandler();
-  return CJS_Return(pRuntime->NewString(pEvent->Name()));
+  return CJS_Return::Success(pRuntime->NewString(pEvent->Name()));
 }
 
 CJS_Return CJS_Event::set_name(CJS_Runtime* pRuntime, v8::Local<v8::Value> vp) {
-  return CJS_Return(JSMessage::kNotSupportedError);
+  return CJS_Return::Failure(JSMessage::kNotSupportedError);
 }
 
 CJS_Return CJS_Event::get_rc(CJS_Runtime* pRuntime) {
   CJS_EventHandler* pEvent =
       pRuntime->GetCurrentEventContext()->GetEventHandler();
-  return CJS_Return(pRuntime->NewBoolean(pEvent->Rc()));
+  return CJS_Return::Success(pRuntime->NewBoolean(pEvent->Rc()));
 }
 
 CJS_Return CJS_Event::set_rc(CJS_Runtime* pRuntime, v8::Local<v8::Value> vp) {
   CJS_EventHandler* pEvent =
       pRuntime->GetCurrentEventContext()->GetEventHandler();
   pEvent->Rc() = pRuntime->ToBoolean(vp);
-  return CJS_Return();
+  return CJS_Return::Success();
 }
 
 CJS_Return CJS_Event::get_rich_change(CJS_Runtime* pRuntime) {
-  return CJS_Return();
+  return CJS_Return::Success();
 }
 
 CJS_Return CJS_Event::set_rich_change(CJS_Runtime* pRuntime,
                                       v8::Local<v8::Value> vp) {
-  return CJS_Return();
+  return CJS_Return::Success();
 }
 
 CJS_Return CJS_Event::get_rich_change_ex(CJS_Runtime* pRuntime) {
-  return CJS_Return();
+  return CJS_Return::Success();
 }
 
 CJS_Return CJS_Event::set_rich_change_ex(CJS_Runtime* pRuntime,
                                          v8::Local<v8::Value> vp) {
-  return CJS_Return();
+  return CJS_Return::Success();
 }
 
 CJS_Return CJS_Event::get_rich_value(CJS_Runtime* pRuntime) {
-  return CJS_Return();
+  return CJS_Return::Success();
 }
 
 CJS_Return CJS_Event::set_rich_value(CJS_Runtime* pRuntime,
                                      v8::Local<v8::Value> vp) {
-  return CJS_Return();
+  return CJS_Return::Success();
 }
 
 CJS_Return CJS_Event::get_sel_end(CJS_Runtime* pRuntime) {
@@ -196,9 +189,9 @@ CJS_Return CJS_Event::get_sel_end(CJS_Runtime* pRuntime) {
       pRuntime->GetCurrentEventContext()->GetEventHandler();
 
   if (wcscmp((const wchar_t*)pEvent->Name(), L"Keystroke") != 0)
-    return CJS_Return();
+    return CJS_Return::Success();
 
-  return CJS_Return(pRuntime->NewNumber(pEvent->SelEnd()));
+  return CJS_Return::Success(pRuntime->NewNumber(pEvent->SelEnd()));
 }
 
 CJS_Return CJS_Event::set_sel_end(CJS_Runtime* pRuntime,
@@ -206,11 +199,10 @@ CJS_Return CJS_Event::set_sel_end(CJS_Runtime* pRuntime,
   CJS_EventHandler* pEvent =
       pRuntime->GetCurrentEventContext()->GetEventHandler();
 
-  if (wcscmp((const wchar_t*)pEvent->Name(), L"Keystroke") != 0)
-    return CJS_Return();
+  if (wcscmp((const wchar_t*)pEvent->Name(), L"Keystroke") == 0)
+    pEvent->SetSelEnd(pRuntime->ToInt32(vp));
 
-  pEvent->SetSelEnd(pRuntime->ToInt32(vp));
-  return CJS_Return();
+  return CJS_Return::Success();
 }
 
 CJS_Return CJS_Event::get_sel_start(CJS_Runtime* pRuntime) {
@@ -218,9 +210,9 @@ CJS_Return CJS_Event::get_sel_start(CJS_Runtime* pRuntime) {
       pRuntime->GetCurrentEventContext()->GetEventHandler();
 
   if (wcscmp((const wchar_t*)pEvent->Name(), L"Keystroke") != 0)
-    return CJS_Return();
+    return CJS_Return::Success();
 
-  return CJS_Return(pRuntime->NewNumber(pEvent->SelStart()));
+  return CJS_Return::Success(pRuntime->NewNumber(pEvent->SelStart()));
 }
 
 CJS_Return CJS_Event::set_sel_start(CJS_Runtime* pRuntime,
@@ -228,84 +220,81 @@ CJS_Return CJS_Event::set_sel_start(CJS_Runtime* pRuntime,
   CJS_EventHandler* pEvent =
       pRuntime->GetCurrentEventContext()->GetEventHandler();
 
-  if (wcscmp((const wchar_t*)pEvent->Name(), L"Keystroke") != 0)
-    return CJS_Return();
+  if (wcscmp((const wchar_t*)pEvent->Name(), L"Keystroke") == 0)
+    pEvent->SetSelStart(pRuntime->ToInt32(vp));
 
-  pEvent->SetSelStart(pRuntime->ToInt32(vp));
-  return CJS_Return();
+  return CJS_Return::Success();
 }
 
 CJS_Return CJS_Event::get_shift(CJS_Runtime* pRuntime) {
   CJS_EventHandler* pEvent =
       pRuntime->GetCurrentEventContext()->GetEventHandler();
-  return CJS_Return(pRuntime->NewBoolean(pEvent->Shift()));
+  return CJS_Return::Success(pRuntime->NewBoolean(pEvent->Shift()));
 }
 
 CJS_Return CJS_Event::set_shift(CJS_Runtime* pRuntime,
                                 v8::Local<v8::Value> vp) {
-  return CJS_Return(JSMessage::kNotSupportedError);
+  return CJS_Return::Failure(JSMessage::kNotSupportedError);
 }
 
 CJS_Return CJS_Event::get_source(CJS_Runtime* pRuntime) {
   CJS_EventHandler* pEvent =
       pRuntime->GetCurrentEventContext()->GetEventHandler();
-  return CJS_Return(pEvent->Source()->ToV8Object());
+  return CJS_Return::Success(pEvent->Source()->ToV8Object());
 }
 
 CJS_Return CJS_Event::set_source(CJS_Runtime* pRuntime,
                                  v8::Local<v8::Value> vp) {
-  return CJS_Return(JSMessage::kNotSupportedError);
+  return CJS_Return::Failure(JSMessage::kNotSupportedError);
 }
 
 CJS_Return CJS_Event::get_target(CJS_Runtime* pRuntime) {
   ASSERT(pRuntime->GetCurrentEventContext());
   CJS_EventHandler* pEvent =
       pRuntime->GetCurrentEventContext()->GetEventHandler();
-  return CJS_Return(pEvent->Target_Field()->ToV8Object());
+  return CJS_Return::Success(pEvent->Target_Field()->ToV8Object());
 }
 
 CJS_Return CJS_Event::set_target(CJS_Runtime* pRuntime,
                                  v8::Local<v8::Value> vp) {
-  return CJS_Return(JSMessage::kNotSupportedError);
+  return CJS_Return::Failure(JSMessage::kNotSupportedError);
 }
 
 CJS_Return CJS_Event::get_target_name(CJS_Runtime* pRuntime) {
   ASSERT(pRuntime->GetCurrentEventContext());
   CJS_EventHandler* pEvent =
       pRuntime->GetCurrentEventContext()->GetEventHandler();
-  return CJS_Return(pRuntime->NewString(pEvent->TargetName().AsStringView()));
+  return CJS_Return::Success(
+      pRuntime->NewString(pEvent->TargetName().AsStringView()));
 }
 
 CJS_Return CJS_Event::set_target_name(CJS_Runtime* pRuntime,
                                       v8::Local<v8::Value> vp) {
-  return CJS_Return(JSMessage::kNotSupportedError);
+  return CJS_Return::Failure(JSMessage::kNotSupportedError);
 }
 
 CJS_Return CJS_Event::get_type(CJS_Runtime* pRuntime) {
-  ASSERT(pRuntime->GetCurrentEventContext());
-
   CJS_EventHandler* pEvent =
       pRuntime->GetCurrentEventContext()->GetEventHandler();
-  return CJS_Return(pRuntime->NewString(pEvent->Type()));
+  return CJS_Return::Success(pRuntime->NewString(pEvent->Type()));
 }
 
 CJS_Return CJS_Event::set_type(CJS_Runtime* pRuntime, v8::Local<v8::Value> vp) {
-  return CJS_Return(JSMessage::kNotSupportedError);
+  return CJS_Return::Failure(JSMessage::kNotSupportedError);
 }
 
 CJS_Return CJS_Event::get_value(CJS_Runtime* pRuntime) {
-  ASSERT(pRuntime->GetCurrentEventContext());
-
   CJS_EventHandler* pEvent =
       pRuntime->GetCurrentEventContext()->GetEventHandler();
 
   if (wcscmp((const wchar_t*)pEvent->Type(), L"Field") != 0)
-    return CJS_Return(L"Bad event type.");
+    return CJS_Return::Failure(L"Bad event type.");
 
   if (!pEvent->m_pValue)
-    return CJS_Return(JSMessage::kBadObjectError);
+    return CJS_Return::Failure(JSMessage::kBadObjectError);
 
-  return CJS_Return(pRuntime->NewString(pEvent->Value().AsStringView()));
+  return CJS_Return::Success(
+      pRuntime->NewString(pEvent->Value().AsStringView()));
 }
 
 CJS_Return CJS_Event::set_value(CJS_Runtime* pRuntime,
@@ -316,13 +305,13 @@ CJS_Return CJS_Event::set_value(CJS_Runtime* pRuntime,
       pRuntime->GetCurrentEventContext()->GetEventHandler();
 
   if (wcscmp((const wchar_t*)pEvent->Type(), L"Field") != 0)
-    return CJS_Return(L"Bad event type.");
+    return CJS_Return::Failure(L"Bad event type.");
 
   if (!pEvent->m_pValue)
-    return CJS_Return(JSMessage::kBadObjectError);
+    return CJS_Return::Failure(JSMessage::kBadObjectError);
 
   pEvent->Value() = pRuntime->ToWideString(vp);
-  return CJS_Return();
+  return CJS_Return::Success();
 }
 
 CJS_Return CJS_Event::get_will_commit(CJS_Runtime* pRuntime) {
@@ -330,10 +319,10 @@ CJS_Return CJS_Event::get_will_commit(CJS_Runtime* pRuntime) {
 
   CJS_EventHandler* pEvent =
       pRuntime->GetCurrentEventContext()->GetEventHandler();
-  return CJS_Return(pRuntime->NewBoolean(pEvent->WillCommit()));
+  return CJS_Return::Success(pRuntime->NewBoolean(pEvent->WillCommit()));
 }
 
 CJS_Return CJS_Event::set_will_commit(CJS_Runtime* pRuntime,
                                       v8::Local<v8::Value> vp) {
-  return CJS_Return(JSMessage::kNotSupportedError);
+  return CJS_Return::Failure(JSMessage::kNotSupportedError);
 }