Re-work some more c_str() usage.

Many of these are converting ByteString => c_str => ByteStringView, since
the ByteStringView ctor is implicit. This is unfortunate, since that
involves a strlen() which the ByteString already knows if we use
AsStringView() instead.

This changed one test result where we can now return the string
"\0" instead of "" -- since strlen no longer eats the NUL. This
seems consistent, say, with String.fromCharCode().

Change-Id: I17f68d1a1f4b352960208f9148e68ab4c4d78bd2
Reviewed-on: https://pdfium-review.googlesource.com/35590
Reviewed-by: dsinclair <dsinclair@chromium.org>
Commit-Queue: Tom Sepez <tsepez@chromium.org>

9 files changed, 65 insertions, 63 deletions

diff --git a/fxjs/cjs_annot.cpp b/fxjs/cjs_annot.cpp
index 8a53ebc048..49db20475a 100644
--- a/fxjs/cjs_annot.cpp
+++ b/fxjs/cjs_annot.cpp
@@ -81,8 +81,8 @@ CJS_Return CJS_Annot::set_hidden(CJS_Runtime* pRuntime,
 CJS_Return CJS_Annot::get_name(CJS_Runtime* pRuntime) {
   if (!m_pAnnot)
     return CJS_Return(JSMessage::kBadObjectError);
-  return CJS_Return(
-      pRuntime->NewString(ToBAAnnot(m_pAnnot.Get())->GetAnnotName().c_str()));
+  return CJS_Return(pRuntime->NewString(
+      ToBAAnnot(m_pAnnot.Get())->GetAnnotName().AsStringView()));
 }
 
 CJS_Return CJS_Annot::set_name(CJS_Runtime* pRuntime, v8::Local<v8::Value> vp) {
@@ -101,8 +101,8 @@ CJS_Return CJS_Annot::get_type(CJS_Runtime* pRuntime) {
   return CJS_Return(pRuntime->NewString(
       WideString::FromLocal(CPDF_Annot::AnnotSubtypeToString(
                                 ToBAAnnot(m_pAnnot.Get())->GetAnnotSubtype())
-                                .c_str())
-          .c_str()));
+                                .AsStringView())
+          .AsStringView()));
 }
 
 CJS_Return CJS_Annot::set_type(CJS_Runtime* pRuntime, v8::Local<v8::Value> vp) {
diff --git a/fxjs/cjs_app.cpp b/fxjs/cjs_app.cpp
index 61eb632939..36a1212715 100644
--- a/fxjs/cjs_app.cpp
+++ b/fxjs/cjs_app.cpp
@@ -176,9 +176,9 @@ CJS_Return CJS_App::get_platform(CJS_Runtime* pRuntime) {
   if (!pFormFillEnv)
     return CJS_Return(JSMessage::kBadObjectError);
 
-  WideString platfrom = pFormFillEnv->GetPlatform();
-  if (!platfrom.IsEmpty())
-    return CJS_Return(pRuntime->NewString(platfrom.c_str()));
+  WideString platform = pFormFillEnv->GetPlatform();
+  if (!platform.IsEmpty())
+    return CJS_Return(pRuntime->NewString(platform.AsStringView()));
 #endif
   return CJS_Return(pRuntime->NewString(JS_STR_PLATFORM));
 }
@@ -196,7 +196,7 @@ CJS_Return CJS_App::get_language(CJS_Runtime* pRuntime) {
 
   WideString language = pFormFillEnv->GetLanguage();
   if (!language.IsEmpty())
-    return CJS_Return(pRuntime->NewString(language.c_str()));
+    return CJS_Return(pRuntime->NewString(language.AsStringView()));
 #endif
   return CJS_Return(pRuntime->NewString(JS_STR_LANGUAGE));
 }
@@ -572,7 +572,7 @@ CJS_Return CJS_App::response(CJS_Runtime* pRuntime,
   return CJS_Return(pRuntime->NewString(
       WideString::FromUTF16LE(reinterpret_cast<uint16_t*>(pBuff.data()),
                               nLengthBytes / sizeof(uint16_t))
-          .c_str()));
+          .AsStringView()));
 }
 
 CJS_Return CJS_App::get_media(CJS_Runtime* pRuntime) {
diff --git a/fxjs/cjs_document.cpp b/fxjs/cjs_document.cpp
index 74304bba1d..b22d31b0b4 100644
--- a/fxjs/cjs_document.cpp
+++ b/fxjs/cjs_document.cpp
@@ -279,7 +279,7 @@ CJS_Return CJS_Document::getNthFieldName(
   CPDF_FormField* pField = pPDFForm->GetField(nIndex, WideString());
   if (!pField)
     return CJS_Return(JSMessage::kBadObjectError);
-  return CJS_Return(pRuntime->NewString(pField->GetFullName().c_str()));
+  return CJS_Return(pRuntime->NewString(pField->GetFullName().AsStringView()));
 }
 
 CJS_Return CJS_Document::importAnFDF(
@@ -719,8 +719,8 @@ CJS_Return CJS_Document::getPropertyInternal(CJS_Runtime* pRuntime,
   CPDF_Dictionary* pDictionary = m_pFormFillEnv->GetPDFDocument()->GetInfo();
   if (!pDictionary)
     return CJS_Return(JSMessage::kBadObjectError);
-  return CJS_Return(
-      pRuntime->NewString(pDictionary->GetUnicodeTextFor(propName).c_str()));
+  return CJS_Return(pRuntime->NewString(
+      pDictionary->GetUnicodeTextFor(propName).AsStringView()));
 }
 
 CJS_Return CJS_Document::setPropertyInternal(CJS_Runtime* pRuntime,
@@ -889,7 +889,7 @@ CJS_Return CJS_Document::get_URL(CJS_Runtime* pRuntime) {
   if (!m_pFormFillEnv)
     return CJS_Return(JSMessage::kBadObjectError);
   return CJS_Return(
-      pRuntime->NewString(m_pFormFillEnv->JS_docGetFilePath().c_str()));
+      pRuntime->NewString(m_pFormFillEnv->JS_docGetFilePath().AsStringView()));
 }
 
 CJS_Return CJS_Document::set_URL(CJS_Runtime* pRuntime,
@@ -898,7 +898,7 @@ CJS_Return CJS_Document::set_URL(CJS_Runtime* pRuntime,
 }
 
 CJS_Return CJS_Document::get_base_URL(CJS_Runtime* pRuntime) {
-  return CJS_Return(pRuntime->NewString(m_cwBaseURL.c_str()));
+  return CJS_Return(pRuntime->NewString(m_cwBaseURL.AsStringView()));
 }
 
 CJS_Return CJS_Document::set_base_URL(CJS_Runtime* pRuntime,
@@ -950,7 +950,8 @@ CJS_Return CJS_Document::get_path(CJS_Runtime* pRuntime) {
   if (!m_pFormFillEnv)
     return CJS_Return(JSMessage::kBadObjectError);
   return CJS_Return(pRuntime->NewString(
-      CJS_App::SysPathToPDFPath(m_pFormFillEnv->JS_docGetFilePath()).c_str()));
+      CJS_App::SysPathToPDFPath(m_pFormFillEnv->JS_docGetFilePath())
+          .AsStringView()));
 }
 
 CJS_Return CJS_Document::set_path(CJS_Runtime* pRuntime,
@@ -1269,7 +1270,7 @@ CJS_Return CJS_Document::getPageNthWord(
 
   if (bStrip)
     swRet.Trim();
-  return CJS_Return(pRuntime->NewString(swRet.c_str()));
+  return CJS_Return(pRuntime->NewString(swRet.AsStringView()));
 }
 
 CJS_Return CJS_Document::getPageNthWordQuads(
diff --git a/fxjs/cjs_event.cpp b/fxjs/cjs_event.cpp
index 397d8b890c..c10f8858a9 100644
--- a/fxjs/cjs_event.cpp
+++ b/fxjs/cjs_event.cpp
@@ -51,10 +51,9 @@ 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().c_str()));
+  return CJS_Return(pRuntime->NewString(pEvent->Change().AsStringView()));
 }
 
 CJS_Return CJS_Event::set_change(CJS_Runtime* pRuntime,
@@ -73,11 +72,10 @@ CJS_Return CJS_Event::set_change(CJS_Runtime* pRuntime,
 
 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().c_str()));
+  return CJS_Return(pRuntime->NewString(pEvent->ChangeEx().AsStringView()));
 }
 
 CJS_Return CJS_Event::set_change_ex(CJS_Runtime* pRuntime,
@@ -256,7 +254,6 @@ CJS_Return CJS_Event::set_source(CJS_Runtime* pRuntime,
 
 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());
@@ -269,10 +266,9 @@ CJS_Return CJS_Event::set_target(CJS_Runtime* pRuntime,
 
 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().c_str()));
+  return CJS_Return(pRuntime->NewString(pEvent->TargetName().AsStringView()));
 }
 
 CJS_Return CJS_Event::set_target_name(CJS_Runtime* pRuntime,
@@ -304,7 +300,7 @@ CJS_Return CJS_Event::get_value(CJS_Runtime* pRuntime) {
   if (!pEvent->m_pValue)
     return CJS_Return(JSMessage::kBadObjectError);
 
-  return CJS_Return(pRuntime->NewString(pEvent->Value().c_str()));
+  return CJS_Return(pRuntime->NewString(pEvent->Value().AsStringView()));
 }
 
 CJS_Return CJS_Event::set_value(CJS_Runtime* pRuntime,
diff --git a/fxjs/cjs_field.cpp b/fxjs/cjs_field.cpp
index e9aa777df8..84835866ea 100644
--- a/fxjs/cjs_field.cpp
+++ b/fxjs/cjs_field.cpp
@@ -890,7 +890,8 @@ CJS_Return CJS_Field::get_default_value(CJS_Runtime* pRuntime) {
     return CJS_Return(JSMessage::kObjectTypeError);
   }
 
-  return CJS_Return(pRuntime->NewString(pFormField->GetDefaultValue().c_str()));
+  return CJS_Return(
+      pRuntime->NewString(pFormField->GetDefaultValue().AsStringView()));
 }
 
 CJS_Return CJS_Field::set_default_value(CJS_Runtime* pRuntime,
@@ -1092,7 +1093,7 @@ CJS_Return CJS_Field::get_export_values(CJS_Runtime* pRuntime) {
       CPDF_FormControl* pFormControl = pFormField->GetControl(i);
       pRuntime->PutArrayElement(
           ExportValuesArray, i,
-          pRuntime->NewString(pFormControl->GetExportValue().c_str()));
+          pRuntime->NewString(pFormControl->GetExportValue().AsStringView()));
     }
   } else {
     if (m_nFormControlIndex >= pFormField->CountControls())
@@ -1105,7 +1106,7 @@ CJS_Return CJS_Field::get_export_values(CJS_Runtime* pRuntime) {
 
     pRuntime->PutArrayElement(
         ExportValuesArray, 0,
-        pRuntime->NewString(pFormControl->GetExportValue().c_str()));
+        pRuntime->NewString(pFormControl->GetExportValue().AsStringView()));
   }
   return CJS_Return(ExportValuesArray);
 }
@@ -1420,7 +1421,7 @@ CJS_Return CJS_Field::get_name(CJS_Runtime* pRuntime) {
   if (FieldArray.empty())
     return CJS_Return(JSMessage::kBadObjectError);
 
-  return CJS_Return(pRuntime->NewString(m_FieldName.c_str()));
+  return CJS_Return(pRuntime->NewString(m_FieldName.AsStringView()));
 }
 
 CJS_Return CJS_Field::set_name(CJS_Runtime* pRuntime, v8::Local<v8::Value> vp) {
@@ -1903,8 +1904,8 @@ CJS_Return CJS_Field::get_style(CJS_Runtime* pRuntime) {
       csBCaption = "check";
       break;
   }
-  return CJS_Return(
-      pRuntime->NewString(WideString::FromLocal(csBCaption.c_str()).c_str()));
+  return CJS_Return(pRuntime->NewString(
+      WideString::FromLocal(csBCaption.AsStringView()).AsStringView()));
 }
 
 CJS_Return CJS_Field::set_style(CJS_Runtime* pRuntime,
@@ -1993,7 +1994,8 @@ CJS_Return CJS_Field::get_text_font(CJS_Runtime* pRuntime) {
     return CJS_Return(JSMessage::kBadObjectError);
 
   return CJS_Return(pRuntime->NewString(
-      WideString::FromLocal(pFont->GetBaseFont().c_str()).c_str()));
+      WideString::FromLocal(pFont->GetBaseFont().AsStringView())
+          .AsStringView()));
 }
 
 CJS_Return CJS_Field::set_text_font(CJS_Runtime* pRuntime,
@@ -2074,7 +2076,7 @@ CJS_Return CJS_Field::get_user_name(CJS_Runtime* pRuntime) {
     return CJS_Return(JSMessage::kBadObjectError);
 
   return CJS_Return(
-      pRuntime->NewString(FieldArray[0]->GetAlternateName().c_str()));
+      pRuntime->NewString(FieldArray[0]->GetAlternateName().AsStringView()));
 }
 
 CJS_Return CJS_Field::set_user_name(CJS_Runtime* pRuntime,
@@ -2098,7 +2100,7 @@ CJS_Return CJS_Field::get_value(CJS_Runtime* pRuntime) {
       return CJS_Return(JSMessage::kObjectTypeError);
     case FormFieldType::kComboBox:
     case FormFieldType::kTextField:
-      ret = pRuntime->NewString(pFormField->GetValue().c_str());
+      ret = pRuntime->NewString(pFormField->GetValue().AsStringView());
       break;
     case FormFieldType::kListBox: {
       if (pFormField->CountSelectedItems() > 1) {
@@ -2107,17 +2109,17 @@ CJS_Return CJS_Field::get_value(CJS_Runtime* pRuntime) {
         int iIndex;
         for (int i = 0, sz = pFormField->CountSelectedItems(); i < sz; i++) {
           iIndex = pFormField->GetSelectedIndex(i);
-          ElementValue =
-              pRuntime->NewString(pFormField->GetOptionValue(iIndex).c_str());
+          ElementValue = pRuntime->NewString(
+              pFormField->GetOptionValue(iIndex).AsStringView());
           if (wcslen(pRuntime->ToWideString(ElementValue).c_str()) == 0) {
-            ElementValue =
-                pRuntime->NewString(pFormField->GetOptionLabel(iIndex).c_str());
+            ElementValue = pRuntime->NewString(
+                pFormField->GetOptionLabel(iIndex).AsStringView());
           }
           pRuntime->PutArrayElement(ValueArray, i, ElementValue);
         }
         ret = ValueArray;
       } else {
-        ret = pRuntime->NewString(pFormField->GetValue().c_str());
+        ret = pRuntime->NewString(pFormField->GetValue().AsStringView());
       }
       break;
     }
@@ -2127,7 +2129,7 @@ CJS_Return CJS_Field::get_value(CJS_Runtime* pRuntime) {
       for (int i = 0, sz = pFormField->CountControls(); i < sz; i++) {
         if (pFormField->GetControl(i)->IsChecked()) {
           ret = pRuntime->NewString(
-              pFormField->GetControl(i)->GetExportValue().c_str());
+              pFormField->GetControl(i)->GetExportValue().AsStringView());
           bFind = true;
           break;
         }
@@ -2138,7 +2140,7 @@ CJS_Return CJS_Field::get_value(CJS_Runtime* pRuntime) {
       break;
     }
     default:
-      ret = pRuntime->NewString(pFormField->GetValue().c_str());
+      ret = pRuntime->NewString(pFormField->GetValue().AsStringView());
       break;
   }
   return CJS_Return(pRuntime->MaybeCoerceToNumber(ret));
@@ -2245,7 +2247,7 @@ CJS_Return CJS_Field::get_value_as_string(CJS_Runtime* pRuntime) {
     for (int i = 0, sz = pFormField->CountControls(); i < sz; i++) {
       if (pFormField->GetControl(i)->IsChecked()) {
         return CJS_Return(pRuntime->NewString(
-            pFormField->GetControl(i)->GetExportValue().c_str()));
+            pFormField->GetControl(i)->GetExportValue().AsStringView()));
       }
     }
     return CJS_Return(pRuntime->NewString(L"Off"));
@@ -2255,7 +2257,7 @@ CJS_Return CJS_Field::get_value_as_string(CJS_Runtime* pRuntime) {
       (pFormField->CountSelectedItems() > 1)) {
     return CJS_Return(pRuntime->NewString(L""));
   }
-  return CJS_Return(pRuntime->NewString(pFormField->GetValue().c_str()));
+  return CJS_Return(pRuntime->NewString(pFormField->GetValue().AsStringView()));
 }
 
 CJS_Return CJS_Field::set_value_as_string(CJS_Runtime* pRuntime,
@@ -2305,13 +2307,15 @@ CJS_Return CJS_Field::buttonGetCaption(
 
   if (nface == 0) {
     return CJS_Return(
-        pRuntime->NewString(pFormControl->GetNormalCaption().c_str()));
-  } else if (nface == 1) {
+        pRuntime->NewString(pFormControl->GetNormalCaption().AsStringView()));
+  }
+  if (nface == 1) {
     return CJS_Return(
-        pRuntime->NewString(pFormControl->GetDownCaption().c_str()));
-  } else if (nface == 2) {
+        pRuntime->NewString(pFormControl->GetDownCaption().AsStringView()));
+  }
+  if (nface == 2) {
     return CJS_Return(
-        pRuntime->NewString(pFormControl->GetRolloverCaption().c_str()));
+        pRuntime->NewString(pFormControl->GetRolloverCaption().AsStringView()));
   }
   return CJS_Return(JSMessage::kValueError);
 }
@@ -2496,13 +2500,13 @@ CJS_Return CJS_Field::getItemAt(
     if (bExport) {
       WideString strval = pFormField->GetOptionValue(nIdx);
       if (strval.IsEmpty()) {
-        return CJS_Return(
-            pRuntime->NewString(pFormField->GetOptionLabel(nIdx).c_str()));
+        return CJS_Return(pRuntime->NewString(
+            pFormField->GetOptionLabel(nIdx).AsStringView()));
       }
-      return CJS_Return(pRuntime->NewString(strval.c_str()));
+      return CJS_Return(pRuntime->NewString(strval.AsStringView()));
     }
     return CJS_Return(
-        pRuntime->NewString(pFormField->GetOptionLabel(nIdx).c_str()));
+        pRuntime->NewString(pFormField->GetOptionLabel(nIdx).AsStringView()));
   }
   return CJS_Return(JSMessage::kObjectTypeError);
 }
diff --git a/fxjs/cjs_global.cpp b/fxjs/cjs_global.cpp
index 977d916492..e9b2a4b8f0 100644
--- a/fxjs/cjs_global.cpp
+++ b/fxjs/cjs_global.cpp
@@ -248,7 +248,7 @@ CJS_Return CJS_Global::GetProperty(CJS_Runtime* pRuntime,
       return CJS_Return(pRuntime->NewBoolean(pData->bData));
     case JS_GlobalDataType::STRING:
       return CJS_Return(pRuntime->NewString(
-          WideString::FromLocal(pData->sData.c_str()).c_str()));
+          WideString::FromLocal(pData->sData.AsStringView()).AsStringView()));
     case JS_GlobalDataType::OBJECT:
       return CJS_Return(
           v8::Local<v8::Object>::New(pRuntime->GetIsolate(), pData->pData));
diff --git a/fxjs/cjs_icon.cpp b/fxjs/cjs_icon.cpp
index 9cf20feb73..3c293ea969 100644
--- a/fxjs/cjs_icon.cpp
+++ b/fxjs/cjs_icon.cpp
@@ -30,7 +30,7 @@ CJS_Icon::CJS_Icon(v8::Local<v8::Object> pObject, CJS_Runtime* pRuntime)
 CJS_Icon::~CJS_Icon() = default;
 
 CJS_Return CJS_Icon::get_name(CJS_Runtime* pRuntime) {
-  return CJS_Return(pRuntime->NewString(m_swIconName.c_str()));
+  return CJS_Return(pRuntime->NewString(m_swIconName.AsStringView()));
 }
 
 CJS_Return CJS_Icon::set_name(CJS_Runtime* pRuntime, v8::Local<v8::Value> vp) {
diff --git a/fxjs/cjs_publicmethods.cpp b/fxjs/cjs_publicmethods.cpp
index 4630445a35..2bc68fa6d3 100644
--- a/fxjs/cjs_publicmethods.cpp
+++ b/fxjs/cjs_publicmethods.cpp
@@ -336,13 +336,13 @@ v8::Local<v8::Array> CJS_PublicMethods::AF_MakeArrayFromList(
     if (!pTemp) {
       pRuntime->PutArrayElement(
           StrArray, nIndex,
-          pRuntime->NewString(StrTrim(ByteString(p)).c_str()));
+          pRuntime->NewString(StrTrim(ByteString(p)).AsStringView()));
       break;
     }
 
     pRuntime->PutArrayElement(
         StrArray, nIndex,
-        pRuntime->NewString(StrTrim(ByteString(p, pTemp - p)).c_str()));
+        pRuntime->NewString(StrTrim(ByteString(p, pTemp - p)).AsStringView()));
 
     nIndex++;
     p = ++pTemp;
@@ -1525,11 +1525,11 @@ CJS_Return CJS_PublicMethods::AFMergeChange(
     swValue = pEventHandler->Value();
 
   if (pEventHandler->WillCommit())
-    return CJS_Return(pRuntime->NewString(swValue.c_str()));
+    return CJS_Return(pRuntime->NewString(swValue.AsStringView()));
 
   WideString merged =
       CalcMergedString(pEventHandler, swValue, pEventHandler->Change());
-  return CJS_Return(pRuntime->NewString(merged.c_str()));
+  return CJS_Return(pRuntime->NewString(merged.AsStringView()));
 }
 
 CJS_Return CJS_PublicMethods::AFParseDateEx(
@@ -1571,7 +1571,7 @@ CJS_Return CJS_PublicMethods::AFMakeNumber(
   NormalizeDecimalMarkW(&ws);
 
   v8::Local<v8::Value> val =
-      pRuntime->MaybeCoerceToNumber(pRuntime->NewString(ws.c_str()));
+      pRuntime->MaybeCoerceToNumber(pRuntime->NewString(ws.AsStringView()));
   if (!val->IsNumber())
     return CJS_Return(pRuntime->NewNumber(0));
   return CJS_Return(val);
@@ -1734,14 +1734,15 @@ CJS_Return CJS_PublicMethods::AFExtractNums(
       sPart += wc;
     } else if (sPart.GetLength() > 0) {
       pRuntime->PutArrayElement(nums, nIndex,
-                                pRuntime->NewString(sPart.c_str()));
+                                pRuntime->NewString(sPart.AsStringView()));
       sPart.clear();
       nIndex++;
     }
   }
-  if (sPart.GetLength() > 0)
-    pRuntime->PutArrayElement(nums, nIndex, pRuntime->NewString(sPart.c_str()));
-
+  if (sPart.GetLength() > 0) {
+    pRuntime->PutArrayElement(nums, nIndex,
+                              pRuntime->NewString(sPart.AsStringView()));
+  }
   if (pRuntime->GetArrayLength(nums) > 0)
     return CJS_Return(nums);
   return CJS_Return(pRuntime->NewUndefined());
diff --git a/fxjs/cjs_util.cpp b/fxjs/cjs_util.cpp
index 576a85b999..fec727302d 100644
--- a/fxjs/cjs_util.cpp
+++ b/fxjs/cjs_util.cpp
@@ -387,7 +387,7 @@ CJS_Return CJS_Util::byteToChar(
     return CJS_Return(JSMessage::kValueError);
 
   WideString wStr(static_cast<wchar_t>(arg));
-  return CJS_Return(pRuntime->NewString(wStr.c_str()));
+  return CJS_Return(pRuntime->NewString(wStr.AsStringView()));
 }
 
 // Ensure that sFormat contains at most one well-understood printf formatting