Convert string Find methods to return an Optional

The Find and ReverseFind methods for WideString, WideStringC,
ByteString, and ByteStringC have been converted from returning a raw
FX_STRSIZE, to returning Optional<FX_STRSIZE>, so that success/failure
can be indicated without using FX_STRNPOS.

This allows for removing FX_STRNPOS and by association makes the
conversion of FX_STRSIZE to size_t easier, since it forces checking
the return value of Find to be explictly done as well as taking the
error value out of the range of FX_STRSIZE.

New Contains methods have been added for cases where the success or
failure is all the call site to Find cared about, and the actual
position was ignored.

BUG=pdfium:828


Change-Id: Id827e508c8660affa68cc08a13d96121369364b7
Reviewed-on: https://pdfium-review.googlesource.com/11350
Commit-Queue: Ryan Harrison <rharrison@chromium.org>
Reviewed-by: dsinclair <dsinclair@chromium.org>

1 files changed, 9 insertions, 9 deletions

diff --git a/xfa/fxfa/parser/cxfa_localevalue.cpp b/xfa/fxfa/parser/cxfa_localevalue.cpp
index aa0f74b170..dd56e6d7a1 100644
--- a/xfa/fxfa/parser/cxfa_localevalue.cpp
+++ b/xfa/fxfa/parser/cxfa_localevalue.cpp
@@ -49,14 +49,14 @@ bool ValueSplitDateTime(const CFX_WideString& wsDateTime,
   if (wsDateTime.IsEmpty())
     return false;
 
-  FX_STRSIZE nSplitIndex = wsDateTime.Find('T');
-  if (nSplitIndex == FX_STRNPOS)
+  auto nSplitIndex = wsDateTime.Find('T');
+  if (!nSplitIndex.has_value())
     nSplitIndex = wsDateTime.Find(' ');
-  if (nSplitIndex == FX_STRNPOS)
+  if (!nSplitIndex.has_value())
     return false;
 
-  wsDate = wsDateTime.Left(nSplitIndex);
-  wsTime = wsDateTime.Right(wsDateTime.GetLength() - nSplitIndex - 1);
+  wsDate = wsDateTime.Left(nSplitIndex.value());
+  wsTime = wsDateTime.Right(wsDateTime.GetLength() - nSplitIndex.value() - 1);
   return true;
 }
 
@@ -444,7 +444,7 @@ bool CXFA_LocaleValue::ValidateCanonicalDate(const CFX_WideString& wsDate,
   if (nLen < wCountY || nLen > wCountY + wCountM + wCountD + 2)
     return false;
 
-  const bool bSymbol = wsDate.Find(0x2D) != FX_STRNPOS;
+  const bool bSymbol = wsDate.Contains(0x2D);
   uint16_t wYear = 0;
   uint16_t wMonth = 0;
   uint16_t wDay = 0;
@@ -519,7 +519,7 @@ bool CXFA_LocaleValue::ValidateCanonicalTime(const CFX_WideString& wsTime) {
   const uint16_t wCountM = 2;
   const uint16_t wCountS = 2;
   const uint16_t wCountF = 3;
-  const bool bSymbol = wsTime.Find(':') != FX_STRNPOS;
+  const bool bSymbol = wsTime.Contains(':');
   uint16_t wHour = 0;
   uint16_t wMinute = 0;
   uint16_t wSecond = 0;
@@ -558,8 +558,8 @@ bool CXFA_LocaleValue::ValidateCanonicalTime(const CFX_WideString& wsTime) {
     wSecond = pTime[nIndex] - '0' + wSecond * 10;
     nIndex++;
   }
-  FX_STRSIZE ret = wsTime.Find('.');
-  if (ret && ret != FX_STRNPOS) {
+  auto pos = wsTime.Find('.');
+  if (pos.has_value() && pos.value() != 0) {
     if (pTime[nIndex] != '.')
       return false;
     nIndex++;