Add unit test for CXFA_FileRead.

The FileRead's return convention is being modified at
https://codereview.chromium.org/2430743003/, so first provide
a test of the old behaviour.

Fix some issues with null dictionaries as provided by the
CPDF_Stream default ctor along the way.

Review-Url: https://codereview.chromium.org/2517513003

3 files changed, 13 insertions, 12 deletions

diff --git a/core/fpdfapi/parser/cpdf_stream.cpp b/core/fpdfapi/parser/cpdf_stream.cpp
index e8ee022940..64261b14d3 100644
--- a/core/fpdfapi/parser/cpdf_stream.cpp
+++ b/core/fpdfapi/parser/cpdf_stream.cpp
@@ -113,6 +113,10 @@ bool CPDF_Stream::ReadRawData(FX_FILESIZE offset,
   return true;
 }
 
+bool CPDF_Stream::HasFilter() const {
+  return m_pDict && m_pDict->KeyExist("Filter");
+}
+
 CFX_WideString CPDF_Stream::GetUnicodeText() const {
   CPDF_StreamAcc stream;
   stream.LoadAllData(this, false);
diff --git a/core/fpdfapi/parser/cpdf_stream.h b/core/fpdfapi/parser/cpdf_stream.h
index ddf7cc5b69..c4f9aacf2b 100644
--- a/core/fpdfapi/parser/cpdf_stream.h
+++ b/core/fpdfapi/parser/cpdf_stream.h
@@ -46,6 +46,7 @@ class CPDF_Stream : public CPDF_Object {
                    uint32_t buf_size) const;
 
   bool IsMemoryBased() const { return m_bMemoryBased; }
+  bool HasFilter() const;
 
  protected:
   std::unique_ptr<CPDF_Object> CloneNonCyclic(
diff --git a/core/fpdfapi/parser/cpdf_stream_acc.cpp b/core/fpdfapi/parser/cpdf_stream_acc.cpp
index 81439bc677..01d8e148df 100644
--- a/core/fpdfapi/parser/cpdf_stream_acc.cpp
+++ b/core/fpdfapi/parser/cpdf_stream_acc.cpp
@@ -24,17 +24,16 @@ void CPDF_StreamAcc::LoadAllData(const CPDF_Stream* pStream,
     return;
 
   m_pStream = pStream;
-  if (pStream->IsMemoryBased() &&
-      (!pStream->GetDict()->KeyExist("Filter") || bRawAccess)) {
+  if (pStream->IsMemoryBased() && (!pStream->HasFilter() || bRawAccess)) {
     m_dwSize = pStream->GetRawSize();
     m_pData = pStream->GetRawData();
     return;
   }
-  uint8_t* pSrcData;
   uint32_t dwSrcSize = pStream->GetRawSize();
   if (dwSrcSize == 0)
     return;
 
+  uint8_t* pSrcData;
   if (!pStream->IsMemoryBased()) {
     pSrcData = m_pSrcData = FX_Alloc(uint8_t, dwSrcSize);
     if (!pStream->ReadRawData(0, pSrcData, dwSrcSize))
@@ -42,17 +41,14 @@ void CPDF_StreamAcc::LoadAllData(const CPDF_Stream* pStream,
   } else {
     pSrcData = pStream->GetRawData();
   }
-  if (!pStream->GetDict()->KeyExist("Filter") || bRawAccess) {
+  if (!pStream->HasFilter() || bRawAccess) {
+    m_pData = pSrcData;
+    m_dwSize = dwSrcSize;
+  } else if (!PDF_DataDecode(pSrcData, dwSrcSize, m_pStream->GetDict(), m_pData,
+                             m_dwSize, m_ImageDecoder, m_pImageParam,
+                             estimated_size, bImageAcc)) {
     m_pData = pSrcData;
     m_dwSize = dwSrcSize;
-  } else {
-    bool bRet = PDF_DataDecode(pSrcData, dwSrcSize, m_pStream->GetDict(),
-                               m_pData, m_dwSize, m_ImageDecoder, m_pImageParam,
-                               estimated_size, bImageAcc);
-    if (!bRet) {
-      m_pData = pSrcData;
-      m_dwSize = dwSrcSize;
-    }
   }
   if (pSrcData != pStream->GetRawData() && pSrcData != m_pData)
     FX_Free(pSrcData);