XFA: Manual merge of Clean up IFX_BidiChar

- Replace IFX_BidiChar with just CFX_BidiChar
- Document implementation
- Change out parameters to pointers
- Remove dead code
- Add an enum for bidi directions
- Move several externs to a header
- Add unit tests

Original CL: https://codereview.chromium.org/1197643002

This version does not remove fx_arb.h and fx_arabic.h, as there is code
on the XFA branch that still uses parts of it.

R=tsepez@chromium.org

Review URL: https://codereview.chromium.org/1423103002 .

8 files changed, 459 insertions, 254 deletions

diff --git a/core/src/fpdftext/fpdf_text.cpp b/core/src/fpdftext/fpdf_text.cpp
index 2bd8b7d6ce..9ecbc21bda 100644
--- a/core/src/fpdftext/fpdf_text.cpp
+++ b/core/src/fpdftext/fpdf_text.cpp
@@ -9,7 +9,7 @@
 #include "../../include/fpdfapi/fpdf_pageobj.h"
 #include "../../include/fpdfapi/fpdf_resource.h"
 #include "../../include/fpdftext/fpdf_text.h"
-#include "../../include/fxcrt/fx_arb.h"
+#include "../../include/fxcrt/fx_bidi.h"
 #include "../../include/fxcrt/fx_ucd.h"
 #include "text_int.h"
 #include "txtproc.h"
@@ -315,35 +315,35 @@ void NormalizeString(CFX_WideString& str) {
     return;
   }
   CFX_WideString sBuffer;
-  nonstd::unique_ptr<IFX_BidiChar> pBidiChar(IFX_BidiChar::Create());
+  nonstd::unique_ptr<CFX_BidiChar> pBidiChar(new CFX_BidiChar);
   CFX_WordArray order;
   FX_BOOL bR2L = FALSE;
   int32_t start = 0, count = 0, i = 0;
   int nR2L = 0, nL2R = 0;
   for (i = 0; i < str.GetLength(); i++) {
     if (pBidiChar->AppendChar(str.GetAt(i))) {
-      int32_t ret = pBidiChar->GetBidiInfo(start, count);
+      CFX_BidiChar::Direction ret = pBidiChar->GetBidiInfo(&start, &count);
       order.Add(start);
       order.Add(count);
       order.Add(ret);
       if (!bR2L) {
-        if (ret == 2) {
+        if (ret == CFX_BidiChar::RIGHT) {
           nR2L++;
-        } else if (ret == 1) {
+        } else if (ret == CFX_BidiChar::LEFT) {
           nL2R++;
         }
       }
     }
   }
   if (pBidiChar->EndChar()) {
-    int32_t ret = pBidiChar->GetBidiInfo(start, count);
+    CFX_BidiChar::Direction ret = pBidiChar->GetBidiInfo(&start, &count);
     order.Add(start);
     order.Add(count);
     order.Add(ret);
     if (!bR2L) {
-      if (ret == 2) {
+      if (ret == CFX_BidiChar::RIGHT) {
         nR2L++;
-      } else if (ret == 1) {
+      } else if (ret == CFX_BidiChar::LEFT) {
         nL2R++;
       }
     }
diff --git a/core/src/fpdftext/fpdf_text_int.cpp b/core/src/fpdftext/fpdf_text_int.cpp
index aa25728c15..202fab45fa 100644
--- a/core/src/fpdftext/fpdf_text_int.cpp
+++ b/core/src/fpdftext/fpdf_text_int.cpp
@@ -13,7 +13,7 @@
 #include "../../include/fpdfapi/fpdf_pageobj.h"
 #include "../../include/fpdfapi/fpdf_resource.h"
 #include "../../include/fpdftext/fpdf_text.h"
-#include "../../include/fxcrt/fx_arb.h"
+#include "../../include/fxcrt/fx_bidi.h"
 #include "../../include/fxcrt/fx_ucd.h"
 #include "text_int.h"
 
@@ -1001,10 +1001,10 @@ int CPDF_TextPage::GetCharWidth(FX_DWORD charCode, CPDF_Font* pFont) const {
   }
   return w;
 }
-void CPDF_TextPage::OnPiece(IFX_BidiChar* pBidi, CFX_WideString& str) {
+void CPDF_TextPage::OnPiece(CFX_BidiChar* pBidi, CFX_WideString& str) {
   int32_t start, count;
-  int32_t ret = pBidi->GetBidiInfo(start, count);
-  if (ret == 2) {
+  CFX_BidiChar::Direction ret = pBidi->GetBidiInfo(&start, &count);
+  if (ret == CFX_BidiChar::RIGHT) {
     for (int i = start + count - 1; i >= start; i--) {
       m_TextBuf.AppendChar(str.GetAt(i));
       m_charList.Add(*(PAGECHAR_INFO*)m_TempCharList.GetAt(i));
@@ -1085,7 +1085,7 @@ void CPDF_TextPage::CloseTempLine() {
   if (count1 <= 0) {
     return;
   }
-  nonstd::unique_ptr<IFX_BidiChar> pBidiChar(IFX_BidiChar::Create());
+  nonstd::unique_ptr<CFX_BidiChar> pBidiChar(new CFX_BidiChar);
   CFX_WideString str = m_TempTextBuf.GetWideString();
   CFX_WordArray order;
   FX_BOOL bR2L = FALSE;
@@ -1107,28 +1107,28 @@ void CPDF_TextPage::CloseTempLine() {
       bPrevSpace = FALSE;
     }
     if (pBidiChar->AppendChar(str.GetAt(i))) {
-      int32_t ret = pBidiChar->GetBidiInfo(start, count);
+      CFX_BidiChar::Direction ret = pBidiChar->GetBidiInfo(&start, &count);
       order.Add(start);
       order.Add(count);
       order.Add(ret);
       if (!bR2L) {
-        if (ret == 2) {
+        if (ret == CFX_BidiChar::RIGHT) {
           nR2L++;
-        } else if (ret == 1) {
+        } else if (ret == CFX_BidiChar::LEFT) {
           nL2R++;
         }
       }
     }
   }
   if (pBidiChar->EndChar()) {
-    int32_t ret = pBidiChar->GetBidiInfo(start, count);
+    CFX_BidiChar::Direction ret = pBidiChar->GetBidiInfo(&start, &count);
     order.Add(start);
     order.Add(count);
     order.Add(ret);
     if (!bR2L) {
-      if (ret == 2) {
+      if (ret == CFX_BidiChar::RIGHT) {
         nR2L++;
-      } else if (ret == 1) {
+      } else if (ret == CFX_BidiChar::LEFT) {
         nL2R++;
       }
     }
@@ -1560,7 +1560,7 @@ void CPDF_TextPage::ProcessTextObject(PDFTEXT_Obj Obj) {
   FX_FLOAT baseSpace = _CalculateBaseSpace(pTextObj, matrix);
 
   FX_BOOL bIsBidiAndMirrosInverse = FALSE;
-  IFX_BidiChar* BidiChar = IFX_BidiChar::Create();
+  CFX_BidiChar* BidiChar = new CFX_BidiChar;
   int32_t nR2L = 0;
   int32_t nL2R = 0;
   int32_t start = 0, count = 0;
@@ -1579,19 +1579,19 @@ void CPDF_TextPage::ProcessTextObject(PDFTEXT_Obj Obj) {
       continue;
     }
     if (BidiChar && BidiChar->AppendChar(wChar)) {
-      int32_t ret = BidiChar->GetBidiInfo(start, count);
-      if (ret == 2) {
+      CFX_BidiChar::Direction ret = BidiChar->GetBidiInfo(&start, &count);
+      if (ret == CFX_BidiChar::RIGHT) {
         nR2L++;
-      } else if (ret == 1) {
+      } else if (ret == CFX_BidiChar::LEFT) {
         nL2R++;
       }
     }
   }
   if (BidiChar && BidiChar->EndChar()) {
-    int32_t ret = BidiChar->GetBidiInfo(start, count);
-    if (ret == 2) {
+    CFX_BidiChar::Direction ret = BidiChar->GetBidiInfo(&start, &count);
+    if (ret == CFX_BidiChar::RIGHT) {
       nR2L++;
-    } else if (ret == 1) {
+    } else if (ret == CFX_BidiChar::LEFT) {
       nL2R++;
     }
   }
diff --git a/core/src/fpdftext/text_int.h b/core/src/fpdftext/text_int.h
index b5a7734e54..d10c5501e6 100644
--- a/core/src/fpdftext/text_int.h
+++ b/core/src/fpdftext/text_int.h
@@ -119,7 +119,7 @@ class CPDF_TextPage : public IPDF_TextPage {
                            CPDF_TextObject* pTextObj2);
   int GetCharWidth(FX_DWORD charCode, CPDF_Font* pFont) const;
   void CloseTempLine();
-  void OnPiece(IFX_BidiChar* pBidi, CFX_WideString& str);
+  void OnPiece(CFX_BidiChar* pBidi, CFX_WideString& str);
   int32_t PreMarkedContent(PDFTEXT_Obj pObj);
   void ProcessMarkedContent(PDFTEXT_Obj pObj);
   void CheckMarkedContentObject(int32_t& start, int32_t& nCount) const;
diff --git a/core/src/fxcrt/fx_arabic.cpp b/core/src/fxcrt/fx_arabic.cpp
index 139e9f1f48..1869cb2008 100644
--- a/core/src/fxcrt/fx_arabic.cpp
+++ b/core/src/fxcrt/fx_arabic.cpp
@@ -7,112 +7,209 @@
 #include "../../include/fxcrt/fx_ucd.h"
 #include "fx_arabic.h"
 
-#ifdef __cplusplus
-extern "C" {
-#endif
-static const FX_ARBFORMTABLE g_FX_ArabicFormTables[] = {
-    {0xFE81, 0xFE82, 0xFE81, 0xFE82}, {0xFE83, 0xFE84, 0xFE83, 0xFE84},
-    {0xFE85, 0xFE86, 0xFE85, 0xFE86}, {0xFE87, 0xFE88, 0xFE87, 0xFE88},
-    {0xFE89, 0xFE8A, 0xFE8B, 0xFE8C}, {0xFE8D, 0xFE8E, 0xFE8D, 0xFE8E},
-    {0xFE8F, 0xFE90, 0xFE91, 0xFE92}, {0xFE93, 0xFE94, 0xFE93, 0xFE94},
-    {0xFE95, 0xFE96, 0xFE97, 0xFE98}, {0xFE99, 0xFE9A, 0xFE9B, 0xFE9C},
-    {0xFE9D, 0xFE9E, 0xFE9F, 0xFEA0}, {0xFEA1, 0xFEA2, 0xFEA3, 0xFEA4},
-    {0xFEA5, 0xFEA6, 0xFEA7, 0xFEA8}, {0xFEA9, 0xFEAA, 0xFEA9, 0xFEAA},
-    {0xFEAB, 0xFEAC, 0xFEAB, 0xFEAC}, {0xFEAD, 0xFEAE, 0xFEAD, 0xFEAE},
-    {0xFEAF, 0xFEB0, 0xFEAF, 0xFEB0}, {0xFEB1, 0xFEB2, 0xFEB3, 0xFEB4},
-    {0xFEB5, 0xFEB6, 0xFEB7, 0xFEB8}, {0xFEB9, 0xFEBA, 0xFEBB, 0xFEBC},
-    {0xFEBD, 0xFEBE, 0xFEBF, 0xFEC0}, {0xFEC1, 0xFEC2, 0xFEC3, 0xFEC4},
-    {0xFEC5, 0xFEC6, 0xFEC7, 0xFEC8}, {0xFEC9, 0xFECA, 0xFECB, 0xFECC},
-    {0xFECD, 0xFECE, 0xFECF, 0xFED0}, {0x063B, 0x063B, 0x063B, 0x063B},
-    {0x063C, 0x063C, 0x063C, 0x063C}, {0x063D, 0x063D, 0x063D, 0x063D},
-    {0x063E, 0x063E, 0x063E, 0x063E}, {0x063F, 0x063F, 0x063F, 0x063F},
-    {0x0640, 0x0640, 0x0640, 0x0640}, {0xFED1, 0xFED2, 0xFED3, 0xFED4},
-    {0xFED5, 0xFED6, 0xFED7, 0xFED8}, {0xFED9, 0xFEDA, 0xFEDB, 0xFEDC},
-    {0xFEDD, 0xFEDE, 0xFEDF, 0xFEE0}, {0xFEE1, 0xFEE2, 0xFEE3, 0xFEE4},
-    {0xFEE5, 0xFEE6, 0xFEE7, 0xFEE8}, {0xFEE9, 0xFEEA, 0xFEEB, 0xFEEC},
-    {0xFEED, 0xFEEE, 0xFEED, 0xFEEE}, {0xFEEF, 0xFEF0, 0xFBFE, 0xFBFF},
-    {0xFEF1, 0xFEF2, 0xFEF3, 0xFEF4}, {0x064B, 0x064B, 0x064B, 0x064B},
-    {0x064C, 0x064C, 0x064C, 0x064C}, {0x064D, 0x064D, 0x064D, 0x064D},
-    {0x064E, 0x064E, 0x064E, 0x064E}, {0x064F, 0x064F, 0x064F, 0x064F},
-    {0x0650, 0x0650, 0x0650, 0x0650}, {0x0651, 0x0651, 0x0651, 0x0651},
-    {0x0652, 0x0652, 0x0652, 0x0652}, {0x0653, 0x0653, 0x0653, 0x0653},
-    {0x0654, 0x0654, 0x0654, 0x0654}, {0x0655, 0x0655, 0x0655, 0x0655},
-    {0x0656, 0x0656, 0x0656, 0x0656}, {0x0657, 0x0657, 0x0657, 0x0657},
-    {0x0658, 0x0658, 0x0658, 0x0658}, {0x0659, 0x0659, 0x0659, 0x0659},
-    {0x065A, 0x065A, 0x065A, 0x065A}, {0x065B, 0x065B, 0x065B, 0x065B},
-    {0x065C, 0x065C, 0x065C, 0x065C}, {0x065D, 0x065D, 0x065D, 0x065D},
-    {0x065E, 0x065E, 0x065E, 0x065E}, {0x065F, 0x065F, 0x065F, 0x065F},
-    {0x0660, 0x0660, 0x0660, 0x0660}, {0x0661, 0x0661, 0x0661, 0x0661},
-    {0x0662, 0x0662, 0x0662, 0x0662}, {0x0663, 0x0663, 0x0663, 0x0663},
-    {0x0664, 0x0664, 0x0664, 0x0664}, {0x0665, 0x0665, 0x0665, 0x0665},
-    {0x0666, 0x0666, 0x0666, 0x0666}, {0x0667, 0x0667, 0x0667, 0x0667},
-    {0x0668, 0x0668, 0x0668, 0x0668}, {0x0669, 0x0669, 0x0669, 0x0669},
-    {0x066A, 0x066A, 0x066A, 0x066A}, {0x066B, 0x066B, 0x066B, 0x066B},
-    {0x066C, 0x066C, 0x066C, 0x066C}, {0x066D, 0x066D, 0x066D, 0x066D},
-    {0x066E, 0x066E, 0x066E, 0x066E}, {0x066F, 0x066F, 0x066F, 0x066F},
-    {0x0670, 0x0670, 0x0670, 0x0670}, {0xFB50, 0xFB51, 0xFB50, 0xFB51},
-    {0x0672, 0x0672, 0x0672, 0x0672}, {0x0673, 0x0673, 0x0673, 0x0673},
-    {0x0674, 0x0674, 0x0674, 0x0674}, {0x0675, 0x0675, 0x0675, 0x0675},
-    {0x0676, 0x0676, 0x0676, 0x0676}, {0x0677, 0x0677, 0x0677, 0x0677},
-    {0x0678, 0x0678, 0x0678, 0x0678}, {0xFB66, 0xFB67, 0xFB68, 0xFB69},
-    {0xFB5E, 0xFB5F, 0xFB60, 0xFB61}, {0xFB52, 0xFB53, 0xFB54, 0xFB55},
-    {0x067C, 0x067C, 0x067C, 0x067C}, {0x067D, 0x067D, 0x067D, 0x067D},
-    {0xFB56, 0xFB57, 0xFB58, 0xFB59}, {0xFB62, 0xFB63, 0xFB64, 0xFB65},
-    {0xFB5A, 0xFB5B, 0xFB5C, 0xFB5D}, {0x0681, 0x0681, 0x0681, 0x0681},
-    {0x0682, 0x0682, 0x0682, 0x0682}, {0xFB76, 0xFB77, 0xFB78, 0xFB79},
-    {0xFB72, 0xFB73, 0xFB74, 0xFB75}, {0x0685, 0x0685, 0x0685, 0x0685},
-    {0xFB7A, 0xFB7B, 0xFB7C, 0xFB7D}, {0xFB7E, 0xFB7F, 0xFB80, 0xFB81},
-    {0xFB88, 0xFB89, 0xFB88, 0xFB89}, {0x0689, 0x0689, 0x0689, 0x0689},
-    {0x068A, 0x068A, 0x068A, 0x068A}, {0x068B, 0x068B, 0x068B, 0x068B},
-    {0xFB84, 0xFB85, 0xFB84, 0xFB85}, {0xFB82, 0xFB83, 0xFB82, 0xFB83},
-    {0xFB86, 0xFB87, 0xFB86, 0xFB87}, {0x068F, 0x068F, 0x068F, 0x068F},
-    {0x0690, 0x0690, 0x0690, 0x0690}, {0xFB8C, 0xFB8D, 0xFB8C, 0xFB8D},
-    {0x0692, 0x0692, 0x0692, 0x0692}, {0x0693, 0x0693, 0x0693, 0x0693},
-    {0x0694, 0x0694, 0x0694, 0x0694}, {0x0695, 0x0695, 0x0695, 0x0695},
-    {0x0696, 0x0696, 0x0696, 0x0696}, {0x0697, 0x0697, 0x0697, 0x0697},
-    {0xFB8A, 0xFB8B, 0xFB8A, 0xFB8B}, {0x0699, 0x0699, 0x0699, 0x0699},
-    {0x069A, 0x069A, 0x069A, 0x069A}, {0x069B, 0x069B, 0x069B, 0x069B},
-    {0x069C, 0x069C, 0x069C, 0x069C}, {0x069D, 0x069D, 0x069D, 0x069D},
-    {0x069E, 0x069E, 0x069E, 0x069E}, {0x069F, 0x069F, 0x069F, 0x069F},
-    {0x06A0, 0x06A0, 0x06A0, 0x06A0}, {0x06A1, 0x06A1, 0x06A1, 0x06A1},
-    {0x06A2, 0x06A2, 0x06A2, 0x06A2}, {0x06A3, 0x06A3, 0x06A3, 0x06A3},
-    {0xFB6A, 0xFB6B, 0xFB6C, 0xFB6D}, {0x06A5, 0x06A5, 0x06A5, 0x06A5},
-    {0xFB6E, 0xFB6F, 0xFB70, 0xFB71}, {0x06A7, 0x06A7, 0x06A7, 0x06A7},
-    {0x06A8, 0x06A8, 0x06A8, 0x06A8}, {0xFB8E, 0xFB8F, 0xFB90, 0xFB91},
-    {0x06AA, 0x06AA, 0x06AA, 0x06AA}, {0x06AB, 0x06AB, 0x06AB, 0x06AB},
-    {0x06AC, 0x06AC, 0x06AC, 0x06AC}, {0xFBD3, 0xFBD4, 0xFBD5, 0xFBD6},
-    {0x06AE, 0x06AE, 0x06AE, 0x06AE}, {0xFB92, 0xFB93, 0xFB94, 0xFB95},
-    {0x06B0, 0x06B0, 0x06B0, 0x06B0}, {0xFB9A, 0xFB9B, 0xFB9C, 0xFB9D},
-    {0x06B2, 0x06B2, 0x06B2, 0x06B2}, {0xFB96, 0xFB97, 0xFB98, 0xFB99},
-    {0x06B4, 0x06B4, 0x06B4, 0x06B4}, {0x06B5, 0x06B5, 0x06B5, 0x06B5},
-    {0x06B6, 0x06B6, 0x06B6, 0x06B6}, {0x06B7, 0x06B7, 0x06B7, 0x06B7},
-    {0x06B8, 0x06B8, 0x06B8, 0x06B8}, {0x06B9, 0x06B9, 0x06B9, 0x06B9},
-    {0xFB9E, 0xFB9F, 0xFBE8, 0xFBE9}, {0xFBA0, 0xFBA1, 0xFBA2, 0xFBA3},
-    {0x06BC, 0x06BC, 0x06BC, 0x06BC}, {0x06BD, 0x06BD, 0x06BD, 0x06BD},
-    {0xFBAA, 0xFBAB, 0xFBAC, 0xFBAD}, {0x06BF, 0x06BF, 0x06BF, 0x06BF},
-    {0xFBA4, 0xFBA5, 0xFBA4, 0xFBA5}, {0xFBA6, 0xFBA7, 0xFBA8, 0xFBA9},
-    {0x06C2, 0x06C2, 0x06C2, 0x06C2}, {0x06C3, 0x06C3, 0x06C3, 0x06C3},
-    {0x06C4, 0x06C4, 0x06C4, 0x06C4}, {0xFBE0, 0xFBE1, 0xFBE0, 0xFBE1},
-    {0xFBD9, 0xFBDA, 0xFBD9, 0xFBDA}, {0xFBD7, 0xFBD8, 0xFBD7, 0xFBD8},
-    {0xFBDB, 0xFBDC, 0xFBDB, 0xFBDC}, {0xFBE2, 0xFBE3, 0xFBE2, 0xFBE3},
-    {0x06CA, 0x06CA, 0x06CA, 0x06CA}, {0xFBDE, 0xFBDF, 0xFBDE, 0xFBDF},
-    {0xFBFC, 0xFBFD, 0xFBFE, 0xFBFF}, {0x06CD, 0x06CD, 0x06CD, 0x06CD},
-    {0x06CE, 0x06CE, 0x06CE, 0x06CE}, {0x06CF, 0x06CF, 0x06CF, 0x06CF},
-    {0xFBE4, 0xFBE5, 0xFBE6, 0xFBE7}, {0x06D1, 0x06D1, 0x06D1, 0x06D1},
-    {0xFBAE, 0xFBAF, 0xFBAE, 0xFBAF}, {0xFBB0, 0xFBB1, 0xFBB0, 0xFBB1},
-    {0x06D4, 0x06D4, 0x06D4, 0x06D4}, {0x06D5, 0x06D5, 0x06D5, 0x06D5},
+namespace {
+
+const FX_ARBFORMTABLE g_FX_ArabicFormTables[] = {
+    {0xFE81, 0xFE82, 0xFE81, 0xFE82},
+    {0xFE83, 0xFE84, 0xFE83, 0xFE84},
+    {0xFE85, 0xFE86, 0xFE85, 0xFE86},
+    {0xFE87, 0xFE88, 0xFE87, 0xFE88},
+    {0xFE89, 0xFE8A, 0xFE8B, 0xFE8C},
+    {0xFE8D, 0xFE8E, 0xFE8D, 0xFE8E},
+    {0xFE8F, 0xFE90, 0xFE91, 0xFE92},
+    {0xFE93, 0xFE94, 0xFE93, 0xFE94},
+    {0xFE95, 0xFE96, 0xFE97, 0xFE98},
+    {0xFE99, 0xFE9A, 0xFE9B, 0xFE9C},
+    {0xFE9D, 0xFE9E, 0xFE9F, 0xFEA0},
+    {0xFEA1, 0xFEA2, 0xFEA3, 0xFEA4},
+    {0xFEA5, 0xFEA6, 0xFEA7, 0xFEA8},
+    {0xFEA9, 0xFEAA, 0xFEA9, 0xFEAA},
+    {0xFEAB, 0xFEAC, 0xFEAB, 0xFEAC},
+    {0xFEAD, 0xFEAE, 0xFEAD, 0xFEAE},
+    {0xFEAF, 0xFEB0, 0xFEAF, 0xFEB0},
+    {0xFEB1, 0xFEB2, 0xFEB3, 0xFEB4},
+    {0xFEB5, 0xFEB6, 0xFEB7, 0xFEB8},
+    {0xFEB9, 0xFEBA, 0xFEBB, 0xFEBC},
+    {0xFEBD, 0xFEBE, 0xFEBF, 0xFEC0},
+    {0xFEC1, 0xFEC2, 0xFEC3, 0xFEC4},
+    {0xFEC5, 0xFEC6, 0xFEC7, 0xFEC8},
+    {0xFEC9, 0xFECA, 0xFECB, 0xFECC},
+    {0xFECD, 0xFECE, 0xFECF, 0xFED0},
+    {0x063B, 0x063B, 0x063B, 0x063B},
+    {0x063C, 0x063C, 0x063C, 0x063C},
+    {0x063D, 0x063D, 0x063D, 0x063D},
+    {0x063E, 0x063E, 0x063E, 0x063E},
+    {0x063F, 0x063F, 0x063F, 0x063F},
+    {0x0640, 0x0640, 0x0640, 0x0640},
+    {0xFED1, 0xFED2, 0xFED3, 0xFED4},
+    {0xFED5, 0xFED6, 0xFED7, 0xFED8},
+    {0xFED9, 0xFEDA, 0xFEDB, 0xFEDC},
+    {0xFEDD, 0xFEDE, 0xFEDF, 0xFEE0},
+    {0xFEE1, 0xFEE2, 0xFEE3, 0xFEE4},
+    {0xFEE5, 0xFEE6, 0xFEE7, 0xFEE8},
+    {0xFEE9, 0xFEEA, 0xFEEB, 0xFEEC},
+    {0xFEED, 0xFEEE, 0xFEED, 0xFEEE},
+    {0xFEEF, 0xFEF0, 0xFBFE, 0xFBFF},
+    {0xFEF1, 0xFEF2, 0xFEF3, 0xFEF4},
+    {0x064B, 0x064B, 0x064B, 0x064B},
+    {0x064C, 0x064C, 0x064C, 0x064C},
+    {0x064D, 0x064D, 0x064D, 0x064D},
+    {0x064E, 0x064E, 0x064E, 0x064E},
+    {0x064F, 0x064F, 0x064F, 0x064F},
+    {0x0650, 0x0650, 0x0650, 0x0650},
+    {0x0651, 0x0651, 0x0651, 0x0651},
+    {0x0652, 0x0652, 0x0652, 0x0652},
+    {0x0653, 0x0653, 0x0653, 0x0653},
+    {0x0654, 0x0654, 0x0654, 0x0654},
+    {0x0655, 0x0655, 0x0655, 0x0655},
+    {0x0656, 0x0656, 0x0656, 0x0656},
+    {0x0657, 0x0657, 0x0657, 0x0657},
+    {0x0658, 0x0658, 0x0658, 0x0658},
+    {0x0659, 0x0659, 0x0659, 0x0659},
+    {0x065A, 0x065A, 0x065A, 0x065A},
+    {0x065B, 0x065B, 0x065B, 0x065B},
+    {0x065C, 0x065C, 0x065C, 0x065C},
+    {0x065D, 0x065D, 0x065D, 0x065D},
+    {0x065E, 0x065E, 0x065E, 0x065E},
+    {0x065F, 0x065F, 0x065F, 0x065F},
+    {0x0660, 0x0660, 0x0660, 0x0660},
+    {0x0661, 0x0661, 0x0661, 0x0661},
+    {0x0662, 0x0662, 0x0662, 0x0662},
+    {0x0663, 0x0663, 0x0663, 0x0663},
+    {0x0664, 0x0664, 0x0664, 0x0664},
+    {0x0665, 0x0665, 0x0665, 0x0665},
+    {0x0666, 0x0666, 0x0666, 0x0666},
+    {0x0667, 0x0667, 0x0667, 0x0667},
+    {0x0668, 0x0668, 0x0668, 0x0668},
+    {0x0669, 0x0669, 0x0669, 0x0669},
+    {0x066A, 0x066A, 0x066A, 0x066A},
+    {0x066B, 0x066B, 0x066B, 0x066B},
+    {0x066C, 0x066C, 0x066C, 0x066C},
+    {0x066D, 0x066D, 0x066D, 0x066D},
+    {0x066E, 0x066E, 0x066E, 0x066E},
+    {0x066F, 0x066F, 0x066F, 0x066F},
+    {0x0670, 0x0670, 0x0670, 0x0670},
+    {0xFB50, 0xFB51, 0xFB50, 0xFB51},
+    {0x0672, 0x0672, 0x0672, 0x0672},
+    {0x0673, 0x0673, 0x0673, 0x0673},
+    {0x0674, 0x0674, 0x0674, 0x0674},
+    {0x0675, 0x0675, 0x0675, 0x0675},
+    {0x0676, 0x0676, 0x0676, 0x0676},
+    {0x0677, 0x0677, 0x0677, 0x0677},
+    {0x0678, 0x0678, 0x0678, 0x0678},
+    {0xFB66, 0xFB67, 0xFB68, 0xFB69},
+    {0xFB5E, 0xFB5F, 0xFB60, 0xFB61},
+    {0xFB52, 0xFB53, 0xFB54, 0xFB55},
+    {0x067C, 0x067C, 0x067C, 0x067C},
+    {0x067D, 0x067D, 0x067D, 0x067D},
+    {0xFB56, 0xFB57, 0xFB58, 0xFB59},
+    {0xFB62, 0xFB63, 0xFB64, 0xFB65},
+    {0xFB5A, 0xFB5B, 0xFB5C, 0xFB5D},
+    {0x0681, 0x0681, 0x0681, 0x0681},
+    {0x0682, 0x0682, 0x0682, 0x0682},
+    {0xFB76, 0xFB77, 0xFB78, 0xFB79},
+    {0xFB72, 0xFB73, 0xFB74, 0xFB75},
+    {0x0685, 0x0685, 0x0685, 0x0685},
+    {0xFB7A, 0xFB7B, 0xFB7C, 0xFB7D},
+    {0xFB7E, 0xFB7F, 0xFB80, 0xFB81},
+    {0xFB88, 0xFB89, 0xFB88, 0xFB89},
+    {0x0689, 0x0689, 0x0689, 0x0689},
+    {0x068A, 0x068A, 0x068A, 0x068A},
+    {0x068B, 0x068B, 0x068B, 0x068B},
+    {0xFB84, 0xFB85, 0xFB84, 0xFB85},
+    {0xFB82, 0xFB83, 0xFB82, 0xFB83},
+    {0xFB86, 0xFB87, 0xFB86, 0xFB87},
+    {0x068F, 0x068F, 0x068F, 0x068F},
+    {0x0690, 0x0690, 0x0690, 0x0690},
+    {0xFB8C, 0xFB8D, 0xFB8C, 0xFB8D},
+    {0x0692, 0x0692, 0x0692, 0x0692},
+    {0x0693, 0x0693, 0x0693, 0x0693},
+    {0x0694, 0x0694, 0x0694, 0x0694},
+    {0x0695, 0x0695, 0x0695, 0x0695},
+    {0x0696, 0x0696, 0x0696, 0x0696},
+    {0x0697, 0x0697, 0x0697, 0x0697},
+    {0xFB8A, 0xFB8B, 0xFB8A, 0xFB8B},
+    {0x0699, 0x0699, 0x0699, 0x0699},
+    {0x069A, 0x069A, 0x069A, 0x069A},
+    {0x069B, 0x069B, 0x069B, 0x069B},
+    {0x069C, 0x069C, 0x069C, 0x069C},
+    {0x069D, 0x069D, 0x069D, 0x069D},
+    {0x069E, 0x069E, 0x069E, 0x069E},
+    {0x069F, 0x069F, 0x069F, 0x069F},
+    {0x06A0, 0x06A0, 0x06A0, 0x06A0},
+    {0x06A1, 0x06A1, 0x06A1, 0x06A1},
+    {0x06A2, 0x06A2, 0x06A2, 0x06A2},
+    {0x06A3, 0x06A3, 0x06A3, 0x06A3},
+    {0xFB6A, 0xFB6B, 0xFB6C, 0xFB6D},
+    {0x06A5, 0x06A5, 0x06A5, 0x06A5},
+    {0xFB6E, 0xFB6F, 0xFB70, 0xFB71},
+    {0x06A7, 0x06A7, 0x06A7, 0x06A7},
+    {0x06A8, 0x06A8, 0x06A8, 0x06A8},
+    {0xFB8E, 0xFB8F, 0xFB90, 0xFB91},
+    {0x06AA, 0x06AA, 0x06AA, 0x06AA},
+    {0x06AB, 0x06AB, 0x06AB, 0x06AB},
+    {0x06AC, 0x06AC, 0x06AC, 0x06AC},
+    {0xFBD3, 0xFBD4, 0xFBD5, 0xFBD6},
+    {0x06AE, 0x06AE, 0x06AE, 0x06AE},
+    {0xFB92, 0xFB93, 0xFB94, 0xFB95},
+    {0x06B0, 0x06B0, 0x06B0, 0x06B0},
+    {0xFB9A, 0xFB9B, 0xFB9C, 0xFB9D},
+    {0x06B2, 0x06B2, 0x06B2, 0x06B2},
+    {0xFB96, 0xFB97, 0xFB98, 0xFB99},
+    {0x06B4, 0x06B4, 0x06B4, 0x06B4},
+    {0x06B5, 0x06B5, 0x06B5, 0x06B5},
+    {0x06B6, 0x06B6, 0x06B6, 0x06B6},
+    {0x06B7, 0x06B7, 0x06B7, 0x06B7},
+    {0x06B8, 0x06B8, 0x06B8, 0x06B8},
+    {0x06B9, 0x06B9, 0x06B9, 0x06B9},
+    {0xFB9E, 0xFB9F, 0xFBE8, 0xFBE9},
+    {0xFBA0, 0xFBA1, 0xFBA2, 0xFBA3},
+    {0x06BC, 0x06BC, 0x06BC, 0x06BC},
+    {0x06BD, 0x06BD, 0x06BD, 0x06BD},
+    {0xFBAA, 0xFBAB, 0xFBAC, 0xFBAD},
+    {0x06BF, 0x06BF, 0x06BF, 0x06BF},
+    {0xFBA4, 0xFBA5, 0xFBA4, 0xFBA5},
+    {0xFBA6, 0xFBA7, 0xFBA8, 0xFBA9},
+    {0x06C2, 0x06C2, 0x06C2, 0x06C2},
+    {0x06C3, 0x06C3, 0x06C3, 0x06C3},
+    {0x06C4, 0x06C4, 0x06C4, 0x06C4},
+    {0xFBE0, 0xFBE1, 0xFBE0, 0xFBE1},
+    {0xFBD9, 0xFBDA, 0xFBD9, 0xFBDA},
+    {0xFBD7, 0xFBD8, 0xFBD7, 0xFBD8},
+    {0xFBDB, 0xFBDC, 0xFBDB, 0xFBDC},
+    {0xFBE2, 0xFBE3, 0xFBE2, 0xFBE3},
+    {0x06CA, 0x06CA, 0x06CA, 0x06CA},
+    {0xFBDE, 0xFBDF, 0xFBDE, 0xFBDF},
+    {0xFBFC, 0xFBFD, 0xFBFE, 0xFBFF},
+    {0x06CD, 0x06CD, 0x06CD, 0x06CD},
+    {0x06CE, 0x06CE, 0x06CE, 0x06CE},
+    {0x06CF, 0x06CF, 0x06CF, 0x06CF},
+    {0xFBE4, 0xFBE5, 0xFBE6, 0xFBE7},
+    {0x06D1, 0x06D1, 0x06D1, 0x06D1},
+    {0xFBAE, 0xFBAF, 0xFBAE, 0xFBAF},
+    {0xFBB0, 0xFBB1, 0xFBB0, 0xFBB1},
+    {0x06D4, 0x06D4, 0x06D4, 0x06D4},
+    {0x06D5, 0x06D5, 0x06D5, 0x06D5},
 };
-static const FX_ARAALEF gs_FX_AlefTable[] = {
+
+const FX_ARAALEF gs_FX_AlefTable[] = {
     {0x0622, 0xFEF5},
     {0x0623, 0xFEF7},
     {0x0625, 0xFEF9},
     {0x0627, 0xFEFB},
 };
-static const FX_ARASHADDA gs_FX_ShaddaTable[] = {
-    {0x064C, 0xFC5E}, {0x064D, 0xFC5F}, {0x064E, 0xFC60},
-    {0x064F, 0xFC61}, {0x0650, 0xFC62},
+
+const FX_ARASHADDA gs_FX_ShaddaTable[] = {
+    {0x064C, 0xFC5E},
+    {0x064D, 0xFC5F},
+    {0x064E, 0xFC60},
+    {0x064F, 0xFC61},
+    {0x0650, 0xFC62},
 };
-FX_LPCARBFORMTABLE FX_GetArabicFormTable(FX_WCHAR unicode) {
+
+}  // namespace
+
+const FX_ARBFORMTABLE* FX_GetArabicFormTable(FX_WCHAR unicode) {
   if (unicode < 0x622 || unicode > 0x6d5) {
     return NULL;
   }
@@ -140,9 +237,7 @@ FX_WCHAR FX_GetArabicFromShaddaTable(FX_WCHAR shadda) {
   }
   return shadda;
 }
-#ifdef __cplusplus
-};
-#endif
+
 IFX_ArabicChar* IFX_ArabicChar::Create() {
   return new CFX_ArabicChar;
 }
@@ -168,7 +263,7 @@ FX_WCHAR CFX_ArabicChar::GetFormChar(const CFX_Char* cur,
                                      const CFX_Char* next) const {
   FX_CHARTYPE eCur;
   FX_WCHAR wCur;
-  FX_LPCARBFORMTABLE ft = ParseChar(cur, wCur, eCur);
+  const FX_ARBFORMTABLE* ft = ParseChar(cur, wCur, eCur);
   if (eCur < FX_CHARTYPE_ArabicAlef || eCur >= FX_CHARTYPE_ArabicNormal) {
     return wCur;
   }
@@ -200,9 +295,9 @@ FX_WCHAR CFX_ArabicChar::GetFormChar(const CFX_Char* cur,
     }
   }
 }
-FX_LPCARBFORMTABLE CFX_ArabicChar::ParseChar(const CFX_Char* pTC,
-                                             FX_WCHAR& wChar,
-                                             FX_CHARTYPE& eType) const {
+const FX_ARBFORMTABLE* CFX_ArabicChar::ParseChar(const CFX_Char* pTC,
+                                                 FX_WCHAR& wChar,
+                                                 FX_CHARTYPE& eType) const {
   if (pTC == NULL) {
     eType = FX_CHARTYPE_Unknown;
     wChar = 0xFEFF;
@@ -210,7 +305,7 @@ FX_LPCARBFORMTABLE CFX_ArabicChar::ParseChar(const CFX_Char* pTC,
   }
   eType = (FX_CHARTYPE)pTC->GetCharType();
   wChar = (FX_WCHAR)pTC->m_wCharCode;
-  FX_LPCARBFORMTABLE pFT = FX_GetArabicFormTable(wChar);
+  const FX_ARBFORMTABLE* pFT = FX_GetArabicFormTable(wChar);
   if (pFT == NULL || eType >= FX_CHARTYPE_ArabicNormal) {
     eType = FX_CHARTYPE_Unknown;
   }
@@ -1053,77 +1148,3 @@ void FX_BidiLine(CFX_RTFCharArray& chars, int32_t iCount, int32_t iBaseLevel) {
   CFX_BidiLineTemplate<CFX_RTFChar> blt;
   blt.FX_BidiLine(chars, iCount, iBaseLevel);
 }
-IFX_BidiChar* IFX_BidiChar::Create() {
-  return new CFX_BidiChar;
-}
-CFX_BidiChar::CFX_BidiChar()
-    : m_bSeparateNeutral(TRUE),
-      m_iCurStart(0),
-      m_iCurCount(0),
-      m_iCurBidi(0),
-      m_iLastBidi(0),
-      m_iLastStart(0),
-      m_iLastCount(0) {}
-void CFX_BidiChar::SetPolicy(FX_BOOL bSeparateNeutral) {
-  m_bSeparateNeutral = bSeparateNeutral;
-}
-
-FX_BOOL CFX_BidiChar::AppendChar(FX_WCHAR wch) {
-  FX_DWORD dwProps = kTextLayoutCodeProperties[(FX_WORD)wch];
-  int32_t iBidiCls = (dwProps & FX_BIDICLASSBITSMASK) >> FX_BIDICLASSBITS;
-  int32_t iContext = 0;
-  switch (iBidiCls) {
-    case FX_BIDICLASS_L:
-    case FX_BIDICLASS_AN:
-    case FX_BIDICLASS_EN:
-      iContext = 1;
-      break;
-    case FX_BIDICLASS_R:
-    case FX_BIDICLASS_AL:
-      iContext = 2;
-      break;
-  }
-  FX_BOOL bRet = FALSE;
-  if (iContext != m_iCurBidi) {
-    if (m_bSeparateNeutral) {
-      bRet = TRUE;
-    } else {
-      if (m_iCurBidi == 0) {
-        bRet = (m_iCurCount > 0);
-      } else {
-        bRet = (iContext != 0);
-      }
-    }
-    if (bRet) {
-      m_iLastBidi = m_iCurBidi;
-      m_iLastStart = m_iCurStart;
-      m_iCurStart = m_iCurCount;
-      m_iLastCount = m_iCurCount - m_iLastStart;
-    }
-    if (m_bSeparateNeutral || iContext != 0) {
-      m_iCurBidi = iContext;
-    }
-  }
-  m_iCurCount++;
-  return bRet;
-}
-FX_BOOL CFX_BidiChar::EndChar() {
-  m_iLastBidi = m_iCurBidi;
-  m_iLastStart = m_iCurStart;
-  m_iCurStart = m_iCurCount;
-  m_iLastCount = m_iCurCount - m_iLastStart;
-  return m_iLastCount > 0;
-}
-int32_t CFX_BidiChar::GetBidiInfo(int32_t& iStart, int32_t& iCount) {
-  iStart = m_iLastStart;
-  iCount = m_iLastCount;
-  return m_iLastBidi;
-}
-void CFX_BidiChar::Reset() {
-  m_iCurStart = 0;
-  m_iCurCount = 0;
-  m_iCurBidi = 0;
-  m_iLastBidi = 0;
-  m_iLastStart = 0;
-  m_iLastCount = 0;
-}
diff --git a/core/src/fxcrt/fx_arabic.h b/core/src/fxcrt/fx_arabic.h
index 83893e3774..8fde73d5d9 100644
--- a/core/src/fxcrt/fx_arabic.h
+++ b/core/src/fxcrt/fx_arabic.h
@@ -23,9 +23,9 @@ class CFX_ArabicChar : public IFX_ArabicChar {
                                const CFX_Char* next) const;
 
  protected:
-  FX_LPCARBFORMTABLE ParseChar(const CFX_Char* pTC,
-                               FX_WCHAR& wChar,
-                               FX_CHARTYPE& eType) const;
+  const FX_ARBFORMTABLE* ParseChar(const CFX_Char* pTC,
+                                   FX_WCHAR& wChar,
+                                   FX_CHARTYPE& eType) const;
 };
 void FX_BidiReverseString(CFX_WideString& wsText,
                           int32_t iStart,
@@ -207,25 +207,5 @@ int32_t FX_BidiReorderLevel(int32_t iBaseLevel,
 void FX_BidiReorder(int32_t iBaseLevel,
                     CFX_WideString& wsText,
                     const CFX_Int32Array& levels);
-class CFX_BidiChar final : public IFX_BidiChar {
- public:
-  CFX_BidiChar();
-  ~CFX_BidiChar() override {}
-
-  void SetPolicy(FX_BOOL bSeparateNeutral = TRUE) override;
-  FX_BOOL AppendChar(FX_WCHAR wch) override;
-  FX_BOOL EndChar() override;
-  int32_t GetBidiInfo(int32_t& iStart, int32_t& iCount) override;
-  void Reset() override;
-
- private:
-  FX_BOOL m_bSeparateNeutral;
-  int32_t m_iCurStart;
-  int32_t m_iCurCount;
-  int32_t m_iCurBidi;
-  int32_t m_iLastBidi;
-  int32_t m_iLastStart;
-  int32_t m_iLastCount;
-};
 
 #endif  // CORE_SRC_FXCRT_FX_ARABIC_H_
diff --git a/core/src/fxcrt/fx_bidi.cpp b/core/src/fxcrt/fx_bidi.cpp
new file mode 100644
index 0000000000..0310fa0e94
--- /dev/null
+++ b/core/src/fxcrt/fx_bidi.cpp
@@ -0,0 +1,66 @@
+// Copyright 2014 PDFium Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style license that can be
+// found in the LICENSE file.
+
+// Original code copyright 2014 Foxit Software Inc. http://www.foxitsoftware.com
+
+#include "../../include/fxcrt/fx_bidi.h"
+#include "../../include/fxcrt/fx_ucd.h"
+
+CFX_BidiChar::CFX_BidiChar()
+    : m_iCurStart(0),
+      m_iCurCount(0),
+      m_CurBidi(NEUTRAL),
+      m_iLastStart(0),
+      m_iLastCount(0),
+      m_LastBidi(NEUTRAL) {
+}
+
+CFX_BidiChar::~CFX_BidiChar() {
+}
+
+bool CFX_BidiChar::AppendChar(FX_WCHAR wch) {
+  FX_DWORD dwProps = FX_GetUnicodeProperties(wch);
+  int32_t iBidiCls = (dwProps & FX_BIDICLASSBITSMASK) >> FX_BIDICLASSBITS;
+  Direction bidi = NEUTRAL;
+  switch (iBidiCls) {
+    case FX_BIDICLASS_L:
+    case FX_BIDICLASS_AN:
+    case FX_BIDICLASS_EN:
+      bidi = LEFT;
+      break;
+    case FX_BIDICLASS_R:
+    case FX_BIDICLASS_AL:
+      bidi = RIGHT;
+      break;
+  }
+
+  bool bRet = (bidi != m_CurBidi);
+  if (bRet) {
+    SaveCurrentStateToLastState();
+    m_CurBidi = bidi;
+  }
+  m_iCurCount++;
+  return bRet;
+}
+
+bool CFX_BidiChar::EndChar() {
+  SaveCurrentStateToLastState();
+  return m_iLastCount > 0;
+}
+
+CFX_BidiChar::Direction CFX_BidiChar::GetBidiInfo(int32_t* iStart,
+                                                  int32_t* iCount) const {
+  if (iStart)
+    *iStart = m_iLastStart;
+  if (iCount)
+    *iCount = m_iLastCount;
+  return m_LastBidi;
+}
+
+void CFX_BidiChar::SaveCurrentStateToLastState() {
+  m_LastBidi = m_CurBidi;
+  m_iLastStart = m_iCurStart;
+  m_iCurStart = m_iCurCount;
+  m_iLastCount = m_iCurCount - m_iLastStart;
+}
diff --git a/core/src/fxcrt/fx_bidi_unittest.cpp b/core/src/fxcrt/fx_bidi_unittest.cpp
new file mode 100644
index 0000000000..c629cbbdc6
--- /dev/null
+++ b/core/src/fxcrt/fx_bidi_unittest.cpp
@@ -0,0 +1,136 @@
+// Copyright 2015 PDFium Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style license that can be
+// found in the LICENSE file.
+
+#include "testing/gtest/include/gtest/gtest.h"
+#include "../../include/fxcrt/fx_bidi.h"
+
+namespace {
+
+const FX_WCHAR kNeutralChar = 32;
+const FX_WCHAR kLeftChar = 65;
+const FX_WCHAR kRightChar = 1424;
+
+}  // namespace
+
+TEST(fxcrt, BidiCharEmpty) {
+  int32_t start = -1;
+  int32_t count = -1;
+  CFX_BidiChar bidi;
+  CFX_BidiChar::Direction dir = bidi.GetBidiInfo(nullptr, nullptr);
+  EXPECT_EQ(CFX_BidiChar::NEUTRAL, dir);
+
+  dir = bidi.GetBidiInfo(&start, nullptr);
+  EXPECT_EQ(CFX_BidiChar::NEUTRAL, dir);
+  EXPECT_EQ(0, start);
+
+  dir = bidi.GetBidiInfo(nullptr, &count);
+  EXPECT_EQ(CFX_BidiChar::NEUTRAL, dir);
+  EXPECT_EQ(0, count);
+
+  start = -1;
+  count = -1;
+  dir = bidi.GetBidiInfo(&start, &count);
+  EXPECT_EQ(CFX_BidiChar::NEUTRAL, dir);
+  EXPECT_EQ(0, start);
+  EXPECT_EQ(0, count);
+
+  EXPECT_FALSE(bidi.EndChar());
+}
+
+TEST(fxcrt, BidiCharLeft) {
+  int32_t start = -1;
+  int32_t count = -1;
+  CFX_BidiChar bidi;
+
+  EXPECT_TRUE(bidi.AppendChar(kLeftChar));
+  CFX_BidiChar::Direction dir = bidi.GetBidiInfo(&start, &count);
+  EXPECT_EQ(0, start);
+  EXPECT_EQ(0, count);
+
+  EXPECT_FALSE(bidi.AppendChar(kLeftChar));
+  EXPECT_FALSE(bidi.AppendChar(kLeftChar));
+
+  dir = bidi.GetBidiInfo(&start, &count);
+  EXPECT_EQ(CFX_BidiChar::NEUTRAL, dir);
+  EXPECT_EQ(0, start);
+  EXPECT_EQ(0, count);
+
+  EXPECT_TRUE(bidi.EndChar());
+  dir = bidi.GetBidiInfo(&start, &count);
+  EXPECT_EQ(CFX_BidiChar::LEFT, dir);
+  EXPECT_EQ(0, start);
+  EXPECT_EQ(3, count);
+
+  EXPECT_FALSE(bidi.EndChar());
+}
+
+TEST(fxcrt, BidiCharLeftNeutralRight) {
+  int32_t start = -1;
+  int32_t count = -1;
+  CFX_BidiChar bidi;
+
+  EXPECT_TRUE(bidi.AppendChar(kLeftChar));
+  CFX_BidiChar::Direction dir = bidi.GetBidiInfo(&start, &count);
+  EXPECT_EQ(0, start);
+  EXPECT_EQ(0, count);
+
+  EXPECT_FALSE(bidi.AppendChar(kLeftChar));
+  EXPECT_FALSE(bidi.AppendChar(kLeftChar));
+  EXPECT_TRUE(bidi.AppendChar(kNeutralChar));
+  dir = bidi.GetBidiInfo(&start, &count);
+  EXPECT_EQ(0, start);
+  EXPECT_EQ(3, count);
+
+  EXPECT_FALSE(bidi.AppendChar(kNeutralChar));
+  EXPECT_FALSE(bidi.AppendChar(kNeutralChar));
+  EXPECT_FALSE(bidi.AppendChar(kNeutralChar));
+  EXPECT_TRUE(bidi.AppendChar(kRightChar));
+  dir = bidi.GetBidiInfo(&start, &count);
+  EXPECT_EQ(CFX_BidiChar::NEUTRAL, dir);
+  EXPECT_EQ(3, start);
+  EXPECT_EQ(4, count);
+
+  EXPECT_TRUE(bidi.EndChar());
+  dir = bidi.GetBidiInfo(&start, &count);
+  EXPECT_EQ(CFX_BidiChar::RIGHT, dir);
+  EXPECT_EQ(7, start);
+  EXPECT_EQ(1, count);
+
+  EXPECT_FALSE(bidi.EndChar());
+}
+
+TEST(fxcrt, BidiCharLeftRightLeft) {
+  int32_t start = -1;
+  int32_t count = -1;
+  CFX_BidiChar bidi;
+
+  EXPECT_TRUE(bidi.AppendChar(kLeftChar));
+  CFX_BidiChar::Direction dir = bidi.GetBidiInfo(&start, &count);
+  EXPECT_EQ(0, start);
+  EXPECT_EQ(0, count);
+
+  EXPECT_FALSE(bidi.AppendChar(kLeftChar));
+  EXPECT_FALSE(bidi.AppendChar(kLeftChar));
+  EXPECT_TRUE(bidi.AppendChar(kRightChar));
+  dir = bidi.GetBidiInfo(&start, &count);
+  EXPECT_EQ(0, start);
+  EXPECT_EQ(3, count);
+
+  EXPECT_FALSE(bidi.AppendChar(kRightChar));
+  EXPECT_FALSE(bidi.AppendChar(kRightChar));
+  EXPECT_FALSE(bidi.AppendChar(kRightChar));
+  EXPECT_TRUE(bidi.AppendChar(kLeftChar));
+  dir = bidi.GetBidiInfo(&start, &count);
+  EXPECT_EQ(CFX_BidiChar::RIGHT, dir);
+  EXPECT_EQ(3, start);
+  EXPECT_EQ(4, count);
+
+  EXPECT_TRUE(bidi.EndChar());
+  dir = bidi.GetBidiInfo(&start, &count);
+  EXPECT_EQ(CFX_BidiChar::LEFT, dir);
+  EXPECT_EQ(7, start);
+  EXPECT_EQ(1, count);
+
+  EXPECT_FALSE(bidi.EndChar());
+}
diff --git a/core/src/fxcrt/fx_unicode.cpp b/core/src/fxcrt/fx_unicode.cpp
index 67ff009513..105301e0a8 100644
--- a/core/src/fxcrt/fx_unicode.cpp
+++ b/core/src/fxcrt/fx_unicode.cpp
@@ -7,54 +7,56 @@
 #include "../../include/fxcrt/fx_ucd.h"
 
 FX_DWORD FX_GetUnicodeProperties(FX_WCHAR wch) {
-  return kTextLayoutCodeProperties[(FX_WORD)wch];
+  size_t idx = static_cast<size_t>(wch);
+  if (idx < kTextLayoutCodePropertiesSize)
+    return kTextLayoutCodeProperties[(FX_WORD)wch];
+  return 0;
 }
+
 FX_BOOL FX_IsCtrlCode(FX_WCHAR ch) {
-  FX_DWORD dwRet =
-      (kTextLayoutCodeProperties[(FX_WORD)ch] & FX_CHARTYPEBITSMASK);
+  FX_DWORD dwRet = (FX_GetUnicodeProperties(ch) & FX_CHARTYPEBITSMASK);
   return dwRet == FX_CHARTYPE_Tab || dwRet == FX_CHARTYPE_Control;
 }
-FX_BOOL FX_IsRotationCode(FX_WCHAR ch) {
-  return (kTextLayoutCodeProperties[(FX_WORD)ch] & 0x8000) != 0;
-}
-FX_BOOL FX_IsCombinationChar(FX_WCHAR wch) {
-  FX_DWORD dwProps =
-      (kTextLayoutCodeProperties[(FX_WORD)wch] & FX_CHARTYPEBITSMASK);
-  return dwProps == FX_CHARTYPE_Combination;
-}
-FX_BOOL FX_IsBidiChar(FX_WCHAR wch) {
-  FX_DWORD dwProps = kTextLayoutCodeProperties[(FX_WORD)wch];
-  int32_t iBidiCls = (dwProps & FX_BIDICLASSBITSMASK) >> FX_BIDICLASSBITS;
-  return (FX_BIDICLASS_R == iBidiCls || FX_BIDICLASS_AL == iBidiCls);
-}
+
 FX_WCHAR FX_GetMirrorChar(FX_WCHAR wch, FX_BOOL bRTL, FX_BOOL bVertical) {
-  FX_DWORD dwProps = kTextLayoutCodeProperties[(FX_WORD)wch];
+  FX_DWORD dwProps = FX_GetUnicodeProperties(wch);
   FX_DWORD dwTemp = (dwProps & 0xFF800000);
   if (bRTL && dwTemp < 0xFF800000) {
-    wch = kFXTextLayoutBidiMirror[dwTemp >> 23];
-    dwProps = kTextLayoutCodeProperties[(FX_WORD)wch];
+    size_t idx = dwTemp >> 23;
+    if (idx < kFXTextLayoutBidiMirrorSize) {
+      wch = kFXTextLayoutBidiMirror[idx];
+      dwProps = FX_GetUnicodeProperties(wch);
+    }
   }
   if (bVertical) {
     dwTemp = (dwProps & 0x007E0000);
     if (dwTemp < 0x007E0000) {
-      wch = kFXTextLayoutVerticalMirror[dwTemp >> 17];
+      size_t idx = dwTemp >> 17;
+      if (idx < kFXTextLayoutVerticalMirrorSize)
+        wch = kFXTextLayoutVerticalMirror[idx];
     }
   }
   return wch;
 }
+
 FX_WCHAR FX_GetMirrorChar(FX_WCHAR wch,
                           FX_DWORD dwProps,
                           FX_BOOL bRTL,
                           FX_BOOL bVertical) {
   FX_DWORD dwTemp = (dwProps & 0xFF800000);
   if (bRTL && dwTemp < 0xFF800000) {
-    wch = kFXTextLayoutBidiMirror[dwTemp >> 23];
-    dwProps = kTextLayoutCodeProperties[(FX_WORD)wch];
+    size_t idx = dwTemp >> 23;
+    if (idx < kFXTextLayoutBidiMirrorSize) {
+      wch = kFXTextLayoutBidiMirror[idx];
+      dwProps = FX_GetUnicodeProperties(wch);
+    }
   }
   if (bVertical) {
     dwTemp = (dwProps & 0x007E0000);
     if (dwTemp < 0x007E0000) {
-      wch = kFXTextLayoutVerticalMirror[dwTemp >> 17];
+      size_t idx = dwTemp >> 17;
+      if (idx < kFXTextLayoutVerticalMirrorSize)
+        wch = kFXTextLayoutVerticalMirror[idx];
     }
   }
   return wch;