From 4047998c2a0c635c59f41347f0ec7a558726c179 Mon Sep 17 00:00:00 2001
From: Masayuki Nakano <masayuki@d-toybox.com>
Date: Mon, 17 Aug 2015 20:58:38 +0900
Subject: [PATCH] Bug 555642 part.2 IME handlers on Windows shouldn't append
 caret range if the caret is in the target clause which doesn't have specific
 style r=m_kato

---
 widget/windows/IMMHandler.cpp   | 16 ++++++++++++++--
 widget/windows/TSFTextStore.cpp | 22 ++++++++++++++++------
 2 files changed, 30 insertions(+), 8 deletions(-)

diff --git a/widget/windows/IMMHandler.cpp b/widget/windows/IMMHandler.cpp
index 2be682693e99..67a359e7c02f 100644
--- a/widget/windows/IMMHandler.cpp
+++ b/widget/windows/IMMHandler.cpp
@@ -1971,8 +1971,8 @@ IMMHandler::CreateTextRangeArray()
     return textRangeArray.forget();
   }
 
-  int32_t cursor = mCursorPosition;
-  if (uint32_t(cursor) > mCompositionString.Length()) {
+  uint32_t cursor = static_cast<uint32_t>(mCursorPosition);
+  if (cursor > mCompositionString.Length()) {
     MOZ_LOG(gIMMLog, LogLevel::Info,
       ("IMM: CreateTextRangeArray, mCursorPosition=%ld. "
        "This is larger than mCompositionString.Length()=%lu",
@@ -1980,6 +1980,18 @@ IMMHandler::CreateTextRangeArray()
     cursor = mCompositionString.Length();
   }
 
+  // If caret is in the target clause, the target clause will be painted as
+  // normal selection range.  Since caret shouldn't be in selection range on
+  // Windows, we shouldn't append caret range in such case.
+  const TextRange* targetClause = textRangeArray->GetTargetClause();
+  if (targetClause &&
+      cursor >= targetClause->mStartOffset &&
+      cursor <= targetClause->mEndOffset) {
+    MOZ_LOG(gIMMLog, LogLevel::Info,
+      ("IMM: CreateTextRangeArray, no caret due to it's in the target clause"));
+    return textRangeArray.forget();
+  }
+
   range.mStartOffset = range.mEndOffset = cursor;
   range.mRangeType = NS_TEXTRANGE_CARETPOSITION;
   textRangeArray->AppendElement(range);
diff --git a/widget/windows/TSFTextStore.cpp b/widget/windows/TSFTextStore.cpp
index c70f9ab39e86..16c003b994fe 100644
--- a/widget/windows/TSFTextStore.cpp
+++ b/widget/windows/TSFTextStore.cpp
@@ -2581,12 +2581,22 @@ TSFTextStore::RecordCompositionUpdateAction()
   }
 
   // The caret position has to be collapsed.
-  LONG caretPosition = currentSel.MaxOffset();
-  caretPosition -= mComposition.mStart;
-  TextRange caretRange;
-  caretRange.mStartOffset = caretRange.mEndOffset = uint32_t(caretPosition);
-  caretRange.mRangeType = NS_TEXTRANGE_CARETPOSITION;
-  action->mRanges->AppendElement(caretRange);
+  uint32_t caretPosition =
+    static_cast<uint32_t>(currentSel.MaxOffset() - mComposition.mStart);
+
+  // If caret is in the target clause and it doesn't have specific style,
+  // the target clause will be painted as normal selection range.  Since caret
+  // shouldn't be in selection range on Windows, we shouldn't append caret
+  // range in such case.
+  const TextRange* targetClause = action->mRanges->GetTargetClause();
+  if (!targetClause || targetClause->mRangeStyle.IsDefined() ||
+      caretPosition < targetClause->mStartOffset ||
+      caretPosition > targetClause->mEndOffset) {
+    TextRange caretRange;
+    caretRange.mStartOffset = caretRange.mEndOffset = caretPosition;
+    caretRange.mRangeType = NS_TEXTRANGE_CARETPOSITION;
+    action->mRanges->AppendElement(caretRange);
+  }
 
   action->mIncomplete = false;