A fix for Issue 2768 "IME: Current clause of Japanese IME doesn't appear to reflect its rage change."

This issue is caused by my code that cannot extract a target clause from a composition string when there is an input clause after a target clause.
when a user changes the range of a target clause, Japanese IMEs creates a composite clause which consists of a new target clause and an input clause. My IME code treats such composite clause as a target clause and cannot reflect the change.
To fix this problem, this code changes the algorithm which extracts a target clause.
Review URL: http://codereview.chromium.org/8970

git-svn-id: svn://svn.chromium.org/chrome/trunk/src@4569 0039d316-1c4b-4281-b951-d872f2087c98

1 files changed, 15 insertions, 7 deletions

diff --git a/chrome/browser/ime_input.cc b/chrome/browser/ime_input.cc
index 1b81827..83bd090 100644
--- a/chrome/browser/ime_input.cc
+++ b/chrome/browser/ime_input.cc
@@ -196,15 +196,23 @@ void ImeInput::GetCaret(HIMC imm_context, LPARAM lparam,
         if (attribute_data.get()) {
           ::ImmGetCompositionString(imm_context, GCS_COMPATTR,
                                     attribute_data.get(), attribute_size);
-          int i = 0;
-          for (; i < attribute_size; i++) {
-            if (IsTargetAttribute(attribute_data[i])) break;
+          for (target_start = 0; target_start < attribute_size;
+               ++target_start) {
+            if (IsTargetAttribute(attribute_data[target_start]))
+              break;
           }
-          target_start = i;
-          for (; i < attribute_size; i++) {
-            if (!IsTargetAttribute(attribute_data[i])) break;
+          for (target_end = target_start; target_end < attribute_size;
+               ++target_end) {
+            if (!IsTargetAttribute(attribute_data[target_end]))
+              break;
+          }
+          if (target_start == attribute_size) {
+            // This composition clause does not contain any target clauses,
+            // i.e. this clauses is an input clause.
+            // We treat whole this clause as a target clause.
+            target_end = target_start;
+            target_start = 0;
           }
-          target_end = i;
         }
       }
     }