Fixes Issue 7377: Regression: Omnibox trims URL ending with 0x85

To fix this issue, this change adds a new function TrimWhitespaceUTF8(), which trims space characters (including non-printable characters and broken UTF-8 characters) from either end of a UTF-8 string.
Please feel free to give me your comments since I'm not sure this implimentation is correct. (Maybe this implementation trims too aggressively.)

BUG=7377
Review URL: http://codereview.chromium.org/20219

git-svn-id: svn://svn.chromium.org/chrome/trunk/src@10456 0039d316-1c4b-4281-b951-d872f2087c98

3 files changed, 85 insertions, 7 deletions

diff --git a/base/string_util.cc b/base/string_util.cc
index 4ba8c4b..55be9df 100644
--- a/base/string_util.cc
+++ b/base/string_util.cc
@@ -337,8 +337,6 @@ const char kWhitespaceASCII[] = {
   0x0C,
   0x0D,
   0x20,    // Space
-  '\x85',  // <control-0085>
-  '\xa0',  // No-Break Space
   0
 };
 const char* const kCodepageUTF8 = "UTF-8";
@@ -393,10 +391,32 @@ TrimPositions TrimWhitespace(const std::wstring& input,
   return TrimStringT(input, kWhitespaceWide, positions, output);
 }
 
+TrimPositions TrimWhitespaceASCII(const std::string& input,
+                                  TrimPositions positions,
+                                  std::string* output) {
+  return TrimStringT(input, kWhitespaceASCII, positions, output);
+}
+
+TrimPositions TrimWhitespaceUTF8(const std::string& input,
+                                 TrimPositions positions,
+                                 std::string* output) {
+  // This implementation is not so fast since it converts the text encoding
+  // twice. Please feel free to file a bug if this function hurts the
+  // performance of Chrome.
+  DCHECK(IsStringUTF8(input));
+  std::wstring input_wide = UTF8ToWide(input);
+  std::wstring output_wide;
+  TrimPositions result = TrimWhitespace(input_wide, positions, &output_wide);
+  *output = WideToUTF8(output_wide);
+  return result;
+}
+
+// This function is only for backward-compatibility.
+// To be removed when all callers are updated.
 TrimPositions TrimWhitespace(const std::string& input,
                              TrimPositions positions,
                              std::string* output) {
-  return TrimStringT(input, kWhitespaceASCII, positions, output);
+  return TrimWhitespaceASCII(input, positions, output);
 }
 
 std::wstring CollapseWhitespace(const std::wstring& text,
diff --git a/base/string_util.h b/base/string_util.h
index 500a114..64e724e 100644
--- a/base/string_util.h
+++ b/base/string_util.h
@@ -128,9 +128,13 @@ bool TrimString(const std::string& input,
                 std::string* output);
 
 // Trims any whitespace from either end of the input string.  Returns where
-// whitespace was found.  The non-wide version of this function only looks for
-// ASCII whitespace; UTF-8 code-points are not searched for (use the wide
-// version instead).
+// whitespace was found.
+// The non-wide version has two functions:
+// * TrimWhitespaceASCII()
+//   This function is for ASCII strings and only looks for ASCII whitespace;
+// * TrimWhitespaceUTF8()
+//   This function is for UTF-8 strings and looks for Unicode whitespace.
+// Please choose the best one according to your usage.
 // NOTE: Safe to use the same variable for both input and output.
 enum TrimPositions {
   TRIM_NONE     = 0,
@@ -141,6 +145,15 @@ enum TrimPositions {
 TrimPositions TrimWhitespace(const std::wstring& input,
                              TrimPositions positions,
                              std::wstring* output);
+TrimPositions TrimWhitespaceASCII(const std::string& input,
+                                  TrimPositions positions,
+                                  std::string* output);
+TrimPositions TrimWhitespaceUTF8(const std::string& input,
+                                 TrimPositions positions,
+                                 std::string* output);
+
+// Deprecated. This function is only for backward compatibility and calls
+// TrimWhitespaceASCII().
 TrimPositions TrimWhitespace(const std::string& input,
                              TrimPositions positions,
                              std::string* output);
diff --git a/base/string_util_unittest.cc b/base/string_util_unittest.cc
index 2b7634f..c5fdb2c 100644
--- a/base/string_util_unittest.cc
+++ b/base/string_util_unittest.cc
@@ -49,7 +49,6 @@ static const struct trim_case_ascii {
   {"  ", TRIM_TRAILING, "", TRIM_TRAILING},
   {"  ", TRIM_ALL, "", TRIM_ALL},
   {"\t\rTest String\n", TRIM_ALL, "Test String", TRIM_ALL},
-  {"\x85Test String\xa0\x20", TRIM_ALL, "Test String", TRIM_ALL},
 };
 
 TEST(StringUtilTest, TrimWhitespace) {
@@ -80,6 +79,52 @@ TEST(StringUtilTest, TrimWhitespace) {
   }
 }
 
+static const struct trim_case_utf8 {
+  const char* input;
+  const TrimPositions positions;
+  const char* output;
+  const TrimPositions return_value;
+} trim_cases_utf8[] = {
+  // UTF-8 strings that start (and end) with Unicode space characters
+  // (including zero-width spaces).
+  {"\xE2\x80\x80Test String\xE2\x80\x81", TRIM_ALL, "Test String", TRIM_ALL},
+  {"\xE2\x80\x82Test String\xE2\x80\x83", TRIM_ALL, "Test String", TRIM_ALL},
+  {"\xE2\x80\x84Test String\xE2\x80\x85", TRIM_ALL, "Test String", TRIM_ALL},
+  {"\xE2\x80\x86Test String\xE2\x80\x87", TRIM_ALL, "Test String", TRIM_ALL},
+  {"\xE2\x80\x88Test String\xE2\x80\x8A", TRIM_ALL, "Test String", TRIM_ALL},
+  {"\xE3\x80\x80Test String\xE3\x80\x80", TRIM_ALL, "Test String", TRIM_ALL},
+  // UTF-8 strings that end with 0x85 (NEL in ISO-8859).
+  {"\xD0\x85", TRIM_TRAILING, "\xD0\x85", TRIM_NONE},
+  {"\xD9\x85", TRIM_TRAILING, "\xD9\x85", TRIM_NONE},
+  {"\xEC\x97\x85", TRIM_TRAILING, "\xEC\x97\x85", TRIM_NONE},
+  {"\xF0\x90\x80\x85", TRIM_TRAILING, "\xF0\x90\x80\x85", TRIM_NONE},
+  // UTF-8 strings that end with 0xA0 (non-break space in ISO-8859-1).
+  {"\xD0\xA0", TRIM_TRAILING, "\xD0\xA0", TRIM_NONE},
+  {"\xD9\xA0", TRIM_TRAILING, "\xD9\xA0", TRIM_NONE},
+  {"\xEC\x97\xA0", TRIM_TRAILING, "\xEC\x97\xA0", TRIM_NONE},
+  {"\xF0\x90\x80\xA0", TRIM_TRAILING, "\xF0\x90\x80\xA0", TRIM_NONE},
+};
+
+TEST(StringUtilTest, TrimWhitespaceUTF8) {
+  std::string output_ascii;
+  for (size_t i = 0; i < arraysize(trim_cases_ascii); ++i) {
+    const trim_case_ascii& value = trim_cases_ascii[i];
+    EXPECT_EQ(value.return_value,
+              TrimWhitespaceASCII(value.input, value.positions, &output_ascii));
+    EXPECT_EQ(value.output, output_ascii);
+  }
+
+  // Test that TrimWhiteSpaceUTF8() can remove Unicode space characters and
+  // prevent from removing UTF-8 characters that end with an ISO-8859 NEL.
+  std::string output_utf8;
+  for (size_t i = 0; i < arraysize(trim_cases_utf8); ++i) {
+    const trim_case_utf8& value = trim_cases_utf8[i];
+    EXPECT_EQ(value.return_value,
+              TrimWhitespaceUTF8(value.input, value.positions, &output_utf8));
+    EXPECT_EQ(value.output, output_utf8);
+  }
+}
+
 static const struct collapse_case {
   const wchar_t* input;
   const bool trim;