When input is "" (or " " with trim_whitespace true), SplitString() should return an empty vector, not a vector of one empty string.

Brett and I discussed this for a while and felt this would be wise, whereas dropping all empty segments entirely (e.g. converting "a,,b" to a vector of two elements instead of three) was probably unwise. 

This also simplifies the code some. 

Fixing this also required changing the code in mime_util.cc to handle empty vectors to "are codecs valid" oracle functions (in which case we return false). I also fixed some style issues there. It also required avoiding passing the empty string in a test in extension_api_unittest.cc; Aaron assures me that this code is not expected to be defensive against such inputs, but at his suggestion I also added some CHECK()s to the API.

BUG=none
TEST=none
Review URL: https://chromiumcodereview.appspot.com/9960004

git-svn-id: svn://svn.chromium.org/chrome/trunk/src@129998 0039d316-1c4b-4281-b951-d872f2087c98

1 files changed, 12 insertions, 9 deletions

diff --git a/base/string_split_unittest.cc b/base/string_split_unittest.cc
index 83e4d74..5d4dafe 100644
--- a/base/string_split_unittest.cc
+++ b/base/string_split_unittest.cc
@@ -1,4 +1,4 @@
-// Copyright (c) 2011 The Chromium Authors. All rights reserved.
+// Copyright (c) 2012 The Chromium Authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
@@ -163,8 +163,7 @@ TEST(StringUtilTest, SplitString) {
   std::vector<std::wstring> r;
 
   SplitString(L"", L',', &r);
-  ASSERT_EQ(1U, r.size());
-  EXPECT_EQ(r[0], L"");
+  EXPECT_EQ(0U, r.size());
   r.clear();
 
   SplitString(L"a,b,c", L',', &r);
@@ -188,9 +187,8 @@ TEST(StringUtilTest, SplitString) {
   EXPECT_EQ(r[2], L"c");
   r.clear();
 
-  SplitString(L"", L'*', &r);
-  ASSERT_EQ(1U, r.size());
-  EXPECT_EQ(r[0], L"");
+  SplitString(L"   ", L'*', &r);
+  EXPECT_EQ(0U, r.size());
   r.clear();
 
   SplitString(L"foo", L'*', &r);
@@ -266,12 +264,17 @@ TEST(SplitStringUsingSubstrTest, TrailingDelimitersSkipped) {
 TEST(StringSplitTest, StringSplitDontTrim) {
   std::vector<std::string> r;
 
-  SplitStringDontTrim("\t\ta\t", '\t', &r);
+  SplitStringDontTrim("   ", '*', &r);
+  ASSERT_EQ(1U, r.size());
+  EXPECT_EQ(r[0], "   ");
+  r.clear();
+
+  SplitStringDontTrim("\t  \ta\t ", '\t', &r);
   ASSERT_EQ(4U, r.size());
   EXPECT_EQ(r[0], "");
-  EXPECT_EQ(r[1], "");
+  EXPECT_EQ(r[1], "  ");
   EXPECT_EQ(r[2], "a");
-  EXPECT_EQ(r[3], "");
+  EXPECT_EQ(r[3], " ");
   r.clear();
 
   SplitStringDontTrim("\ta\t\nb\tcc", '\n', &r);