Added StringPiece overloads for base::JoinString.

base/strings/string_util_unittest.cc

Index: base/strings/string_util_unittest.cc
diff --git a/base/strings/string_util_unittest.cc b/base/strings/string_util_unittest.cc
index df2226e48bc488f37b628ed002cfc790bad11b7a..7738a4e25e50464ba1547a1a79490397a6aa92f5 100644
--- a/base/strings/string_util_unittest.cc
+++ b/base/strings/string_util_unittest.cc
@@ -707,6 +707,47 @@ TEST(StringUtilTest, JoinString16) {
   EXPECT_EQ(ASCIIToUTF16("a|b|c|| "), JoinString(parts, ASCIIToUTF16("|")));
 }
 
+TEST(StringUtilTest, JoinStringPiece) {
+  std::string separator(", ");
+  std::vector<base::StringPiece> parts;
+  EXPECT_EQ(base::StringPiece(), JoinStringPiece(parts, separator));
+
+  parts.push_back("a");
+  EXPECT_EQ("a", JoinStringPiece(parts, separator));
+
+  parts.push_back("b");
+  parts.push_back("c");
+  EXPECT_EQ("a, b, c", JoinStringPiece(parts, separator));
+
+  parts.push_back(base::StringPiece());
+  EXPECT_EQ("a, b, c, ", JoinStringPiece(parts, separator));
+  parts.push_back(" ");
+  EXPECT_EQ("a|b|c|| ", JoinStringPiece(parts, "|"));
+}
+
+TEST(StringUtilTest, JoinStringPiece16) {
+  string16 separator = ASCIIToUTF16(", ");
+  std::vector<base::StringPiece16> parts;
+  EXPECT_EQ(base::StringPiece16(), JoinStringPiece(parts, separator));
+
+  const string16 kA = ASCIIToUTF16("a");
+  parts.push_back(kA);
+  EXPECT_EQ(ASCIIToUTF16("a"), JoinStringPiece(parts, separator));
+
+  const string16 kB = ASCIIToUTF16("b");
+  parts.push_back(kB);
+  const string16 kC = ASCIIToUTF16("c");
+  parts.push_back(kC);
+  EXPECT_EQ(ASCIIToUTF16("a, b, c"), JoinStringPiece(parts, separator));
+
+  parts.push_back(base::StringPiece16());
+  EXPECT_EQ(ASCIIToUTF16("a, b, c, "), JoinStringPiece(parts, separator));
+  const string16 kSpace = ASCIIToUTF16(" ");
+  parts.push_back(kSpace);
+  EXPECT_EQ(ASCIIToUTF16("a|b|c|| "),
+            JoinStringPiece(parts, ASCIIToUTF16("|")));
+}
+
 TEST(StringUtilTest, StartsWith) {
   EXPECT_TRUE(StartsWith("javascript:url", "javascript",
                          base::CompareCase::SENSITIVE));