merge(3p/absl): subtree merge of Abseil up to e19260f r/1889

... notably, this includes Abseil's own StatusOr type, which
conflicted with our implementation (that was taken from TensorFlow).

Change-Id: Ie7d6764b64055caaeb8dc7b6b9d066291e6b538f

1 files changed, 38 insertions, 4 deletions

diff --git a/third_party/abseil_cpp/absl/strings/str_split.h b/third_party/abseil_cpp/absl/strings/str_split.h
index 1ce17f38aa81..bfbca422a8dc 100644
--- a/third_party/abseil_cpp/absl/strings/str_split.h
+++ b/third_party/abseil_cpp/absl/strings/str_split.h
@@ -369,6 +369,12 @@ struct SkipWhitespace {
   }
 };
 
+template <typename T>
+using EnableSplitIfString =
+    typename std::enable_if<std::is_same<T, std::string>::value ||
+                            std::is_same<T, const std::string>::value,
+                            int>::type;
+
 //------------------------------------------------------------------------------
 //                                  StrSplit()
 //------------------------------------------------------------------------------
@@ -489,22 +495,50 @@ struct SkipWhitespace {
 // Try not to depend on this distinction because the bug may one day be fixed.
 template <typename Delimiter>
 strings_internal::Splitter<
-    typename strings_internal::SelectDelimiter<Delimiter>::type, AllowEmpty>
+    typename strings_internal::SelectDelimiter<Delimiter>::type, AllowEmpty,
+    absl::string_view>
 StrSplit(strings_internal::ConvertibleToStringView text, Delimiter d) {
   using DelimiterType =
       typename strings_internal::SelectDelimiter<Delimiter>::type;
-  return strings_internal::Splitter<DelimiterType, AllowEmpty>(
+  return strings_internal::Splitter<DelimiterType, AllowEmpty,
+                                    absl::string_view>(
+      text.value(), DelimiterType(d), AllowEmpty());
+}
+
+template <typename Delimiter, typename StringType,
+          EnableSplitIfString<StringType> = 0>
+strings_internal::Splitter<
+    typename strings_internal::SelectDelimiter<Delimiter>::type, AllowEmpty,
+    std::string>
+StrSplit(StringType&& text, Delimiter d) {
+  using DelimiterType =
+      typename strings_internal::SelectDelimiter<Delimiter>::type;
+  return strings_internal::Splitter<DelimiterType, AllowEmpty, std::string>(
       std::move(text), DelimiterType(d), AllowEmpty());
 }
 
 template <typename Delimiter, typename Predicate>
 strings_internal::Splitter<
-    typename strings_internal::SelectDelimiter<Delimiter>::type, Predicate>
+    typename strings_internal::SelectDelimiter<Delimiter>::type, Predicate,
+    absl::string_view>
 StrSplit(strings_internal::ConvertibleToStringView text, Delimiter d,
          Predicate p) {
   using DelimiterType =
       typename strings_internal::SelectDelimiter<Delimiter>::type;
-  return strings_internal::Splitter<DelimiterType, Predicate>(
+  return strings_internal::Splitter<DelimiterType, Predicate,
+                                    absl::string_view>(
+      text.value(), DelimiterType(d), std::move(p));
+}
+
+template <typename Delimiter, typename Predicate, typename StringType,
+          EnableSplitIfString<StringType> = 0>
+strings_internal::Splitter<
+    typename strings_internal::SelectDelimiter<Delimiter>::type, Predicate,
+    std::string>
+StrSplit(StringType&& text, Delimiter d, Predicate p) {
+  using DelimiterType =
+      typename strings_internal::SelectDelimiter<Delimiter>::type;
+  return strings_internal::Splitter<DelimiterType, Predicate, std::string>(
       std::move(text), DelimiterType(d), std::move(p));
 }