eachToTuple: use to<fbstring>(delim) instead of delim

Summary: eachToTuple: use to<fbstring>(delim) instead of delim

Reviewed By: yfeldblum

Differential Revision: D16419866

fbshipit-source-id: 7a57f41ea210c569284f6c619784adc95f03b26e

folly/gen/String.h

@@ -150,7 +150,8 @@ detail::Map<detail::SplitTo<std::tuple<Targets...>, fbstring, Targets...>>
 eachToTuple(StringPiece delim) {
   return detail::Map<
       detail::SplitTo<std::tuple<Targets...>, fbstring, Targets...>>(
-      detail::SplitTo<std::tuple<Targets...>, fbstring, Targets...>(delim));
+      detail::SplitTo<std::tuple<Targets...>, fbstring, Targets...>(
+          to<fbstring>(delim)));
 }
 
 template <class First, class Second>

folly/gen/test/StringTest.cpp

@@ -190,6 +190,21 @@ TEST(StringGen, EachToTuple) {
     };
     EXPECT_EQ(expected, actual);
   }
+  {
+    // StringPiece target
+    auto lines = "1::cat 2::dog";
+    // clang-format off
+    auto actual
+      = split(lines, ' ')
+      | eachToTuple<int, StringPiece>("::")
+      | as<vector>();
+    // clang-format on
+    vector<tuple<int, StringPiece>> expected{
+        make_tuple(1, "cat"),
+        make_tuple(2, "dog"),
+    };
+    EXPECT_EQ(expected, actual);
+  }
   {
     // Empty field
     auto lines = "2:tjackson:4 3::5";