From 37ce2f1fe11ca27fc04b14795a2340ed1654a4ef Mon Sep 17 00:00:00 2001
From: Matthew Andres Moreno <mmore500.login+gpg@gmail.com>
Date: Thu, 13 Oct 2022 17:28:10 -0700
Subject: [PATCH] Implement separated stream helper

---
 include/uitsl/utility/SeparatedStream.hpp | 40 +++++++++++++++++++++++
 include/uitsl/utility/SetSeparator.hpp    | 31 ++++++++++++++++++
 tests/uitsl/utility/Makefile              |  1 +
 tests/uitsl/utility/SetSeparator.cpp      | 24 ++++++++++++++
 4 files changed, 96 insertions(+)
 create mode 100644 include/uitsl/utility/SeparatedStream.hpp
 create mode 100644 include/uitsl/utility/SetSeparator.hpp
 create mode 100644 tests/uitsl/utility/SetSeparator.cpp

diff --git a/include/uitsl/utility/SeparatedStream.hpp b/include/uitsl/utility/SeparatedStream.hpp
new file mode 100644
index 000000000..c267fa05b
--- /dev/null
+++ b/include/uitsl/utility/SeparatedStream.hpp
@@ -0,0 +1,40 @@
+#pragma once
+#ifndef UITSL_UTILITY_SEPARATEDSTREAM_HPP_INCLUDE
+#define UITSL_UTILITY_SEPARATEDSTREAM_HPP_INCLUDE
+
+#include <iostream>
+#include <string>
+#include <utility>
+
+namespace uitsl {
+
+// adapted from https://stackoverflow.com/a/30073885
+class SeparatedStream {
+
+  std::ostream& _stream;
+  std::string _sep;
+  bool _first;
+
+public:
+
+  SeparatedStream(std::ostream &stream, std::string sep)
+  : _stream(stream), _sep(std::move(sep)), _first(true) {}
+
+  template <class Rhs>
+  SeparatedStream &operator <<(Rhs &&rhs) {
+    if (_first) _first = false;
+    else _stream << _sep;
+    _stream << std::forward<Rhs>(rhs);
+    return *this;
+  }
+
+  SeparatedStream& operator<<(std::ostream &(*manip)(std::ostream&)) {
+    manip(_stream);
+    return *this;
+  }
+
+};
+
+} // namespace uitsl
+
+#endif // #ifndef UITSL_UTILITY_SEPARATEDSTREAM_HPP_INCLUDE
diff --git a/include/uitsl/utility/SetSeparator.hpp b/include/uitsl/utility/SetSeparator.hpp
new file mode 100644
index 000000000..8074c710c
--- /dev/null
+++ b/include/uitsl/utility/SetSeparator.hpp
@@ -0,0 +1,31 @@
+#pragma once
+#ifndef UITSL_UTILITY_SETSEPARATOR_HPP_INCLUDE
+#define UITSL_UTILITY_SETSEPARATOR_HPP_INCLUDE
+
+#include <iostream>
+#include <utility>
+#include <string>
+
+#include "SeparatedStream.hpp"
+
+namespace uitsl {
+
+// adapted from https://stackoverflow.com/a/30073885
+struct SetSeparator {
+
+  std::string sep;
+
+  SetSeparator(const std::string& sep) : sep(sep) {}
+
+};
+
+uitsl::SeparatedStream operator<<(
+  std::ostream& stream,
+  uitsl::SetSeparator wsep
+) {
+  return uitsl::SeparatedStream(stream, std::move(wsep.sep));
+}
+
+} // namespace uitsl
+
+#endif // #ifndef UITSL_UTILITY_SETSEPARATOR_HPP_INCLUDE
diff --git a/tests/uitsl/utility/Makefile b/tests/uitsl/utility/Makefile
index 580abbf90..805711c1a 100644
--- a/tests/uitsl/utility/Makefile
+++ b/tests/uitsl/utility/Makefile
@@ -2,6 +2,7 @@ TARGET_NAMES += get_exec_instance_uuid
 TARGET_NAMES += get_proc_instance_uuid
 TARGET_NAMES += get_thread_instance_uuid
 TARGET_NAMES += NamedArrayElement
+TARGET_NAMES += SetSeparator
 
 TO_ROOT := $(shell git rev-parse --show-cdup)
 
diff --git a/tests/uitsl/utility/SetSeparator.cpp b/tests/uitsl/utility/SetSeparator.cpp
new file mode 100644
index 000000000..316cddcad
--- /dev/null
+++ b/tests/uitsl/utility/SetSeparator.cpp
@@ -0,0 +1,24 @@
+#include <sstream>
+
+#include "Catch/single_include/catch2/catch.hpp"
+#include "stduuid/include/uuid.h"
+
+#include "uitsl/utility/SetSeparator.hpp"
+
+TEST_CASE("SetSeparator no items", "[nproc:1]") {
+  std::stringstream ss;
+  ss << uitsl::SetSeparator(", ");
+  REQUIRE(ss.str() == "");
+}
+
+TEST_CASE("SetSeparator one item", "[nproc:1]") {
+  std::stringstream ss;
+  ss << uitsl::SetSeparator(", ") << "hello";
+  REQUIRE(ss.str() == "hello");
+}
+
+TEST_CASE("SetSeparator two items", "[nproc:1]") {
+  std::stringstream ss;
+  ss << uitsl::SetSeparator(", ") << "hello" << "friend";
+  REQUIRE(ss.str() == "hello, friend");
+}