From 65346dc54d5326786b3ff055a14eadef2104fb81 Mon Sep 17 00:00:00 2001
From: Bronek Kozicki <brok@incorrekt.com>
Date: Wed, 25 Oct 2023 18:07:18 +0000
Subject: [PATCH 1/3] Remove include <ranges>

---
 src/test/jtx/TestHelpers.h | 14 +++++++++++---
 1 file changed, 11 insertions(+), 3 deletions(-)

diff --git a/src/test/jtx/TestHelpers.h b/src/test/jtx/TestHelpers.h
index 2bee47a6411..7b4cae51554 100644
--- a/src/test/jtx/TestHelpers.h
+++ b/src/test/jtx/TestHelpers.h
@@ -27,17 +27,25 @@
 #include <ripple/protocol/jss.h>
 #include <test/jtx/Env.h>
 
-#include <ranges>
+#include <vector>
 
 namespace ripple {
 namespace test {
 namespace jtx {
 
 // Helper to make vector from iterable
+template <typename T>
+concept iterable = requires(T& v) {
+                       std::begin(v);
+                       std::end(v);
+                   };
+
+template <typename Input>
 auto
-make_vector(auto const& input) requires std::ranges::range<decltype(input)>
+make_vector(Input const& input)
+    requires iterable<Input>
 {
-    return std::vector(std::ranges::begin(input), std::ranges::end(input));
+    return std::vector(std::begin(input), std::end(input));
 }
 
 // Functions used in debugging

From ee53c5ddff12b94b67c41361838ba93002da02a3 Mon Sep 17 00:00:00 2001
From: Bronek Kozicki <brok@incorrekt.com>
Date: Wed, 25 Oct 2023 18:17:10 +0000
Subject: [PATCH 2/3] Formatting fix

---
 src/test/jtx/TestHelpers.h | 12 ++++++------
 1 file changed, 6 insertions(+), 6 deletions(-)

diff --git a/src/test/jtx/TestHelpers.h b/src/test/jtx/TestHelpers.h
index 7b4cae51554..61d0eb87f9f 100644
--- a/src/test/jtx/TestHelpers.h
+++ b/src/test/jtx/TestHelpers.h
@@ -35,15 +35,15 @@ namespace jtx {
 
 // Helper to make vector from iterable
 template <typename T>
-concept iterable = requires(T& v) {
-                       std::begin(v);
-                       std::end(v);
-                   };
+concept iterable = requires(T& v)
+{
+    std::begin(v);
+    std::end(v);
+};
 
 template <typename Input>
 auto
-make_vector(Input const& input)
-    requires iterable<Input>
+make_vector(Input const& input) requires iterable<Input>
 {
     return std::vector(std::begin(input), std::end(input));
 }

From 5b425a52ca09b6aa95d0e8d514c2831c467c1702 Mon Sep 17 00:00:00 2001
From: Bronek Kozicki <brok@incorrekt.com>
Date: Mon, 30 Oct 2023 15:24:37 +0000
Subject: [PATCH 3/3] Remove named concept iterable

---
 src/test/jtx/TestHelpers.h | 16 ++++++++--------
 1 file changed, 8 insertions(+), 8 deletions(-)

diff --git a/src/test/jtx/TestHelpers.h b/src/test/jtx/TestHelpers.h
index 61d0eb87f9f..b065cec470a 100644
--- a/src/test/jtx/TestHelpers.h
+++ b/src/test/jtx/TestHelpers.h
@@ -33,17 +33,17 @@ namespace ripple {
 namespace test {
 namespace jtx {
 
-// Helper to make vector from iterable
-template <typename T>
-concept iterable = requires(T& v)
+// TODO We only need this long "requires" clause as polyfill, for C++20
+// implementations which are missing <ranges> header. Replace with
+// `std::ranges::range<Input>`, and accordingly use std::ranges::begin/end
+// when we have moved to better compilers.
+template <typename Input>
+auto
+make_vector(Input const& input) requires requires(Input& v)
 {
     std::begin(v);
     std::end(v);
-};
-
-template <typename Input>
-auto
-make_vector(Input const& input) requires iterable<Input>
+}
 {
     return std::vector(std::begin(input), std::end(input));
 }