From 93c51acfb5cdc28c4a44cc2ad86359b2b14528f0 Mon Sep 17 00:00:00 2001
From: Eelco Dolstra <edolstra@gmail.com>
Date: Mon, 24 Nov 2025 14:04:50 +0100
Subject: [PATCH] Add Setting<std::filesystem::path> specialization

Like PathSetting, this normalizes the path (without resolving
symlinks).
---
 src/libutil/configuration.cc                | 13 +++++++++++++
 src/libutil/include/nix/util/config-impl.hh |  1 +
 src/libutil/include/nix/util/logging.hh     |  4 ++--
 src/libutil/logging.cc                      |  2 +-
 4 files changed, 17 insertions(+), 3 deletions(-)

diff --git a/src/libutil/configuration.cc b/src/libutil/configuration.cc
index 7a0ed22ea..e520a6e38 100644
--- a/src/libutil/configuration.cc
+++ b/src/libutil/configuration.cc
@@ -433,6 +433,18 @@ std::string BaseSetting<StringMap>::to_string() const
         [](const auto & kvpair) { return kvpair.first + "=" + kvpair.second; });
 }
 
+template<>
+std::filesystem::path BaseSetting<std::filesystem::path>::parse(const std::string & str) const
+{
+    return std::filesystem::path(str).lexically_normal();
+}
+
+template<>
+std::string BaseSetting<std::filesystem::path>::to_string() const
+{
+    return value.string();
+}
+
 template class BaseSetting<int>;
 template class BaseSetting<unsigned int>;
 template class BaseSetting<long>;
@@ -445,6 +457,7 @@ template class BaseSetting<Strings>;
 template class BaseSetting<StringSet>;
 template class BaseSetting<StringMap>;
 template class BaseSetting<std::set<ExperimentalFeature>>;
+template class BaseSetting<std::filesystem::path>;
 
 static Path parsePath(const AbstractSetting & s, const std::string & str)
 {
diff --git a/src/libutil/include/nix/util/config-impl.hh b/src/libutil/include/nix/util/config-impl.hh
index f407bc862..6066765c5 100644
--- a/src/libutil/include/nix/util/config-impl.hh
+++ b/src/libutil/include/nix/util/config-impl.hh
@@ -134,6 +134,7 @@ DECLARE_CONFIG_SERIALISER(Strings)
 DECLARE_CONFIG_SERIALISER(StringSet)
 DECLARE_CONFIG_SERIALISER(StringMap)
 DECLARE_CONFIG_SERIALISER(std::set<ExperimentalFeature>)
+DECLARE_CONFIG_SERIALISER(std::filesystem::path)
 
 template<typename T>
 T BaseSetting<T>::parse(const std::string & str) const
diff --git a/src/libutil/include/nix/util/logging.hh b/src/libutil/include/nix/util/logging.hh
index 500d443e6..ec107304b 100644
--- a/src/libutil/include/nix/util/logging.hh
+++ b/src/libutil/include/nix/util/logging.hh
@@ -54,9 +54,9 @@ struct LoggerSettings : Config
           expression evaluation errors.
         )"};
 
-    Setting<Path> jsonLogPath{
+    Setting<std::filesystem::path> jsonLogPath{
         this,
-        "",
+        {},
         "json-log-path",
         R"(
           A file or unix socket to which JSON records of Nix's log output are
diff --git a/src/libutil/logging.cc b/src/libutil/logging.cc
index e2f28f553..48dc9e069 100644
--- a/src/libutil/logging.cc
+++ b/src/libutil/logging.cc
@@ -370,7 +370,7 @@ void applyJSONLogger()
     if (!loggerSettings.jsonLogPath.get().empty()) {
         try {
             std::vector<std::unique_ptr<Logger>> loggers;
-            loggers.push_back(makeJSONLogger(std::filesystem::path(loggerSettings.jsonLogPath.get()), false));
+            loggers.push_back(makeJSONLogger(loggerSettings.jsonLogPath.get(), false));
             try {
                 logger = makeTeeLogger(std::move(logger), std::move(loggers));
             } catch (...) {