From f3d2a16eff5c88d35c774315f08e260697b646f1 Mon Sep 17 00:00:00 2001
From: Robert Hensing <robert@roberthensing.nl>
Date: Mon, 25 Mar 2024 12:43:30 +0100
Subject: [PATCH] Fix evalState::rootFS paths' to_string()

This showPath is getting a little too ad hoc, but it works for now.
---
 src/libexpr/eval.cc            | 1 +
 src/libutil/source-accessor.cc | 4 +++-
 2 files changed, 4 insertions(+), 1 deletion(-)

diff --git a/src/libexpr/eval.cc b/src/libexpr/eval.cc
index 8020b3b31..0e7937d17 100644
--- a/src/libexpr/eval.cc
+++ b/src/libexpr/eval.cc
@@ -315,6 +315,7 @@ EvalState::EvalState(
 {
     corepkgsFS->setPathDisplay("<nix", ">");
     internalFS->setPathDisplay("«nix-internal»", "");
+    rootFS->setPathDisplay("/", "");
 
     countCalls = getEnv("NIX_COUNT_CALLS").value_or("0") != "0";
 
diff --git a/src/libutil/source-accessor.cc b/src/libutil/source-accessor.cc
index 484190c9b..422b3f3eb 100644
--- a/src/libutil/source-accessor.cc
+++ b/src/libutil/source-accessor.cc
@@ -64,7 +64,9 @@ void SourceAccessor::setPathDisplay(std::string displayPrefix, std::string displ
 
 std::string SourceAccessor::showPath(const CanonPath & path)
 {
-    return displayPrefix + (displayPrefix.empty() ? "" : ":") + path.rel() + displaySuffix;
+    return displayPrefix
+        + ((displayPrefix.empty() || displayPrefix.ends_with("/")) ? "" : ":") + path.rel()
+        + displaySuffix;
 }
 
 CanonPath SourceAccessor::resolveSymlinks(