From fa6e10ea6a87127ae813a708ccc97e708982f93f Mon Sep 17 00:00:00 2001
From: Eelco Dolstra <edolstra@gmail.com>
Date: Fri, 23 May 2025 23:33:59 +0200
Subject: [PATCH 1/3] Don't use 'callback' object that we may have moved out of

---
 src/libstore/http-binary-cache-store.cc | 6 +++---
 1 file changed, 3 insertions(+), 3 deletions(-)

diff --git a/src/libstore/http-binary-cache-store.cc b/src/libstore/http-binary-cache-store.cc
index 2b591dda9..e44d146b9 100644
--- a/src/libstore/http-binary-cache-store.cc
+++ b/src/libstore/http-binary-cache-store.cc
@@ -176,13 +176,13 @@ protected:
     void getFile(const std::string & path,
         Callback<std::optional<std::string>> callback) noexcept override
     {
+        auto callbackPtr = std::make_shared<decltype(callback)>(std::move(callback));
+
         try {
             checkEnabled();
 
             auto request(makeRequest(path));
 
-            auto callbackPtr = std::make_shared<decltype(callback)>(std::move(callback));
-
             getFileTransfer()->enqueueFileTransfer(request,
                 {[callbackPtr, this](std::future<FileTransferResult> result) {
                     try {
@@ -198,7 +198,7 @@ protected:
             }});
 
         } catch (...) {
-            callback.rethrow();
+            callbackPtr->rethrow();
             return;
         }
     }

From d877b0c0cc4795d17d10b9b9039f2de828152c55 Mon Sep 17 00:00:00 2001
From: Eelco Dolstra <edolstra@gmail.com>
Date: Sat, 24 May 2025 00:14:32 +0200
Subject: [PATCH 2/3] fromStructuredAttrs(): Don't crash if
 exportReferencesGraph is a string

Fixes

  error: [json.exception.type_error.302] type must be array, but is string

and other crashes.

Fixes #13254.
---
 src/libstore/derivation-options.cc | 9 +++++++--
 src/libstore/misc.cc               | 2 ++
 2 files changed, 9 insertions(+), 2 deletions(-)

diff --git a/src/libstore/derivation-options.cc b/src/libstore/derivation-options.cc
index e031f8447..f6bac2868 100644
--- a/src/libstore/derivation-options.cc
+++ b/src/libstore/derivation-options.cc
@@ -211,8 +211,13 @@ DerivationOptions::fromStructuredAttrs(const StringMap & env, const StructuredAt
                     auto e = optionalValueAt(parsed->structuredAttrs, "exportReferencesGraph");
                     if (!e || !e->is_object())
                         return ret;
-                    for (auto & [key, storePathsJson] : getObject(*e)) {
-                        ret.insert_or_assign(key, storePathsJson);
+                    for (auto & [key, value] : getObject(*e)) {
+                        if (value.is_array())
+                            ret.insert_or_assign(key, value);
+                        else if (value.is_string())
+                            ret.insert_or_assign(key, StringSet{value});
+                        else
+                            throw Error("'exportReferencesGraph' value is not an array or a string");
                     }
                 } else {
                     auto s = getOr(env, "exportReferencesGraph", "");
diff --git a/src/libstore/misc.cc b/src/libstore/misc.cc
index 967c91d72..dabae647f 100644
--- a/src/libstore/misc.cc
+++ b/src/libstore/misc.cc
@@ -225,6 +225,8 @@ void Store::queryMissing(const std::vector<DerivedPath> & targets,
             auto parsedDrv = StructuredAttrs::tryParse(drv->env);
             DerivationOptions drvOptions;
             try {
+                // FIXME: this is a lot of work just to get the value
+                // of `allowSubstitutes`.
                 drvOptions = DerivationOptions::fromStructuredAttrs(
                     drv->env,
                     parsedDrv ? &*parsedDrv : nullptr);

From c66eb9cef77c3462d0324b258d0c5e0b8e4f4e7f Mon Sep 17 00:00:00 2001
From: Eelco Dolstra <edolstra@gmail.com>
Date: Sat, 24 May 2025 00:40:06 +0200
Subject: [PATCH 3/3] Add test

---
 tests/functional/structured-attrs-shell.nix | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/tests/functional/structured-attrs-shell.nix b/tests/functional/structured-attrs-shell.nix
index a819e39cd..e9b9f1e39 100644
--- a/tests/functional/structured-attrs-shell.nix
+++ b/tests/functional/structured-attrs-shell.nix
@@ -21,7 +21,7 @@ mkDerivation {
     "b"
     "c"
   ];
-  exportReferencesGraph.refs = [ dep ];
+  exportReferencesGraph.refs = dep;
   buildCommand = ''
     touch ''${outputs[out]}; touch ''${outputs[dev]}
   '';