From f2522d4ecdcd693a2f94cd118eb7fa509983a54e Mon Sep 17 00:00:00 2001
From: Robert Hensing <robert@roberthensing.nl>
Date: Mon, 8 Apr 2024 13:14:03 +0200
Subject: [PATCH] libexpr-c: Add nix_store_path_name

---
 src/libstore-c/nix_api_store.cc    | 7 +++++++
 src/libstore-c/nix_api_store.h     | 9 +++++++++
 tests/unit/libexpr/nix_api_expr.cc | 8 ++++++--
 3 files changed, 22 insertions(+), 2 deletions(-)

diff --git a/src/libstore-c/nix_api_store.cc b/src/libstore-c/nix_api_store.cc
index d044ba14f..511ba0fad 100644
--- a/src/libstore-c/nix_api_store.cc
+++ b/src/libstore-c/nix_api_store.cc
@@ -128,6 +128,13 @@ nix_err nix_store_realise(
     NIXC_CATCH_ERRS
 }
 
+void nix_store_path_name(const StorePath *store_path, void * callback, void * user_data)
+{
+    std::string_view name = store_path->path.name();
+    ((nix_get_string_callback) callback)(name.data(), name.size(), user_data);
+}
+
+
 void nix_store_path_free(StorePath * sp)
 {
     delete sp;
diff --git a/src/libstore-c/nix_api_store.h b/src/libstore-c/nix_api_store.h
index ab86a81df..ca8996681 100644
--- a/src/libstore-c/nix_api_store.h
+++ b/src/libstore-c/nix_api_store.h
@@ -90,6 +90,15 @@ nix_err nix_store_get_uri(nix_c_context * context, Store * store, void * callbac
  */
 StorePath * nix_store_parse_path(nix_c_context * context, Store * store, const char * path);
 
+/**
+ * @brief Get the path name (e.g. "name" in /nix/store/...-name)
+ *
+ * @param[in] store_path the path to get the name from
+ * @param[in] callback called with the name
+ * @param[in] user_data arbitrary data, passed to the callback when it's called.
+ */
+void nix_store_path_name(const StorePath *store_path, void * callback, void * user_data);
+
 /**
  * @brief Copy a StorePath
  *
diff --git a/tests/unit/libexpr/nix_api_expr.cc b/tests/unit/libexpr/nix_api_expr.cc
index fad078d0c..f5c66536d 100644
--- a/tests/unit/libexpr/nix_api_expr.cc
+++ b/tests/unit/libexpr/nix_api_expr.cc
@@ -6,6 +6,7 @@
 #include "nix_api_value.h"
 
 #include "tests/nix_api_expr.hh"
+#include "tests/string_callback.hh"
 
 #include "gmock/gmock.h"
 #include <gtest/gtest.h>
@@ -168,11 +169,14 @@ TEST_F(nix_api_expr_test, nix_expr_realise_context)
     EXPECT_THAT(s, testing::HasSubstr("a derivation path by itself:"));
     EXPECT_THAT(s, testing::EndsWith("-not-actually-built-yet.drv\n"));
 
-    std::vector<std::string_view> names;
+    std::vector<std::string> names;
     size_t n = nix_realised_string_get_store_path_count(r);
     for (size_t i = 0; i < n; ++i) {
         const StorePath * p = nix_realised_string_get_store_path(r, i);
-        names.push_back(p->path.name());
+        ASSERT_NE(nullptr, p);
+        std::string name;
+        nix_store_path_name(p, OBSERVE_STRING(name));
+        names.push_back(name);
     }
     std::sort(names.begin(), names.end());
     ASSERT_EQ(3, names.size());