Make config keep the absolute root to load relative files from

This means Config::get_path will continue to work even if we change
current directory in the process (when the path the config was loaded
from was relative).

2 files changed, 12 insertions, 1 deletions

diff --git a/src/config.cc b/src/config.cc
index 4d7cf52..515c1eb 100644
--- a/src/config.cc
+++ b/src/config.cc
@@ -128,7 +128,8 @@ std::unique_ptr<Config> load(Logger* logger,
                  path.c_str(), strerror(errno));
     return nullptr;
   }
-  auto root = path.parent_path();
+  std::error_code err;
+  auto root = std::filesystem::absolute(path.parent_path(), err);
   std::unordered_map<std::string, std::string> data;
   std::string line;
   unsigned long num = 0;
diff --git a/test/test_config.cc b/test/test_config.cc
index d9ddf3a..bcb7b59 100644
--- a/test/test_config.cc
+++ b/test/test_config.cc
@@ -165,3 +165,13 @@ TEST_F(ConfigTest, path) {
   EXPECT_EQ("/file", cfg->get_path("absolute", ""));
   EXPECT_EQ(path().parent_path() / "file", cfg->get_path("relative", ""));
 }
+
+TEST_F(ConfigTest, path_when_load_relative) {
+  write("absolute = /file\n"
+        "relative = file\n");
+  auto cfg = Config::create(logger(), std::filesystem::relative(path()));
+  ASSERT_TRUE(cfg);
+  EXPECT_EQ("/file", cfg->get_path("absolute", ""));
+  EXPECT_EQ(path().parent_path() / "file",
+            std::filesystem::weakly_canonical(cfg->get_path("relative", "")));
+}