intermediate changes

ref:cde9a383711a11544ce7e107a78147fb96cc4029

1 files changed, 39 insertions, 0 deletions

diff --git a/library/cpp/testing/common/scope.h b/library/cpp/testing/common/scope.h
new file mode 100644
index 0000000000..a2ca0e77e4
--- /dev/null
+++ b/library/cpp/testing/common/scope.h
@@ -0,0 +1,39 @@
+#pragma once
+
+#include <util/generic/string.h>
+#include <util/generic/vector.h>
+#include <util/system/env.h>
+
+#include <utility>
+
+namespace NTesting {
+    // @brief Assigns new values to the given environment variables and restores old values upon destruction.
+    // @note if there was no env variable with given name, it will be set to empty string upon destruction IGNIETFERRO-1486
+    struct TScopedEnvironment {
+        TScopedEnvironment(const TString& name, const TString& value)
+            : PreviousState{1, {name, ::GetEnv(name)}}
+        {
+            ::SetEnv(name, value);
+        }
+
+        TScopedEnvironment(const TVector<std::pair<TString, TString>>& vars)
+            : PreviousState(Reserve(vars.size()))
+        {
+            for (const auto& [k, v] : vars) {
+                PreviousState.emplace_back(k, ::GetEnv(k));
+                ::SetEnv(k, v);
+            }
+        }
+
+        ~TScopedEnvironment() {
+            for (const auto& [k, v] : PreviousState) {
+                ::SetEnv(k, v);
+            }
+        }
+
+        TScopedEnvironment(const TScopedEnvironment&) = delete;
+        TScopedEnvironment& operator=(const TScopedEnvironment&) = delete;
+    private:
+        TVector<std::pair<TString, TString>> PreviousState;
+    };
+}