1 files changed, 60 insertions, 0 deletions
diff --git a/pkgs/test/dotnet/use-dotnet-from-env/default.nix b/pkgs/test/dotnet/use-dotnet-from-env/default.nix
new file mode 100644
index 0000000000000..711a98eb0c29d
--- /dev/null
+++ b/pkgs/test/dotnet/use-dotnet-from-env/default.nix
@@ -0,0 +1,60 @@
+{ lib
+, dotnet-sdk
+, buildPackages # buildDotnetModule, dotnet-runtime
+, testers
+, runCommand
+, removeReferencesTo
+}:
+let
+  inherit (buildPackages) buildDotnetModule dotnet-runtime;
+
+  app = buildDotnetModule {
+    name = "use-dotnet-from-env-test-application";
+    src = ./src;
+    nugetDeps = ./nuget-deps.nix;
+    useDotnetFromEnv = true;
+    env.TargetFramework = "net${lib.versions.majorMinor (lib.getVersion dotnet-sdk)}";
+  };
+
+  appWithoutFallback = app.overrideAttrs (oldAttrs: {
+    nativeBuildInputs = (oldAttrs.nativeBuildInputs or [ ]) ++ [
+      removeReferencesTo
+    ];
+    postFixup = (oldAttrs.postFixup or "") + ''
+      remove-references-to -t ${dotnet-runtime} "$out/bin/Application"
+    '';
+  });
+
+  runtimeVersion = lib.getVersion dotnet-runtime;
+  runtimeVersionFile = builtins.toFile "dotnet-version.txt" runtimeVersion;
+in
+{
+  fallback = testers.testEqualContents {
+    assertion = "buildDotnetModule sets fallback DOTNET_ROOT in wrapper";
+    expected = runtimeVersionFile;
+    actual = runCommand "use-dotnet-from-env-fallback-test" { } ''
+      ${app}/bin/Application >"$out"
+    '';
+  };
+
+  # Check that appWithoutFallback does not use fallback .NET runtime.
+  without-fallback = testers.testBuildFailure (runCommand "use-dotnet-from-env-without-fallback-test" { } ''
+    ${appWithoutFallback}/bin/Application >"$out"
+  '');
+
+  # NB assumes that without-fallback above to passes.
+  use-dotnet-root-env = testers.testEqualContents {
+    assertion = "buildDotnetModule uses DOTNET_ROOT from environment in wrapper";
+    expected = runtimeVersionFile;
+    actual = runCommand "use-dotnet-from-env-root-test" { env.DOTNET_ROOT = dotnet-runtime; } ''
+      ${appWithoutFallback}/bin/Application >"$out"
+    '';
+  };
+  use-dotnet-path-env = testers.testEqualContents {
+    assertion = "buildDotnetModule uses DOTNET_ROOT from dotnet in PATH in wrapper";
+    expected = runtimeVersionFile;
+    actual = runCommand "use-dotnet-from-env-path-test" { dotnetRuntime = dotnet-runtime; } ''
+      PATH=$dotnetRuntime''${PATH+:}$PATH ${appWithoutFallback}/bin/Application >"$out"
+    '';
+  };
+}