From c48277c1c15f0b6be6a47271a6f8399fad96f7fd Mon Sep 17 00:00:00 2001
From: Yingchi Long <i@lyc.dev>
Date: Thu, 22 Jun 2023 18:19:42 +0800
Subject: [PATCH] libexpr: add tests for `nix::Value::print`

---
 src/libexpr/tests/value/print.cc | 170 +++++++++++++++++++++++++++++++
 1 file changed, 170 insertions(+)
 create mode 100644 src/libexpr/tests/value/print.cc

diff --git a/src/libexpr/tests/value/print.cc b/src/libexpr/tests/value/print.cc
new file mode 100644
index 000000000..2268658b2
--- /dev/null
+++ b/src/libexpr/tests/value/print.cc
@@ -0,0 +1,170 @@
+#include "tests/libexpr.hh"
+
+#include "value.hh"
+
+namespace nix {
+
+using namespace testing;
+
+struct ValuePrintingTests : LibExprTest
+{
+    template<class... A>
+    void test(Value v, std::string_view expected, A... args)
+    {
+        std::stringstream out;
+        v.print(state.symbols, out, args...);
+        ASSERT_EQ(out.str(), expected);
+    }
+};
+
+TEST_F(ValuePrintingTests, tInt)
+{
+    Value vInt;
+    vInt.mkInt(10);
+    test(vInt, "10");
+}
+
+TEST_F(ValuePrintingTests, tBool)
+{
+    Value vBool;
+    vBool.mkBool(true);
+    test(vBool, "true");
+}
+
+TEST_F(ValuePrintingTests, tString)
+{
+    Value vString;
+    vString.mkString("some-string");
+    test(vString, "\"some-string\"");
+}
+
+TEST_F(ValuePrintingTests, tPath)
+{
+    Value vPath;
+    vPath.mkString("/foo");
+    test(vPath, "\"/foo\"");
+}
+
+TEST_F(ValuePrintingTests, tNull)
+{
+    Value vNull;
+    vNull.mkNull();
+    test(vNull, "null");
+}
+
+TEST_F(ValuePrintingTests, tAttrs)
+{
+    Value vOne;
+    vOne.mkInt(1);
+
+    Value vTwo;
+    vTwo.mkInt(2);
+
+    BindingsBuilder builder(state, state.allocBindings(10));
+    builder.insert(state.symbols.create("one"), &vOne);
+    builder.insert(state.symbols.create("two"), &vTwo);
+
+    Value vAttrs;
+    vAttrs.mkAttrs(builder.finish());
+
+    test(vAttrs, "{ one = 1; two = 2; }");
+}
+
+TEST_F(ValuePrintingTests, tList)
+{
+    Value vOne;
+    vOne.mkInt(1);
+
+    Value vTwo;
+    vTwo.mkInt(2);
+
+    Value vList;
+    state.mkList(vList, 5);
+    vList.bigList.elems[0] = &vOne;
+    vList.bigList.elems[1] = &vTwo;
+    vList.bigList.size = 3;
+
+    test(vList, "[ 1 2 (nullptr) ]");
+}
+
+TEST_F(ValuePrintingTests, vThunk)
+{
+    Value vThunk;
+    vThunk.mkThunk(nullptr, nullptr);
+
+    test(vThunk, "<CODE>");
+}
+
+TEST_F(ValuePrintingTests, vApp)
+{
+    Value vApp;
+    vApp.mkApp(nullptr, nullptr);
+
+    test(vApp, "<CODE>");
+}
+
+TEST_F(ValuePrintingTests, vLambda)
+{
+    Value vLambda;
+    vLambda.mkLambda(nullptr, nullptr);
+
+    test(vLambda, "<LAMBDA>");
+}
+
+TEST_F(ValuePrintingTests, vPrimOp)
+{
+    Value vPrimOp;
+    vPrimOp.mkPrimOp(nullptr);
+
+    test(vPrimOp, "<PRIMOP>");
+}
+
+TEST_F(ValuePrintingTests, vPrimOpApp)
+{
+    Value vPrimOpApp;
+    vPrimOpApp.mkPrimOpApp(nullptr, nullptr);
+
+    test(vPrimOpApp, "<PRIMOP-APP>");
+}
+
+TEST_F(ValuePrintingTests, vExternal)
+{
+    struct MyExternal : ExternalValueBase
+    {
+    public:
+        std::string showType() const override
+        {
+            return "";
+        }
+        std::string typeOf() const override
+        {
+            return "";
+        }
+        virtual std::ostream & print(std::ostream & str) const override
+        {
+            str << "testing-external!";
+            return str;
+        }
+    } myExternal;
+    Value vExternal;
+    vExternal.mkExternal(&myExternal);
+
+    test(vExternal, "testing-external!");
+}
+
+TEST_F(ValuePrintingTests, vFloat)
+{
+    Value vFloat;
+    vFloat.mkFloat(2.0);
+
+    test(vFloat, "2");
+}
+
+TEST_F(ValuePrintingTests, vBlackhole)
+{
+    Value vBlackhole;
+    vBlackhole.mkBlackhole();
+    test(vBlackhole, "«potential infinite recursion»");
+}
+
+} // namespace nix