fix: Internal error on warning injection (#3177)

tests/unit/web/LoadWarningTests.cpp

@@ -0,0 +1,87 @@
+#include "rpc/Errors.hpp"
+#include "web/LoadWarning.hpp"
+
+#include <gtest/gtest.h>
+
+#include <cstdint>
+#include <string>
+
+using namespace web;
+
+namespace {
+
+struct LoadWarningNonJsonTest : testing::TestWithParam<std::string> {};
+
+}  // namespace
+
+INSTANTIATE_TEST_SUITE_P(
+    NonJsonBodies,
+    LoadWarningNonJsonTest,
+    testing::Values(
+        "Unable to parse JSON from the request",
+        "Null method",
+        "method is empty",
+        "method is not string",
+        "params unparsable",
+        "Bad target",
+        "Too many requests for one connection",
+        "",
+        "[1, 2, 3]",  // valid JSON, but not an object
+        "42",
+        "null",
+        R"("a string")"
+    )
+);
+
+TEST_P(LoadWarningNonJsonTest, ReturnsNulloptInsteadOfThrowing)
+{
+    EXPECT_NO_THROW({ EXPECT_FALSE(withLoadWarning(GetParam()).has_value()); });
+}
+
+TEST(LoadWarningTest, AddsWarningToJsonObjectWithoutExistingWarnings)
+{
+    auto const result = withLoadWarning(R"({"result": {"status": "success"}})");
+
+    ASSERT_TRUE(result.has_value());
+    // NOLINTBEGIN(bugprone-unchecked-optional-access)
+    EXPECT_EQ(result->at("warning").as_string(), "load");
+    ASSERT_EQ(result->at("warnings").as_array().size(), 1);
+    EXPECT_EQ(
+        result->at("warnings").as_array().at(0).as_object().at("id").as_int64(),
+        static_cast<int64_t>(rpc::WarningCode::WarnRpcRateLimit)
+    );
+    EXPECT_EQ(result->at("result").as_object().at("status").as_string(), "success");
+    // NOLINTEND(bugprone-unchecked-optional-access)
+}
+
+TEST(LoadWarningTest, AppendsToExistingWarningsArray)
+{
+    auto const result =
+        withLoadWarning(R"({"warnings": [{"id": 2001, "message": "already here"}]})");
+
+    ASSERT_TRUE(result.has_value());
+    // NOLINTBEGIN(bugprone-unchecked-optional-access)
+    EXPECT_EQ(result->at("warning").as_string(), "load");
+    ASSERT_EQ(result->at("warnings").as_array().size(), 2);
+    EXPECT_EQ(result->at("warnings").as_array().at(0).as_object().at("id").as_int64(), 2001);
+    EXPECT_EQ(
+        result->at("warnings").as_array().at(1).as_object().at("id").as_int64(),
+        static_cast<int64_t>(rpc::WarningCode::WarnRpcRateLimit)
+    );
+    // NOLINTEND(bugprone-unchecked-optional-access)
+}
+
+TEST(LoadWarningTest, ReplacesNonArrayWarningsField)
+{
+    auto const result = withLoadWarning(R"({"warnings": "not an array"})");
+
+    ASSERT_TRUE(result.has_value());
+    // NOLINTBEGIN(bugprone-unchecked-optional-access)
+    ASSERT_TRUE(result->at("warnings").is_array());
+    ASSERT_EQ(result->at("warnings").as_array().size(), 1);
+    EXPECT_EQ(
+        result->at("warnings").as_array().at(0).as_object().at("id").as_int64(),
+        static_cast<int64_t>(rpc::WarningCode::WarnRpcRateLimit)
+    );
+    // NOLINTEND(bugprone-unchecked-optional-access)
+}