ArduinoJson/extras/tests/JsonDeserializer/nestingLimit.cpp

// ArduinoJson - https://arduinojson.org
// Copyright © 2014-2025, Benoit BLANCHON
// MIT License

#include <ArduinoJson.h>
#include <catch.hpp>

#include <sstream>

#include "Literals.hpp"

#define SHOULD_WORK(expression) REQUIRE(DeserializationError::Ok == expression);
#define SHOULD_FAIL(expression) \
  REQUIRE(DeserializationError::TooDeep == expression);

TEST_CASE("JsonDeserializer nesting") {
  JsonDocument doc;

  SECTION("Input = const char*") {
    SECTION("limit = 0") {
      DeserializationOption::NestingLimit nesting(0);
      SHOULD_WORK(deserializeJson(doc, "\"toto\"", nesting));
      SHOULD_WORK(deserializeJson(doc, "123", nesting));
      SHOULD_WORK(deserializeJson(doc, "true", nesting));
      SHOULD_FAIL(deserializeJson(doc, "[]", nesting));
      SHOULD_FAIL(deserializeJson(doc, "{}", nesting));
      SHOULD_FAIL(deserializeJson(doc, "[\"toto\"]", nesting));
      SHOULD_FAIL(deserializeJson(doc, "{\"toto\":1}", nesting));
    }

    SECTION("limit = 1") {
      DeserializationOption::NestingLimit nesting(1);
      SHOULD_WORK(deserializeJson(doc, "[\"toto\"]", nesting));
      SHOULD_WORK(deserializeJson(doc, "{\"toto\":1}", nesting));
      SHOULD_FAIL(deserializeJson(doc, "{\"toto\":{}}", nesting));
      SHOULD_FAIL(deserializeJson(doc, "{\"toto\":[]}", nesting));
      SHOULD_FAIL(deserializeJson(doc, "[[\"toto\"]]", nesting));
      SHOULD_FAIL(deserializeJson(doc, "[{\"toto\":1}]", nesting));
    }
  }

  SECTION("char* and size_t") {
    SECTION("limit = 0") {
      DeserializationOption::NestingLimit nesting(0);
      SHOULD_WORK(deserializeJson(doc, "\"toto\"", 6, nesting));
      SHOULD_WORK(deserializeJson(doc, "123", 3, nesting));
      SHOULD_WORK(deserializeJson(doc, "true", 4, nesting));
      SHOULD_FAIL(deserializeJson(doc, "[]", 2, nesting));
      SHOULD_FAIL(deserializeJson(doc, "{}", 2, nesting));
      SHOULD_FAIL(deserializeJson(doc, "[\"toto\"]", 8, nesting));
      SHOULD_FAIL(deserializeJson(doc, "{\"toto\":1}", 10, nesting));
    }

    SECTION("limit = 1") {
      DeserializationOption::NestingLimit nesting(1);
      SHOULD_WORK(deserializeJson(doc, "[\"toto\"]", 8, nesting));
      SHOULD_WORK(deserializeJson(doc, "{\"toto\":1}", 10, nesting));
      SHOULD_FAIL(deserializeJson(doc, "{\"toto\":{}}", 11, nesting));
      SHOULD_FAIL(deserializeJson(doc, "{\"toto\":[]}", 11, nesting));
      SHOULD_FAIL(deserializeJson(doc, "[[\"toto\"]]", 10, nesting));
      SHOULD_FAIL(deserializeJson(doc, "[{\"toto\":1}]", 12, nesting));
    }
  }

  SECTION("Input = std::string") {
    SECTION("limit = 0") {
      DeserializationOption::NestingLimit nesting(0);
      SHOULD_WORK(deserializeJson(doc, "\"toto\""_s, nesting));
      SHOULD_WORK(deserializeJson(doc, "123"_s, nesting));
      SHOULD_WORK(deserializeJson(doc, "true"_s, nesting));
      SHOULD_FAIL(deserializeJson(doc, "[]"_s, nesting));
      SHOULD_FAIL(deserializeJson(doc, "{}"_s, nesting));
      SHOULD_FAIL(deserializeJson(doc, "[\"toto\"]"_s, nesting));
      SHOULD_FAIL(deserializeJson(doc, "{\"toto\":1}"_s, nesting));
    }

    SECTION("limit = 1") {
      DeserializationOption::NestingLimit nesting(1);
      SHOULD_WORK(deserializeJson(doc, "[\"toto\"]"_s, nesting));
      SHOULD_WORK(deserializeJson(doc, "{\"toto\":1}"_s, nesting));
      SHOULD_FAIL(deserializeJson(doc, "{\"toto\":{}}"_s, nesting));
      SHOULD_FAIL(deserializeJson(doc, "{\"toto\":[]}"_s, nesting));
      SHOULD_FAIL(deserializeJson(doc, "[[\"toto\"]]"_s, nesting));
      SHOULD_FAIL(deserializeJson(doc, "[{\"toto\":1}]"_s, nesting));
    }
  }

  SECTION("Input = std::istream") {
    SECTION("limit = 0") {
      DeserializationOption::NestingLimit nesting(0);
      std::istringstream good("true");
      std::istringstream bad("[]");
      SHOULD_WORK(deserializeJson(doc, good, nesting));
      SHOULD_FAIL(deserializeJson(doc, bad, nesting));
    }

    SECTION("limit = 1") {
      DeserializationOption::NestingLimit nesting(1);
      std::istringstream good("[\"toto\"]");
      std::istringstream bad("{\"toto\":{}}");
      SHOULD_WORK(deserializeJson(doc, good, nesting));
      SHOULD_FAIL(deserializeJson(doc, bad, nesting));
    }
  }
}