Automated Test Suite

Purpose

The Automated Test Suite addresses the need for rigorous validation of JSON parsing, structural integrity, and serialization within the broader scope of the JSON Serialization and Testing topic. While the parent topic outlines capabilities to serialize JSON and ensure parser correctness, this subtopic focuses specifically on the systematic verification of those capabilities through automated tests. It ensures that the JSON processing library correctly interprets diverse JSON input formats, maintains structural equality, and produces consistent, pretty-printed output. Additionally, the suite enhances developer experience by providing clear, colored terminal feedback indicating pass/fail status and detailed mismatch context when tests fail.

Functionality

The Automated Test Suite operates by executing defined test cases that:

1. Load JSON Inputs: Reads JSON text files containing a variety of test cases, from simple arrays to complex nested objects with multiple data types.

2. Parse JSON Data: Uses the core parsing function (json_parse()) to convert input JSON strings into the internal json_value tree representation, as defined in JSON Parsing and Representation.

3. Serialize Parsed Data: Converts the in-memory JSON structure back into formatted JSON text using the serialization function (json_stringify()), aligning with the pretty-printing utilities under Pretty-Printing JSON.

4. Compare Structures: Validates that the original JSON input and the serialized output represent the same JSON structure, regardless of formatting or key order. This structural equality check uses the deep comparison function (json_equal()), part of the JSON Manipulation and Comparison topic.

5. Report Results: Provides colored terminal feedback using ANSI escape codes to indicate success (green) or failure (red). On failure, it outputs the precise location and textual context of the mismatch to aid debugging.

6. Test Macros and Assertions: Employs a lightweight testing framework with macros to manage test setup, execution, assertions, and teardown. This framework automatically tracks the number of tests run and passed.

Key Workflow Steps

• Initialization: The suite enables ANSI color support on Windows consoles and sets up global variables for colored output.

• Test Execution: Each test function reads a JSON file, parses it, serializes the parsed structure back to text, then asserts structural equality.

• Error Diagnostics: If structural equality fails, the suite locates the first differing byte in the inputs and prints surrounding context with offsets.

• Test Harness: The main() function in src/main.c initializes the environment, runs all test cases, and finalizes with a summary.

Code Snippet: Structural Equality Check and Diagnostic

bool test_json_equal(const char *a, const char *b) {
  // Parse both JSON strings
  const json_value *va = json_parse(a);
  const json_value *vb = json_parse(b);
  if (!va || !vb) return false;

  // Compare JSON structures deeply
  bool eq = json_equal(va, vb);

  if (!eq) {
    // Locate first differing byte ignoring whitespace
    // Print mismatch context around that position
  }

  json_free(va);
  json_free(vb);
  return eq;
}

This function underpins the validation by combining parsing, deep comparison, and detailed error reporting.

Test Macros Example

The macros defined in test/test.h simplify writing test cases:

TEST(test_simple_json_parsing) {
  // Setup and run test logic
  ASSERT(test_json_equal(original_json, serialized_json));
  END_TEST;
}

They manage counting tests, reporting status, and handling assertions with minimal boilerplate.

Integration

The Automated Test Suite is tightly integrated with the core JSON processing components and other subtopics:

• With JSON Parsing and Representation (80084): Invokes json_parse() to build the internal JSON tree from input text.

• With Pretty-Printing JSON subtopic: Uses json_stringify() to serialize the JSON tree back to formatted text, testing the serialization fidelity.

• With JSON Manipulation and Comparison (80082): Employs json_equal() for deep equality checks to confirm structural consistency between original and serialized JSON.

• With the Parent Topic (80083): Implements the testing portion that verifies the serialization and overall parser correctness, fulfilling the parent topic's promise of a comprehensive test suite.

• Build and Execution: The src/main.c file serves as the test runner, invoking all test cases and managing initialization and finalization phases.

This integration ensures that the Automated Test Suite exercises the full JSON processing pipeline and verifies cross-functional correctness.

flowchart LR
Start["Test Runner main()"] --> Init[Initialize Test Environment]
Init --> Load1[Load JSON File]
Load1 --> Parse1[Parse JSON Input]
Parse1 --> Serialize1[Serialize Parsed JSON]
Serialize1 --> Compare[Compare Original & Serialized]
Compare -->|Equal| Pass[Test Passed]
Compare -->|Not Equal| Fail[Test Failed]
Fail --> Report[Print Mismatch Context]
Pass --> NextTest{More Tests?}
Fail --> NextTest
NextTest -->|Yes| Load1
NextTest -->|No| End[Finalize & Report Summary]

This flowchart illustrates the core process of each test cycle, from loading input to reporting results, highlighting how structural equality verification is central to the suite.