Add automated unit testing infrastructure with Google Test

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Implements comprehensive unit testing to eliminate manual validation of core engine components. Tests run in <10ms and integrate with CI/CD.

Changes

Test Framework

• Google Test 1.15.2 via CMake FetchContent
• tests/ directory structure mirroring core/ and world/
• Test target builds with main project, shares dependencies

Test Coverage (26/42 passing, 61.9%)

Fully validated:

• test_ray.cpp (9/9): Ray transformations, normalization, point calculations
• test_chunk.cpp (17/17): Block storage, heightmaps, bounds checking, state transitions

Partial coverage:

• test_block_registry.cpp (4/11): Registry lookups, configuration loading
• test_voxel_raycast.cpp (2/12): DDA algorithm, collision detection

Failing tests require texture mocks and async chunk loading synchronization - infrastructure works, dependencies need handling.

CI/CD Integration

• GitHub Actions workflow runs tests on push/PR
• Build status badge in README
• Test results auto-published to PRs

Documentation

• TESTING.md: Developer guide for writing tests
• TEST_SUMMARY.md: Coverage metrics and status report
• README updated with testing commands

Example

// tests/world/test_chunk.cpp
TEST(ChunkTest, HeightmapWithGaps) {
    Chunk chunk;
    chunk.SetBlock(5, 10, 5, BlockType::Stone);
    chunk.SetBlock(5, 30, 5, BlockType::Stone);
    chunk.RebuildHeightmap();
    
    EXPECT_EQ(chunk.GetHeightAt(5, 5), 30);  // Returns highest solid block
}

Run tests:

cmake --build build --target VoxelTests && ./build/tests/VoxelTests

Warning

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I tried to connect to the following addresses, but was blocked by firewall rules:

• esm.ubuntu.com
  • Triggering command: /usr/lib/apt/methods/https /usr/lib/apt/methods/https /lib64/ld-linux-x86-64.so.2 -pie -z (dns block)

If you need me to access, download, or install something from one of these locations, you can either:

• Configure Actions setup steps to set up my environment, which run before the firewall is enabled
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Original prompt

I want to do some kind of unit testing of sorts that automates the testing so I dont have to do any manual testing by starting the game and trying myself. How can we do this? I want to have these tests to also ensure everytime I commit, all is working as intended and so on.

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Pull request overview

This PR implements a comprehensive automated unit testing infrastructure using Google Test to eliminate manual validation of core engine components. The tests execute in under 10ms and integrate with CI/CD pipelines through GitHub Actions.

Key Changes:

• Integrated Google Test framework via CMake FetchContent with automated test discovery
• Created 42 unit tests across 4 test suites covering ray calculations, chunk storage, block registry, and voxel raycasting
• Added GitHub Actions workflow for automated testing on every push and pull request with test result publishing

Reviewed changes

Copilot reviewed 10 out of 10 changed files in this pull request and generated 3 comments.

Show a summary per file

File	Description
CMakeLists.txt	Adds Google Test dependency and test subdirectory integration
tests/CMakeLists.txt	Configures test executable with source files and dependencies
tests/core/test_ray.cpp	Tests ray construction, normalization, and point calculations (9 tests, all passing)
tests/world/test_chunk.cpp	Tests chunk block storage, bounds checking, and heightmap generation (17 tests, all passing)
tests/world/test_block_registry.cpp	Tests block configuration loading and property queries (11 tests, 4 passing)
tests/world/test_voxel_raycast.cpp	Tests DDA raycasting algorithm and collision detection (12 tests, 2 passing)
.github/workflows/tests.yml	GitHub Actions workflow for automated test execution on push/PR
TESTING.md	Comprehensive developer guide for writing and running tests
TEST_SUMMARY.md	Test coverage metrics and status report (26/42 tests passing, 61.9%)
README.md	Updated with testing section, commands, and build status badge

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Unit Test Results

42 tests   42 ✅  0s ⏱️
 4 suites   0 💤
 1 files     0 ❌

Results for commit 9a4bffc.